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71.
Four hundred seventy blood access procedures performed on 170 dialysis patients during the period 1962-1975 have been analyzed according to survival of access with respect to age, sex and cause of failure. Subcutaneous forms of blood access have a significantly longer life and are more free of complications than external shunts. Although the mode of access can now be tailored to the individual patient, the arterio-venous fistula remains the least expensive and simplest surgical procedure. It should therefore remain as the first choice of access for most patients.  相似文献   
72.
Striated muscle fibers (or cells) were observed in three of the six swine pineal glands. The muscle fibers occurred in clusters of several fibers about the parenchymal blood vessels. They were in general poorly developed, lacked regular cross striations and were not readily recognized histologically. The muscle fibers were, however, easily identified on electron microscopy because of the myofilaments they contain. In most of the muscle fibers, the myofilaments were arranged in ill-defined, disorderly bundles and rarely formed well-defined myofibrils and sarcomeres. The sarcotubular system was also poorly developed and triads were sparse and randomly scattered. Leptomeres were observed in several muscle fibers. The source of the muscle fibers in the pineal glands is not well understood and, whatever the source may be, the muscle fibers seem to remain poorly developed in the pineal glands.  相似文献   
73.
In concentration of testosterone and dihydrotestosterone in blood plasma was determined in 21 healthy females and in 37 patients with breast cancer. The method of competitive binding of tritium labelled testosterone and dihydrotestosterone by specifically binding beta-globulin was employed. It was found that healthy females fail to show any age variations in the concentration of the hormones under investigation in blood. In menopausal patients testosterone concentration tends to decrease in cancer dissemination.  相似文献   
74.
This study was undertaken to learn the significance of focal glomerular sclerosis in children who have nephrotic syndrome. Tissue obtained by percutaneous renal biopsy 10-15 years previously was re-examined. Initially, two of the 29 biopsy specimens contained focal segmental hyalinosis or sclerosis and five of the 29 had focal glomerular obsolescence. The paraffin blocks were serially sectioned and examined. Following this procedure, seven of the 29 biopsies had focal segmented hyalinosis and 16 of the 29 had focal glomerular obsolescence. The percentages of focal segmental hyalinosis and focal glomerular obsolescence were recorded. Only those patients whose focal segmental hyalinosis exceeded 2% progressed to renal failure. Age-matched autopsy material from patients dying without renal dysfunction was used as a control. Focal glomerular sclerosis was seen in 75.8% of the control specimens, although few glomeruli within each specimen were involved. Focal glomerular sclerosis may be found normally; it may be found in nephrotic children who do not develop renal failure. The quantification of sclerotic lesions may be of prognostic significance in childhood nephrosis.  相似文献   
75.
In the paper, a clinical experience with treatment of intestinal paresis in 545 children, aged from 1 day to 13 years, including 225 children operated upon for peritonitis is summarized. The authors differentiate 3 stages in the development of intestinal paresis depending on the degree of intensity of systemic and local disturbances. The employed methods of treatment in intestinal paresis were classified by the principle of their effect as 3 groups. Application of some or other method of the paresis therapy is determined by the stage of its development. In treatment of postoperative intestinal paresis a continuous peridural blockade is considered to be the method of choice. Utilization of the latter enabled the authors to reveal a number of postoperative complications: mechanic intestinal obstruction, incompetent anastomosis, etc.  相似文献   
76.
Effects of some phenols and polycyclic aromatic hydrocarbon derivatives on benz(a)-pyrene metabolism have been studied in the microsomal system isolated from the mouse embryonic cell cultures. The rate of benz(a)pyrene metabolism was shown to depend on the structure and concentration of the agents added. The toxic effect of benz(a)pyrene was summed up with that of either agent studied (except ionol) added simultaneously to the cell culture.  相似文献   
77.
78.
Serum lysozyme activity was measured in groups of untreated patients with malignant melanoma, hyperneophroma and breast carcinoma. Significant elevation of serum levels of the enzyme was confined to patients with localized disease. In the presence of metastatic disease such elevation was not detected. The rise in serum lysozyme activity was not due to renal damage or any infective process and in the case of malignant melanoma was shown to be associated with infiltration of the tumour mass by macrophages. In vitro studies demonstrated that the macrophages resident in a tumour mass are responsible for relasing lysozyme in large amounts. It is proposed that the elevation of serum lysozyme in these cases may be an indicator of macrophage-mediated host resistance and that the measurement of macrophage products such as lysozyme in the extracellular fluid may under well defined conditions provide useful clinical information concerning host reactions.  相似文献   
79.
Phagocytic cells were obtained from children at ages comparable to those at which the disease is most commonly seen during pregnancy. The effect of P-HCl on the phagocytic action of these cells on opsonized red blood cells was studied in vitro.  相似文献   
80.
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