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65-549: NHS Blood and Transplant is an executive special health authority of the United Kingdom's Department of Health and Social Care . It was established on 1 October 2005 to take over the responsibilities of two separate NHS agencies: UK Transplant (now renamed Organ Donation and Transplantation), founded by Dr. Geoffrey Tovey in 1972, and the National Blood Service (now renamed Blood Donation). Its remit

130-424: A few days, regular and frequent donors are in great demand and that is why platelet donors are asked to attend at least 8–10 times per year. Organ Donation and Transplantation ensures that organs donated for transplant are matched and allocated to patients in a fair and unbiased way. Matching, particularly in the case of kidneys, is so important that donation and allocation needs to be organised nationally. The larger

195-449: A first approximation, the shape can be considered similar to oblate spheroids , with a semiaxis ratio of 2 to 8. This approximation can be used to model the hydrodynamic and optical properties of a population, as well as to restore the geometric parameters of individual measured platelets by flow cytometry . More accurate biophysical models of platelet surface morphology that model its shape from first principles, make it possible to obtain

260-476: A more realistic platelet geometry in a calm and activated state. The fundamental function of platelets is to clump together to stop acute bleeding. This process is complex, as more than 193 proteins and 301 interactions are involved in platelet dynamics. Despite much overlap, platelet function can be modeled in three steps: Thrombus formation on an intact endothelium is prevented by nitric oxide , prostacyclin , and CD39 . Endothelial cells attach to

325-701: A multitude of microthrombi of similar composition to that in physiological immunothrombosis — fibrin, platelets, neutrophils and NETs. Platelets rapidly deploy to sites of injury or infection, and potentially modulate inflammatory processes by interacting with leukocytes and secreting cytokines , chemokines , and other inflammatory mediators. Platelets also secrete platelet-derived growth factor (PDGF). Platelets modulate neutrophils by forming platelet-leukocyte aggregates (PLAs). These formations induce upregulated production of αmβ2 ( Mac-1 ) integrin in neutrophils. Interaction with PLAs also induces degranulation and increased phagocytosis in neutrophils. Platelets are

390-463: A pathologic and excessive quantity of clot. In a third context it is used to contrast the result from the process: thrombus is the result, thrombosis is the process. Structurally the platelet can be divided into four zones, from peripheral to innermost: Circulating inactivated platelets are biconvex discoid (lens-shaped) structures, 2–3 μm in greatest diameter. Activated platelets have cell membrane projections covering their surface. In

455-676: A receptor for IgG's constant fragment (Fc). When activated and bound to IgG opsonised bacteria, platelets release reactive oxygen species (ROS), antimicrobial peptides, defensins , kinocidins and proteases , killing the bacteria directly. Platelets also secrete proinflammatory and procoagulant mediators such as inorganic polyphosphates or platelet factor 4 (PF4), connecting innate and adaptive immune responses. Spontaneous and excessive bleeding can occur because of platelet disorders. This bleeding can be caused by deficient numbers of platelets, dysfunctional platelets, or platelet densities over 1 million/microliter. (The excessive numbers create

520-480: A record high in organ donation and transplantation together with an increase in the number of people signing up to donate blood. The Core System Modernisation Programme which was meant to modernise the organisation’s information technogy systems was abandoned in 2018 with costs of £26 million written off. The National Blood Service, now renamed NHS Blood Donation , is the organisation for England which collects blood and other tissues, tests, processes, and supplies all

585-777: A relative von Willebrand factor deficiency due to sequestration.) Bleeding due to a platelet disorder or a coagulation factor disorder can be distinguished by the characteristics and location of the bleeding. Platelet bleeding involves bleeding from a cut is prompt and excessive, but can be controlled by pressure; spontaneous bleeding into the skin which causes a purplish stain named by its size: petechiae , purpura , ecchymoses ; bleeding into mucous membranes causing bleeding gums, nose bleed, and gastrointestinal bleeding; menorrhagia; and intraretinal and intracranial bleeding. Excessive numbers of platelets, and/or normal platelets responding to abnormal vessel walls, can result in venous thrombosis and arterial thrombosis . The symptoms depend on

650-494: A result of turning on the GPIIb/IIIa receptor, allowing these receptors to bind with vWF or fibrinogen . Each platelet has around 60,000 of these receptors. When any one or more of at least nine different platelet surface receptors are turned on during activation, intraplatelet signaling pathways cause existing GpIIb/IIIa receptors to change shape — curled to straight — and thus become capable of binding. Since fibrinogen

