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BACKGROUND The safety of the lipodissolution procedure for the cosmetic treatment of fat is unknown.
OBJECTIVES The objective was to determine the subcutaneous tissue effects of phosphatidylcholine solubilized with deoxycholate (PC/DC) in rats and a human volunteer.
METHODS Rats were treated subcutaneously three times with 50, 300, or 600 μL of PC/DC formula on the abdomen in a chronic study (30 days). A human volunteer undergoing elective liposuction was similarly treated. Cell membrane lysis, cell viability, and histologic status were determined on fresh biopsies of subcutaneous fat from the injection sites.
RESULTS PC/DC dose-dependently reduced membrane integrity and cell viability. Histologic alterations induced by PC/DC included fibroplasia, bandlike fibrosis in the region of the cutaneous muscle, and partial muscle loss. The highest dose caused widespread fat necrosis, fat cyst formation, and necrotic changes of the walls of small blood vessels. Histologic sections of subcutaneous tissue from the human volunteer showed dose-dependent panniculitis, fat cysts, and vessel necrosis. DC (2.5%), tested for comparison in the rat, exerted membrane and histologic effects similar to those of PC/DC. Solvent controls caused negligible alterations.
CONCLUSIONS Injection lipolysis with PC/DC causes tissue fibrosis and necrosis of adipose and vascular tissues in rat and man, making the long-term safety of PC/DC for nonsurgical treatment of subcutaneous fat deposits uncertain.  相似文献   
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The purpose of this study was to determine the influence of polarity reversal on DFT in patients undergoing implantation of nonthoracotomy defibrillators with biphasic shocks. Previous studies have shown higher defibrillation efficacy with using the distal electrode as anode in implantation of nonthoracotomy defibrillators and monophasic shocks. However, it is as yet unclear whether biphasic shock defibrillation will also be influenced by polarity reversal. Using a transvenous lead system with a proximal electrode in the superior caval vein and a distal electrode in the RV apex, 27 patients undergoing defibrillator implantation were randomized to DFT testing with "initial" (distal electrode = cathode) or "reversed" polarity (distal electrode = anode). Defibrillation energy was reduced stepwise until defibrillation failure occurred. At this point, polarity was switched and testing continued until the lowest energy requirement was determined for both polarities. With reversed polarity, DFT was 11.1 ± 5.7 J versus 13.3 ± 5.8 J with initial polarity (P = 0.033). This means a 17% reduction of the DFT. In 10 patients, the threshold was lower with reversed, whereas in 3 patients it was lower with initial polarity. In conclusion, changing electrode polarity in transvenous implantable defibrillators with biphasic shocks may significantly influence defibrillation energy requirements. Therefore, polarity reversal should always be attempted before considering patch implantation.  相似文献   
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A population study of alpha-keto acid reductase   总被引:1,自引:1,他引:0  
An electrophoretic survey of 509 individuals of Japanese, Mexican American, American Negro, Eskimo, Amerindian and Anglo-American origin failed to reveal genetically determined variation at the alpha-keto acid reductase locus by starch gel electrophoresis. Additional screening of 232 individuals by thin layer isoelectric focusing in polyacrylamide gels detected a single phenotype. Interspecific variation at the alpha-keto acid reductase locus is clearly resolved using either method. These results indicate that the alpha-keto acid reductase locus is monomorphic in most human population groups despite earlier results suggesting the existence of genetic polymorphism.  相似文献   
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We report on an adrenal carcinoma growing via the inferior venacava into the right atrium and prolapsing into the right ventricle.A patent foramen ovale determined the pathophysiological andclinical appearance. Instead of an expected caval congestionthe main features were paroxysmal dyspnoea and cyanosis. The patient was investigated using echocardiography, magneticresonance tomography and angiography.  相似文献   
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We have developed a complete excimer laser and fiber-optic angioplasty system and successfully opened completely occluded blood vessels in humans. We use the 308 nm XeCL excimer laser and fiber-optic delivery system that can be passed through a catheter or over a guidewire. In this article, we describe the knowledge essential for the interventionalist using the device: the method for generating 308 nm laser light, laser-tissue interaction, healing after laser injury, and how the rate of laser ablation is controlled. Our initial experience using the excimer laser in the superficial femoral artery has been excellent. (J of Interv Cardiology; 1988;1:1)  相似文献   
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Fourteen triploid spontaneous abortuses were studied cytogenetically by sequential Q and C banding and the marker chromosomes were compared with those of the parents. The abortuses comprised all triploid cases in a series of 288 consecutive abortuses of the first 16 weeks of pregnancy occurring in one hospital. In 12 of the triploids the origin of the extra haploid set was conclusively determined, revealing six cases of dispermy, five failures in the first maternal and one failure in the first paternal meiotic division. The results were combined with those of five other studies comprising a total of 48 informative cases. Non-reduction in the second meiotic division seems to be of little or no significance in the origin of human triploidy. Dispermy is the predominant source, accounting for 40--50% of the triploid spontaneous abortuses. Non-reduction in the first meiotic division of the father seems to be the second-most frequent source although in the present material the corresponding maternal non-reduction is much more common.  相似文献   
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