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81.
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   
82.
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   
83.
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   
84.
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   
85.
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   
86.
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   
87.
88.
The purpose of this clinical trial was to evaluate the reliability and time saved with a plasma arc curing unit (Apollo 95E, Dental/Medical Diagnostic Systems, Woodland Hills, Calif) compared with a conventional curing unit (Ortholux XL 3000, 3M Unitek, St Paul, Minn) for direct bracket bonding with resin adhesive. Forty-five patients were involved in the study, and 608 brackets were bonded in a contralateral quadrant pattern. The patients were followed for a mean (+/- standard deviation) period of 11 +/- 3.2 months. Survival analysis was carried out to compare the failure rate for the 2 techniques. The time required for bonding with each technique was also recorded. The mean survival time was 399 days, and there were no significant differences in survival time between the 2 bonding methods. Twelve bonding failures were reported with each technique. The curing time per bracket was significantly reduced with the plasma curing light compared with a conventional curing unit (65 +/- 19 vs 82 +/- 31 seconds). The plasma arc curing light can save chair-time without affecting the bonding failure rate.  相似文献   
89.
We studied a cohort of 496 patients who had multiple sclerosis (MS) for at least 10 years. Ten years after disease onset, 151 had benign MS defined as an Extended Disability Status Scale (EDSS) ≤3. Between benign and non-benign patients we compared gender, age at clinical onset, relapsing–remitting or primary progressive, symptoms at onset, recovery from first relapse, time between first and second relapse, number of relapses in the first 5 years, use of immunomodulatory drugs, and EDSS scores at 2, 5 and 10 years. A multivariate regression analysis showed that a relapsing–remitting course, a low EDSS score at 5 years, and a low number of relapses in the first 5 years were predictive for benign MS at 10 years. Other factors had no additional value. Thirty-five of the 51 patients (69%) with benign MS at 10 years were still benign at 20 years. A low 10-year EDSS score was the only clinical variable associated with a benign course at 20 years. Our results suggest that within the first 5 years from onset it is not possible to predict a benign course. Disease course, EDSS score and relapse rate at 5 years are predictors for benign MS at 10 years.  相似文献   
90.
Prevalence of isolated left ventricular (LV) diastolic dysfunction has been reported to be as high as one-third of all heart failure (HF) cases, with an increasing prevalence in the elderly population. However, there is a paucity of prospective data about the prevalence and prognosis of isolated LV diastolic dysfunction in an unselected population of patients hospitalized with HF. Therefore, we prospectively evaluated 179 consecutive patients discharged from our hospital with HF to assess the prevalence of systolic versus diastolic LV dysfunction among patients hospitalized with HF and to compare their demographics, clinical features, self-perceived quality of life (QOL), and 6-month readmission rate and mortality. Among them, 133 (59% men, median age 74 years) showed in sinus rhythm and had no significant primary valvular disease. LV diastolic dysfunction was diagnosed on the basis of the European Study Group on Diastolic HF echocardiographic criteria. QOL was assessed at hospital discharge and 6-month follow-up visit using the Minnesota Living with HF questionnaire. Survival of patients with HF was compared with that of age- and sex-matched general population. In all, 29 patients (22%) had isolated LV diastolic dysfunction and 102 (78%) had prevalent LV systolic dysfunction (ie, LV ejection fraction 相似文献   
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