715-458: A significant majority stake to Bain Capital. The business benefited from investment and growth, enabling full privatisation, achieved when a group controlled by Creat Group Corporation acquired it in 2016. The NHS Organ Donor Register is a national, confidential list of people who are willing to become donors after their death. It can be quickly accessed to see whether an individual has registered

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780-563: A willingness to be an organ donor. NHSBT operates the largest blood processing facility in Europe, capable of processing 1 million units a year. The site also houses the International Blood Group Reference Laboratory, one of the world’s leading laboratories in rare blood identification. Special health authority They are a type of "Non-Administratively Classified Government Entities" of

845-415: A year (once every 16 weeks). Since February 2012, male donors have been allowed to donate up to four times a year. In 2013–14 1,986 people complained they had been turned away from walk-in sessions. 1,949 said they did not have their blood taken even when they had made an appointment. Besides the main blood donations, known as "whole blood", platelets are also collected. As platelets can only be stored for

910-449: Is a rod-like protein with nodules on either end capable of binding GPIIb/IIIa, activated platelets with exposed GPIIb/IIIa can bind fibrinogen to aggregate. GPIIb/IIIa may also further anchor the platelets to subendothelial vWF for additional structural stabilisation. Classically it was thought that this was the only mechanism involved in aggregation, but three other mechanisms have been identified which can initiate aggregation, depending on

975-585: Is a system for analysing platelet function in which citrated whole blood is aspirated through a disposable cartridge containing an aperture within a membrane coated with either collagen and epinephrine or collagen and ADP. These agonists induce platelet adhesion, activation and aggregation, leading to rapid occlusion of the aperture and cessation of blood flow termed the closure time (CT). An elevated CT with EPI and collagen can indicate intrinsic defects such as von Willebrand disease , uremia , or circulating platelet inhibitors. A follow-up test involving collagen and ADP

1040-444: Is initiated either by immune cells by activating their pattern recognition receptors (PRRs), or by platelet-bacterial binding. Platelets can bind to bacteria either directly through thrombocytic PRRs and bacterial surface proteins, or via plasma proteins that bind both to platelets and bacteria. Monocytes respond to bacterial pathogen-associated molecular patterns (PAMPs), or damage-associated molecular patterns (DAMPs) by activating

1105-436: Is mixed with saline and a platelet agonist in a single-use cuvette with two pairs of electrodes. The increase in impedance between the electrodes as platelets aggregate onto them, is measured and visualized as a curve. In light transmission aggregometry (LTA), platelet-rich plasma is placed between a light source and a photocell . Unaggregated plasma allows relatively little light to pass through. After adding an agonist,

1170-442: Is the chemical motor that pulls the invaginated OCS out of the interior of the platelet, like turning pants pockets inside out, creating the dendrites. This process is similar to the mechanism of contraction in a muscle cell . The entire OCS thus becomes indistinguishable from the initial platelet membrane as it forms the "fried egg". This dramatic increase in surface area comes about with neither stretching nor adding phospholipids to

1235-448: Is to provide a reliable, efficient supply of blood, organs and associated services to the NHS. Since NHSBT was established, the organisation has maintained or improved the quality of the services delivered to patients, stabilised the rising cost of blood, and centralised a number of corporate services. It has the responsibility for optimising the supply of blood, organs and tissues and raising

1300-450: Is used to indicate if the abnormal CT with collagen and EPI was caused by the effects of acetyl sulfosalicylic acid (aspirin) or medications containing inhibitors. The PFA-100 is highly sensitive to von Willebrand disease, but is only moderately sensitive to defects in platelet function. Low platelet concentration is called thrombocytopenia , and is due to either decreased production or increased destruction. Elevated platelet concentration

1365-540: The Department of Health of the United Kingdom . Special health authorities are independent, but can be subject to ministerial direction like other NHS bodies. While special health authorities may provide services direct to the public, most are concerned with improving the ability of other parts of the NHS to deliver effective health care. Special health authorities were set to provide a national service to

