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Proteases as well as alterations in intracellular calcium have important roles in hepatic preservation-reperfusion injury, and increased calpain activity recently has been demonstrated in liver allografts. Experiments were designed to evaluate (i) hepatic cytosolic calpain activity during different periods of cold ischemia (CI), rewarming, or reperfusion, and (ii) effects of inhibition of calpain on liver graft function using the isolated perfused rat liver and arterialized orthotopic liver transplantation models. Calpain activity was assayed using the fluorogenic substrate Suc-Leu-Leu-Val-Tyr-7-amino-4-methyl coumarin (AMC) and expressed as mean ± SD pmol AMC released/min per mg of cytosolic protein. Calpain activity rose significantly after 24 hr of CI in University of Wisconsin solution and further increased with longer preservation. Activity also increased within 30 min of rewarming, peaking at 120 min. Increased durations of CI preceding rewarming resulted in significantly higher activity (P < 0.01). Calpain activity increased rapidly upon reperfusion and was significantly enhanced by previous CI (P < 0.01). Calpain inhibition with Cbz-Val-Phe methyl ester significantly decreased aspartate aminotransferase released in the isolated perfused rat liver perfusate (P < 0.05). Duration of survival after orthotopic liver transplantation using livers cold-preserved for 40 hr was also significantly increased (P < 0.05) with calpain inhibitor. In conclusion, calpain proteases are activated during each phase of transplantation and are likely to play an important role in the mechanisms of preservation-reperfusion injury.  相似文献   
84.
STUDY OBJECTIVE: Inhaled corticosteroids (ICs) improve airflow and decrease symptoms in patients with chronic asthma. We examined whether high-dose inhaled flunisolide would have similar benefits after an emergency department visit for acute asthma. METHODS: Over a 16-month period at one inner-city ED, we documented 551 eligible patients (acute asthma; age 18 to 50 years; no ICs in past week; no oral corticosteroids in past month; and peak expiratory flow rate [PEFR] <70% of predicted value after first beta-agonist treatment); 104 patients agreed to participate. At ED discharge, all patients were given prednisone 40 mg/d for 5 days and inhaled beta-agonists as needed and were randomly assigned to receive high-dose inhaled flunisolide 2 mg/d (n=51) or placebo (n=53). Patients were telephoned daily and asked to return for PEFR measurement at 3, 7, 12, 21, and 24 days. RESULTS: Despite precautions, 28% (16 receiving flunisolide and 13 receiving placebo) of patients were completely lost to follow-up, 2 patients had only one follow-up (day 3), 2 patients receiving flunisolide withdrew because of medication-related bronchospasm, and 4 patients in each group experienced relapse. Among the 63 remaining patients, we found no difference between flunisolide and placebo at day 24 follow-up in percent predicted PEFR (87% versus 83% on day 24, P =.36; difference 4%, 95% confidence interval [CI] -5% to 13%). Nocturnal wheezing and nocturnal albuterol inhaler use was higher among patients receiving flunisolide than those receiving placebo on day 24 (48% versus 18% for nocturnal wheezing, P =.01; mean difference 30%, 95% CI 11% to 49%; 3.8 versus 1.4 nocturnal albuterol puffs, P =.03; mean difference 2.4 puffs, (95% CI 0.2 to 4). Levels of dyspnea, cough, and overall well-being were similar between the flunisolide and placebo groups. CONCLUSION: Addition of high-dose inhaled flunisolide to standard therapy does not benefit inner-city patients with acute asthma in the first 24 days after ED discharge. Airway inflammation during acute asthma may require higher doses or more potent anti-inflammatory agents.  相似文献   
85.
Comparison of two clinical scales for causality assessment in hepatotoxicity   总被引:15,自引:0,他引:15  
This study was performed to compare the assessments of drug-induced liver injury obtained with 2 methods, the Council for International Organizations of Medical Sciences (CIOMS) scale and the recently validated Maria & Victorino (M&V) clinical scale, in cases submitted to a registry of hepatotoxicity. A total of 215 cases of hepatotoxicity reported with a structured reporting form were evaluated by 3 independent experts. Because of the use of multiple drugs, 228 ratings were generated. The probability of the diagnosis was classified as definitive, probable, possible, unlikely, or excluded, and evaluated for consistency with a weighted kappa statistical test. Absolute agreement between the 2 scales was observed in 42 cases (18%, weighted kappa 0.28) with disagreement of 1 level in 108 cases (47%), and of 2 levels in 70 cases (31%). The best correlation between the 2 scales was obtained for drug-induced liver injury involving a suggested immunoallergic mechanism: the disagreement was 1 level or less in 72% of the cases (34 of 48), compared with 60% of the cases (85 of 141) that involved a presumed idiosyncratic metabolic mechanism. The lowest agreement (6%) was observed in cases with evidence of cholestasis. No agreement was found in cases of fulminant hepatitis or death. The CIOMS scale showed better discriminative power and produced assessments closer to those of specialists. The performance of the M&V scale was poor in reactions with long latency periods (i.e., amoxycillin/clavulanic acid), evolution to chronicity after withdrawal (cholestatic pattern), or death.  相似文献   
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87.
