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The extracellular domain of the TSH receptor (TSHR-561, amino acids #78-389) was expressed as a hexa-histidine fusion protein in bacteria. The recombinant protein was purified to homogeneity and used to immunize porcine and ovine species. High titre antibodies were obtained from both species that recognized the recombinant protein in Western blot analysis but failed to interfere with the TSH radio receptor assay. An epitope library was constructed and screened with affinity purified ovine and porcine antisera and defected a number of positive clones. Sequence analysis revealed that all of the epitopes contained sequences derived from the carboxyl terminus of the recombinant immunogen. One clone defined an epitope covering 16 amino acids from the carboxyl terminus and was the common epitope found in all of the other clones. Western blot screening of a large panel of Graves' sera with recombinant TSH receptor protein identified one patient sera that also recognized linear epitopes in the TSHR-561 protein. Experimentation demonstrated that the linear epitope recognized by this human sera was identical to the sequence recognised by the animal antisera. This sequence is unique to the TSH receptor and will be useful in further studies to analyze the TSH receptor protein © 1996 Wiley-Liss, Inc.  相似文献   
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We report the emergence of vancomycin resistance in a patient colonized with a vanA-containing, vanRS-negative isolate of Enterococcus faecium which was initially vancomycin susceptible. This is a previously undescribed mechanism of drug resistance with diagnostic and therapeutic implications.  相似文献   
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The recovery of Clostridium difficile from the stools of patients with C. difficile-associated diarrhea was evaluated by use of an enrichment broth (cycloserine-cefoxitin fructose broth supplemented with 0.1% sodium taurocholate [TCCFB]) and was compared to that from selective agar (cycloserine-cefoxitin fructose agar [CCFA]) and alcohol shock followed by inoculation onto blood agar (AS-BA). TCCFB was superior to CCFA and AS-BA, and neither the storage time nor the storage temperature affected the recovery rate.  相似文献   
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There is no uniformly accepted method for detecting colonization with vancomycin-resistant enterococci (VRE). The sensitivities of five culture methods were determined for patients known to harbor VRE. Of 189 inpatients, 101 were found to harbor VRE by at least one method. Three methods detected fewer than half of the cultures. Campylobacter agar identified 70% of patients. Enterococcosel broth (containing vancomycin and aztreonam) identified 88% and may be preferred over other media for routine surveillance.  相似文献   
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Clostridium difficile is the bacterium most commonly surmised to cause antimicrobial- and hospital-associated diarrhea in developed countries worldwide, and such infections are thought to be increasing in frequency and severity. A laboratory-based study was carried out to characterize C. difficile strains isolated from persons in Ontario, Canada, during 2004 to 2006 according to toxin type (enterotoxin A, cytotoxin B, and binary toxin [CDT]), tcdC gene characterization, ribotyping, pulsed-field gel electrophoresis, and toxinotyping. Clostridium difficile was isolated from 1,080/1,152 (94%) samples from 21 diagnostic laboratories. Isolates with toxin profiles A+ B+ CDT, A+ B+ CDT+, A B+ CDT, and A B+ CDT+ accounted for 63%, 34%, 2.4%, and 0.6% of isolates, respectively. Alterations in tcdC were detected in six different ribotypes, including ribotype 027. A total of 39 different ribotypes were identified, with ribotype 027/North American pulsotype 1 (NAP1), an internationally recognized outbreak strain associated with severe disease, being the second most common ribotype (19% of isolates). Transient resistance to metronidazole was identified in 19 (1.8%) isolates. While a large number of ribotypes were found, a few predominated across the province. The high prevalence and wide distribution of ribotype 027/NAP1 are disconcerting in view of the severity of disease associated with it.  相似文献   
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Medicinal plants based traditional systems of medicines are playing important role in providing health care to large section of population, especially in developing countries. Interest in them and utilization of herbal products produced based on them is increasing in developed countries also. To obtain optimum benefit and to understand the way these systems function, it is necessary to have minimum basic level information on their different aspects. Indian Systems of Medicine are among the well known global traditional systems of medicine. In this review, an attempt has been made to provide general information pertaining to different aspects of these systems. This is being done to enable the readers to appreciate the importance of the conceptual basis of these system in evolving the material medica. The aspects covered include information about historical background, conceptual basis, different disciplines studied in the systems, Research and Development aspects, Drug manufacturing aspects and impact of globalization on Ayurveda. In addition, basic information on Siddha and Unani systems has also been provided.  相似文献   
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Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
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