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941.
Summary The natural evolution of neural dysfunction was studied prospectively over 5 years following diagnosis of Type 1 (insulin-dependent) diabetes in 32 patients aged 12–36 years. Motor and sensory nerve conduction velocities, heart rate variation at rest and during deep breathing, and pupillary function were measured at diagnosis and after 3,12, 24,48, and 60 months. Thermal and vibration sensation thresholds were determined after 24, 48, and 60 months of diabetes. Mean HbA1 levels of months 3–60 within the normal range of <8.3% (7.3±0.2%) were observed in 13 patients (Group 1), while a mean HbA1 of months 3–608.3% (10.0±0.3%) was found in 19 patients (Group 2). Mean nerve conduction was significantly diminished in Group 2 as compared with Group 1 in at least 4 out of 6 nerves tested during months 12–60 (p<0.05). Both tests of heart rate variation were significantly impaired in Group 2 as compared with Group 1 after 24 and 60 months (p<0.05), but no differences in pupillary function were observed between the groups. Thermal discrimination but not vibration perception thresholds on the foot were significantly higher in Group 2 than in Group 1 at 40 and 60 months (p<0.05). Abnormalities in nerve conduction, thermal discrimination, and heart rate variation, but not vibration perception threshold and the pupillary function tests were significantly more frequent in Group 2 than in Group 1 at 60 months (p<0.05). After 60 months, none of the patients of Group 1, but 6 and 4 patients of Group 2 developed subclinical or symptomatic neuropathy, respectively (p<0.05). These findings suggest that the evolution of subclinical and symptomatic neuropathy during the first 5 years after diagnosis of Type 1 diabetes may be predicted by poor glycaemic control and prevented by near-normoglycaemia.  相似文献   
942.
Seventy-eight patients with cirrhosis were prospectively followed for up to 20 months, on the average. At entry into the study, galactose elimination capacity, aminopyrine breath test, and ICG clearance were measured. At the end of the study, 27 patients had died. Univariate analysis using the Kaplan-Meier method showed that both quantitative liver function tests (galactose elimination capacity:P<0.025; aminopyrine breath test:P<0.001; ICG clearance:P<0.005) and common clinical and biochemical data (encephalopathy:P<0.001; ascites:P<0.001; serum bilirubin:P<0.005; serum albumin:P<0.001; prothrombin index:P<0.05) were significant predictors of survival. To investigate whether quantitative liver function tests could contribute to a better definition of the prognosis, once Pugh score had already been taken into account, a multiple regression analysis according to the Cox model was performed. Pugh score and galactose elimination capacity resulted in the only independent prognostic covariates. From them a prognostic index was calculated, and the model was validated in an additional sample of 70 patients investigated according to the same protocol. The contribution GEC gave to the assessment of overall prognosis over that obtained using the Pugh score was slight, as estimated by the statistical parameters of the Cox's model, but was significant as assessed by a ROC curve analysis (P=0.05). These data show that all quantitative liver function tests were predictors of survival in cirrhosis, and that the galactose elimination capacity added some new prognostic information to those already available using the Child-Turcotte-Pugh classification.This study was supported in part by a grant from the Italian Ministry of Education (National Project Liver Cirrhosis). Part of this study was presented at the 22nd Meeting of the European Society for Clinical Investigation, Graz, Austria, April 20–23, 1988.  相似文献   
943.
Radionuclide left ventricular (LV) peak filling rate (PFR) wasdetermined in 185 survivors of acute myocardial infarction (AMI)and expressed in units of (1) end-diastolic volume per second( EDV s–1), (2) stroke volume per second (SV s–1),or (3) actual millilitres of blood filled into the left ventricleper second (ml s–1). The purpose of the study was to assessthe interrelationship between the three expressions of PFR,and to analyse their significance with regard to signs of congestiveheart failure and 1-year survival in patients with AMI. PFREDVs–1, PFRSVs–1 and PFR mis–1 had a poorrelationship to each other, were all influenced by L V volumesand ejection fraction, and supplied contradictory informationwith regard to LV filling in patients with heart failure. Noneof the three expressions of LV peak filling rate had an associationto heart failure that was independent of LV volume and ejectionfraction. A low PFR EDVs–1 in contrast to a high PFR SVs–1 was associated with a high 1-year cardiac mortality,suggesting that these ‘normalized’ indices of LVpeak filling rate signalled LV size and stroke volume ratherthan actual LV filling behaviour. No association was presentbetween PFR mis–1 and 1-year mortality. We conclude thatthe clinical use of radionuclide LV PFR in patients with AMImay lead to spurious results, unless the influence of LV sizeand ejection fraction is taken into consideration.  相似文献   
944.
