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991.
Purpose To study the ultrasound (US) findings and clinical significance of transient small bowel intussusceptions (TSBI) in adults and children. Methods Clinical records and US findings of 108 consecutive patients of intestinal intussusception diagnosed on US between August 1995 and August 2004 were reviewed. In all cases, the length, diameter, wall thickness and color Doppler study of the bowel segment involved in intussusception were evaluated. Subsequent follow-up scans were performed at 30 min, 3 days and 2 weeks. Patients were clinically followed up for 6 months. Results Forty-one patients were diagnosed as TSBI. Thirty-six intussusceptions were incidentally detected during US performed for some unrelated disease or vague abdominal symptom. Five patients presented with signs of obstruction at the time of the initial US diagnosis; however, the intussusceptions resolved without any treatment and were not detected on follow-up scans. Sixty-seven symptomatic patients required surgical intervention. Conclusion Incidentally detected, small bowel intussusceptions without an identifiable pathological lead point, with a normal wall thickness, a length of less than 3.5 cm, normal nondilated proximal bowel and normal vascularity on color Doppler reduce spontaneously and are of no clinical significance.  相似文献   
992.
993.
There is little information on the surgical management of Takayasu's arteritis in children and adolescents. Information on 30 patients aged between eight and 17 years was culled from a prospectively maintained database on the Vascular Service of the University of KwaZulu-Natal, Durban, South Africa. Twenty-one patients had involvement of the descending aorta; in 19, this was confined to the aorta (type 2 disease). One had associated arch disease (type 3) and one had associated cardiac disease (type 4). One patient had isolated axillary artery occlusion (type 5). Eight patients had disease confined to the aortic arch (type 1), 22 had occlusive disease and eight were aneurysmal. All patients had operative repairs undertaken. There were no peri-operative deaths in the group who had cerebrovascular reconstruction, and one death (4.5%) in those who had descending aortic replacement. Patients were followed up for between one month and 11 years. Hypertension was improved or cured in 10 of 12 patients. Two died during this period and another five patients (20%) required further surgery for stenosis (three patients) or anastomotic aneurysms (two). CONCLUSION: Bypass surgery yields satisfactory results in this age group in terms of peri-operative and medium-term mortality and morbidity.  相似文献   
994.
Bradykinin causes arterial relaxation and hyperpolarization, which is mediated by a transferable endothelium-derived hyperpolarizing factor (EDHF). In coronary arteries, epoxyeicosatrienoic acids (EETs) are involved in the EDHF response. However, the role of EETs as transferable mediators of EDHF-dependent relaxation remains poorly defined. Two small bovine coronary arteries were cannulated and perfused in tandem in the presence of the nitric oxide synthase inhibitor, nitro-L-arginine (30 micromol/L), and the cyclooxygenase inhibitor, indomethacin (10 micromol/L). Luminal perfusate from donor arteries with intact endothelium perfused endothelium-denuded detector arteries. Detector arteries were constricted with U46619 and diameters were monitored. Bradykinin (10 nmol/L) added to detector arteries did not induce dilation (5+/-2%), whereas bradykinin addition to donor arteries dilated detector arteries by 26.5+/-7% (P<0.05). These dilations were blocked by donor artery endothelium removal and detector artery treatment with the EET-selective antagonist, 14,15-epoxyeicosa-5(Z)-monoenoic acid (14,15-EEZE; 10 micromol/L, -5+/-6%) but not 14,15-EEZE treatment of donor arteries (20+/-5%). 14,15-EET (0.1 to 10 micromol/L) added to detector arteries induced maximal dilations of 82+/-5% that were inhibited 50% by detector artery treatment with 14,15-EEZE (32+/-12%) but not donor artery treatment with 14,15-EEZE. Liquid chromatography-electrospray ionization mass spectrometry analysis verified the presence of 14,15-EET in the perfusate from an endothelium-intact but not denuded artery. These results show that bradykinin stimulates donor artery 14,15-EET release that dilates detector arteries. 14,15-EEZE blocked the donor artery, endothelium-dependent, bradykinin-induced relaxations, and attenuated relaxations to 14,15-EET. These results suggest that EETs are transferable EDHFs in coronary arteries.  相似文献   
995.
ObjectiveTo investigate the effect of bidi smoking on erythrocyte antioxidant status, membrane fluidity.Design and methodsThirty experimental and control subjects (mean age 35 ± 5) were selected for the study. Experimental subjects smoke 22 ± 4 bidis per day for 8–10 years.ResultsIncrease in plasma total cholesterol, LDL-cholesterol, triglycerides, lipid peroxidation, protein carbonyls with a decrease in HDL-cholesterol, thiol groups as well as increased erythrocyte catalase (CAT), superoxide dismutase (SOD), decreased glutathione peroxidase (GPx) activity and reduced glutathione (GSH) content was observed in bidi smokers. Increase in the erythrocyte membrane lipid peroxidation, cholesterol phospholipids (C/P) ratio as well as decrease in protein and Na+/K+-ATPase activity was observed. Increase in nitrite/nitrate (NOx) levels of plasma, red cell lysate was positively correlated with C/P ratio (r = 0.614) and Na+/K+-ATPase (r = 0.435) in bidi smokers.ConclusionsBidi smoke alters antioxidant status, red cell membrane fluidity and increases atherogenicity.  相似文献   
996.
Magnetic resonance imaging of cells labeled with superparamagnetic iron oxide (SPIO) could be a valuable tool for tracking transplanted cells in living organisms. Human bone marrow‐derived mesenchymal stem cells (hBMMSC) were labeled with a novel polyvinyl pyrrolidone (PVP)‐coated SPIO. Prussian blue staining and electron microscopy revealed that almost all of the cells were efficiently labeled with PVP–SPIO nanoparticles. There were no signs of cytotoxicity, even at concentrations of up to 1600 µg Fe/ml of the nanoparticles, and the labeled cells were successfully visualized by in vitro cellular MRI. In addition, there was no significant alteration of the phenotype or the adipo/osteo/chondrogenic differentiation potential of the cells. This was in contrast to Feridex IV labeling that led to the inhibition of hBMMSC chondrogenesis. Following intramuscular injection in a rabbit hind limb ischemia model, the intercellular migration of the labeled cells toward the ablated site was clearly tracked through in vivo MRI. The localization of the transplanted cells observed by MRI correlated well with postmortem histological studies. These results demonstrate that the novel PVP–SPIO nanoparticles appear to be efficient MR contrast agents and may enable non‐invasive in vivo tracking of stem cells in experimental and clinical settings during cell therapy. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
997.
Background: Breast cancer remains a major cause of morbidity and mortality world-wide. While aminoglutethimide, a first-generation aromatase inhibitor, has equivalent efficacy to first-line tamoxifen in the palliative treatment of metastatic breast cancer, its toxicity profile has relegated this drug to a second- or third-line agent in this setting. Recently, several aromatase inhibitors have been released onto the market while others are in phase II and III clinical trials Aim: To review the role of the new aromatase inhibitors in the management of metastatic breast cancer Methods: Current literature, abstracts from meetings and information from pharmaceutical manufacturers have been summarized Content: A review of the clinical pharmacology of the new aromatase inhibitors has been provided in addition to a synopsis of phase III clinical studies Conclusion: The newer aromatase inhibitors have several advantages compared to aminoglutethimide and are a useful addition to the armamentarium of therapies employed in the palliative management of advanced breast cancer  相似文献   
998.
Reddy PJ  Aksoy MO  Yang Y  Li XX  Ji R  Kelsen SG 《COPD》2008,5(1):5-11
The CXC chemokines, IP-10/CXCL10 and IL-8/CXCL8, play a role in obstructive lung disease by attracting Th1/Tc1 lymphocytes and neutrophils, respectively. Inhaled corticosteroids (ICS) and long acting beta 2-agonists (LABA) are widely used. However, their effect(s) on the release of IP-10 and IL-8 by airway epithelial cells are poorly understood. This study examined the effects of fluticasone, salmeterol, and agents which raise intracellular cAMP (cilomilast and db-cAMP) on the expression of IP-10 and IL-8 protein and mRNA. Studies were performed in cultured human airway epithelial cells during cytokine-stimulated IP-10 and IL-8 release. Cytokine treatment (TNF-alpha, IL-1beta and IFN-gamma) increased IP-10 and IL-8 protein and mRNA levels. Fluticasone (0.1 nM to 1 microM) increased IP-10 but reduced IL-8 protein release without changing IP-10 mRNA levels assessed by real time RT-PCR. The combination of salmeterol (1 micro M) and cilomilast (1-10 mu M) reduced IP-10 but had no effect on IL-8 protein. Salmeterol alone (1 micro M) and db-cAMP alone (1 mM) antagonised the effects of fluticasone on IP-10 but not IL-8 protein. In human airway epithelial cells, inhibition by salmeterol of fluticasone-enhanced IP-10 release may be an important therapeutic effect of the LABA/ICS combination not present when the two drugs are used separately.  相似文献   
999.
Abstract: We present a case of diarrhea secondary to biopsy‐proven adenovirus (ADV) infection after autologous peripheral hematopoietic stem cell transplant for multiple myeloma. The patient had a negative plasma polymerase chain reaction for ADV and a dramatic clinical response to low‐dose cidofovir. To our knowledge, this is the first report in an adult hematopoietic stem cell recipient of the use of low‐dose cidofovir to treat proven ADV gastrointestinal infection.  相似文献   
1000.

