ISSN:1424-8832    

DOI:10.1159/000215061

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

A sensitive micromethod for estimating the activated partial thromboplastin time in diluted capillary blood with excellent reproducibility is presented, as are results of test conditions with regard to sampling, calcium concentration, osmolarity of the diluent and the influence of the packed cell volume.

ISSN:1424-8832    

DOI:10.1159/000215062

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

In 30 subjects on stabilized oral anticoagulant treatment, factor VII activity (VII:C) and factor VII antigen (VIl·Ag) were evaluated. The average VII:C and VIl·Ag levels were 8.7 and 30.7, respectively. All plasma samples were treated with 1 M barium chloride: all the activity and a corresponding average amount of antigen were adsorbed by the salt. The cold-promoted activation of factor VII was found in 5/30 subjects. Corresponding amounts of VII:C and VII: Ag were also removed from the plasma of these subjects after cold activation following the addition of barium chloride. It clearly results from these studies that a portion of VIl·Ag cannot be adsorbed by barium chloride because of a reduction (or a lack) of the γ-carboxyglutamic groups. This portion of VIl·Ag can therefore be identified as Pivka

ISSN:1424-8832    

DOI:10.1159/000215063

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

A case of factor VII deficiency in a 52-year-old woman who developed central nervous system hemorrhage is here reported. Screening coagulation tests were all normal except for prothrombin time, normotest and thrombotest. Specific assays of vitamin Independent factors revealed that factor VII activity was reduced (11 U/dl). The studies of the family demonstrated that 2 sisters out of 4 were heterozygous for the defect. The activity of factor VII in the offspring, classified as obligatory carriers, ranged between 62 and 78 U/dl, the antigen between 55 and 75 U/dl. The wide variability of factor VII in normal people and the possible compensative effect of normal alleles in carriers do not allow to define the variant, namely if the patient is a CRMR homozygote or a CRMR/CRM- double heterozygote.

ISSN:1424-8832    

DOI:10.1159/000215064

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

We report the successful treatment of a 5 5-year-old man with an acquired factor VIII inhibitor, the appearance of which followed surgery for a carcinoma of the biliary tract. The patient, who had recurrent life-threatening bleeding episodes, was treated with intensive plasmapheresis, factor VIII concentrates, azathioprine and methylprednisolone. Disappearance of the inhibitor was observed after the second series of plasma exchanges. Controls 2 and 3 months after treatment confirmed the complete absence of the inhibitor and normal levels of factor VIII. The crucial role of plasma exchange is considered and discussed.

ISSN:1424-8832    

DOI:10.1159/000215065

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

Spectrophotometric heparin assays are expected to be independent on clotting factors, either activated or nonactivated, but could be sensitive to heparin neutralization during blood collection. Is was shown that more than 200 U of heparin/1 plasma can completely be neutralized during blood processing. Because the heparin neutralization is not constant but dependent on the sample as well as on the type of sample handling, one cannot beforehand compensate and correct the results for possible heparin neutralization. We tested the use of pyridoxal 5’-phosphate (PLP) to prevent heparin neutralization. As the use of PLP in the citrate tube decreased the heparin neutralization to a negligible effect, PLP-citrate tubes are to be preferred for all plasma heparin determination

ISSN:1424-8832    

DOI:10.1159/000215066

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

Alterations of platelet function and blood coagulation may occur with exercise or β-adrenoceptor blockade. To determine if β-blockade could modify exercise-induced changes in haemostatic factors we performed a double-blind study of actue strenuous exercise in normal males with and without β-blockade. Exercise increased prostacyclin and plasminogen activator levels but there was no evidence of thrombin generation as indicated by unchanged platelet aggregation responses, β-thromboglobulin and íibrinopeptide A levels. The only alteration in coagulation by β-blockade was a reduction in the factor VIII:C and VIII:RAg rise after exercise and this modification may be relevant to the protective effect of these drugs in patients with coronary artery di

ISSN:1424-8832    

DOI:10.1159/000215067

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

Employing immunofluorescent staining methods, platelets from several adult patients with chronic idiopathic thrombocytopenic purpura, with systemic lupus erythematosus, and with classical rheumatoid arthritis stained positively with antisera to C3(β1C and C3dg(α2D). In some cases, platelet-bound C3dg antigens, but no evidence of other C3 antigens were observed. Platelets that were positive for C3 and/or C3dg were always positive for IgG or for both IgG and IgM. Platelets from normal subjects stained negatively for C3, C3dg, IgG, and IgM. Furthermore, various incubation experiments were performed to investigate the uptake of C3 and its subfragments on normal platelets. Positive platelet staining for C3 was obtained after incubation with normal and C3b-containing sera, but not after incubation with native C3. Platelets incubated with C3c(β1A)/C3dg-containing serum gave a positive staining for C3dg, but not for C3c. None of the sera stained positively for IgG or IgM. Thus, in contrast to platelets from several of the patients, no in vivo binding of C3 antigens on normal platelets could be established. However, in vitro they could take up both C3b and C3dg, apparently by specific binding to platelet surface structur

ISSN:1424-8832    

DOI:10.1159/000215068

出版商:S. Karger AG    

年代:1984

数据来源: Karger

摘要:

Different, tissue-dependent antiaggregatory properties of endothelial cells are suggested by in vitro findings, which show different spectra and amounts of arachidonic acid products to be synthesized by vessels of different type and origin. Platelet aggregation was assessed in vivo in native arterioles of the hamster cheek pouch and in arterioles of heart transplants by intravascular excitation of fluorescein isothiocyanatedextran (FITC-d). The time to aggregate appearance (TAA) was determined, i.e. the interval from onset of FITC-d excitation until the first aggregate was seen to adhere to the vessel wall. Two groups were pretreated with 100 μg/kg nafazatrom and 100 mg/kg acetylsalicylic acid (ASA), both potent antithrombotic drugs. Nafazatrom has been shown to stimulate prostacyclin release from endothelial cells, whereas ASA blocks cyclooxygenase both in platelets and vessel walls. TAA was the same for native arterioles of both types. Nafazatrom was equally effective in both vessels, and about three orders of magnitude more potent than ASA in prolonging TAA. ASA was twice as effective in arterioles of the heart as it was in those of the skin type, indicating that tissue-dependent mechanisms achieve the antiaggregatory potency of the vessel walls. It is concluded that further in vivo studies on platelet aggregation and thrombus formation should be performed on cardiac vessels directly and not on vessels of different origin. The presented model may be a useful tool for investigating the mentioned tissue-dependent mechanisms of thrombus formation in vivo

ISSN:1424-8832    

DOI:10.1159/000215069

出版商:S. Karger AG    

年代:1984

数据来源: Karger

ISSN:1424-8832    

DOI:10.1159/000215070

出版商:S. Karger AG    

年代:1984

数据来源: Karger