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1.
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections.  相似文献   
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赛赓啶对 KBV200细胞多药抗性的逆转作用   总被引:3,自引:0,他引:3  
研究赛赓啶对KBV200细胞多药抗性的逆转作用及逆转机制。在KBV200细胞,采用MTT法,测出赛赓啶对长春新碱、阿霉素和鬼臼乙叉甙耐药的逆转系数分别为5.5,2.0和1.9,而对5-氟尿嘧啶、美法仑的细胞毒性作用无明显影响,表明赛赓啶为多药抗性逆转剂。荧光分光光度法测定表明,赛赓啶可使KBV200细胞内阿霉素蓄积量增加。流式细胞荧光测定显示赛赓啶可增加罗丹明123的蓄积并减慢其外排。免疫细胞化学及狭缝杂交表明赛赓啶不影响KBV200细胞的P-糖蛋白染色深度和 mdr1 RNA 表达水平。以上结果提示赛赓啶的多药抗性逆转机制是抑制P-糖蛋白泵的功能。  相似文献   
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Zusammenfassung Die Pneumatosis cystoides intestinii (PCI), das Auftreten submuköser oder subseröser, gasgefüllter Zysten in der Wand des Gastrointestinaltrakts, tritt als seltene Erkrankung ohne eindeutige Geschlechtspräferenz vorwiegend in der 3. bis 5. Lebensdekade auf. Atiopathogenetisch werden unterschiedliche Faktoren diskutiert, am wahrscheinlichsten ist eine bakterielle Ursache (Clostridium perfringens) in Verbindung mit einer minimalen Unterbrechung der Mukosaintegrität. Eine pathognomonische Symptomatik gibt es nicht, das klinische Bild reicht von asymptomatischen Zufallsbefunden bis zur Hämatochezie. Die Diagnose wird durch den Nachweis der Gaseinschlüsse mittels Abdomenübersichtsaufnahme und Kolonkontrasteinlauf gestellt. Als Behandlungsmethoden für symptomatische Patienten stehen Sauerstofftherapie, Antibiotikagabe (Metronidazol) und in schweren Fällen die Resektion des betroffenen Darmabschnitts zur Verfügung.
Pneumatosis cystoides intestinalis (PCI), a condition involving submucosal or subserosal gas-containing cysts of the wall of the gastrointestinal tract, is a rare entity. It is mostly diagnosed between the third and fifth decades of life without a clear sexual predominance. Different aetiopathogenetic factors are under discussion, the most probable being a bacteriologic cause (Clostridium perfringens) in combination with minimal leaks in mucosal barrier. There are no pathognomonic symptoms; the clinical picture ranges from incidental findings to haematochezia. Diagnosis is based on plain abdominal film and X-ray following barium enema. Methods of treatment in symptomatic cases are oxygen and antibiotic (metronidazole) therapies and, in severe cases, resection of the diseased part of the intestine.
  相似文献   
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华蟾蜍毒素对离体豚鼠输精管的作用   总被引:3,自引:0,他引:3  
韩永晶  张力  崔荣芬 《药学学报》1992,27(4):252-255
华蟾蜍毒素(华蟾素)使离体豚鼠输精管产生剂量依赖性收缩反应,利血平化豚鼠输精管及冷藏输精管对华蟾素反应减弱。给酚妥拉明、维拉帕米后,输精管对华蟾素反应均受抑制,溴苄胺可使反应潜伏期缩短。结果提示华蟾素收缩输精管反应可能与其促进肾上腺素能神经末稍NA释放有关。  相似文献   
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In the Netherlands, prepubertal girls have been vaccinated against rubella since 1974 (the UK strategy). Recently the Dutch Health Council advocated the introduction of an elimination strategy: vaccination of 1- and 9-year-old children. Dynamic effects of both strategies are studied using deterministic and stochastic models. Estimates of several epidemiological parameters are given. All computations and simulations were performed using as much field data as possible. Under the old strategy a new equilibrium is expected around the years 1995 to 2000; the new strategy is estimated to eliminate rubella (CRS) in large parts of the population 3 to 5 years after its initiation. Possible consequences of the new strategy on a cluster of people who refuse vaccination are investigated.  相似文献   
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Intelligence in 20 presymptomatic subjects with an increased risk (> 95%) for carrying the gene for Huntington's disease (HD) was studied in a prospective, case-control, single blind study. No significant differences between the groups were detected for intelligence indices and subtest scores (Wechsler Adult Intelligence Scale). The high level of the performance IQ and the significant discrepancy between performance IQ and verbal IQ found in both the high risk and the low risk groups contrasted with our expectations based on anamnestic information, general clinical opinion, and the results of previously conducted studies. We propose that psychosocial circumstances could explain the test results and discuss the consequences of our findings for clinical genetics practice.  相似文献   
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BACKGROUND: The role of neutralizing antibody (NAb) in determining response to antiviral therapy has not been established. OBJECTIVE: In this study we have analysed the kinetic's of the NAb response in patients with chronic hepatitis C who received antiviral therapy. STUDY DESIGN: Seventeen patients infected with genotype 1, 2a/c or 3a hepatitis C virus (HCV) were enrolled, eight with a sustained virological response (SVR), five non-responders and four relapsers. RESULTS: The mean NAb titre required to neutralize 50% of the E1E2-pp in patients who achieved an SVR (294+/-S.D. 51), in relapsers (246+/-S.D. 61.7) and non-responders (286+/-S.D. 80.95) did not differ significantly between the patient groups and did not alter during the course of treatment (P>0.01). Genetic variation present before antiviral therapy was analysed by single strand conformation polymorphism (SSCP) and failed to demonstrate a significant difference in the mean number of amplified E1E2 DNA fragments from the serum of patients who achieved an SVR (3.15+/-S.D. 1.53), relapsers (2.8+/-S.D. 1.32) or non-responders (3.69+/-S.D. 1.75). The baseline serum HCV viral loads were also not significantly different between patients who achieved an SVR (1.4 x 10(6) copies/ml; +/-S.D. 2.4 x 10(6)), relapsers (1.3 x 10(7) copies/ml; +/-S.D. 2.4 x 10(7)) and non-responders (1.5 x 10(6) copies/ml; +/-S.D. 1.1 x 10(6)). CONCLUSION: We have shown that neutralizing anti-HCVpp antibody is not associated with response to antiviral therapy. In addition, there was no correlation between baseline virological load, circulating viral quasi-species, NAb titres and final response to treatment.  相似文献   
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Hepatitis B virus (HBV) is one of the major causative agents of chronic liver diseases in Korea. HBV has been classified into 8 genotypes by a divergence of >8% in the entire genomic sequence, and have distinct geographic distributions. There are limited data on the relevance between HBV genotypes and clinical outcomes in Korea. To investigate the clinical feature relating to HBV genotype in Korea, a total 120 serum samples with HBsAg (65 from Seoul and 55 from the other city in Korea) were obtained from each 30 chronic HBV carriers with asymptomatic carrier (ASC), chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). HBV genotype was determined by either enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies against genotype-specific epitopes in the preS2-region or the direct sequencing of small S gene. HBV genotypes were determined in 105 (87.5%) of 120 samples. HBV genotype C was identified in all HBV carriers with ASC, CH, LC, and HCC. Genotypes A, B, D, E, F and G were not detected in any of them. Genotype C HBV prevails predominantly among chronic carriers of the virus in Korea, irrespective of their clinical stages of liver disease and geographic origin.  相似文献   
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