BACKGROUND

Diabetes mellitus is an independent risk factor for cardiovascular disease and is also associated with increased susceptibility to cardiovascular complications. It has been suggested that alterations in glucose metabolism and glucose flux via the aldose reductase pathway make the diabetic heart more sensitive to ischemic-reperfusion injury. Previous studies have found sulindac to have inhibitory and anti-inflammatory effects on aldose reductase. The use of aldose reductase inhibitors for the protection of ischemic myocardium is still in an exploratory state.

OBJECTIVES

To evaluate the therapeutic potential of sulindac in an in vivo rat model of acute ischemia (30 min) and reperfusion (4 h) in diabetic and nondiabetic rats.

METHODS

Diabetes was induced in rats by administering streptozotocin (45 mg/kg, intravenously). Myocardial infarction was induced by occlusion of the left anterior descending coronary artery for 30 min followed by 4 h of reperfusion. Infarct size was measured using the staining agent 2,3,5-triphenyltetrazolium chloride. A lead II electrocardiogram was monitored at various intervals throughout the experiment. Sorbitol dehydrogenase levels in heart tissue, as well as lipid peroxide levels in serum and heart tissue, were estimated spectrophotometrically.

RESULTS

Infarct size was increased in diabetic rats in comparison with normal rats. Pretreatment with sulindac significantly reduced infarct size, lipid peroxidation and sorbitol dehydrogenase levels in both diabetic and nondiabetic rats. The degree of cardioprotection was greater in diabetic rats than in nondiabetic rats.

CONCLUSIONS

The present study indicates that the observed cardioprotection provided by sulindac in terms of reducing infarct size in normal rats may be due to its combined antioxidant and anti-inflammatory activities. The inhibition of aldose reductase may be responsible for the enhanced cardioprotection observed in diabetic rats treated with sulindac.  相似文献   
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