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101.
102.
The history of prealbumin dates back to the early forties and may be divided into three parts, based on a chronological and functional approach. The first part--the discovery and the identification of prealbumin--was essentially based on classical protein chemistry methods. The second--the demonstration of prealbumin as a thyroid hormone-binding protein (thyroxine-binding prealbumin)--has greatly benefited from isotopic techniques. The third one--establishing prealbumin as a nutritional marker--was a result of field studies on nutrition. The discovery of the role of prealbumin in retinol binding led to a change in its name, prealbumin becoming transthyretin. Finally, structural studies and mutation analysis of transthyretin in patients with amyloid neuropathy have opened a new area of research.  相似文献   
103.
本文报告29对轻度贫血和非贫血儿童在平板机运动试验条件下的最大运动耐受时间,耗氧量、心率和运动后血乳酸浓度。结果表明,轻度贫血组儿童最大耐受时间、最大耗氧量均低于非贫血组。运动后血乳酸高于非贫血组。经一个月补铁治疗后,贫血组最大耐受时间提高0.9分钟,血乳酸降至非贫血组水平,但最大耗氧量无显著性变化。由此说明轻度贫血对学龄儿童体力工作能力有一定的影响。  相似文献   
104.
The effects of 2,4-Dichlorophenoxyacetic acid on the growth rate, chemical composition, 14C-2,4-dichlorophenoxyacetic acid and 45Ca2+ uptake by Rhizobium sp. M 4 able to nodulate Arachis hypogaea were determined. Cellular growth was diminished by the presence of 10?3 M 2,4-dichlorophenoxyacetic acid in the medium. Alterations in cellular chemical composition, in 14C-2,4-dichlorophenoxyacetic acid and in 45Ca2+ uptake were found.  相似文献   
105.
5-Fluorouracil, 5-fluorouridine (FUrd), 5-fluoro-2'-deoxyuridine (FdUrd), 5-fluorocytidine (FCyd), 5-fluoro-2'-deoxycytidine (FdCyd), 5-trifluoro-2'-deoxythymidine (F3dThd), and the 5'-monophosphates and 3',5'-cyclic monophosphates thereof were found to inhibit thymidine kinase-deficient (TK-) mutant strains of herpes simplex virus (HSV) at a much lower concentration than the wild-type (TK+) HSV strains. Other 5-substituted 2'-deoxyuridines that have previously been recognized as potent thymidylate synthase inhibitors behaved in a similar fashion. The activity of FdUrd, FdCyd, F3dThd, and their 3',5'-cyclic monophosphates against TK-HSV was readily reversed by 2'-deoxythymidine (dThd) but not by 2'-deoxyuridine (dUrd). These compounds also inhibited the incorporation of [6-3H]dUrd into DNA at a concentration which was up to 5 orders of magnitude lower than the concentration at which the incorporation of [methyl-3H] dThd was inhibited. Thus, while not being a target for the well established anti-HSV compounds in TK+HSV-infected cells, thymidylate synthase appears to be an important target in TK-HSV-infected cells. In addition to dTMP synthase, TK-HSV-infected cells appear to reveal other therapeutically exploitable targets such as OMP decarboxylase (towards pyrazofurin), CTP synthase (towards carbodine and its cyclopentenyl analogue), dihydrofolate reductase (towards methotrexate), and S-adenosylhomocysteine hydrolase (towards neplanocins).  相似文献   
106.
107.
Insulin and the insulin-like growth factors IGF-I and IGF-II are thought to exert their mitogenic effects in cultured chick embryo fibroblasts and human skin fibroblasts via IGF receptors rather than via insulin receptors. These effects appear to be mediated by the type I subtype of IGF receptor, which is structurally similar to the insulin receptor and exhibits significant cross-reactivity with insulin. As a first step in our long-range goal of defining those features of the IGF-I and IGF-II molecules that confer enhanced mitogenic activity and reactivity with these mitogenic type I IGF receptors, we have prepared two hybrid insulin-IGF molecules and examined their mitogenic and binding activities: (1) A27-insulin, containing an elongated 27-residue A-chain (in which the 6-residue D-domain of IGF-II was added to the carboxy-terminus of the 21-residue A-chain of insulin) combined with the B-chain of insulin; and (2) A insulin-B IGF-1, containing the A-chain of insulin and the synthetic 30-residue B-domain of IGF-I. Both hybrid molecules stimulated DNA synthesis and inhibited 125I-IGF-I binding to type I IGF receptors in both chick embryo and human fibroblast cultures. A27-insulin had considerably greater mitogenic potency and binding potency than A insulin-B IGF-I. Neither hybrid molecule was more potent in these assays than insulin, indicating that the presence of D IGF-II or B IGF-I by itself was not sufficient to increase the mitogenic potency of insulin in fibroblasts. By contrast, A insulin-B IGF-I showed enhanced reactivity with an antiserum to IGF-I. A27-insulin retained significant insulin-like metabolic activity despite the presence of the D-domain of IGF-II.  相似文献   
108.
Eighty-two consecutive aphakic or pseudophakic retinal detachments were treated by buckling and vitrectomy procedures. Functional results (86.6%) and the incidence of proliferative vitreoretinopathy (11%) were comparable with reports of cases treated by the classic method.Presented at the 1984 meeting of the Club Jules Gonin in Lausanne, Switzerland  相似文献   
109.
The use of therapeutic apheresis in very low weight patients is generally thought to have limitations, because of possible severe adverse reactions, potential risk related to the extracorporeal procedure, due to the low weight of the young patients. A careful therapeutic approach using appropriate precautions, and also introducing modifications to the standard procedure, can minimise the risk without compromising the efficacy of the plasmapheresis. The aim of the study was to evaluate apheresis tolerance and acceptability in children [Artif. Organs. 21 (1997) 1126] and infants [J. Clin. Apheresis 5 (1989) 21] with inherited lipid metabolism disorder, familial hypercholesterolemia (FH), primary hyperlipoproteinemia (lipoprotein phenotype I), and acute leukemia, weighing on average 20.55 kg. One thousand one hundred twenty three aphereses were completed. Three types of apheresis were performed: leukapheresis, plasma exchange, dextran sulphate cellulose (DSC) low density lipoprotein (LDL)-apheresis. Three different types of continuous flow systems were used. Technical adaptation depending on patients blood volume, body mass index, hematocrit, type of system used, permitted us to perform complete aphereses, obtaining a high degree of tolerance and acceptability of the treatment. The use of plasmapheresis is regarded to be an extreme therapeutic measure in children. However, when the need for such treatment is undebatable, plasmapheresis must be done. A well-trained and experienced team can overcome the technical difficulties in order to complete the procedures without complications. The most frequently observed adverse effects are vascular relative access insufficiency (2.0%), and mild hypotension (2.0%).  相似文献   
110.
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