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1430-560: The National Health Service Act 2006 . Platelets Platelets or thrombocytes (from Ancient Greek θρόμβος ( thrómbos )  'clot' and κύτος ( kútos )  'cell') are a blood component whose function (along with the coagulation factors ) is to react to bleeding from blood vessel injury by clumping, thereby initiating a blood clot . Platelets have no cell nucleus ; they are fragments of cytoplasm derived from

1495-520: The PI3K/Akt pathway during a first wave of aggregation, leading to thrombin generation and PAR‐1 activation, which evokes a second wave of aggregation. Platelet activation begins seconds after adhesion occurs. It is triggered when collagen from the subendothelium binds with its receptors ( GPVI receptor and integrin α2β1) on the platelet. GPVI is associated with the Fc receptor gamma chain and leads via

1560-515: The coagulation cascade , with resultant fibrin deposition and linking (secondary hemostasis). These processes may overlap: the spectrum is from a predominantly platelet plug, or "white clot" to a predominantly fibrin, or "red clot" or the more typical mixture. Berridge adds retraction and platelet inhibition as fourth and fifth steps, while others would add a sixth step, wound repair . Platelets participate in both innate and adaptive intravascular immune responses. In addition to facilitating

1625-419: The megakaryocytes of the bone marrow or lung, which then enter the circulation. Platelets are found only in mammals, whereas in other vertebrates (e.g. birds , amphibians ), thrombocytes circulate as intact mononuclear cells . One major function of platelets is to contribute to hemostasis : the process of stopping bleeding at the site of interrupted endothelium . They gather at the site and, unless

1690-485: The 12 English Regional Transfusion Centres in 1994. The National Blood Service became a nationally coordinated body in 1996. The service operates out of fifteen centres, and collects around 2.1 million donations per year and supplies 8,000 units of blood every day. Service directors proposed a reconfiguration and centralisation strategy in 2006, based on the closure of most local processing and testing labs, and subsequent operation out of just three large 'supercentres' to serve

1755-767: The NETosis and phagocytosis. Platelets also participate in chronic inflammatory disease, such as synovitis or rheumatoid arthritis . Platelets are activated by collagen receptor glycoprotein IV (GPVI). Proinflammatory platelet microvesicles trigger constant cytokine secretion from neighboring fibroblast-like synoviocytes , most prominently Il-6 and Il-8 . Inflammatory damage to the surrounding extracellular matrix continuously reveals more collagen, maintaining microvesicle production. Activated platelets are able to participate in adaptive immunity , interacting with antibodies . They are able to specifically bind IgG through FcγRIIA ,

1820-812: The NHS or the public, under section 11 of the National Health Service Act 1977 . Prior to the repeal of the whole of the 1977 Act by the NHS (Consequential Provisions) Act 2006, special health authorities included both infrastructure support organisations and national/specialist treatment providers such as the Special Hospitals Service Authority and the Bethlem Royal and Maudsley Special Health Authority . These direct clinical service providers were progressively merged with local NHS trusts and consequently with mainstream governance and funding arrangements. The support special health authorities are now provided for under section 28 of

1885-823: The South West from 1946 and since the formation of the NHS the service was primarily a mobile collection service visiting all parts of the mainly rural community. Originally Local Organisers called up the Donors from their own lists; this only changed in the 1990s. This link with the Local Organisers was inherited from the Wartime Red Cross (mainly) and St. Johns blood collection teams. These mobile teams continue to collect, but two centres – Bristol and Plymouth (Derriford) – have static bases in local venues. Currently, blood donation sessions are set up throughout

1950-436: The activation of a tyrosine kinase cascade finally to the activation of PLC-gamma2 ( PLCG2 ) and more calcium release. Tissue factor also binds to factor VII in the blood, which initiates the extrinsic coagulation cascade to increase thrombin production. Thrombin is a potent platelet activator, acting through Gq and G12. These are G protein-coupled receptors and they turn on calcium-mediated signaling pathways within

2015-426: The bacteria. Although thrombosis, blood coagulation in intact blood vessels, is usually viewed as a pathological immune response, leading to obturation of lumen of blood vessel and subsequent hypoxic tissue damage, in some cases, directed thrombosis, called immunothrombosis, can locally control the spread of an infection. The thrombosis is directed in concordance of platelets, neutrophils and monocytes . The process

