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931.
Fifty renal biopsies were studied by immunoelectron microscopy after embedding in a partly hydrophilic polyacrylic resin (LR White). Immunofluorescence studies were carried out on frozen sections of parallel tissue samples. Polyacrylic embedding gave good preservation of the renal ultrastructure and precise localization of immunoglobulin and C3c antibodies within glomerular electron-dense deposits. Non-specific staining of plasma proteins within vascular lumina could easily be detected. There was good correlation between immunoelectron and immunofluorescence microscopy. Immunoelectron microscopy is a very sensitive method, which can detect small amounts of antigen. More cases were, however, positive by immunofluorescence than by immunoelectron microscopy. This discrepancy may be explained by difference in sample size, and by difference in resolution of morphological details (electron microscopy versus fluorescence microscopy).  相似文献   
932.
This prospective study examined the influence of long-term amiodarone therapy on the parameters of the signal-averaged ECG and their relation to simultaneously derived Holter monitoring data. For this purpose, 23 patients with angiographically confirmed dilated cardiomyopathy or coronary heart disease and high-grade ventricular arrhythmias, in whom an average of four class I antiarrhythmic drugs had proven ineffective, were stabilized on amiodarone. Before the beginning of therapy, as well as after 2 months and, subsequently, every 3 months, a resting ECG, a signal-averaged ECG by Simson's method, and Holter monitoring were performed. Compared to the initial measurement, we found a significant increase in the duration of the total filtered QRS complex from an average of 114 +/- 24 ms to 127 +/- 35 ms, while the change in voltage did not reach the significance level. The incidence of late potentials remained largely constant under amiodarone; 10 patients showed a constant late potential, 12 patients had no late potential, and one patient with coronary heart disease developed a new late potential. In the long-term follow-up, we ascertained a relatively high responder rate under amiodarone between 41% and 81%. No relation could be detected between the results of the signal-averaged ECG and those of 24-h Holter monitoring.  相似文献   
933.
In Hungary valve replacement is still a major indication for heart surgery in adults. In the Cardiovascular Surgical Clinic of Semmelweis Medical University of Budapest from 1976 to 1990 2435 patients were operated for valve disease. Majority of the cases had single (aortic n = 856, mitral n = 912) or double (aortic + mitral n = 513) valve replacement. Over this 15 years period there have been many alterations in patients characteristics and surgical technique as well. In spite of the increasing mean age of patients the operative mortality has decreased (in the last 5 years period it was 2.7%, 5.5% and 7.9% in the three groups respectively). At the same time the number of patients requiring valve re-replacement or combined valve + coronary procedure has increased. The use of bioprosthetic valves has fallen below 10 percent from the 60--80 percent observed between 1976--1980. The analysis showes excellent surgical results in the field of valve replacement in Hungary.  相似文献   
934.
The neutron capture reaction 10B(1n,4He)7Li produces two energetic particles, 4He2+ and 7Li3+ that are strongly cell toxic. Due to the short range of these nuclear fragments (5-9 microns) mainly those cells that have bound or internalized a 10B-containing substance are growth-inactivated. The most critical and difficult step in an efficient boron neutron capture therapy (BNCT) is the tumour targeting. It is today possible to synthesize a large number of boron compounds and conjugate them to tumour-seeking macromolecules, such as monoclonal antibodies or different polypeptides. The boron-containing substances presently considered for therapy are sulfhydryl boron hydride (BSH) and boron-phenylalanine, (BPA) for the treatment of gliomas and malignant melanomas respectively. Other boronated compounds considered are ligands for receptor-amplified tumour cells, antibodies for tumour cells with specific antigens and thioureas for treatment of melanotic melanomas. The required boron concentration is given by the relative dose due to neutron capture in 10B and that of the competing capture reactions in nitrogen and hydrogen. Capture in nitrogen produces protons with a range of about 10-11 microns and this gives a radiation dose to all cells in the neutron activated area. Calculations show that the local concentration of 10B near the critical radiation target, DNA, must be higher than 10 ppm (10 micrograms/g). Increased emphasis will be put on the development of combinations of treatments that fulfil the requirements for attacking the microscopic spread of the tumour.  相似文献   
935.
936.