Effects of androgen on sexual behavior in hypogonadal men.   总被引:5,自引:0,他引:5  
Despite the widespread use of androgen in the treatment of hypogonadal men, its efficacy in restoring sexual behavior to hypogonadal patients has not been established in appropriately controlled behavioral studies. Accordingly, testosterone enanthate or vehicle was injected once every 4 weeks im in a double blind experiment. The subjects were six adult males, aged 32-65 yr, two with gonadal failure and four with secondary hypogonadism. Two doses of testosterone (100 and 400 mg) were administered for approximately 5 months, with the treatments varied at random within and among subjects. Details of sexual activity and experience were followed by the use of daily logs. Frequencies of erections, including nocturnal erections and coitus, showed significant dose-related responses to androgen treatment which closely followed the fluctuations in the circulating testosterone level. As indicated by the Profile of Mood States test, behavioral responses did not appear to be mediated by changes in mood. We concluded that the stimulatory effects of testosterone on sexual activity are rapid, reliable, and not due to a placebo effect. To maintain plasma testosterone and adequate sexual function within normal levels, even high doses of testosterone enanthate should be given no less frequency than once every 3 weeks.  相似文献   
88.
Thus far, there has been a paucity of studies that have assessed the value of the different gastroesophageal reflux disease (GERD) symptom characteristics in identifying patients with long-segment Barrett's esophagus versus those with short-segment Barrett's esophagus. To determine if any of the symptom characteristics of GERD correlates with long-segment Barrett's esophagus versus short-segment Barrett's esophagus. Patients seen in our Barrett's clinic were prospectively approached and recruited into the study. All patients underwent an endoscopy, validated GERD symptoms questionnaire and a personal interview. Of the 88 Barrett's esophagus patients enrolled into the study, 47 had short-segment Barrett's esophagus and 41 long-segment Barrett's esophagus. Patients with short-segment Barrett's esophagus reported significantly more daily heartburn symptoms (84.1%) than patients with long-segment Barrett's esophagus (63.2%, P = 0.02). There was a significant difference in reports of severe to very severe dysphagia in patients with long-segment Barrett's esophagus versus those with short-segment Barrett's esophagus (76.9%vs. 38.1%, P = 0.02). Longer duration in years of chest pain was the only symptom characteristic of gastroesophageal reflux disease associated with longer lengths of Barrett's mucosa. Reports of severe or very severe dysphagia were more common in long-segment Barrett's esophagus patients. Only longer duration of chest pain was correlated with longer lengths of Barrett's esophagus.  相似文献   
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90.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited myocardial disease that predominantly affects the right ventricle and is associated with ventricular arrhythmias that may lead to sudden cardiac death. Mutations within at least seven separate genes have been identified to cause ARVC, however a genetic culprit remains elusive in approximately 50% of cases. Although negative genetic testing may be secondary to pathogenic mutations within undiscovered genes, an alternative explanation may be the presence of large deletions or duplications involving known genes. These large copy number variants may not be detected with standard clinical genetic testing which is presently limited to direct DNA sequencing. We describe two cases of ARVC possessing large deletions involving plakophilin‐2 (PKP2) identified with microarray analysis and/or multiplex ligation‐dependent probe amplification (MLPA) that would have been classified as genotype negative with standard clinical genetic testing. A deletion of the entire coding region of PKP2 excluding exon 1 was identified in patient 1 and his son. In patient 2, MLPA analysis of PKP2 revealed deletion of the entire gene with subsequent microarray analysis demonstrating a de novo 7.9 Mb deletion of chromosome 12p12.1p11.1. These findings support screening for large copy number variants in clinically suspected ARVC cases without clear disease causing mutations following initial sequencing analysis.  相似文献   
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