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121.
There is increasing proof that organ preservation by machine perfusion is able to limit ischemia/reperfusion injury in kidney transplantation. This study was designed to compare the efficiency in hypothermic organ preservation by machine perfusion or cold storage in an animal model of kidney autotransplantation.
Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion ( n  = 6) or cold storage ( n  = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5'-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation.
The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys.
The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage.  相似文献   
122.
The Id-proteins are a family of four related proteins implicated in the control of differentiation and cell-cycle progression. Down-regulation of Id-gene expression is essential for the differentiation of several cell types. In addition, deregulated Id2 activity inhibits the Rb tumor suppressor pathway and promotes the expression of vascular endothelial growth factor (VEGF). Several members of VEGF family could be involved in Kaposi's sarcoma (KS) development and progression. Lymphatic vascular endothelial hyaluronan receptor-1 (LYVE-1) is the first marker of lymphatic endothelial competence during development in the mature vasculature, and is also expressed on KS spindle cells. Rapamycin (RAPA), an immunosuppressive drug, has been shown to reverse KS growth and to reduce tumor angiogenesis. We evaluate, in transplantation-associated KS and in cultured KS-cells the RAPA effect on Id2 and on de novo lymphangiogenesis. Markers of lymphatic-endothelial-cells (VEGFR-3, LYVE-1) and Id2, expressed at low levels within the normal skin, were up-regulated in KS and returned to normal levels after RAPA introduction. The association between Id2 and lymphangiogenesis is suggested by co-localization of Id2, VEGFR-3 and LYVE-1. RAPA inhibition on Id2 expression was confirmed in vitro in KS-cells, both in basal conditions and upon stimulation with VEGF. In conclusion, our data would suggest a novel molecular mechanism for the antineoplastic effects of RAPA in posttransplant KS.  相似文献   
123.
RATIONALE: Tidal volume and plateau pressure limitation decreases mortality in acute respiratory distress syndrome. Computed tomography demonstrated a small, normally aerated compartment on the top of poorly aerated and nonaerated compartments that may be hyperinflated by tidal inflation. OBJECTIVES: We hypothesized that despite tidal volume and plateau pressure limitation, patients with a larger nonaerated compartment are exposed to tidal hyperinflation of the normally aerated compartment. MEASUREMENTS AND MAIN RESULTS: Pulmonary computed tomography at end-expiration and end-inspiration was obtained in 30 patients ventilated with a low tidal volume (6 ml/kg predicted body weight). Cluster analysis identified 20 patients in whom tidal inflation occurred largely in the normally aerated compartment (69.9 +/- 6.9%; "more protected"), and 10 patients in whom tidal inflation occurred largely within the hyperinflated compartments (63.0 +/- 12.7%; "less protected"). The nonaerated compartment was smaller and the normally aerated compartment was larger in the more protected patients than in the less protected patients (p = 0.01). Pulmonary cytokines were lower in the more protected patients than in the less protected patients (p < 0.05). Ventilator-free days were 7 +/- 8 and 1 +/- 2 d in the more protected and less protected patients, respectively (p = 0.01). Plateau pressure ranged between 25 and 26 cm H(2)O in the more protected patients and between 28 and 30 cm H(2)O in the less protected patients (p = 0.006). CONCLUSIONS: Limiting tidal volume to 6 ml/kg predicted body weight and plateau pressure to 30 cm H(2)O may not be sufficient in patients characterized by a larger nonaerated compartment.  相似文献   
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The present work aims at the application of several methods to explain differences in the physical interaction of some aryl propionic acid derivatives (ibuprofen [IBP], ketoprofen [KET], flurbiprofen [FLU], naproxen [NAP], fenbufen [FEN]) with poly(vinylpyrrolidone) (PVP) K30, stored together at 298 ± 0.5 K and 22% RH. X-ray powder diffractometry and 13C-solid state NMR demonstrated that IBP was able to strongly interact with the polymer, while weak interaction was observed for KET, FLU, NAP, and the least for FEN. The interaction of comelted drug and PVP was studied by differential scanning calorimetry by applying the Gordon–Taylor equation, which revealed that small molar drug volumes may favour the drug diffusion through the PVP amorphous chains increasing the polymer free volume and decreasing the mixture Tg. The molecular docking study revealed that intermolecular energy is mainly due to the contribution of van der Waals energy component, causing the differences among the drugs, and is related to the drug–PVP surface contact area in the complex formed. Solid-state kinetic study demonstrated that IBP molecules are involved in a three-dimensional diffusion mechanism within the polymer favoured by its low molar volume that reduces molecular hindrance, and by the weakness of its crystal lattice, which facilitates crystallinity loss and stabilisation of the amorphous phase. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4216–4228, 2009  相似文献   
126.
