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11.
The role of the renin angiotensin system for the regulation of kidney function in diabetes mellitus is uncertain. Results from studies in diabetic animals suggest that a reduced activity in this system contributes to the renal hyperperfusion and hyperfiltration in diabetes. The renal sensitivity to angiotensin II in diabetic patients is also unknown. Changes in renal hemodynamics were measured after infusion of two low doses of angiotensin II in ten young type 1 diabetic patients without complications and in ten healthy controls. The renin and angiotensin II levels were found to be the same in both groups. The baseline glomerular filtration rate was higher in the diabetics. During the highest angiotensin II dose, the 51Cr-EDTA and PAH clearance decreased 14 +/- 15 and 157 +/- 118 ml/min in the diabetics and 14 +/- 15 and 146 +/- 109 in the controls respectively. The changes in blood pressure and renal vascular resistance or sodium excretion did not differ between the groups. A malfunction of the renin angiotensin system is thus unlikely as a cause of the glomerular hyperfiltration in type 1 diabetes.  相似文献   
12.
At our center, since 1982, a body mass index (BMI) of less than 30 has been a prerequisite for placing a patient on the waiting list for renal transplantation. This decision was made because obese transplant recipients seemed to have a less than favorable post-transplant outcome. The aim of this study was to evaluate whether this requirement is still justified. Forty-six patients with a BMI above 30 underwent primary cadaveric renal transplantation between 1972 and 1993. For each of these obese patients, five consecutive non-obese (BMI 20–25) control patients were selected. Patient and graft survival, causes of graft loss, and acute rejection rate were evaluated for the two patient groups before and after the year 1982. Within the first 30 post-transplant days, one patient (2 %) and 11 grafts (24 %) were lost in the group of obese patients whereas seven patients (3 %) and 36 grafts (16 %) were lost in the control group. Among the obese patients, renal circulatory complications were a major cause of graft loss. In the period 1973–1981, the 1-year patient survival rate was 65 % among obese patients versus 75 % among controls from 1982 to 1993, this was 90 % versus 93 %. From 1973 to 1981, the 1-year graft survival rate was 25 % among obese patients versus 53 % among controls (P < 0.05); from 1982 to 1993, it was 68 % versus 84 % (P = NS). Multivariate analysis showed that the immunosuppressive regimen, age of the patient, BMI, and cold ischemia time of the graft had a significant influence on graft survival. The acute rejection rate within the first 30 days was 28 % among obese patients and 35 % among controls (P = NS). We conclude that a BMI below or equal to 30 is still justified as a prerequisite for placement on the waiting list for renal transplantation, for despite an overall improvement, the outcome of renal transplantation in obese patients remains worse than that in non-obese patients. Received: 3 February 1997 Received after revision: 4 April 1997 Accepted: 8 April 1997  相似文献   
13.
Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness.  相似文献   
14.
By using stereotaxic surgical techniques, ventral mesencephalic tissues from aborted human fetuses of 8 to 10 weeks' gestational age were implanted unilaterally into the striata in two patients with advanced Parkinson's disease. The patients were treated with a cyclosporine, azathioprine, and steroid regimen to minimize the risk for graft rejection. They were examined for 6 months preoperatively and 6 months postoperatively and continued to receive the same doses of antiparkinsonian medication. There were no significant postoperative complications. No major therapeutic effect from the operation was observed. However, in the clinical tests, both patients showed small but significant increases of movement speed for repeated pronation-supination, fist clenching, and foot lifting. The rate of walking also increased in the one patient tested. For both patients, there was an initial worsening postoperatively, followed by improvement vs preoperative performance at 1 to 3 months. Both patients also showed significant improvement in the magnitude of response to a single dose of levodopa (L-dopa), but there was no increase in the duration of drug action. The motor readiness potential increased in both patients postoperatively, primarily over the operated hemisphere. Neurophysiological measurements also showed a more rapid performance of simple and complex arm and hand movements on the side contralateral to transplantation in one patient at 5 months postoperatively. Positron emission tomography demonstrated no increased uptake of 6-L-(18F)-fluorodopa in the transplanted striatum at 5 and 6 months. Taken together, these results suggest that the fetal nigral implants may have provided a modest improvement in motor function, consistent with the presence of small surviving grafts. Although our results support further scientific experimentation with transplantation in Parkinson's disease, widespread clinical trials with this procedure are probably not warranted at this time.  相似文献   
15.
