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41.
AIMS: To examine the relationships between body composition and changes in fasting glycaemia, and in indices of insulin secretion and insulin action over 6 years in females with a family history of Type 2 diabetes with or without prior gestational diabetes ('at risk' group, AR) and control females (control group, C). METHODS: At baseline and at follow-up, an oral glucose tolerance test and dual energy X-ray absorptiometry assessment of body composition were performed. Indices of insulin resistance (HOMA R') and insulin secretion (HOMA beta') were obtained from fasting insulin and glucose concentrations. RESULTS: At baseline, the groups were similar for age, body mass index, fasting levels of plasma glucose and insulin, HOMA R' and HOMA beta'. Despite similar total body fatness, AR had significantly greater waist circumference and central fat (both P < 0.02) compared with C. At follow-up there was a significant increase in central adiposity only in AR, and the fasting plasma glucose (FPG) level was higher in AR compared with C (5.0 +/- 0.2 vs. 4.3 +/- 0.2 mmol/l, P = 0.02). This rise in plasma glucose in AR was related to a decline in HOMA beta' (r = 0.45, P = 0.0065). Both the baseline and the increments in total and central abdominal fat mass were associated with the time-related decline in HOMA beta'. CONCLUSIONS: Six years after initial assessment, AR showed deterioration in FPG levels due predominantly to a decline in insulin secretion index without major change in insulin resistance index. Importantly, baseline body fatness (especially central adiposity), as well as increases in fatness with time, were the major predictors of the subsequent decline of insulin secretion index and the consequent rise in FPG.  相似文献   
42.
This paper presents the results of a survey of the structure of general practice in two contrasting areas within Greater Glasgow health board: the south west area had a more deprived social profile at the 1981 census and higher than average all cause and selected major cause standardized mortality ratios than the health board as a whole while the north west area had a more affluent social profile at the 1981 census and lower than average all cause and selected major cause standardized mortality ratios. The general practice survey data gathered in 1989 were supplemented with data from a survey of residents of the localities in three age cohorts carried out in 1987-88, which provided information on use of services, as well as perceived accessibility of and satisfaction with them. Despite the more deprived social and mortality profile of the south west area, and greater use of services, few systematic differences in the structure of general practices were found in the two areas. These findings support other studies which suggest that the stereotype of poorly resourced, low quality primary care in inner city areas may apply in London, but not elsewhere. Respondents in both areas were equally satisfied with services and found them accessible.  相似文献   
43.
The structure of cholinergic and adrenergic neuromuscular junctions in the sinus venosus of the toad, Bufo marinus, was determined by electron microscopy. From random sections of sinus venosus tissue it appeared that there were variable separations between cholinergic or adrenergic varicosities and the nearest sinus venosus muscle cell. However, when the structure of complete cholinergic and adrenergic varicosities was determined by examining serial electron micrographs, virtually all varicosities that lost their covering of Schwann cell were found to form an area of close apposition with an adjacent muscle cell. At the region of close apposition, the neuromuscular cleft was filled with a single layer of basal lamina to give a neuromuscular separation of about 70 nm. Synaptic vesicles within a varicosity were usually found to be concentrated towards the region of close apposition. These observations are discussed in relationship to the idea that when transmission occurs at these neuromuscular junctions the transmitters act on discrete pools of specialized subsynaptic receptors.  相似文献   
44.
OBJECTIVE: To determine the biochemical composition of amniotic fluid and extraembryonic coelomic fluid between 8 and 12 weeks gestation. DESIGN: Prospective observational study. SUBJECTS: 40 women with a normal pregnancy between 7 and 12 weeks gestation having termination of pregnancy. INTERVENTIONS: Before termination the women had a transvaginal ultrasound guided amniocentesis. Pure samples of amniotic fluid and extraembryonic coelomic fluid were obtained from each woman and standard biochemical variables were measured in each fluid sample immediately after collection. RESULTS: Levels of sodium, potassium and bicarbonate were significantly higher in amniotic fluid whilst chloride, urea, bilirubin, protein, albumin, glucose, creatinine, calcium and phosphate were present in higher concentrations in extraembryonic coelomic fluid. All differences in concentration were significant (P less than 0.05; unpaired t-test). No relation was demonstrated between electrolyte concentrations in amniotic fluid or coelomic fluid and stage of gestation. CONCLUSIONS: Amniotic fluid and extraembryonic coelomic fluid have a widely differing biochemical composition. The biological significance of these differences remains unexplained.  相似文献   
45.
