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81.
Use of peer ratings in a pediatric residency 总被引:1,自引:0,他引:1
82.
Retinal pigment epithelial change and partial lipodystrophy 总被引:1,自引:0,他引:1
T M Davis D R Holdright W E Schulenberg R C Turner G F Joplin 《Postgraduate medical journal》1988,64(757):871-874
Cuticular drusen and retinal pigment epithelial changes were found incidentally in a 27 year old Lebanese woman during assessment of partial lipodystrophy. Her vision was normal despite involvement of both maculae. The patient had hypocomplementaemia, but serum C3 nephritic factor was absent and renal function was normal. She had impaired glucose tolerance and a continuous infusion of glucose with model assessment (CIGMA) test revealed low normal tissue insulin sensitivity and high normal pancreatic beta cell function. Mild fasting hypertriglyceridaemia (2.0 mmol/l) may have been secondary to impaired insulin sensitivity. Endocrine function was otherwise normal apart from a completely absent growth hormone response to adequate hypoglycaemia. The simultaneous occurrence of partial lipodystrophy and retinal pigmentary epithelial and basement membrane changes appears to be a newly recognized syndrome. 相似文献
83.
84.
Despite advances in the neuro-imaging of the brain stem, an accurate diagnosis of intrinsic lesions in this region requires tissue sampling and histological verification. We have performed a series of computer-directed stereotactic procedures in 12 patients with intrinsic brain stem lesions. A positive diagnosis was obtained in 11 cases and therapeutic intervention was possible in four. There was no operative mortality. Because of the importance of an accurate diagnosis in order to avoid inappropriate therapy, together with the relative safety of the technique, computer-directed stereotactic biopsy should be considered in all patients harbouring an intrinsic brain stem mass. 相似文献
85.
A R Davis 《The Journal of nursing education》1988,27(4):156-160
New research in the areas of cognition, learning, memory, and motivation indicates that people can learn more and at a faster rate, than was previously thought, by means of improved teaching strategies aimed specifically at enhancing memory storage and retrieval, cognition, and learning (Estes, 1983; Kirby & Biggs, 1980; Murphy & Smith, 1982). Other research in psychology, educational psychology, biochemistry, and neurology shows that human intelligence can be more fully developed or modified (Machado, 1980). One of the means to achieve these ends is teaching strategies developed specifically to enhance the brain's natural capacities. 相似文献
86.
M Davidson L Bastiaens B M Davis M B Shah K L Davis 《Endocrinology & Metabolism Clinics of North America》1988,17(1):149-157
In conclusion, at present, no consistent endocrine abnormalities can be detected in patients suffering from Alzheimer's disease. However, assessment of neuroendocrine function might help identify subpopulations of patients with particular neurotransmission abnormalities who are likely to benefit from a specific pharmacologic strategy. For example, patients in whom cholinomimetic drugs produce the greatest elevation in plasma cortisol concentration appear to derive the most symptomatic benefit from these drugs. 相似文献
87.
OBJECTIVE--To develop a noninvasive clinical predictive model for acute congestive heart failure (CHF) in a frail elderly cohort using bedside clinical assessment (medical history and physical examination) and venous atrial natriuretic peptide (ANP) levels. DESIGN--One-year prospective blinded cohort study. SETTING--Life care facility. PARTICIPANTS--Three hundred thirty-one frail, elderly volunteers free of acute illness at study entry (mean +/- SD age, 88 +/- 7 years; 23% male, 77% female). MAIN OUTCOME MEASURE--Clinical episodes of CHF with confirmation of acute pulmonary edema by chest roentgenogram. RESULTS--Fifteen percent of the elderly cohort developed at least one episode of CHF during the 1-year follow-up period. Those developing CHF had significantly higher mean +/- SE ANP values at study entry: 493 +/- 55 vs 207 +/- 15 pmol/L. The risk for development of CHF rose progressively with increasing ANP levels at study entry. In multivariate analysis, only two independent variables significantly predicted CHF: ANP value greater than 200 pmol/L (adjusted odds ratio [OR], 7.9; 95% confidence interval [CI], 3.2 to 19.2) and history of CHF in the previous year (adjusted OR, 7.0; 95% CI, 2.9 to 17). Stratifying the cohort by these two variables results in three CHF risk groups: 55% of the population at 3% annual risk of CHF, 37% of the population at 20% to 24% annual risk of CHF, and 8% of the population at 66% annual risk of CHF. CONCLUSIONS--This simple clinical prediction model identifies elderly subjects at risk for CHF and allows appropriate focusing of medical resources for prevention, early detection, and treatment of this highly morbid clinical syndrome. 相似文献
88.
Eight male habitual smokers smoked two cigarettes over a 20-min period following a 12-h period of abstinence. Antecubital venipuncture was performed immediately before, immediately after, and 55 min and 2 h after smoking had ceased. At these times, the mean values (+/- SD) of collagen-induced platelet aggregation were 45 +/- 5, 68 +/- 5, 59 +/- 6 and 52 +/- 5 chart units, respectively, while the corresponding values for the mean platelet aggregate ratio were 0.91 +/- 0.01, 0.82 +/- 0.03, 0.87 +/- 0.02 and 0.90 +/- 0.02, respectively. Mean collagen-induced platelet aggregation was significantly (P less than 0.005) higher immediately after, and 55 min and 2 h after smoking. The mean platelet aggregate ratio was significantly (P less than 0.001) lower immediately after and 55 min after smoking. Correlation coefficients between the concentration of nicotine in each of the 24 plasma samples obtained after smoking and the corresponding values of collagen-induced platelet aggregation and the platelet aggregate ratio were 0.41 (P less than 0.05) and -0.50 (P less than 0.02), respectively. It is concluded that when habitual smokers abstain from smoking overnight, a 20-min period of cigarette smoking may enhance platelet aggregability for as long as 2 h. 相似文献
89.
Areas of signal loss in brain overlying air-containing structures at the skull base are commonly observed on axial fast MR images. The nature of this effect, which can mimic the appearance of cerebral hemorrhage, is investigated in a phantom study and in a normal volunteer. The magnitude of the signal loss is found to be inversely related to the distance of the scanning plane from the air-containing structure and directly related to the echo time. 相似文献
90.