Preliminary data suggest that repetitive transcranial magnetic stimulation (rTMS) of the brain may produce a modest slowing of disease progression in amyotrophic lateral sclerosis (ALS). The present study was designed to test the hypothesis that rTMS given as continuous theta burst stimulation (cTBS), repeated monthly for one year, would affect ALS progression. We performed a double blind, placebo-controlled trial. Twenty patients with ALS were randomly allocated to blinded real or placebo stimulation. cTBS of the motor cortex was performed for five consecutive days every month for one year. Primary outcome was the rate of decline as evaluated with the revised ALS functional rating scale (ALSFRS-R). Treatment was well tolerated. There was no significant difference in the ALSFRS-R score deterioration between patients treated with real or placebo stimulation. ALSFRS-R mean scores declined from 32.0 (SD 7.1) at study entry to 23.1 (SD 6.3) at 12 months in patients receiving real cTBS and from 31.3 (SD 6.9) to 21.2 (SD 6.0) in those receiving placebo stimulation. Although cTBS proved a safe procedure, on the basis of the present findings a larger randomized confirmatory trial seems unjustified in ALS patients, at least in advanced stage of the disease.  相似文献   
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128.
OBJECTIVE: We evaluated the potential benefit of continuous positive airway pressure (CPAP) to prevent postoperative pulmonary complications (PPCs), atelectasis, pneumonia, and intubation in patients undergoing major abdominal surgery. SUMMARY BACKGROUND DATA: PPCs are common during the postoperative period and may be associated with a high morbidity rate. Efficacy of CPAP to prevent PPCs occurrence is controversial. METHODS: Medical literature databases were searched for randomized controlled trials examining the use of CPAP versus standard therapy in patients undergoing abdominal surgery. The meta-analysis estimated the pooled risk ratio and the number needed to treat to benefit (NNTB) for PPCs, atelectasis, and pneumonia. RESULTS: The meta-analysis was carried out over 9 randomized controlled trials. Overall, CPAP significantly reduced the risk of (1) PPCs (risk ratio, 0.66; 95% confidence interval [CI], 0.52-0.85) with a corresponding NNTB of 14.2 (95% CI, 9.9-32.4); (2) atelectasis (risk ratio, 0.75; 95% CI, 0.58-0.97; NNTB, 7.3; 95% CI, 4.4-64.5); (3) pneumonia (risk ratio, 0.33; 95% CI, 0.14-0.75; NNTB, 18.3; 95% CI, 14.4-48.8). In all cases the variation in risk ratio attributable to heterogeneity was negligible, although there was some evidence of publication bias. CONCLUSIONS: This systematic review suggests that CPAP decreases the risk of PPCs, atelectasis, and pneumonia and supports its clinical use in patients undergoing abdominal surgery.  相似文献   
129.
Pyrethroids are a class of insecticides involved in different neurological disorders. They cross the blood-brain barrier and exert their effect on dopaminergic system, contributing to the burden of oxidative stress in Parkinson's disease through several pathways. The aim of the present study was to evaluate the effect of neonatal exposition to permethrin and cypermethrin (1/10 of DL(50)) in rats from the eighth to the fifteenth day of life. Open-field studies showed increased spontaneous locomotor activity in the groups treated with permethrin and the one treated with cypermethrin, while a higher number of center entries and time spent in the center was observed for the cypermethrin-treated group. Lower dopamine and higher homovanillic acid levels were measured in the striatum from both treated groups. A reduction of blood glutathione peroxidase content was measured, while no change in blood superoxide dismutase was observed. Carbonyl group formation increased in striatum, but not in erythrocytes. Lipid peroxidation occurred in erythrocytes, but not in striatum. No changes in fluidity at different depths of plasma membrane were measured in striatum or erythrocytes. The activation of monocyte NADPH oxidase by phorbol esters (PMA) shows that superoxide anion production was reduced in the pyrethroid-treated groups compared to the control group. Our studies suggest that neonatal exposition to permethrin or cypermethrin induces long-lasting effects after developmental exposure giving changes in open-field behaviors, striatal monoamine level, and increased oxidative stress. Although the action of pyrethroids on various target cells is different, a preferential interaction with the extracellular side of plasma membrane proteins can be observed.  相似文献   
130.
International Journal of Clinical Pharmacy - Effective communication strategies in health care help to enhance patient empowerment and improve clinical outcomes. Adapt the original Communication...  相似文献   
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