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2080-445: The binding of these coagulation factors. In addition to interacting with vWF and fibrin, platelets interact with thrombin, Factors X, Va, VIIa, XI, IX, and prothrombin to complete formation via the coagulation cascade. Human platelets do not express tissue factor . Rat platelets do express tissue factor protein and carry both tissue factor pre-mRNA and mature mRNA. Platelet aggregation begins minutes after activation, and occurs as

2145-470: The blood of non-mammalian vertebrates: they are the functional equivalent of platelets, but circulate as intact cells rather than cytoplasmic fragments of bone marrow megakaryocytes. In some contexts, the word thrombus is used interchangeably with the word clot , regardless of its composition (white, red, or mixed). In other contexts it is used to contrast a normal from an abnormal clot: thrombus arises from physiologic hemostasis, thrombosis arises from

2210-484: The clotting process, platelets contain cytokines and growth factors which can promote wound healing and regeneration of damaged tissues. The term thrombocyte (clot cell) came into use in the early 1900s and is sometimes used as a synonym for platelet; but not generally in the scientific literature, except as a root word for other terms related to platelets (e.g. thrombocytopenia meaning low platelets). The term thrombocytes are proper for mononuclear cells found in

2275-429: The connection between thrombocytes and immune cells. The platelet cell membrane has receptors for collagen. Following rupture of the blood vessel wall, platelets are exposed and adhere to the collagen in the surrounding tissue. As hemostasis is a basic function of thrombocytes in mammals, it also has its uses in possible infection confinement. In case of injury, platelets, together with the coagulation cascade, provide

2340-435: The country and take place in many diverse venues, from village halls, workplaces and mobile collection units (known as Bloodmobiles ). Donors are generally required to be fit and healthy, weigh 50 kilograms (110 lb; 7 st 12 lb) and aged between 17 and 60. However, regular (healthy) donors are permitted to donate past the age of 60 as long as they remain healthy. Donors are encouraged to give blood up to three times

2405-489: The coupled Gs protein to increase adenylate cyclase activity and increases the production of cAMP, further promoting the efflux of calcium and reducing intracellular calcium availability for platelet activation. ADP on the other hand binds to purinergic receptors on the platelet surface. Since the thrombocytic purinergic receptor P2Y12 is coupled to Gi proteins, ADP reduces platelet adenylate cyclase activity and cAMP production, leading to accumulation of calcium inside

2470-483: The exterior. Bound and activated platelets degranulate to release platelet chemotactic agents to attract more platelets to the site of endothelial injury. Granule characteristics: As shown by flow cytometry and electron microscopy , the most sensitive sign of activation, when exposed to platelets using ADP, are morphological changes. Mitochondrial hyperpolarization is a key event in initiating morphology changes. Intraplatelet calcium concentration increases, stimulating

2535-455: The extrinsic pathway of coagulation. Neutrophils facilitate the blood coagulation by NETosis , while platelets facilitate neutrophils' NETosis. NETs bind tissue factor, binding the coagulation centers to the location of infection. They also activate the intrinsic coagulation pathway by providing its negatively charged surface to the factor XII. Other neutrophil secretions, such as proteolytic enzymes which cleave coagulation inhibitors, also bolster

2600-552: The first line of defense by forming a blood clot. Hemostasis and host defense were thus intertwined in evolution. For example, in the Atlantic horseshoe crab (estimated to be over 400 million years old), the only blood cell type, the amebocyte , facilitates both the hemostatic function and the encapsulation and phagocytosis of pathogens by means of exocytosis of intracellular granules containing bactericidal defense molecules. Blood clotting supports immune function by trapping

2665-753: The hospitals in England. Other official blood services in the United Kingdom include the Northern Ireland Blood Transfusion Service , Scottish National Blood Transfusion Service and the Welsh Blood Service . The National Blood Service was formed in 1946 as the National Blood Transfusion Service of England and Wales (NBTS). The National Blood Authority was established as a Special Health Authority in 1993 and assumed control of

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2730-433: The interplay between the microtubule/actin filament complex. The continuous changes in shape from the unactivated to the fully activated platelet are best seen via scanning electron microscopy . The three steps along this path are named early dendritic , early spread, and spread . The surface of the unactivated platelet looks similar to the surface of the brain–a wrinkled appearance from numerous shallow folds that increase

2795-408: The interruption is physically too large, they plug the hole. First, platelets attach to substances outside the interrupted endothelium: adhesion . Second, they change shape, turn on receptors and secrete chemical messengers : activation . Third, they connect to each other through receptor bridges: aggregation . Formation of this platelet plug (primary hemostasis) is associated with activation of

