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991.
de Caro R. Parenti A. Capitanio G. Ori C. Bracco F. Ricchieri G. L. 《Acta neurochirurgica》1990,104(1-2):73-76
Summary A vascular malformation, consisting of a venous vessel bridgeing the right inferior petrosal sinus and the anterior spinal veins, was found in the posterior fossa. The vessel presented a ring-like course around the right trigeminal root, and it was parallel and dorsal to the basilar artery. The malformation was associated with cutaneous and hepatic angiomas and peri-osteal lipomas. It had been clinically silent for 52 years, when it thrombosed causing death. The authors think that, within a general mesenchymopatic state, this is a result of the persistence of an embryonal cerebral venous pattern. 相似文献
992.
993.
994.
Previous studies showed that administration of dehydroepiandrosterone (DHEA) to lean and genetically obese Zucker rats reduced body weight. In the present experiments, the effect of DHEA treatment in rats with diet-induced obesity was evaluated. In experiment 1, male Sprague-Dawley rats (300 g) were fed a nonpurified diet (reference group) or a condensed milk-corn oil nonpurified diet [diet-induced obese (DIO) rats] for 7 wk. Then, 0.6% DHEA was included in the food of one-half of the DIO rats (DIO + DHEA rats). After 6 wk, DIO rats weighed 23% more and had greater fat pad weights, cell size and cell number than reference and DIO + DHEA rats. Brown fat mitochondrial respiration was similar in all groups. DIO rats had higher serum cholesterol and triacylglycerol concentrations than reference and DIO + DHEA rats. DIO + DHEA rats had lower serum insulin levels than DIO and reference rats. In experiment 2, male Sprague-Dawley rats (460 g) were fed either the nonpurified diet or the condensed milk diet for 8 wk. Condensed milk-fed rats were then divided into DIO and diet-resistant groups. One-half of the rats in each group were fed 0.6% DHEA for 2 wk. Body weights and serum glucose, insulin, triacylglycerol and triiodothyronine levels were lowered by DHEA treatment in all groups. Liver mitochondrial state 3 respiration rates per gram and per liver and peroxisomal beta-oxidation were higher in DHEA-treated than in control rats. In DIO rats, DHEA treatment appears to interfere with hyperplastic adipose tissue growth. In this strain of rats, DHEA appears to have hypolipidemic and hypoinsulinemic effects. 相似文献
995.
Fundus biomicroscopy as a clinical technique has been enhanced significantly by the addition of indirect view condensing lenses. The combination of this type of lens with a corneal contact element allows higher power and better stability so that a wider field can be obtained. The Panfunduscope of Schlegel and the Mainster retinal lens are examples of this design that have been successfully applied to both examination and to pan-retinal photocoagulation. Volk has recently introduced a new aspheric design indirect contact lens system which is higher in power and provides a wider field of view (125 degrees) than previously obtainable. This article describes the optical properties and use of the Quadraspheric lens. 相似文献
996.
Motorcycle injuries in Bermuda 总被引:2,自引:0,他引:2
S F Purkiss 《Injury》1990,21(4):228-230
Tourists who hire mopeds or motorcycles for personal use have a risk for accident. The incidence of tourist accidents in Bermuda was 1.57 accidents/1000 tourists evaluated over a 6-month period. The accident incidence increased as the tourist population got larger. Tourists of more than 40 years of age had the greatest increase in incidence for accident during this period. The risk of an injury requiring hospital stay was one patient for every 16,000 tourists visiting the island, and usually involved the fracture of an extremity. All accidents, major or minor, resulted in some form of skin injury. 相似文献
997.
Cellular receptors for matrix proteins in normal human kidney and human mesangial cells 总被引:9,自引:0,他引:9
In the present study we evaluated the distribution of cell adhesion molecules, referred as very late antigens (VLA), in the normal human kidney and in mesangial cells in culture (MC). In addition, we assessed the functional properties of VLA proteins on MC. Normal human kidney and MC were stained by immunoperoxidase with mouse monoclonal antibodies to VLA proteins. We demonstrated that VLA-3, a protein that binds FN, laminin and collagen, is the predominant VLA protein in the human glomerulus and on MC. VLA-3 is located in the mesangium and on the glomerular visceral epithelial cell and endothelial cell surfaces in contact with the glomerular basement membrane. VLA-1 was demonstrated in the glomerular mesangium and VLA-5, an FN specific receptor, was present in the mesangium on glomerular endothelial cells and on MC. VLA-2 and VLA-4 were not present in the normal glomerulus nor on MC. In functional studies we evaluated the binding of MC to FN coated surfaces and the binding and phagocytosis of FN coated fluorescent beads by MC. We showed that MC bind to FN coated surfaces and that the binding is inhibited by anti-FN antibodies, EDTA and peptides containing the amino acid sequence Arg-Gly-Asp (RGD). In addition, anti-VLA-5 but not anti-VLA-3 antibodies inhibited significantly the binding of MC to FN, MC demonstrated binding and phagocytosis of FN coated beads and, purified FN inhibited both phenomena. By affinity chromatography and immunoprecipitation we demonstrated that MC FN binding proteins and MC VLA proteins are composed of two distinct protein chains that have Mr characteristics similar to those of normal human fibroblasts VLA proteins. In conclusion, the glomerular distribution of VLA-3 suggests that this protein is primarily involved on the adhesion of glomerular cells to basement membranes and matrix. MC FN receptors (VLA-5) mediate the binding of MC to FN and could mediate the phagocytosis of FN coated antigen or immune complexes by mesangial cells. 相似文献
998.