Summary Renal function and psychomotor performance (eye-hand coordination, arm-hand steadiness) of a group of 43 workers exposed to mercury vapor were examined. Their mean age and average duration of exposure to mercury were 38 and 5 years, respectively. The results were compared with those obtained in a matched group of 47 control workers. Increased proteinuria and albuminuria were found slightly more prevalent in the Hg-exposed group than in the control workers. These results are in agreement with those found during a previous study carried out in another group of workers also exposed to elemental mercury (Bucket et al. 1980). The scores of the psychomotor tests were less satisfactory in the Hg workers than in the control workers, the arm-hand steadiness test being more discriminative than the eye-hand coordination test. Preclinical changes in psychomotor function can be detected independently of the presence of signs of renal dysfunction. No clear-cut relationships were found between the prevalence of abnormal psychomotor scores and the level of mercury in blood (HgB) or in urine (HgU). Increased prevalences of abnormal psychomotor scores seem however to occur for HgB between 1 and 2 g/100 ml and for HgU between 50 and 100 g/g creatinine. Therefore, a biologic threshold limit value of 50 g/g creatinine is proposed for urinary mercury to prevent the development of preclinical effects on the central nervous system. A similar critical HgU level based on renal dysfunction prevalences has been suggested in a previous study.This study was supported by a grant from the Commission of the European Communities  相似文献   
945.
Summary Glomerular filtration rate (GFR;51Cr-EDTA clearance), serum creatinine concentration and urinary excretion of prostaglandins were measured in 8 patients with systemic lupus erythematosus (SLE) before and after 2 weeks of treatment with acetylsalicylic acid (ASA). ASA 65 mg/kg or up to 4 g/daily was given as a sustained release preparation. The serum salicylate concentration ranged from 0.3 to 1.6 mmol/l. Serum creatinine after 1 and 2 weeks and GFR after 2 weeks of ASA treatment showed no significant changes. There was a clearcut decrease in urinary excretion of prostaglandins PGE2 and PGF2, by 44% and 50%, respectively. It is concluded that therapeutic doses of ASA do not cause deterioration of GFR in patients with SLE and normal or moderately reduced renal function.  相似文献   
946.
947.
Summary The effects of the competitive angiotensin II antagonist saralasin (1-sarcosine-8-alanine-5-isoleucine-angiotensin II) on renal function in healthy rats and in rats with myohemoglobinuric acute renal failure were studied. Acute renal failure was induced by an intramuscular injection of 50% glycerol (10 ml ·kg–1). Functional impairment of the glycerol treated animals consisted in a decrease of renal blood flow (electromagnetic flowmeter) and GFR and in an increase of urine volume and arterial blood pressure.In healthy rats saralasin (6 g·kg–1·min–1 i.v.) had no renal effects by itself but antagonized the angiotensin II (200 ng·kg–1·min i.v.) induced fall of renal blood flow and GFR and the increase of arterial blood pressure. Given to glycerol treated animals saralasin did not induce any change of arterial blood pressure, renal blood flow, GFR or the urinary excretion of fluid and sodium.Supported by Deutsche Forschungsgemeinschaft  相似文献   
948.
Behavioral data are reviewed that give evidence for an indiscriminate involvement of brain catecholamines (CA), especially dopamine (DA), in nervefunction, regardless of the time elapsed from their synthesis. Critical analysis of biochemical and pharmacological studies shows that a clear-cut distribution of brain catecholamines in two compartments [newly synthesized (NS) and main storage] is not at all established, and moreover that there is no adequate proof that the difference in turnover rates attributed to these two supposed pools is due to a preferential extraneuronal release of NS-CA during nerve function rather than to a preferential (nonfunctional) intraneuronal deamination of NS-CA, or at least of NS-DA.  相似文献   
949.
The case of a patient with reappearing stupor, accompanied by auditory hallucinations and persecutory ideas during the periods and not with alternating excitement, is reported. After 24 years of neuroleptics medication with little effect, the lithium carbonate regimen was started, which showed a remarkable prophylactic effect. The implications of lithium carbonate treatment for recurrent psychosis are discussed.  相似文献   
950.
目的 研究芦荟凝胶原汁及其多糖对小鼠免疫功能的影响。方法 芦荟凝胶原汁及其多糖饲喂小鼠,测定各组小鼠的脾脏和胸腺重量、巨噬细胞吞噬功能及淋巴细胞数量与功能。结果 与对照组相比芦荟凝胶原汁及其多糖溶液均使小鼠免疫器官脾脏、胸腺重量有不同程度的增加;小鼠腹腔巨噬细胞的吞噬百分数分别从17.33%增长至53.17%和38.57%,吞噬指数分别从0.28增长至1.23和0.69;与对照组相比小鼠外周血液中的T淋巴细胞数量和功能也有显著增加。结论 初步说明两者对小鼠的机体免疫功能均有一定的增强作用,且效果前者优于后者。  相似文献   
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