There are an estimated 14 million individuals in the United States with diabetes mellitus. These individuals suffer a very high incidence of podiatric complications. This article focuses on the pharmacologic agents used in the management of hyperglycemia in the patient with diabetes mellitus, including insulin and sulfonylureas.  相似文献   
46.
C Bastien  K Campbell 《Sleep》1992,15(3):236-245
The functional significance and topographical variation of the different components of the evoked K-complex were examined. In the first experiment, the intensity of the stimulus (80 and 60 dB SPL) and its rise-and-fall time (2 and 20 milliseconds) were manipulated during nonrapid eye movement sleep. In the second experiment the tonal frequency (500, 1,000 and 2,000 Hz) of the stimulus was manipulated. In the first experiment, nine stimuli were presented every 10 seconds, whereas in the second, 20 consecutive stimuli were presented. The evoked K-complex consisted of two different negative components peaking at approximately 350 and 550 milliseconds, respectively, and followed by a positive component peaking at approximately 900 milliseconds. K-complexes were easier to elicit for high-intensity fast rise-and-fall time stimuli than for low-intensity slow rise-and-fall time stimuli. The probability of occurrence was not affected by the tonal frequency of the stimulus. When a K-complex was evoked, the amplitude and latency of N350, N550 and P900 remained invariant regardless of its intensity, rise-and-fall or its tonal frequency. The N550-P900 portion of the K-complex therefore appears to be an all-or-none phenomenon. On trials in which a K-complex could not be elicited, N350 was still visible although much attenuated. In these trials, its amplitude was further reduced when stimulus intensity was lowered. N350 might need to reach a certain critical threshold before the much larger N550-P900 complex is elicited.  相似文献   
47.
There is sometimes a discrepancy between the apparent thickness of postmenopausal endometria, as determined by transvaginal ultrasonography, and the examination of endometrial biopsies. We describe a case which showed that tamoxifen (20 mg/day over 12 months) decreased impedance to blood flow in the uterine arteries and increased the apparent thickness of the endometrium. Conversely, the analysis of biopsies suggested the presence of an atrophic endometrium. The introduction of sterile saline into the uterine cavity during a repeat ultrasound scan revealed the presence of a large, free-floating endometrial polyp, which was subsequently difficult to see by hysteroscopy.  相似文献   
48.
To determine the clinical features, course and outcome of patients with cardiac tamponade, 57 consecutive patients with new, large pericardial effusions were prospectively studied. Twenty-five patients (44%) developed cardiac tamponade with venous hypertension and a pulsus paradoxus greater than 10 mm Hg. Electrocardiography, radiographic studies and echocardiography did not differentiate patients with and without tamponade. All 57 patients underwent thorough diagnostic evaluation followed by subxiphoid pericardial biopsy and drainage. A diagnosis was obtained in 53 patients (93%). Collagen vascular disease was significantly more frequent in the 25 patients with than in the 32 without cardiac tamponade (24 vs 3%; p less than 0.05). The frequency of malignant and uremic effusions was equal in both groups, whereas radiation-induced effusions seldom produced tamponade. At 1-year follow-up, 3 patients (12%) with tamponade had recurrent effusions, and 1 needed reoperation. This was not significantly different from the 32 patients without tamponade. Twelve-month mortality was also similar in both groups (36 vs 44%). This prospective series disclosed several unexpected findings: (1) Cardiac tamponade occurred in almost 50% of patients with new large pericardial effusions; (2) both malignancy and collagen vascular disease occurred with equal frequency as etiologies, whereas radiation-induced tamponade was unusual; (3) thorough clinical evaluation resulted in few idiopathic etiologies; and (4) subxiphoid pericardiotomy was effective for both diagnosis and therapy of tamponade.  相似文献   
49.
Fungal infections and antifungal resistance are increasingly recognized. Antifungal susceptibility testing remains unstandardized, and a particularly important problem is endpoint determination. In this paper we propose the yeast metabolic reduction of the tetrazolium salt 2,3-bis(2- methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetraz olium hydroxide (XTT) as a colorimetric endpoint which is quantitative and objective. Amphotericin B, fluorocytosine, and fluconazole dose-response curves were obtained, and a metabolic MIC could be determined by using precise criteria.  相似文献   
50.
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