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Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.  相似文献   
85.
Cerebral venous thrombosis is an unusual condition characterized by headache, nausea, vomiting, focal deficits and epileptic seizures. In this case report we describe a patient who presented with headache and focal motor deficits after an uneventful Caesarean section, performed using combined spinal-epidural anaesthesia. Magnetic resonance imaging was performed because of the pronounced neurological symptoms, and a diagnosis of cerebral venous thrombosis was made. The patient was treated with anticoagulant agents and made a complete recovery. This case emphasizes the importance of considering cerebral venous thrombosis in the differential diagnosis of headache in the post-partum period prior to instituting conventional therapy.  相似文献   
86.
目的探讨慢性萎缩性胃炎诊治问题及策略方法。方法结合现代医学病因治疗研究进展,应用中医因机证治,整体和微观辨证结合研究方法,治疗慢性萎缩性胃炎。结果中医整体和微观辨论证结合方法,能阻断或逆转部分肠上皮化生和异型增生,使药物预防胃癌成为可能。结论中西医结合治疗慢性萎缩性胃为有效治疗方法。  相似文献   
87.
BACKGROUND: Randomised controlled trials have shown the efficacy of several treatment modalities for lower urinary tract symptoms (LUTS) in selected populations. The effectiveness in daily practice has hardly been investigated, especially in primary care and is dependent on choices between all possible treatment options and best investigated in a comprehensive study, including all treatment modalities (watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors, and surgery). AIM: Assessment of the effectiveness of a comprehensive treatment protocol for LUTS in primary care. DESIGN OF STUDY: Randomised controlled trial. SETTING: Fourteen general practices in the Netherlands. METHOD: Intervention: treatment protocol based on a formalised expert opinion. Control condition: usual care. Study population: 208 subjects with moderate to severe LUTS (IPSS > or =8, median = 13). OUTCOME MEASURES: symptom severity (IPSS [International Prostate Symptom Score]), bother score (Dan-PSS [Danish Prostate Symptom Score]), and maximum urinary flow (Q(max)); incidence of acute urinary retention and urinary tract infections. RESULTS: In the intervention group markedly more subjects used an alpha-blocker at end of follow-up than in the usual care group (24% versus 6%). No significant differences were found between intervention and control group in IPSS, Q(max) or Dan-PSS. CONCLUSION: alpha-blockers and watchful waiting are the most frequent treatment modalities for LUTS in primary care. Our study showed no evidence that a protocol using well-defined indications for all possible treatment modalities based on a formalised expert opinion procedure has added value. Based on our results, we cannot recommend a broadening of the indication for alpha-blockers, which, however, seems to be the current trend.  相似文献   
88.
Burren CP, Wanek D, Mohan S, Cohen P, Guevara-Aguirre J, Rosenfeld RG. Serum levels of insulin-like growth factor binding proteins in Ecuadorean children with growth hormone insensitivity. Acta Pædiatr 1999; Suppl 428: 185–91. Stockholm. ISSN 0803–5326
Although insulin-like growth factor binding proteins (IGFBPs) are known to be important modulators of the action of insulin-like growth factors (IGFs), regulation of their production in vivo is not completely understood. Serum concentrations of IGFBP-3, -4 and -5 and acid-labile subunit (ALS) were therefore examined in 20 children with growth hormone (GH) insensitivity before and after 6 months of therapy with recombinant human IGF-I (80 or 120 ug/kg twice daily). The IGFBP concentrations in these children were compared with those in 62 GH-deficient children receiving GH therapy for 3 months. Serum levels of IGFBP-3, -4 and -5 and ALS all increased significantly ( p < 0.0001) in GH-deficient children in response to GH therapy, whereas no significant increases occurred in the children with GH insensitivity. These findings indicate that GH is responsible for the regulation of serum levels of IGFBP-3, -4 and -5 and ALS, and that IGF-I does not directly regulate the concentrations of these circulating IGFBPs. □ Growth hormone, growth hormone insensitivity, insulin-like growth factor I, insulin-like growth factor binding protein  相似文献   
89.
 A method to obtain K. marxianus mutants has been developed. Different auxotrophic mutants were isolated by nystatin and snail-enzyme enrichment procedures using an incubation time of 2 h before adding the antibiotic or the enzyme respectively. All his mutants analyzed by complementation tests turned out to belong to the same complementation group. Some of them were transformed and complemented by the S. cerevisiae HIS3 gene. These non-reverting his3 mutants contain no heterologous sequence, which is essential to make them acceptable for application in the food industry. Received: 15 November/21 December 1995  相似文献   
90.
Heterozygous carriers of ATM (ataxia telangiectasia mutated gene) mutations have increased risk of breast cancer (BC). We have estimated the prevalence of mutations in the ATM gene among Spanish patients with early-onset BC. Forty-three patients diagnosed with BC before the age of 46 years, and negative for BRCA1 and BRCA2 mutations, were analysed for the presence of ATM mutations. A total of 34 ATM sequence variants were detected: 1 deleterious mutation, 10 unclassified variants and 23 polymorphisms. One patient (2.3%) carried the ATM deleterious mutation (3802delG that causes ataxia telangiectasia in the homozygous state) and 13 patients carried the 10 ATM unclassified variants. The truncating mutation 3802delG and eight of the rare variants were not detected in a control group of 150 individuals. Different bioinformatic sequence analysis tools were used to evaluate the effects of the unclassified ATM changes on RNA splicing and function protein. This in silico analysis predicted that the missense variants 7653 T>C and 8156 G>A could alter the splicing by disrupting an exonic splicing enhancer motif and the 3763 T>G, 6314 G>C, and 8156 G>A variants would affect the ATM protein function. These are the initial results concerning the prevalence of germline mutations in the ATM gene among BC cases in a Spanish population, and they suggest that ATM mutations can confer increased susceptibility to early-onset BC.  相似文献   
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