2860-455: The largest source of soluble CD40L which induces production of reactive oxygen species (ROS) and upregulate expression of adhesion molecules, such as E-selectin , ICAM-1 , and VCAM-1 , in neutrophils, activates macrophages and activates cytotoxic response in T and B lymphocytes . Mammalian platelets lacking nucleus are able to conduct autonomous locomotion. Platelets are active scavengers, scaling walls of blood vessels and reorganising

2925-661: The northern suburbs of Bristol, in 1993. In July 2000, UK Transplant was formed with a new, extended remit to increase organ donation rates. In October 2005 UK Transplant merged with the National Blood Service and the Bio Products Laboratory to form NHS Blood and Transplant. In 2010, the Bio Products Laboratory became a limited company owned directly by the Department of Health. The Department of Health partly privatised it in 2013, selling

2990-433: The other to form the final fibrin-crosslinked thrombus. Collagen-mediated GPVI signalling increases the platelet production of thromboxane A2 (TXA2) and decreases the production of prostacyclin . This occurs by altering the metabolic flux of platelet's eicosanoid synthesis pathway, which involves enzymes phospholipase A2 , cyclo-oxygenase 1 , and thromboxane-A synthase . Platelets secrete thromboxane A2, which acts on

3055-413: The platelet activator ADP . Resting platelets maintain active calcium efflux via a cyclic AMP -activated calcium pump. Intracellular calcium concentration determines platelet activation status, as it is the second messenger that drives platelet conformational change and degranulation. Endothelial prostacyclin binds to prostanoid receptors on the surface of resting platelets. This event stimulates

3120-504: The platelet by inactivating the cAMP calcium efflux pump. The other ADP-receptor P2Y1 couples to Gq that activates phospholipase C-beta 2 ( PLCB2 ), resulting in inositol 1,4,5-trisphosphate (IP3) generation and intracellular release of more calcium. This together induces platelet activation. Endothelial ADPase degrades ADP and prevents this from happening. Clopidogrel and related antiplatelet medications also work as purinergic receptor P2Y12 antagonists . Data suggest that ADP activates

3185-441: The platelet membrane. Platelet activation causes its membrane surface to become negatively charged. One of the signaling pathways turns on scramblase , which moves negatively charged phospholipids from the inner to the outer platelet membrane surface. These phospholipids then bind the tenase and prothrombinase complexes, two of the sites of interplay between platelets and the coagulation cascade. Calcium ions are essential for

3250-447: The platelet's own thromboxane receptors on the platelet surface (hence the so-called "out-in" mechanism), and those of other platelets. These receptors trigger intraplatelet signaling, which converts GPIIb/IIIa receptors to their active form to initiate aggregation . Platelets contain dense granules , lambda granules, and alpha granules . Activated platelets secrete the contents of these granules through their canalicular systems to

3315-406: The platelet, overcoming the baseline calcium efflux. Families of three G proteins (Gq, Gi, G12) operate together for full activation. Thrombin also promotes secondary fibrin-reinforcement of the platelet plug. Platelet activation in turn degranulates and releases factor V and fibrinogen , potentiating the coagulation cascade. Platelet plugging and coagulation occur simultaneously, with each inducing

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3380-409: The platelets aggregate, increasing light transmission, which is detected by a photocell. Whole blood impedance aggregometry (WBA) measures the change in electrical impedance between two electrodes when platelet aggregation is induced by an agonist. Whole blood lumiaggregometry may increase the test sensitivity to impairment of platelet granule secretion. The PFA-100 (Platelet Function Assay — 100)

3445-493: The pool of organs, the better the likelihood there is of a good match. Unlike some other NHS organisations, it does not have a direct relationship with patients and do not provide "hands on" care. However, in providing support to transplantation services across England, everything it does affects the quality of service delivered to individual patients. In 1968, the National Tissue Typing and Reference Laboratory

3510-501: The population average between 250,000 and 260,000 cells per mm (equivalent to per microliter), but the typical laboratory accepted normal range is between 150,000 and 400,000 cells per mm or 150–400 × 10 per liter. On a stained blood smear , platelets appear as dark purple spots, about 20% of the diameter of red blood cells. The smear reveals size, shape, qualitative number, and clumping . A healthy adult typically has 10 to 20 times more red blood cells than platelets. Bleeding time

