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991.
The cell-free medium of isolated human glomeruli exhibited a procoagulant activity and stimulated thromboxane (TXB2) synthesis in human platelets in a dose-dependent manner. The amount of TXB2 measured was 16-fold higher than what could have been predicted (TXB2 synthesized by the platelets under control conditions plus TXB2 present in the glomerular supernatant). The lipid extract of the glomerular supernatant and its purified fraction including the fatty acids was still able to stimulate--although at a lesser degree--TXB2 synthesis in platelets. Stimulation was abolished after treatment of this fraction by charcoal or albumin. Gas chromatography/mass spectrometry analysis demonstrated the presence in the purified glomerular fraction of several long-chain saturated or monoenoic fatty acids at a total concentration of 80 microM with the following order of abundance: stearic, palmitic, myristic and oleic acids. Addition to human platelets of these same exogenous synthetic acids resulted in a dose-dependent stimulation of TX synthesis. It was maximum with three or four fatty acids tested in combination, but still present with myristic acid used separately. Arachidonic acid was absent in the glomerular supernatant. Thus the stimulation observed could not be related to a greater availability of substrate. Fatty acids did not act on platelets through a non-specific detergent effect since addition of high doses of detergents inhibited TXB2 formation in platelets. The combination of fatty acids from glomerular origin identified in the present study represents a novel factor involved in the control of intracapillary hemostasis, but different from the procoagulant activity common to many tissues.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
A general overview of the literature concerning the development of diabetic neuropathic arthropathy is discussed. A case report is presented dealing with spontaneous fractures of the lesser metatarsal in a patient with an amputated hallux and peripheral neuropathy secondary to diabetes mellitus. 相似文献
993.
The authors' 5-year experience in the management and care of prostatic carcinoma are summarized. Their method differs essentially from earlier practice. They have found a new diagnostic and therapeutic method by introducing the TECO irradiation therapy, extensively using bone scintigraphy, by introducing cytostatics, extensively applying the prostate-specific acid phosphatase and by performing rectal biopsy of the prostate. They describe their own observations on the diagnostics and therapy of prostatic carcinoma. They stress that none of the therapies is the method of choice, the use of the various kinds of treatment are defined by strict indications. They state that care of prostatic cancer patients is highly important because only observation of the course of the disease may ensure the evaluation of treatment results and the indication of the adequate therapeutic method. 相似文献
994.
H. Sueki 《Journal of cutaneous pathology》1987,14(4):217-222
To evaluate diabetic microangiopathy in the subcutaneous fatty tissue objectively and to clarify the relation between pathogenesis of membranocystic lesion (MCL) and diabetic microangiopathy, specimens obtained from 23 diabetics and 23 nondiabetics were examined histologically. Ten of 23 diabetics and 7 of 23 non-diabetics were examined electron microscopically. Using electron micrographs measurements were made of the following areas; entire microvessel section, basal laminae, luminal space, endothelial cells, pericytes, and we scored the following findings: veil cells, cellular debris and vacuoles in the thickened basal laminae, abnormal densities of the endothelial cells. In diabetics, the area of luminal space was smaller and the area of basal laminae was larger than those of non-diabetics. Scored assessment of the veil cells, cellular debris and vacuoles in the thickened basal laminae were statistically significant in diabetics. Veil cells around the subcutaneous microvessels were less frequent and possessed fewer cytoplasmic processes than those around the dermal microvessels. Histologically, MCLs were frequently demonstrated in skin disorders resulting from diabetic microangiopathy, including 3 cases of pigmented pretibial patches, and 1 case of diabetic bulla. MCLs were more frequently demonstrated in diabetic cases with retinopathy, neuropathy, and nephropathy than those without complications. MCLs were detected only on the shins and the feet. MCLs were more frequently seen in cases with larger area of basal laminae than those with smaller area of basal laminae in morphometric measurement of electron micrographs. The present studies suggest that microangiopathy in the subcutaneous tissue is a pathological feature of diabetes mellitus and is a contributory factor to the formation of MCL. 相似文献
995.
996.
997.
Circulating immune complex levels in patients with schistosomiasis and complications 总被引:3,自引:0,他引:3
A M Ghanem F N Boctor S Bassily H Shaheen A Ahmed L Garges 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1987,81(5):773-777
Circulating immune complexes (CIC), adult schistosome antibody, and total immunoglobulin concentrations were estimated in sera from 35 chronic Schistosoma mansoni patients with different infection intensities and different pathological complications. High CIC levels were present in about one-third (10/35) of the sera. Most of the patients (9/10) with elevated CIC levels also had hepatomegaly or hepatosplenomegaly. This finding is significant in the pathogenesis of schistosomal liver fibrosis and may also apply to other liver diseases, especially cirrhosis. No correlation was found between infection intensity as judged by stool egg counts and CIC levels. A reverse relationship was observed between the level of anti-adult worm IgG and CIC levels. CIC levels were elevated within 7 and 28 days after treatment in most patients. Hypergammaglobulinaemia was detected in most sera. 相似文献
998.
To evaluate the relative contribution of insulin binding and postbinding defects of glucose utilization in peripheral tissue during normal and diabetic pregnancy, we have studied the in vitro insulin action of isolated adipocytes from eight nondiabetic pregnant women and nine pregnant women with insulin-dependent diabetes mellitus who were undergoing cesarian section. The pregnant women were compared with a matched group of normal nonpregnant women undergoing gynecologic surgery. Insulin binding to adipocytes measured at tracer insulin concentration was reduced by 45% (P less than 0.01) in normal pregnant women and by 30% (P less than 0.02) in pregnant women with diabetes. In contrast, no changes were found between the three groups in insulin binding to pure monocytes and erythrocytes. The glucose transport system in fat cells from both groups of pregnant women was characterized by impaired maximal (P less than 0.05) and half-maximal (P less than 0.05) response to insulin. When fat cell glucose metabolism was studied, pregnant diabetic women exhibited decreased basal lipogenesis (P less than 0.05) and decreased maximal responses of lipogenesis and glucose oxidation to insulin stimulation (P less than 0.05). Similar but less pronounced abnormalities were seen in glucose metabolism of adipocytes from nondiabetic pregnant women. In conclusion, both in late normal and diabetic pregnancy, insulin binding to adipocytes is significantly reduced and accompanied by decreased insulin sensitivity and reduced maximal insulin responsiveness of glucose transport and by impaired basal and maximally insulin-stimulated glucose metabolism. 相似文献
999.
1000.
S. Ahmed A. L. Sparnon J. P. Savage H. A. Boucaut A. J. Smith 《ANZ journal of surgery》1986,56(9):675-680
One hundred and one children over 1 year of age have had surgery for pelviureteric obstruction over an 11 year period. The common clinical features were abdominal pain, urinary infection or haematuria, but number presented as an incidental finding. Less commonly, the patients presented with an abdominal mass or with hypertension. The diagnosis was usually made on intravenous pyelography (IVP) but in the latter part of the series, renal nuclide scan (RNS) and ultrasonography (US) were preferred. Ninety–three patients had unilateral pyeloplasty, three had bilateral pyeloplasty and five had nephrectomy or heminephrectomy. Whereas initially nephrostomy drainage was used in the majority of patients after pyeloplasty, trend away from nephrostomy evolved in the latter part of the series. With experience, the incidence of postoperative complications was also reduced and there was reduction in the period of hospitalization. Clinical results were consistently satisfactory. Postoperative assessment after pyeloplasty was made by IVP and/or RNS and also US. A review of these investigations showed that RNS provided more factual information of the result when compared with the IVP. 相似文献