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Analysis of amino acids is complicated by treatment with ampicillin. High voltage electrophoresis, which is convenient for the qualitative assessment of metabolic diseases, yields smears of ampicillin that mask the bands of citrulline, homocitrulline, phenylalanine, cystine, and homocystine. The addition of penicillinase prior to high voltage electrophoresis eliminates ampicillin and other penicillins and reveals these key amino acids. 相似文献
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We compared the effects of an allergen challenge on airway responsiveness to methacholine, the slope of the dose-response curve (DRC) and post-methacholine fall in forced vital capacity (FVC) or forced expiratory volume in 1 s (FEV1)/FVC, and determined whether any changes in these parameters were related to the presence and magnitude of the late asthmatic response (LAR) in mild stable asthma. Twenty-three allergic asthmatic subjects had an allergen challenge, preceded and followed 24 (n = 12) and/or 48 (n = 22) h later by a methacholine challenge. Sixteen subjects had a dual asthmatic response to the allergen. On the post-allergen methacholine challenge, as compared with the pre-allergen test, differences in mean fall in FVC or FEV1/FVC at 20% fall in FEV1 and the slope of the DRC did not achieve statistical significance, even in the group with LAR, which showed a significant increase in airway responsiveness at 24 h. There was, however, a correlation between allergen-induced changes in PC20 and (1) the change in post-methacholine FVC fall in the LAR group at 48 h, and (2) the change in the slope of the DRC in the early-asthmatic-response group at 24 h. In conclusion, allergen-challenge-induced changes in airway response to methacholine are heterogeneous among asthmatic subjects and although it may increase airway responsiveness (PC20), particularly in late responders, it minimally affects the other aspects of airway response to methacholine, suggesting that a more powerful or sustained allergic stimulus is required to modify the latter. 相似文献
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Summary The thermal properties of an epoxy resin (diglycidyl ether Bisphenol A, DGEBA) cured with a primary amine (ethylenediamine, ETDA) and filled with 10, 20 and 30 wt. % of ultra fine copper particles were analyzed. The thermal results were evaluated by means of the Romero-Garcia method, which allowed to obtain the resin degradation kinetic parameters, as well as the possible decomposition mechanism. From the obtained results is possible to infer that higger copper content strongly affects the degradation process of the epoxy resin, which causes a drop off on the composites thermal stability. This behavior could be attributed to water presence, being this effect less pronounced for the resin with 10 wt. % copper and unfilled resin. Regarding to decomposition mechanism, three way transport showed the best correlation for all samples. 相似文献
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Endosurgical correction of the uterus was carried out in 57 patients. Indications for surgery were improper positions of the uterus-retroversio, retrodeviatio uteri, excessive mobility of the uterus, and complaints of heaviness at the bottom of the abdomen, leukorrhea, pain of different type in the lower portions of the abdomen, profuse and long menses, dyspareunic pain upon deep penetration, reduced libido, a sensation of a foreign body in the vaginal cleft, urine incontinence upon strain. The mean age of the patients was 35 +/- 3 years. The disease duration varied from 1 to 8-9 years. In 9 women endosurgical correction of the uterus was combined with other interventions on the pelvic organs: colpoperine-orrhaphy with levator plasty was carried out in 5, laparoscopic myomectomy in 2, and dissection of intraperitoneal adhesions in 2 patients. In addition, surgical sterilization was carried out in 54 patients. After surgery the patients were administered only nonnarcotic analgetics. All the patients were discharged on days 2-3, those subjected to combined treatment on days 8-9. The patients were followed up for up to 2 years. The general and psychoemotional status of the majority of patients improved, and the incidence of such symptoms as leukorrhea, pain at the bottom of the abdomen, profuse and long menses was 4, 6, and 5 times reduced, respectively. Endosurgical correction of the uterus in women of a reproductive age should be a method of choice; it can be carried out separately or in combination with plasty of the vaginal walls. 相似文献
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SA Nazarenko NV Ostroverkhova VP Puzyrev LP Nazarenko MN Filimonova OIu Koriagina 《Canadian Metallurgical Quarterly》1998,34(1):114-121
BACKGROUND: Many species of bats have two sets of submandibular glands, principal and accessory. The accessory gland may resemble the principal one but more often shows wide morphological divergence. The free-tailed bat, Tadarida thersites, is very unusual in that it has two sets of parotid glands rather than binary submandibular glands. We studied the ultrastructure of the principal parotid gland to establish a baseline for comparison with the accessory parotid. METHODS: Two specimens of adult free-tailed bats, one male and one female, were live-trapped in western Kenya. Parotid glands were fixed for electron microscopy using a protocol expressly designed for field fixation and then embedded by conventional means. RESULTS: Histologically, the principal parotid is a typical serous gland. The secretory granules of the endpiece cells have an unusual substructure in that they contain variable numbers of lucent halos and one or several spherules. Intercalated duct cells contain a significant number of dense, serous-like granules. Striated ducts have the usual basal configuration of mitochondria and folded plasma membranes, but the supranuclear cytoplasm contains many small, dense granules, so that these ducts resemble the granular convoluted tubules found in the submandibular glands of many families of rodents. The apices of the duct cells have a peculiar contour--the luminal surfaces obliquely invaginate into the apical cytoplasm, so that in thin section the luminal membranes appear to be underlaid by a layer of vacuoles. CONCLUSION: Although the principal parotid gland of the free-tailed bat shows some distinctive, species-specific ultrastructural features, it basically is similar to the parotid gland in two other molossid bats, Tadarida brasiliensis and Molossus molossus. The distinctive features in the principal parotid gland of T. thersites might relate to its feeding on hard-bodied insects and perhaps to the production of lysozyme. 相似文献