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排序方式: 共有1016条查询结果,搜索用时 15 毫秒
1.
BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.  相似文献   
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Molecular genetic characterization of XRCC4 function   总被引:2,自引:0,他引:2  
XRCC4 is a generally expressed protein of 334 amino acids that is involved in the repair of DNA double-strand breaks and in V(D)J recombination, but its function is unknown. In this study, we have used a mutational approach and the yeast two-hybrid method to perform an initial characterization of this protein. We show that the XRCC4 protein is located in the nucleus. We also demonstrate that several potential phosphorylation sites are not required for XRCC4 function in a transient V(D)J recombination assay. In addition, we show that XRCC4 forms a homodimer in vivo with the homodimerization domain being located within amino acids 115-204. Finally, we define a core domain of XRCC4 that functions in V(D)J recombination and comprises amino acids 18-204. Potential functions of XRCC4 are discussed.   相似文献   
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Toxin B (TcdB), a major Clostridium difficile virulence factor, glucosylates and inactivates the small GTP-binding proteins Rho, Rac, and Cdc42. In the present study we provide evidence that enzymatically inactive fragments of the TcdB enzymatic domain are effective intracellular inhibitors of native TcdB. Site-directed and deletion mutants of the TcdB enzymatic region (residues 1 to 556), lacking receptor binding and cell entry domains, were analyzed for attenuation of glucosyltransferase and glucosylhydrolase activity. Five of six derivatives from TcdB(1-556) were found to be devoid of enzymatic activity. In order to facilitate cell entry, mutants were genetically fused to lfn, which encodes the protective antigen binding region of anthrax toxin lethal factor and mediates the cell entry of heterologous proteins. In line with reduced enzymatic activity, the mutants also lacked cytotoxicity. Remarkably, pretreatment or cotreatment of cells with four of the mutants provided protection against the cytotoxic effects of native TcdB. Furthermore, a CHO cell line expressing enzymatically active TcdB(1-556) was also protected by the mutant-derived inhibitors, suggesting that inhibition occurred at an intracellular location. Protection also was afforded by the inhibitor to cells treated with Clostridium sordellii lethal toxin (TcsL), which uses the same cosubstrate as TcdB but shares Rac only as a common substrate target. Finally, the inhibitor did not provide protection against Clostridium novyi alpha-toxin (Tcnalpha), which shares similar substrates with TcdB yet uses a different cosubstrate. This is the first report to demonstrate that the potential exists to inhibit toxins at their intracellular site of action by using inactive mutants.  相似文献   
4.
During the course of an experimentally induced Ebola virus (EBOVA) infection of cynomolgus macaques, peripheral blood mononuclear cells were isolated and characterized by multi-color flow cytometry. Both CD4+ and CD8+ lymphocyte counts decreased 60-70% during the first 4 days after infection. Among CD8+ lymphocytes, this decline was greatest among the CD8(lo) population, which was composed mostly of CD3- CD16+ NK cells. In contrast, the number of CD20+ B lymphocytes in the blood did not significantly change during the course of the infection. Phenotypic analysis of T lymphocyte subsets by flow cytometry failed to show evidence of a robust immune response to the infection. Apoptosis could be detected as early as day 2 postinfection among the CD8+ and CD16+ subsets of lymphocytes. Increased expression of CD95 (Fas) suggests that apoptosis may be induced via signaling through the Fas/Fas-L cascade. In contrast, the number of HLA-DR+ cells increased tenfold in the blood during the course of infection. These data suggest that EBOV may block dendritic cell maturation after infection, thereby inhibiting activation of lymphocytes and eliminating those subsets that are most likely to be capable of mounting an effective response to the virus.  相似文献   
5.
The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
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Disseminated Klebsiella rhinoscleromatis infection   总被引:1,自引:0,他引:1  
A 35-year-old obese black American woman presented with nausea, vomiting, diarrhea, fever, cough, and chest pain of 2 weeks duration. She was pancytopenic and acidotic, with respiratory failure and hypotension. A diagnosis of septic shock was made, and the patient died 48 hours after admission. Blood cultures were positive for organisms that were reported to be Klebsiella rhinoscleromatis. At autopsy she had massive hepatic necrosis with numerous Mikulicz's cells. The lungs, spleen, and bone marrow were also involved. To our knowledge, this is the first report of a case of systemic infection with K rhinoscleromatis.  相似文献   
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