High prevalence of NIDDM and impaired glucose tolerance in Indian, Creole, and Chinese Mauritians. Mauritius Noncommunicable Disease Study Group 总被引:4,自引:0,他引:4
G K Dowse H Gareeboo P Z Zimmet K G Alberti J Tuomilehto D Fareed L G Brissonnette C F Finch 《Diabetes》1990,39(3):390-396
Mauritius, a multiethnic island nation in the southwestern Indian Ocean, has one of the world's highest diabetes mortality rates. The prevalence of both impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) was investigated in 5080 Muslim and Hindu Indian, Creole (mixed African, European, and Indian origin), and Chinese Mauritian adults aged 25-74 yr who were selected by random cluster sampling. Based on a 75-g oral glucose tolerance test and World Health Organization criteria, the age-standardized prevalence of IGT was significantly greater in women (19.7%, 95% confidence interval [CI] 18.1-21.2) than in men (11.7%, CI 10.5-12.8). By contrast, the prevalence of NIDDM was similar in men (12.1%, CI 10.9-13.4) and women (11.7%, CI 10.5-12.8) for all ethnic groups combined. The sex difference in IGT prevalence was seen in all ethnic groups, but for NIDDM, the sex difference was not consistent across ethnic groups. However, age- and sex-standardized prevalence of IGT and NIDDM was remarkably similar across ethnic groups (16.2 and 12.4% in Hindu Indians, 15.3 and 13.3% in Muslim Indians, 17.5 and 10.4% in Creoles, and 16.6 and 11.9% in Chinese, respectively). Three new cases of diabetes were diagnosed for every two known cases. The high prevalence of abnormal glucose tolerance in Indian subjects is consistent with studies of other migrant Indian communities, but the findings in Creole and, in particular, Chinese subjects are unexpected. Potent environmental factors shared between ethnic groups in Mauritius may be responsible for the epidemic of glucose intolerance. 相似文献
999.
The effect of drug concentration and light on the compatibility and stability of cisplatin and fluorouracil in i.v. admixtures was studied. Two sets of admixtures were prepared in 0.9% sodium chloride injection in polyvinyl chloride bags--(1) cisplatin 200 micrograms/mL and fluorouracil 1,000 micrograms/mL and (2) cisplatin 500 micrograms/mL and fluorouracil 10,000 micrograms/mL. Half of the admixtures were protected from light. All admixtures were stored at room temperature (24-26 degrees C), and those admixtures not protected from light were stored under room fluorescent light. After visual inspection, the pH of each admixture was determined, and an aliquot was assayed for drug concentration using a stability-indicating high-performance liquid chromatographic assay. Over a four-hour period, no visual changes were observed and the pH changes observed were negligible. In admixtures containing the lower concentrations of cisplatin and fluorouracil, it took approximately 1.5 hours for the concentration of cisplatin to reach 90% of the initial concentration. By four hours (lower concentration range) and three hours (higher concentration range) after the admixtures were prepared, less than 75% of the initial cisplatin concentration remained. There was less than a 5% decrease measured in the fluorouracil concentrations over the observation time. Admixtures of cisplatin and fluorouracil in 0.9% sodium chloride injection at the concentrations evaluated in this study must be used within one hour of preparation, whether or not they are protected from light. Intravenous administration of fluorouracil and cisplatin by continuous infusion will require alternative approaches to mixing the two drugs in the same container. 相似文献
1000.
F Pithon 《Bulletin des sociétés d'ophtalmologie de France》1990,90(5):561-568
A new approach for the treatment of serious and/or uncurable glaucoma is proposed by the adjonction of a drain, cut in a crinotube, with micro-perforations and set in the classical opening of a trabeculectomy. In four years, for nine cases of particularly severe hypertonia, we observed one relative unsuccess, three real and stable improvements during two years and then with the necessity of local treatment (for rather young patients), and five clear and till today durable improvements. We have also observed a very good local tolerance for all cases, with never a persisting major hypotonia. This simple and efficient process seams susceptible to find its room in the treatment of severe hypertonia. 相似文献