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61.
The authors performed a study of intraocular pressure-dependent changes in optic disc cupping in 17 adults with chronic open-angle glaucoma. Analyses with the Rodenstock Optic Nerve Head Analyzer were performed at baseline low intraocular pressure during therapy, after elevation of intraocular pressure (from therapeutic failure or noncompliance), and after reduction of intraocular pressure with successful therapy. Optic disc cupping increased significantly upon short-term increase of intraocular pressure from baseline of 20.4 +/- 2.5 mmHg to 31.1 +/- 5.9 mmHg. Optic disc cupping reverted to baseline after persistent intraocular pressure reduction to 19.3 +/- 4.8 mmHg. These data demonstrate intraocular pressure-dependent dynamic changes of optic disc cupping in patients with demonstrable glaucomatous optic nerve damage. They underscore the detrimental effect of elevated intraocular pressure and the beneficial effect of intraocular pressure reduction on optic disc cup changes.  相似文献   
62.
The relation between smoking and risk of asthma has been well-examined; however little attention has been paid to the correlation between smoking and asthma symptoms. The aims of this study were to examine respiratory symptoms in asthmatics with a highly prevalent use of inhaled corticosteroid (ICS) and to assess the effects of smoking and its cessation. A cross-sectional study of pulmonologist-based 3197 asthmatics (men 45.2%, ages 20-97) was performed using a questionnaire about smoking habits, the incidence and frequency of symptoms (sputum, cough and wheezing, night symptoms, and shortness of breath), physical activity interference, and medication. Although 81.4% of the patients used ICS according to the international guideline, 14.9% had activity interference, and daily symptoms remained in 43.3%. At the time of the questionnaire, 21.6% were current and 25.1% were ex-smokers. In multiple logistic regression analysis, the factors of significance (p < 0.0001) were (1) smoking; for all four symptoms, (2) age and duration of asthma; for shortness of breath. Current smokers were at a risk of sputum (age-adjusted odds ratio 2.32 [95% confidence interval 1.73-3.11]; 2.09 [1.57-2.79]), of cough and wheezing (2.38 [1.81-3.14]; 1.78 [1.35-2.36]), of night symptoms (1.95 [1.41-2.60]; 1.47 [1.09-1.98]), and of shortness of breath (1.70 [1.26-2.28]; 1.30 [0.97-1.75]) in men and women, respectively. These ratios in ex-smokers decreased to the level similar to nonsmokers. Although 81.4% of asthmatic patients used ICS, 43.3% complained of daily respiratory symptoms, especially sputum. It is suggested that the effects of ICS on asthma symptoms may be interfered with by smoking and therefore more emphasis should be placed on cessation of smoking.  相似文献   
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Leukocyte chemoattraction by 1,2-diacylglycerol.   总被引:3,自引:0,他引:3  
Previous reports have demonstrated the hydrolysis of inositol phospholipids in polymorphonuclear leukocytes (PMN) in response to chemoattractants and in lymphocytes in response to the mitogen phytohemagglutinin. We investigated the role of 1,2-diacylglycerol, one of the products of receptor-linked phosphatidylinositol hydrolysis, in mediating the migratory response of leukocytes. In an under-agarose migration system, we found 1,2-dioctanoylglycerol to be a strong chemoattractant for human PMN, 6C3HED (a mouse thymic lymphoma), and Jurkat (a human T-cell leukemia). By using a modified Boyden chamber assay, the migratory response of PMN to 1,2-dioctanoylglycerol was determined to be primarily chemotactic. Analysis of structural analogs indicated that both the position and number of acyl chains are important in determining chemoattractant activity. These studies demonstrate that exogenous 1,2-diacylglycerol can stimulate the directed migration of leukocytes. They further suggest that the formation of 1,2-diacylglycerol following receptor-mediated stimulation may represent a common step in the migratory responses of myeloid and lymphoid cells.  相似文献   
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Cancer patients frequently have anemia or an altered coagulation state that may affect their risk stratification for perioperative cardiac events. We performed this study to investigate the incidence of perioperative cardiac events in cancer patients who had abnormal stress myocardial perfusion imaging (MPI) results versus cancer patients with normal MPI results. METHODS: We included 394 consecutive cancer patients with normal (n = 201) or abnormal (n = 193) results on MPI studies performed for preoperative risk stratification. MPI was performed within 6 mo before each patient's scheduled operation. All the patients had surgical procedures requiring general anesthesia, except for 18 who had endoscopic or colonoscopic procedures. We retrospectively reviewed their data for the incidence of major cardiac events intraoperatively and for 1 mo postoperatively. We collected data on their cancer type, risk factors for coronary artery disease, MPI findings, risk of operation, and intraoperative or postoperative major cardiac events, which included death, myocardial infarction (MI), and congestive heart failure (CHF). RESULTS: The patients with abnormal MPI results included 97 with ischemia, 80 with scarring, and 16 with mixed scarring and ischemia. The mean left ventricular ejection fraction and end-diastolic volume were 63.8% +/- 9.8% and 82.0 +/- 53.5 mL in the normal MPI group versus 52.1% +/- 13.1% and 118.1 +/- 53.4 mL in the abnormal-MPI group (P < 0.001). There were 9 major intraoperative or postoperative cardiac events (4.7%) in the patients with abnormal MPI results and none in the patients with normal MPI results (P = 0.001). These major events consisted of 3 deaths, 2 acute MIs, 1 non-Q-wave MI, and 3 cases of CHF. Four of these patients had only scarring on their MPI studies, 3 had ischemia, and 2 had scarring and ischemia. CONCLUSION: Normal MPI results have a high negative predictive value for perioperative cardiac events in cancer patients. Abnormal MPI results, whether demonstrating scarring or ischemia, should prompt appropriate perioperative management in patients with cancer to minimize major cardiac events.  相似文献   
68.
