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排序方式: 共有6846条查询结果,搜索用时 31 毫秒
41.
BA Rybicki MJ Maliarik M Major J Popovich MC Iannuzzi 《Canadian Metallurgical Quarterly》1997,18(4):707-717
Hereditary susceptibility to sarcoidosis is suggested by ethnic preponderance, familial clustering, and multigenerational involvement. The genetics of sarcoidosis cannot be adequately addressed in small samples of patients; a large-scale study with stratification for patient phenotypic differences is necessary. A study that uses both genetic marker and environmental data would be able to control for and examine different causative mechanisms. Until such a well-designed, comprehensive study is carried out, we are left with interesting patterns of disease in families and uncertain allelic associations. 相似文献
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Standards which eliminate ambiguity in reporting nonlinear phenomena, especially in the increasingly complex realm of biaxial crystals, are proposed. In order to restore uniformity to the designation of crystallographic axes and crystal tensor properties, adoption of IEEE/ANSI Std. 176, with a small but much needed modification for crystal class mm2, is recommended. For the reporting of nonlinear interaction characteristics, other frames are proposed which result in simpler rules than heretofore given for categorizing phase-matching loci, and for characterizing eigenmode polarizations, double refraction, effective nonlinear coupling, and first- and second-order acceptance bandwidths (angular, spectral, thermal) along these loci. Similarities as well as differences between biaxial and uniaxial crystals are emphasized 相似文献
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Lewinsohn Peter M.; Roberts Robert E.; Seeley John R.; Rohde Paul; Gotlib Ian H.; Hops Hyman 《Canadian Metallurgical Quarterly》1994,103(2):302
In a prospective study of adolescent depression, adolescents (N?=?1,508) were assessed at Time 1 and after 1 yr (Time 2) on psychosocial variables hypothesized to be associated with depression. Most psychosocial variables were associated with current (n?=?45) depression. Formerly depressed adolescents (n?=?217) continued to differ from never depressed controls on many of the psychosocial variables. Many of the depression-related measures also acted as risk factors for future depression (n?=?112), especially past depression, current other mental disorders, past suicide attempt, internalizing behavior problems, and physical symptoms. Young women were more likely to be, to become, and to have been depressed. Controlling for the psychosocial variables eliminated the gender difference for current and future but not for past depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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EM de Jong BA Seegers MK Gulinck JB Boezeman PC van de Kerkhof 《Canadian Metallurgical Quarterly》1996,193(4):300-303
We present the first case of esophagogastric devascularization and esophagogastric transection using a stapler through laparoscopic surgery. The procedure was performed in a 71-year-old diabetic woman with alcoholic liver cirrhosis (Child-Pugh B class), portal hypertension, bleeding grade III esophageal varices, and a previous bleeding episode. The surgical technique was carried out without problems, and the patient had an excellent postoperative condition. Esophagogastric devascularization with esophageal transection using a stapler through laparoscopic surgery is a feasible technique that accomplishes the same and all objectives of the open procedure. Operative time in both methods is the same, whereas surgical trauma, inmunologic depletion, amount of transfused blood, pain, use of analgesics, and hospital stay are reduced in the laparoscopic technique. 相似文献
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SW Qian JK Burmester PD Sun A Huang DJ Ohlsen L Suardet KC Flanders D Davies AB Roberts MB Sporn 《Canadian Metallurgical Quarterly》1994,33(40):12298-12304
Transforming growth factor-beta (TGF-beta) is a potent regulator of cell growth and differentiation. On the basis of the crystal structure of TGF-beta 2, we have designed and synthesized two mutant TGF-beta s, TGF-beta 1 (71 Trp) and TGF-beta 1 (delta 69-73). Although both of these molecules inhibited the growth of Mv1Lu mink lung epithelial cells and LS1034 colorectal cancer cells, which are affected equally by TGF-beta 1 and TGF-beta 2, TGF-beta 1 (delta 69-73) was much less potent than TGF-beta 1 or TGF-beta 1 (71 Trp) at inhibiting the growth of LS513 colorectal cancer cells which are growth-inhibited by TGF-beta 1 but not TGF-beta 2. Both TGF-beta 1 (71 Trp) and TGF-beta 1 (delta 69-73) increased levels of mRNAs for fibronectin and plasminogen activator inhibitor with Mv1Lu cells, whereas only TGF-beta 1 (71 Trp) and not TGF-beta 1 (delta 69-73) up-regulated the mRNA level of carcinoembryonic antigen in LS513 cells. The expression level of carcinoembryonic antigen mRNA in LS1034 cells was not altered by either wild-type or mutant TGF-beta s. Receptor labeling experiments demonstrated that TGF-beta 1 (71 Trp) bound with high affinity to the cell-surface receptors of Mv1Lu, LS1034, and LS513 cells while TGF-beta 1 (delta 69-73) bound effectively to the receptors of Mv1Lu and LS1034 cells but much less to the receptors on LS513 cells.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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PURPOSE: The phenoxyacetic acid, ethacrynic acid (ECA), has potential use in glaucoma therapy because it acts to increase aqueous outflow in vivo and in vitro. In human trabecular meshwork (HTM) cell culture, ECA acts to change cell shape and attachment, effects that have been correlated with microtubule (MT) alterations and chemical sulfhydryl (SH) reactivity. To further explore these actions, we evaluated two non-SH reactive phenoxyacetic acids, inadcrinone and ticrynafen, and the MT-disrupting drug vinblastine. METHODS: Excised bovine and porcine eyes were perfused and outflow facility measured. Calf pulmonary artery endothelial and HTM cells were grown in culture and cytoskeletal effects evaluated after drug treatment. RESULTS: Indacrinone, ticrynafen, and vinblastine all caused an increase in outflow facility. In contrast with ECA, the outflow effects of indacrinone and ticrynafen were not blocked by excess cysteine. Although indacrinone and ticrynafen produced changes in cell shape in vitro, the beta-tubulin staining pattern of treated cells was not altered. Vinblastine caused cell shape change and the expected MT disruption. CONCLUSIONS: Phenoxyacetic acids can increase aqueous outflow facility and alter HTM cell shape and attachment in vitro by a non-SH, non-MT mechanism (which is probably shared also by ECA). These findings suggest the possibility of a broader class of glaucoma drugs that may be directed at the HTM. An understanding of the cellular target for these drugs has implications both for potential glaucoma therapy and for the cytoskeletal mechanisms involved in normal outflow function. 相似文献