3575-452: The process. In case of imbalance throughout the regulation of immunothrombosis, this process can become aberrant. Regulatory defects in immunothrombosis are suspected to be a major factor in pathological thrombosis in forms such as disseminated intravascular coagulation (DIC) or deep vein thrombosis . DIC in sepsis is a prime example of both the dysregulated coagulation process as well as an undue systemic inflammatory response, resulting in

3640-437: The quality, effectiveness and efficiency of blood and transplant services. Its roles are stated to include: In 2009/10 its strategic objectives were focused on the efficient provision of a safe and sustainable supply of blood and its components, the identification and referral of more organ donors and the establishment of NHSBT as an effective and responsive organisation, focused on the needs of donors and patients. The year saw

3705-461: The same geographical area. Staff opposed this strategy. In July 2015 it was decided to shut the blood supply chain manufacturing facilities in Sheffield and Newcastle in 2017 and transfer their work to Manchester. Blood donation vehicles are allowed the use of blue lights and sirens (known commonly " blues and twos ") for the use of emergency blood transports. In some cases this will also require

3770-691: The subendothelial collagen by von Willebrand factor (VWF), which these cells produce. VWF is also stored in the Weibel-Palade bodies of the endothelial cells and secreted constitutively into the blood. Platelets store vWF in their alpha granules. When the endothelial layer is disrupted, collagen and VWF anchor platelets to the subendothelium. Platelet GP1b-IX-V receptor binds with VWF; and GPVI receptor and integrin α2β1 bind with collagen. The intact endothelial lining inhibits platelet activation by producing nitric oxide , endothelial- ADPase , and PGI 2 (prostacyclin). Endothelial-ADPase degrades

3835-487: The surface area; early dendritic , an octopus with multiple arms and legs; early spread , an uncooked frying egg in a pan, the "yolk" is the central body; and the spread , a cooked fried egg with a denser central body. These changes are all brought about by the interaction of the microtubule/actin complex with the platelet cell membrane and open canalicular system (OCS), which is an extension and invagination of that membrane. This complex runs just beneath these membranes and

3900-440: The thrombosis site. Platelet concentration in the blood (i.e. platelet count), can be measured manually using a hemocytometer , or by placing blood in an automated platelet analyzer using particle counting, such as a Coulter counter or optical methods. Most common blood testing methods include platelet count in their measurements, usually reported as PLT . Platelet concentrations vary between individuals and over time, with

3965-409: The thrombus. They are able to recognize and adhere to many surfaces, including bacteria, and can envelop them in their open canalicular system (OCP), leading to a proposal to name the process as covercytosis (OCS) rather than phagocytosis, as OCS is merely an invagination of outer plasma membrane. These platelet-bacteria bundles provide an interaction platform for neutrophils that destroy bacteria using

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4030-477: The use of a police escort for the transporting vehicle in order to safely and quickly navigate major road junctions. Escort is normally provided by several motorbike units. The service depends entirely on voluntary donations from the public. Originally, blood was collected from various donor clinics located over the country. In 1994, the first mobile session was held in Elstree, hosted by The Joely Bear Appeal . In

4095-493: The velocity of blood flow (i.e. shear range). Platelets have a central role in innate immunity , initiating and participating in multiple inflammatory processes, directly binding and even destroying pathogens. Clinical data show that many patients with serious bacterial or viral infections have thrombocytopenia , thus reducing their contribution to inflammation. Platelet-leukocyte aggregates (PLAs) found in circulation are typical in sepsis or inflammatory bowel disease , showing

4160-442: Was developed as a test of platelet function by Duke in 1910. Duke's test measured the time taken for bleeding to stop from a standardized wound in the ear lobe that was blotted every 30 seconds, considering less than 3 minutes as normal. Bleeding time has low sensitivity and specificity for mild to moderate platelet disorders and is no longer recommended for screening. In multiple electrode aggregometry , anticoagulated whole blood

4225-653: Was established at Southmead Hospital in Bristol. The National Organ Matching and Distribution Service was founded in 1972 and the two organisations merged in 1979 to form the UK Transplant Service. In 1991 the UK Transplant Service became an NHS special health authority and was renamed the United Kingdom Transplant Support Service Authority. It moved to purpose-built accommodation at Stoke Gifford , in

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