The azygos anterior cerebral artery, a rare anomaly in the circle of Willis in which only a single vessel supplies the medial aspects of both anterior cerebral hemispheres, is closely associated with saccular aneurysms. We present three cases of azygos anterior cerebral artery aneurysms among the 781 cerebral aneurysms surgically treated at our institution in an 11-year period. These three cases all involved elderly women who presented with subarachnoid hemorrhage. Conventional cerebral angiography and CT angiography revealed small saccular aneurysms at the distal ends of the azygos anterior cerebral arteries. These aneurysms were clipped successfully using a bifrontal interhemispheric approach. Hence, the pathogenesis of these particular aneurysms relating to hemodynamic change, associated anomalies, and surgical pitfalls is discussed with review of literature.  相似文献   
69.
We report here our 10-year experience of a biopsy performed at day 14 after transplantation in 304 patients with stable graft function. The factors that may have influenced subclinical rejection were analyzed according to histology. The incidence of subclinical rejection was 13.2%. Addition of mycophenolate mofetile (MMF) as a primary immunosuppressant significantly decreased the incidence of subclinical rejection compared with patients without such treatment (odds ratio, 0.23; p < 0.05). On the other hand, HLA-DR antigen mismatch (odds ratio, 2.39) and unrelated donor (odds ratio, 2.10) were also significantly associated with decreased subclinical rejection (p < 0.05). The incidence of acute rejection in patients with normal findings was lower than in those with borderline changes or subclinical rejection (0.23 +/- 0.05 vs. 0.48 +/- 0.07 and 0.60 +/- 0.11, respectively; p < 0.05). The graft survival rates in patients with subclinical rejection were lower than in patients with normal or borderline changes at 1 (88.4% vs. 97.9% and 99.1%; p < 0.05), 5 (77.8% vs. 96.2% and 95.9%; p < 0.05) and 10 (62.3% vs. 96.2% and 93.7%; p < 0.05) years. Thus, a protocol biopsy performed on day 14 after transplantation is useful for predicting graft survival. Triple therapy including MMF, related donor and HLA-DR antigen match are important factors for reducing subclinical rejection in living-donor renal transplantation.  相似文献   
70.
OBJECTIVE: Behavioral disturbances in dementia are extremely prominent and distressful, and often result in serious physical, social, and economic consequences. The authors compared the efficacy and tolerability of risperidone and haloperidol in the treatment of behavioral and psychological symptoms of dementia (BPSD) in institutionalized elderly Korean patients with Alzheimer disease, vascular dementia, or mixed dementia. METHODS: This was an 18-week double-blind, crossover study involving 120 patients who were randomly assigned to receive flexible doses (0.5-1.5 mg/day) of risperidone or haloperidol. BPSD were assessed using the Korean version of the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD-K), the Korean version of the Cohen-Mansfield Agitation Inventory (CMAI-K), and the Clinical Global Impression of Change scale (CGI-C). Safety and tolerability assessments included the Extrapyramidal Symptom Rating Scale and the incidence of adverse events. RESULTS: Both risperidone and haloperidol were efficacious in alleviating BPSD. However, when receiving risperidone, patients showed significantly greater improvement than when receiving haloperidol in the total and subscale scores of the BEHAVE-AD-K, the total and subscale scores of the CMAI-K, and the scores on the CGI-C scale. Also, risperidone had an additional benefit on aggressiveness and anxieties/phobias. The risk of antipsychotic-induced parkinsonism throughout this study was significantly lower with risperidone than with haloperidol. CONCLUSION: Risperidone had a favorable efficacy and tolerability profile compared with haloperidol in the treatment of BPSD in this patient population.  相似文献   
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