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51.
52.
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   
53.
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   
54.
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   
55.
56.
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   
57.
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   
58.
After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation.  相似文献   
59.
Left ventricular geometry is distorted after anterior infarction caused by occlusion of a wrap around left anterior descending artery. Loss of the apex creates a spherical left ventricular (LV) chamber, whose rebuilding requires reconstruction techniques that exclude the non-functional inferior wall. The described technique of tailoring the apex defines a way to create an oblique elliptical rim for subsequent patch placement to complete the restoration procedure. This method of ventricular rebuilding differs from methods that follow the inferior wall scar, which result in a restoration procedure that leaves a spherical or box-like apical region.  相似文献   
60.
OBJECTIVE: To determine the incidence of deep venous thrombosis (DVT) recurrence in young people, and its association with some genetic polymorphisms (FV G1691A, FII G20210A, MTHFR C677T, PAI-1 4G/5G). DESIGN: Prospective cohort study. METHODS: A database was established prospectively to follow-up a cohort of unselected patients who had had a first episode of objectively proven DVT under the age of 40 years. All patients had DNA analysis for heritable thrombophilia. We excluded patients with deficiency of antithrombin, protein C or protein S, malignant disease, antiphospholipid syndrome, or a requirement for long-term antithrombotic treatment. The end-point was objective evidence of symptomatic DVT recurrence. RESULTS: Eighty-seven patients were enrolled in the study. Mean duration of follow-up was 4.07 years. At 2 years, the cumulative recurrence rate was 19.3%. The risk of risk was not related to presence or absence of laboratory evidence of genetic polymorphisms: FV G1619A (HR 1.26 [95%CI: 0.64-2.46]; p = 0.51), FII G20210A (HR 0.81 [95%CI: 0.35-1.89]; p = 0.62), MTHFR C677T (HR 1.26 [95%CI: 0.56-2.81]; p = 0.58), PAI-1 4G/5G (0.84 [95%CI: 0.35-2.05]; p = 0.71). CONCLUSION: In this study, the risk of recurrent deep venous thrombosis in young people was not related with the presence of FV G1691A, FII G20210A, MTHFR C677T or PAI-1 4G/5G polymorphisms.  相似文献   
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