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CONTEXT AND OBJECTIVE: The safety and efficacy of drug-eluting stents reduce the need for surgical revascularization. The objective of the present study was to investigate whether paclitaxel or rapamycin-eluting stent are effective in avoiding the need for coronary-artery bypass grafting. METHODS: This was a systematic review of the literature using the methodology of the Cochrane Collaboration. The type of study considered was controlled randomized trials; the type of intervention was drug-eluting or bare-metal stents; and the main outcome investigated was coronary-artery bypass grafting. RESULTS: The ten studies included in this systematic review did not show any statistically significant difference between the drug-eluting stents and the bare-metal stents with regard to the outcome of coronary-artery bypass grafting (confidence interval: 0.31 to 1.42). CONCLUSION: The surgical revascularization rate was not reduced by the use of drug-eluting stents. 相似文献
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O Crivello J G Luz J B Lemos J R Rezende 《Revue de stomatologie et de chirurgie maxillo-faciale》1989,90(2):100-103
Statistical analysis of 550 isolated maxillo-facial fractures is presented. Data obtained illustrated the important number of maxillo-facial fractures in Sao Paulo, the automobilistics accidents were responsible for most maxillo-facial trauma, the jaw and the malar were more predominant than the others structures and the conservative treatment was the most used one. 相似文献
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L. Freire-Maia A. D. Lemos Fernandes A. D. Azevedo Suely B. Oliveira W. Dias da Silva 《Inflammation research》1973,3(5):326-331
The intravenous injection of rabbit anti-rat kidney serum in rats produces, with a latency of 30 to 60 seconds, the triad sinus bradycardia (or S-A blockade), systemic hypotension and apnea. Recordings of the intracardiac pressures showed a rise in the right and a simultaneous fall in the left ventricular pressure, 30 to 60 seconds after the serum injection. These initial effects were followed by pulmonary edema and death. Bilateral vagotomy prevented the bradycardia and apnea, but not the intracardiac changes, edema and death. Atropine also prevented the bradycardia, but not the apnea, edema and death. Experiments using alpha and beta adrenergic blocking agents seem to indicate that the edema is not caused by the release of catecholamines. It is suggested that the edema could be explained by a rise in the pulmonary capillary pressure, due to the antigen-antibody reaction. The triad bradycardia, systemic hypotension and apnea seems to be the first sign of the pulmonary edema, is reflex in nature, and is assumed to be due to stimulation of J receptors in the lungs, by a mechanical effect (edema). Phenylbutazone and acetylsalicylic acid give a partial protection against the pulmonary edema. Ultramorphological observations of lungs with edema were described. 相似文献
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Anderson RA; Wallace AM; Kicman AT; Wu FC 《Human reproduction (Oxford, England)》1997,12(8):1657-1662
Administration of supraphysiological doses of testosterone to normal men
causes inhibition of spermatogenesis, but while most become azoospermic,
30-55% maintain a low rate of spermatogenesis. We have investigated whether
there are differences in endogenous androgen production, of testicular and
adrenal origin, which may be related to the degree of suppression of
spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m.
injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic,
while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a
specific testicular product, was reduced to <10% of pretreatment values,
with no differences between the groups. Similar results were obtained for
other markers of testicular steroidogenesis. Urinary and plasma adrenal
androgens were also reduced during TE treatment: a statistically
significant decrease in both (P < 0.001 and P < 0.05 respectively)
was seen in the azoospermic but not oligozoospermic responders. These
results suggest that testicular steroidogenesis is decreased to <10% by
the administration of supraphysiological doses of exogenous testosterone.
Differences in the degree of ongoing steroidogenesis in the testis do not
appear to account for incomplete suppression of spermatogenesis, thus
differences in androgen metabolism may underlie this heterogeneous
response. A small but significant reduction in secretion of adrenal
androgens was also detectable, the relevance of which is unclear.
相似文献
8.
Passive immune hemolysis for detection of heat-labile enterotoxin produced by Escherichia coli isolated from different sources.
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M B Serafim A F Pestana de Castro M H Lemos dos Reis L R Trabulsi 《Infection and immunity》1979,24(3):606-610
Fifty-one strains of Escherichia coli isolated from humans, swine, food, and water and identified as enterotoxinogenic by the Y-1 adrenal cell assay, were examined for heat-labile enterotoxin (LT) production by the passive immune hemolysis test. Cholera antitoxin, anti-choleragenoid and anti-LT were used as antisera. Cholera antitoxin was much more potent than anti-choleragenoid and LT antiserum in the detection of LT-positive strains. All strains isolated from pigs and sausage were negative in tests made with LT antiserum. A few strains isolated from humans, food, and water also gave negative results. These data showed that the passive immune hemolysis test is not as efficient as the Y-1 adrenal cell assay in the detection of enterotoxinogenic E. coli strains. 相似文献
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Azeredo RA Watanabe IS Benigno MI Lemos JL Liberti EA 《Morphologie : bulletin de l'Association des anatomistes》2000,84(266):19-24
The characteristics of trabecular bone in human fetuses at seven to nine months of intra-uterine life were studied in the vestibular surface of the mental and body portions of the mandible. In the mental portion, many circular trabeculae joined by "bridges" were observed in the alveolar region (AR). In the 8-month old fetus are trabeculae with tortuous disposition in the medium region (MR). Oblique trabeculae with superior and inferior dispositions defining a triangular area (future mental fossae) are verified in 9-month old fetuses. Trabeculae circularly disposed and vascular foramina are present close to the apex of this area. In the basilar region (BR) some trabeculae obliquely oriented are observed disposed near to the mandibular symphysis. The longitudinal bundles of collagen fibers assume an antero-posterior direction. At 9-month age the vascular foramina range from 6 to 20 microns and the osteocyte lacunae ranging from 1 to 4 microns diameter, are present in mandibles from all ages examined. In the body portion the presence of circular trabeculae joined by "bridges" is the main characteristic of the AR. In the MR most of the trabeculae are circular and the longitudinal trabeculae of this region assume an antero-posterior direction. The laminar, antero-posterior and juxtaposed trabeculae lying parallel to mandible base are a characteristic of the BR. The bundles of collagen fibers exhibit the same pattern of the trabeculae. The vascular foramina of the BR are smaller than that of the precedent regions. In the body portion of the mandible from all ages examined the osteocyte lacunae range from 1 to 4 microns in diameter. 相似文献