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排序方式: 共有3279条查询结果,搜索用时 15 毫秒
1.
Lesley A. Inker Morgan E. Grams Andrew S. Levey Josef Coresh Massimo Cirillo John F. Collins Ron T. Gansevoort Orlando M. Gutierrez Takayuki Hamano Gunnar H. Heine Shizukiyo Ishikawa Sun Ha Jee Florian Kronenberg Martin J. Landray Katsuyuki Miura Girish N. Nadkarni Carmen A. Peralta Dietrich Rothenbacher Mark Woodward 《American journal of kidney diseases》2019,73(2):206-217
2.
G B Hopkinson D A Woodward N Prasad B R Bullen 《Annals of the Royal College of Surgeons of England》1983,65(5):323-324
The presence of accessory channels between the liver and extrahepatic bile ducts has long been recognised by anatomists and the division of such ducts may be a cause of bile leakage following cholecystectomy. However, visualisation of accessory bile ducts at operation is difficult as they are often small and sometimes less than 1 mm in diameter. Cholangiography has been used to help in the identification of accessory ducts in 50 patients included in a prospective trial. X-rays were taken after dissection of the gall bladder from its bed and extravasation of contrast was seen on five occasions (10%) suggesting leakage from divided accessory ducts. The identification of damage to accessory bile ducts in 10% of patients suggests that this may occur more frequently than previously supposed. 相似文献
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Abstract: Native chemical ligation has proven to be a powerful method for the synthesis of small proteins and the semisynthesis of larger ones. The essential synthetic intermediates, which are C‐terminal peptide thioesters, cannot survive the repetitive piperidine deprotection steps of Nα‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry. Therefore, peptide scientists who prefer to not use Nα‐t‐butyloxycarbonyl (Boc) chemistry need to adopt more esoteric strategies and tactics in order to integrate ligation approaches with Fmoc chemistry. In the present work, side‐chain and backbone anchoring strategies have been used to prepare the required suitably (partially) protected and/or activated peptide intermediates spanning the length of bovine pancreatic trypsin inhibitor (BPTI). Three separate strategies for managing the critical N‐terminal cysteine residue have been developed: (i) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐(N‐methyl‐N‐phenylcarbamoyl)sulfenylcysteine [Fmoc‐Cys(Snm)‐OH], allowing creation of an otherwise fully protected resin‐bound intermediate with N‐terminal free Cys; (ii) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐triphenylmethylcysteine [Fmoc‐Cys(Trt)‐OH], generating a stable Fmoc‐Cys(H)‐peptide upon acidolytic cleavage; and (iii) incorporation of Nα‐t‐butyloxycarbonyl‐S‐fluorenylmethylcysteine [Boc‐Cys(Fm)‐OH], generating a stable H‐Cys(Fm)‐peptide upon cleavage. In separate stages of these strategies, thioesters are established at the C‐termini by selective deprotection and coupling steps carried out while peptides remain bound to the supports. Pilot native chemical ligations were pursued directly on‐resin, as well as in solution after cleavage/purification. 相似文献
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Wasting protein-energy malnutrition (PEM) was induced in male C57BL/6J mice fed a low-protein diet ad libitum from 23 to 37 d of age. In comparison with a complete diet, the low-protein formulation reduced delayed hypersensitivity to sheep red blood cells (SRBCs) assessed on day 14 of feeding by measuring increased footpad thickness (mean +/- SD: 4 +/- 4% vs 22 +/- 8%, P less than 0.01), after immunization on day 9, and after challenge with SRBCs on day 13. By contrast, the low-protein diet did not affect the anti-SRBC hemagglutinin titer (8.3 +/- 2.2 vs 9.1 +/- 1.1, P greater than 0.30) despite profound reduction in numbers of splenic plasma cells secreting IgM-class anti-SRBCs (7.3 +/- 3.1 vs 49.9 +/- 23.8 x 10(-3), P less than 0.001), after immunization on day 9 and assessment on day 14. Thus, direct experimental evidence, previously altogether lacking, is provided in support of the concept, central to nutritional immunology, that acquired cell-mediated immunity is less resistant than is systemic humoral immunity to the depressive influence of pre-adolescent, wasting PEM. 相似文献
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Juri V. Kaude M.D. James D. McDowall Charles L. Neustein Edward R. Woodward Patricia G. Wright 《Abdominal imaging》1981,6(1):135-140
Eighty patients who had undergone jejunoileal bypass for morbid obesity were examined by ultrasound at their routine follow-up visits to the clinic. Ultrasonographic evidence of intestinal intussusception was found in 15 patients (19%). Two of these patients were asymptomatic. Ultrasonographic findings were confirmed by operation in 6 patients (5 with intussusception, 1 negative). 相似文献
10.
Adopting an information management approach to the design and implementation of information systems.
As the NHS adopts an information management approach to coordinated handling of total information resources, methods of systems analysis and design require assessment to ensure that they are appropriate. Mandatory use of Structured Systems Analysis and Design Methodology (SSADM) may be encouraging a damagingly narrow view of information systems. Research is described in which an holistic view of information systems is applied, allowing the needs of information users to play a stronger role in determining how information will be supplied to them. The techniques may also assist the training activities associated with implementing new systems. 相似文献