During a period of 20 weeks 18 female patients with fibromyalgia participated in a 60-minute exercise program twice a week. A control group, comprising 17 patients, was told not to change their physical activity level. Eleven patients in the training group and fourteen in the control group completed the study. The results at entry were compared to those after 20 weeks, as well as being compared to the results of the control group. No statistically significant changes or differences in general pain, pain coping and fatigue were seen after 20 weeks. Improved dynamic endurance work performance for the upper extremity was found, however, in the training group, measured as the strength of the first (p = 0.01) and the last repetition (p = 0.003). These results differed from the results of the control group (p = 0.02 and p = 0.003). It is concluded that fibromyalgia patients may undergo low-intensity dynamic endurance training without experiencing exacerbation of their general pain and fatigue symptoms.  相似文献   
937.
Changes in whole blood viscosity associated with hematocrit could be one of the pathways along which the cardiovascular disease (CVD) risk factors affect these diseases. Therefore, we studied in a nationwide survey comprising 514 apparently healthy Dutch elderly men and women aged 65-79 the possibility of any association between hematocrit and CVD risk factors (tobacco smoking, serum cholesterol, body mass index and blood pressure). Among men, diastolic blood pressure and total serum cholesterol were positively associated with hematocrit in both bivariate and multivariate regression analysis, whereas positive associations of hematocrit with body mass index and smoking were only significant (p < 0.05) in bivariate analysis. Among women, hematocrit was positively associated with body mass index and smoking. Except for smoking, which was associated with the mean corpuscular volume of the erythrocytes, hematocrit was positively correlated with hemoglobin and the number of erythrocytes. It is concluded that hemorrheological aspects should be considered when studying CVD among elderly people.  相似文献   
938.
Six methods for detecting domestic infestations by triatomine bugs were compared in the rural community of Amamá, north-west Argentina. An average of three pairs (range, 2-5 pairs) of sensor boxes and sheets of pink typing-paper were tacked to the walls of human sleeping areas in 45 houses for 30 days and then inspected by a two-man team. Triatoma infestans bugs were collected in bedrooms by a different two-man team aided by a flushing-out agent both before and after application of sensing devices. Finally, knockdown collections of bugs after application of one insecticide fumigant canister per bedroom were also made. The proportion of houses with evidence of current domestic bug infestations that were detected by the various methods were as follows: sensor boxes (95.3%), reports of householders (88.4%), knockdown (87.8%), paper-sheets (86.0%), and flushing-out (69.8-76.7%). The detectability of infestations, irrespective of the method used, increased with the density of the bugs. At low or intermediate bug densities, individual sensor boxes were more sensitive than their matched paper-sheets, but at any bug density there were no significant differences between the pooled results for all the boxes and for all the paper-sheets in the house. On average, each sensor box recorded 2.25 times more triatomine faecal smears than its matched paper-sheet, and this relation increased with the density of bugs in the house. Both sensing devices were effective at monitoring unsuccessful attempts of peridomestic triatomine populations to colonize houses.  相似文献   
939.
Histological malignancy grading and its correlation to prognosis were retrospectively investigated in 303 cases of squamous cell carcinoma of the vulva. A scoring system based on several variables is suggested. The scores and the individual histological variables were tested along with clinical factors with a view to predicting survival. Various histological variables including mode of invasion, depth of invasion and nuclear polymorphism, as well as the sum of the scores were good predictors of survival. The study revealed a significantly better survival rate in stage III if no metastases were suspected. An age factor was also found showing that cancer of the vulva has a worse prognosis in older women.  相似文献   
940.
The effects of magnesium were compared with those of placebo in a randomized double-blind controlled study of 58 patients with pregnancy-induced hypertension, of whom 27 received magnesium and 31 placebo. Twenty patients in each group were nulliparas. The treatment comprised 48 h of either intravenous magnesium or placebo infusion followed by daily oral magnesium or placebo tablets until one day after delivery. Magnesium supplementation significantly reduced maternal mean arterial blood pressure (MAP). The gestational age at delivery was the same in both groups, whereas the relative fetal birth weight among nulliparas was reduced in the placebo group. Unbalanced analyses of variance suggested an influence of magnesium supplement on birth weight. The infants in the magnesium supplemented group spent fewer days in the neonatal intensive care unit. There were no perinatal deaths. Magnesium appeared to be beneficial in the management of pregnancy-induced hypertension. The better outcome associated with magnesium supplementation may not have been due to reduction of MAP and further studies are needed to clarify whether magnesium influences birth weight.  相似文献   
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