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Retrospective analysis of the Beijing family of Mycobacterium tuberculosis in preserved lung tissues
L Qian JD Van Embden AG Van Der Zanden EF Weltevreden H Duanmu JT Douglas 《Canadian Metallurgical Quarterly》1999,37(2):471-474
Direct repeat spoligotyping of 85 paraffin-embedded lung biopsies was used to investigated the occurrence around Beijing of the Beijing family of Mycobacterium tuberculosis. Samples ranged in time from 1956 to 1990. Hybridization patterns were found with 49 (58%) samples, and 45 (92%) produced typical Beijing family patterns extending over the 34-year period. 相似文献
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This paper summarizes the developmental stages of the baboon during the period of organ formation and provides comparative information for other primates, including the human. Special attention is directed to the early development of the nervous system, eye, ear and nose/palate. The similarity in development of these structures with humans indicates that the baboon is a suitable model for studies of normal and abnormal neurological development. Spontaneous prenatal loss rates in the baboon (2.4-11.2%) are slightly lower than those reported in rhesus and cynomologus monkeys. The baboon, in addition to the cynomologus monkey and macaque, has been used as a model in teratology research to assess the potential risk of thalidomide, sex steroids, Bendectin and rubella virus, as well as to study the pathogenesis of malformations associated with the corticosteroid triamcinolone acetonide. The rate of spontaneous malformations (<1%) in baboons, similar to that reported for other commonly used primates, supports their continued use as a teratological model. In this regard, a sample protocol is provided for the safety evaluation of biotechnology products using nonhuman primates, which are the most appropriate model for those compounds which are bioactive in species closely related to humans. 相似文献
126.
The paper presents 30-year experience in treating 158 patients with congenital cystic diseases of the liver and bile ducts. Depending on the pattern of hepatobiliary lesions, the diagnostic value of techniques, such as ultrasound, computerized tomography, scintigraphy of the liver duodenoscopy with THCG was defined. Analyzing the late outcomes provided recommendations for the most optimal surgical management: cystic fenestration and tunneling in hepatic polycystosis, pericystectomy in solitary cysts of the liver, different varieties of bile draining operations in choledochal cysts and Caroli's disease. 相似文献
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Many G protein alpha subunits are dually acylated with myristate and palmitate or are palmitoylated on more than one cysteine residue near their N termini. The Galpha protein that activates adenylyl cyclase, alphas, is not myristoylated but can be reversibly palmitoylated. It appears that alphas contains another, as-yet-unidentified covalent modification that decreases its apparent dissociation constant for adenylyl cyclase from 50 nM to <0. 5 nM. This modification is at or near the N terminus of the protein and is hydrophobic. Palmitoylation of native alphas does not account for its high affinity for adenylyl cyclase. 相似文献
129.
J Sauleda A Maimó M Riera J Ramírez B Togores S Pons A Payeras AG Agusti 《Canadian Metallurgical Quarterly》1997,91(9):530-536
The aim of the present study was to evaluate in HIV-positive patients with bacterial pneumonia, the diagnostic value of a new endoscopic technique that uses a single catheter to perform a telescopic plugged catheter (TPC) followed by a modified protected bronchoalveolar lavage (mpBAL). Fifty-eight HIV-positive patients with respiratory infection were included in the study. Samples from TPC and mpBAL were cultured quantitatively. Standard bronchoalveolar lavage was performed to rule out opportunistic infections. According to the clinical and microbiological results, patients were classified in the study group (27 with bacterial pneumonia) or the control group (31 without bacterial pneumonia). Sensitivity of TPC was 56% [95% confidence intervals (CI) 37-75%] and its specificity was 100%; these figures were 56% (CI, 37-75%) and 94% (CI, 86-100%) for mpBAL. When both techniques were assessed together, sensitivity increased to 70% (CI, 53-87%). The use of a single catheter reduced the cost of the originally described pBAL procedure by approximately 50%. The use of a single catheter to perform a TPC followed by a mpBAL can improve the diagnostic yield in HIV-positive patients with bacterial pneumonia, and reduces its cost. 相似文献
130.
The re-administration of whole blood subjected to heat, ozonation and ultraviolet irradiation (VasoCare therapy) has been shown to elicit clinical benefits in individuals with vascular disease. Given that these stressors induce heat shock protein (Hsp) expression and that heat shock protein reactivity is implicated in the pathogenesis of vascular disease, this study assessed the effect of VasoCare on intracellular expression of Hsp60 and Hsp70 by treated peripheral blood leukocytes. Contrary to expectations, VasoCare induced a significant reduction (approximately 40%) in the proportion of peripheral blood mononuclear cells expressing intracellular Hsp60 and Hsp70, whereas it had no effect on heat shock protein expression by peripheral blood neutrophils. Cell surface heat shock protein expression was not detectable. The reduced expression of Hsp60 by mononuclear cells was concomitant with an increase in the levels of Hsp60 in treated plasma. Although the mechanism underlying the clinical effectiveness of VasoCare therapy has yet to be established, it may be that re-administration of treated blood or soluble factors derived therefrom modifies in vivo immune responsiveness to heat shock proteins or associated molecules. 相似文献