Cardiac function and changes following surgery was studied with computerized M-mode echocardiography in 12 patients with volume load of the left ventricle. Half of them had congenital lesions, the other half aortic regurgitation. Left ventricular (LV) shortening fraction and LV ejection time were significantly reduced postoperatively and came close to normal mean values. Also cardiac output and LV diameters normalized or at least started its normalization. The computerized values for rates of decrease and increase of left ventricular diameter were reduced postoperatively (p less than 0.01 and p less than 0.05 respectively) compared to elevated preoperative values. The study shows that relief of volume load on the left ventricle immediately leads to normalization of left ventricular function, especially if the myocardium was intact preoperatively.  相似文献   
16.
Cigarette smoking may alter bronchial inflammation in asthma. Multicolour immunohistofluorescent examination on bronchial cryosections was used to examine bronchial inflammatory cell infiltrate in patients with occupational asthma. Monoclonal antibodies to CD3, CD4, CD8, T-cell receptor-delta1, CD68 and human leukocyte antigen-DR were combined to identify T-cell subsets and macrophages in bronchial biopsies from 20 workers with occupational asthma (12 smokers and eight nonsmokers), 15 healthy workers (seven smokers and eight nonsmokers) and 10 nonsmoking, nonexposed controls. The increased subepithelial CD4+ T-cell density in nonsmoking asthmatics was not present in smoking asthmatics, who had the lowest CD4+ T-cell density of all groups. The decreased subepithelial CD4+ and CD8+ T-cell density correlated with a reduction in lung function, as measured by percentage predicted forced expiratory volume in one second, in smoking asthmatics only. Although smoking asthmatics had a significantly increased number of intraepithelial CD8+ T-cells and macrophages compared with nonsmoking asthmatics, the proportion of gammadelta-T-cells was significantly decreased in both asthmatic groups. Smoking asthmatics had a distinctly different distribution of T-cell subsets compared with nonsmoking asthmatics. The accumulation of subepithelial CD4+ T-cells, which was observed in nonsmoking asthmatics, appeared to be inhibited in smoking asthmatics, suggesting a smoking-induced bronchial immune modulation, at least in occupational asthma in the aluminium industry.  相似文献   
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OBJECTIVE: The purpose of this study was to obtain information about how patients perceive the health care delivered in an emergency department. SETTING: Patients who visited the ED at a Swedish university hospital during the daytime on Monday through Friday during a four-week period and were expected to be discharged from the ED after their visit were included in the study. Other criteria for participation were the patients' mental and physical abilities to fill out a questionnaire. STUDY DESIGN: One hundred eighty-seven patients (110 women and 77 men) classified as orthopedic, gynecologic, internal medical, surgical, or neurologic patients evaluated their perception of the health care delivered in the ED by filling out a questionnaire after arrival and before discharge. MEASUREMENTS AND MAIN RESULTS: The perceptions of the care received were on average quite positive. This was supported indirectly by the fact that scored pain, strength, calmness, and despair changed in a positive direction during the ED stay. However, a pattern of varying satisfaction appeared when the patients were dichotomized into three groups according to how they had perceived their first information on arrival. Fourteen percent of the patients had received exact information, 20% were partly informed, and 66% had received no information about what was going to happen to them next. Those who received the most information at the time of arrival at the ED were more satisfied with the general treatment (P less than .05), respect (P less than .01), and attitude (P less than .05) later shown by the staff as well as with the information given later (P less than .05) than were the patients who had received no information at all on arrival. The general evaluation of the ED was more positively (P less than .001) scored by the patients who received the most information (they were more satisfied) compared with the other two groups. CONCLUSION: The information given to patients on arrival at the ED may be important to a positive perception of the care given during their stay.  相似文献   
20.
Although rupture of the extensor pollicis longus (EPL) tendon is a well-known complication of distal radial fractures, a number of patients rupture the EPL because of other conditions. We have retrospectively studied the aetiology of 27 ruptures of the EPL in 26 consecutive patients. Of 19 patients with injured wrists 12 had distal radial fractures, five had blunt trauma, and two had stab wounds that resulted in rupture. In the radial fractures operated on, the EPL rupture was caused by chafing against a dorsal plate (n = 2) or wear against the pins of an external fixator (n = 2). Six patients were taking steroids for systemic diseases and in two cases a local steroid injection was given just before the rupture. We conclude that previous injury is the most common cause of rupture of the EPL. but that rheumatoid arthritis or local or systemic steroids, or both, are also important aetiological factors. Seven patients had an iatrogenic cause for their rupture.  相似文献   
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