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991.
A S Masibay P K Qasba 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(15):5733-5737
A bovine beta-1,4-galactosyltransferase (GT; EC 2.4.1.90) cDNA in an Okayama-Berg vector, pLsGT, was constructed from a partial cDNA clone and a genomic fragment. We report that the cDNA sequence of pLsGT, in a transient expression assay in COS-7 cells, codes for an enzymatically active GT protein. There is an approximately 12-fold increase in the GT activity in pLsGT-transfected cells compared to cells transfected with the antisense bovine GT construct, pLasGT, or pSV2Neo or mock-transfected cells. The increased activity is correlated with the increase in bovine GT mRNA, which is distinguishable from COS GT mRNA with a 3'-end-specific probe of pLsGT. The expressed GT activity is modulated by alpha-lactalbumin, which changes the acceptor specificity to glucose to synthesize lactose. Polyclonal antibody raised against SDS/PAGE-purified bovine milk GT and a monoclonal antibody (mAb 4-10) directed against a synthetic peptide corresponding to the amino-terminal region of the protein encoded by pLsGT bind the expressed protein, and the resulting immunoprecipitates exhibit GT enzymatic activity. 相似文献
992.
993.
994.
C4 concentrations and C4 deficiency alleles in systemic lupus erythematosus. 总被引:1,自引:0,他引:1
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In a study of 66 patients with systemic lupus erythematosus (SLE) and 80 controls it was found that the presence of two deficiency (null) alleles of C4 had a significant effect on mean C4 concentrations in serum. In six controls who each had two C4 null alleles the mean C4 concentration in serum was 56% lower than in 43 controls without C4 null alleles; the nadir of the C4 concentration in four patients with SLE with two null alleles was also lower by a mean of 55% than in 32 patients who did not have null alleles. Reduced production of C4 allotypes in subjects with two null alleles may be an important determinant of total C4 concentration in patients with SLE. For optimal interpretation of C4 concentrations in SLE, C4 allotyping appears to be indicated, particularly to identify patients who have two null alleles of C4. 相似文献
995.
Intestinal infarction caused by carcinoid associated elastic vascular sclerosis: early presentation of a small ileal carcinoid tumour. 总被引:2,自引:1,他引:1
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We describe a patient with extensive ischaemic necrosis of the ileum as a result of elastic vascular sclerosis (EVS). A 2 cm carcinoid tumour was located nearby with microscopic evidence of spread to regional lymph nodes. Severe intestinal ischaemia caused by carcinoid associated EVS may be the presenting feature of small carcinoid tumours resulting in their early diagnosis. 相似文献
996.
The activation of phospholipase A2 is believed to have an important role in the inflammatory process owing to its induction of eicosanoids, platelet activating factor, and other mediators. Soluble phospholipase A2 has been associated with exudates in different inflammatory conditions. In this review the general physiology and control of this enzyme and, in particular, the most recent findings on human synovial fluid phospholipase A2s are discussed. 相似文献
997.
术后胆漏和继发胆管狭窄的内镜治疗 总被引:1,自引:1,他引:0
胆漏和继发胆管狭窄是严重的外科并发症,传统的治疗方法是再次开腹手术,但再手术并发症多,死亡率高。而内镜胆管造影不仅可明确诊断,且内镜下治疗具有安全、疗效肯定、创伤小和并发症少等优点,可作为大多数胆漏和胆管狭窄患者首选治疗方法。 相似文献
998.
本文着重介绍了BIPAP无创呼吸机操作原理及基本使用原则.为了防止概念混淆,特别对英文缩写同为BIPAP的双相气道正压通气作了简要的对比说明. 相似文献
999.
1000.