ISSN:1424-8832    

DOI:10.1159/000214160

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

This is a brief review of the major events which take place when plasmin reacts with fibrinogen (fibrinogenolysis) and fibrin (fibrinolysis). An effort is made to interrelate the locations of the major products of fibrinogenolysis (X, Y, D and E) in the originating fibrinogen molecule. The complexity of the lysates of fibrins, cross-linked by factor XIII to varying extents, is discussed. Clinical and structural implications of two fragments (D dimer and the D dimer-E complex) unique to cross-linked fibrin digests, are highlighted.

ISSN:1424-8832    

DOI:10.1159/000214161

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

This review summarises evidence supporting the view that the therapeutic anticoagulant properties of heparin are related to its physiological function in the organism, especially its activation of lipoprotein lipase and lecithinase. The conflicting results obtained from studies of the effect of heparin on platelet function are discussed, together with reasons for these differences of opinion. Finally, a hypothesis which links heparin, heparin-activated enzymes and platelet function is proposed, this hypothesis being complementary to the current views concerning the activation by heparin of the inhibitor of activated factor X.

ISSN:1424-8832    

DOI:10.1159/000214162

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Antibodies were raised in rabbits against purified human factor XII and insolubilized on Sepharose. This preparation of insolubilized anti-factor XII antibody was used to prepare factor-XII-free human platelet-rich and platelet-poor plasma for use in the study of platelet coagulant activities.

ISSN:1424-8832    

DOI:10.1159/000214163

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Washed platelets were ruptured by freezing and thawing; a coagulant activity was released which would correct the clotting time of factor XI (FXI)-deficient plasma only in the presence of kaolin. Platelets from a FXI-deficient patient treated in a similar fashion also released a coagulant activity which could be absorbed onto Sepharose-heparin and eluted similarly to plasma FXI.Collagen was employed to induce a coagulant activity in platelet-poor plasma (PPP) and platelet-rich plasma (PRP) in the presence and absence of antibodies developed to purified FXI and FXII. The presence of FXII antibody had little effect on the activity induced in PRP. However, the presence of FXI antibody eliminated the difference between PPP and PRP. An activity was induced when FXI-deficient PRP was incubated with collagen and none with PPP. One type of collagen failed to induce a coagulant activity.

ISSN:1424-8832    

DOI:10.1159/000214164

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The chemical characteristics of several PF4 preparations have been examined by gel electrophoresis, amino acid analysis and NH2-terminal amino acid sequence determination. Preparations of PF4 from gel filtration and from affinity chromatography appeared identical. A single NH2-terminal sequence was determined as follows: NH2-Glu-Ala-Glu-Glu-Asp-Gly-Asp-Leu-Gln-SCMCys-Leu-SCMCys-Val-Lys-Thr-Thr-Ser-Gln-Val-Arg-. The molecular weight of the PF4 subunits, which seem to be identical, was 7,100 based on the recovery of NH2-terminal glutamic acid.

ISSN:1424-8832    

DOI:10.1159/000214165

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The mechanism of activation of platelets by collagen was examined. Hirudin interfered with the initial collagen-platelet interaction and both hirudin and heparin inhibited collagen-induced release of platelet granular contents. Hirudin completely inhibited the release of both [3H]5HT and β-glucuronidase whereas heparin completely inhibited release of β-glucuronidase but only partly inhibited release of [3H] 5HT. β-glucuronidase and maximal [3H]5HT were only released when plasma was present. The results are compatible with an essential intermediary role for thrombin in collagen activation of platelets. Evidence was also obtained that von Willebrand factor may participate in this reacti

ISSN:1424-8832    

DOI:10.1159/000214166

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Seven laboratories collaborating in a study of two intermediate purity plasminogen preparations (64/23, 63/6) observed that the amount of activator (urokinase or streptokinase) and the time of activation of plasminogen influenced the amount of plasmin generated. Using casein and a synthetic polypeptide (S-2251) as substrates, the authors subsequently showed that complete activation of plasminogen was difficult to achieve without activity losses due to plasmin autodigestion. Comparison of the polypeptide subunits (on SDS electrophoresis) of the various plasminogen activation mixtures with their plasmin activity allowed the conclusion that at maximum generation of plasmin from plasminogen, some plasminogen remains in the form of an inactive plasminogen intermediate (PLG-i).

ISSN:1424-8832    

DOI:10.1159/000214167

出版商:S. Karger AG    

年代:1977

数据来源: Karger