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A unique family with protein C (PC) deficiency is described. The proband had a history of renal vein thrombosis as a newborn and iliofemoral thrombosis at the age of 6 years. After 6 months of heparin treatment, discontinuation of anticoagulation therapy was accompanied by persistent hypofibrinogenemia with increased fibrinogen consumption. With continuous infusion of heparin, fibrinogen turnover normalized, and the child has remained free of thrombosis. Both the immunologic level of PC and the functional activity measured by amidolytic assay were moderately reduced (47% and 34%, respectively). Functional activity of PC measured by its anticoagulant activity was disproportionately lower (14%). A 3-year-old asymptomatic sibling had a similar disproportionate reduction of PC anticoagulant activity compared with the amidolytic activity or immunologic level. The mother demonstrated type I PC deficiency with a proportionate reduction in immunologic protein levels (59%), anticoagulant activity (52%), and amidolytic activity (46%), whereas the father had type II PC deficiency with normal immunologic protein levels (102%), normal amidolytic function (98%), but a low anticoagulant function (50%). An abnormal PC molecule was detected by two-dimensional immunoelectrophoresis in the father and two children. These data are consistent with the hypothesis that the children are doubly heterozygous for two different types of PC deficiency inherited from each of the parents. A 14-day trial of danazol in the proband resulted in a rise in the PC antigen concentration from 66% to 98% but no change in PC anticoagulant function.  相似文献   
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Peroxidase-H2O2-halide system: Cytotoxic effect on mammalian tumor cells   总被引:28,自引:0,他引:28  
Clark  RA; Klebanoff  SJ; Einstein  AB; Fefer  A 《Blood》1975,45(2):161-170
Myeloperoxidase, H2O2, and a halide constitute a potent antimicrobial system. A cytotoxic effect of this system on a line of mouse ascitic lymphoma cells (LSTRA) is demonstrated here using four different assay systems: 51Cr release, trypan blue exclusion, inhibition of glucose C-1 oxidation, and loss of oncogenicity for mice. Deletion of each component of the system, preheating the peroxidase, or addition of azide, cyanide, or catalase abolished the cytotoxicity. Myeloperoxidase was effective with either chloride or iodide as the halide, while lastoperoxidase was effective with iodide but not chloride. The iodinated thyroid hormones, triiodothyronine and thyroxine, could substitute for the halide, and H2O2 could be replaced by a peroxide- generating enzyme system such as glucose and glucose oxidase or by H2O2 producing bacteria such as pneumococci or streptococci. The possibility is raised that the peroxidases of inflammatory cells and certain biologic fluids may affect tumor initiation or growth in vivo.  相似文献   
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AIM: To assess the efficacy of hemoclip application in combination with epinephrine injection in the treatment of bleeding peptic ulcers and to compare the clinical outcomes between patients treated with such a combination therapy and those treated with epinephrine injection alone. METHODS: A total of 293 patients (211 males, 82 females) underwent endoscopic therapy for bleeding peptic ulcers. Of these, 202 patients (152 males, 50 females) received epinephrine injection therapy while 91 patients (59 males, 32 females) received combination therapy. The choice of endoscopic therapy was made by the endoscopist. Hemostatic rates, rebleeding rates, need for emergency surgery and 30-d mortality were the outcome measures studied. RESULTS: Patients who received combination therapy were significantly older (mean age 66±16 years, range 24-90 years) and more suffered from chronic renal failure compared to those who received epinephrine injection therapy alone (mean age 61±17 years, range 21-89 years). Failure to achieve permanent hemostasis was 4% in the group who received epinephrine injection alone and 11% in the group who received combination therapy. When the differences in age and renal function between the two treatment groups were taken into account by multivariate analysis, the rates of initial hemostasis, rebleeding rates, need for surgery and 30-d mortality for both treatment options were not significantly different. CONCLUSION: Combination therapy of epinephrine injection with endoscopic hemoclip application is an effective method of achieving hemostasis in bleeding peptic ulcer diseases. However, superiority of combination therapy over epinephrine injection alone, could not be demonstrated.  相似文献   
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Fleischman  RA 《Blood》1988,71(3):800-803
The leukemias induced by the Friend polycythemia virus and other leukemogenic retroviruses have previously not been transplantable until weeks or months after virus inoculation. Because tumor-specific immune mechanisms persist in both irradiated and nude mice, it has not been possible to determine if this result is due to rejection of cells already immortalized by retrovirus infection, or reflects an inherent limitation in the proliferative capacity and malignancy of these "preleukemic" cells. To clarify these issues, we have transplanted virus-infected bone marrow into mouse fetuses that are immunologically immature and thus incapable of graft rejection. We report here that within days of virus inoculation, transplantable cells capable of disease progression in certain fetal hosts can be detected with this technique. These results demonstrate that cells with the capacity for extensive leukemic proliferation arise very early in Friend virus- induced disease. However, successful transplantation was seen only in genetically anemic recipients (Wx/Wv), which are deficient in hematopoietic stem cells, and not in their normal littermates. Thus, in accord with recent in vitro observations, this in vivo data suggests that normal hematopoietic cells, independent of immune mechanisms, can suppress the malignant progression of transformed cells.  相似文献   
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Background and Aim: Environmental factors such as food, lifestyle and prevalence of Helicobacter pylori infection are widely different in Asian countries compared with the West, and physiological functions and genetic factors of Asians may also be different from those of Westerners. Establishing an Asian consensus for functional dyspepsia is crucial in order to attract attention to such data from Asian countries, to articulate the experience and views of Asian experts, and to provide a relevant guide on management of functional dyspepsia for primary care physicians working in Asia. Methods: Consensus team members were selected from Asian experts and consensus development was carried out by using a modified Delphi method. Consensus teams collected published papers on functional dyspepsia especially from Asia and developed candidate consensus statements based on the generated clinical questions. At the first face‐to‐face meeting, each statement was reviewed and e‐mail voting was done twice. At the second face‐to‐face meeting, final voting on each statement was done using a keypad voting system. A grade of evidence and strength of recommendation were applied to each statement according to the method of the GRADE Working Group. Results: Twenty‐nine consensus statements were finalized, including seven for definition and diagnosis, five for epidemiology, nine for pathophysiology, and eight for management. Algorithms for diagnosis and management of functional dyspepsia were added. Conclusions: This consensus developed by Asian experts shows distinctive features of functional dyspepsia in Asia and will provide a guide to the diagnosis and management of functional dyspepsia for Asian primary care physicians.  相似文献   
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