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71.
72.
We recently concluded that exposure to solvent-contaminated drinking water was an unlikely explanation for observed excesses of adverse pregnancy outcomes during 1980–1981 in the Los Paseos neighborhood of Santa Clara County, California, because these excesses were not observed in an adjacent exposed area. The validity of this conclusion depends on the assumption that the two areas had comparable exposure. Using quantitative methods to model movement of the solvent leak plume and water flow within the distribution system, we estimated that women with adverse outcomes were no more likely to have received contaminated water than women with normal live births. These results strengthen the conclusion that exposures to water from the contaminated well were not responsible for the excess of adverse outcomes observed in the Los Paseos area.  相似文献   
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A Schmorl’s node is a common incidental finding encountered during radiologic imaging. Despite the vertebral body being a common site of metastatic disease, a lytic lesion adjacent to an endplate with typical imaging features can often confidently be called a Schmorl’s node. This is a case report of a patient with a single well-defined FDG-avid papillary thyroid carcinoma metastasis to the spine that had imaging findings characteristic of a Schmorl’s node on CT and MRI. This case is important to consider as it demonstrates that the imaging characteristics of metastatic disease and Schmorl’s nodes can overlap.  相似文献   
75.
Aim   To examine whether Rasch modeling would yield a unidimensional withdrawal sensitivity measure correlating with factors associated with successful smoking cessation.
Design   The psychometric Rasch modeling approach was applied to estimate an underlying latent construct (withdrawal sensitivity) in retrospective responses from 1644 smokers who reported quitting for 3 or more months at least once.
Setting   Web-based, passcode-controlled self-administered computerized questionnaire.
Participants   Randomly selected convenience sample of 1644 adult members of an e-mail invitation-only web panel drawn from consumer databases.
Measurements   Lifetime Tobacco Use Questionnaire, assessing tobacco use across the life-span, including demographics and respondent ratings of the severity of withdrawal symptoms experienced in respondents' first and most recent quit attempts lasting 3 or more months.
Findings   Rasch-modeled withdrawal sensitivity was generally unidimensional and was associated with longer periods of smoking cessation. One latent variable accounted for 74% of the variability in symptom scores. Rasch modeling with a single latent factor fitted withdrawal symptoms well, except for increased appetite, for which the fit was marginal. Demographic variables of education, gender and ethnicity were not related to changes in sensitivity. Correlates of greater withdrawal sensitivity in cessation attempts of at least 3 months included younger age at first quit attempt and indicators of tobacco dependence.
Conclusion   The relationship between tobacco dependence symptoms and Rasch-model withdrawal sensitivity defines further the relationship between sensitivity and dependence. The findings demonstrate the utility of modeling to create an individual-specific sensitivity measure as a tool for exploring the relationships among sensitivity, dependence and cessation.  相似文献   
76.
The epidemiology of hyperuricaemia and gout in Taiwan aborigines   总被引:4,自引:1,他引:4  
To determine the prevalence of hyperuricaemia, gout and gout-related factors in Central Taiwan Atayal aborigines, 342 subjects over 18 yr old were interviewed and examined. A questionnaire was designed to screen for signs and symptoms of gout and gout-related risk factors. Serum uric acid, triglyceride and creatinine were measured in all subjects. The prevalence of hyperuricaemia was 41.4% and that of gout 11.7% in aborigines. The uric acid level was 7.9+/-1.7 mg/dl in males and 5.7+/-1.5 in females, and differed significantly under age 70 yr (P < 0.001). Significantly increased triglyceride, creatinine and alcoholism was found in gouty patients compared with non-gouty patients. In 40 cases with gout, 54% had tophi and 35% of their first- degree relatives had gout. The high prevalence of hyperuricaemia and gout in Taiwan Atayal aborigines, a significant family predisposition, increased creatinine level and alcoholism suggest multiple factors affecting the hyperuricaemia.   相似文献   
77.
Two children are reported in whom intestinal pseudo-obstruction was the initial manifestation of systemic sclerosis. Gastrointestinal symptoms and skin changes resolved or improved in both children following treatment with prednisone and penicillamine (case 1) or methotrexate (case 2), although radiological changes of the gastrointestinal tract persisted at 3 and 2 yr of follow-up, respectively.   相似文献   
78.
OBJECTIVE--To evaluate a clinic set up specifically to assess patients with recent onset chest pain, particularly those presenting with a normal resting electrocardiogram. DESIGN--Retrospective review of case notes. SETTING--Cardiac department of a tertiary referral cardiothoracic centre. PATIENTS--250 consecutive patients with recent onset chest pain seen within 24 hours of general practitioner referral. OUTCOME MEASURES--Clinical diagnosis and management. RESULTS--40% of patients were seen within seven days of the onset of symptoms. Twenty seven per cent had non-cardiac symptoms and could be discharged while 60% were considered to have cardiac pain. Sixty six patients (26%) were admitted directly from the clinic and 48 of these underwent coronary angiography within three weeks. Seventy patients (28%) have so far undergone intervention (angioplasty or coronary artery surgery), 22 within one month of presentation. One hundred and nine patients (44%) presented with a normal resting electrocardiogram, 21 of whom were considered to have unstable angina. Forty one of these patients were investigated of whom 37 were found to have significant coronary disease and 26 have undergone intervention. CONCLUSIONS--This experience highlights the inadequacy of a routine electrocardiogram reporting service in patients with recent onset of chest pain. An alternative facility offering immediate and complete cardiac assessment produced patient benefit with early diagnosis and intervention. Investigation of these patients, however, accounted for 5% of cardiac catheterisation laboratory throughput; this was a significant additional and unscheduled workload.  相似文献   
79.
The radionuclide ventriculographic exercise response was evaluated in three patient populations representing alternative referent standards for cardiac normality: patients with normal coronary arteriograms, healthy volunteers, and uncatheterized patients with a low probability of coronary artery disease. Disease probability was determined by Bayesian analysis of age, sex, symptoms, and the results of cardiac fluoroscopy, exercise electrocardiography, or thallium scintigraphy. A wide range of ventriculographic responses was noted in the 62 catheterized normal patients; 21 (34%) had an abnormal ejection fraction response and 22 (35%) had an abnormal wall motion response. In contrast, the ejection fraction and wall motion responses were normal in the 9 volunteers. In 90 patients (18 catheterized and 72 uncatheterized) who had low disease probability (less than 1%), abnormal responses were rare; the ejection fraction response was abnormal in only 7% and the wall motion response was abnormal in 8%. Thus, these three populations are not equivalent referent standards of normality. Volunteers and patients with low disease probability provide too strict a standard, and their use can overestimate test specificity; catheterized normal patients, on the other hand, provide too lenient a standard, and their use can underestimate test specificity.  相似文献   
80.
BACKGROUND & AIMS: In patients with chronic hepatitis C (CHC), percutaneous needle liver biopsy examination establishes the severity of necroinflammatory activity and fibrosis, thus guiding treatment decisions. Optimal biopsy specimen size remains controversial. We sought to determine how varying lengths of biopsy specimens influence the grading and staging of CHC. METHODS: We used 100 liver biopsy specimens from patients with CHC. The slides were evaluated blindly using the METAVIR scoring system, after being covered with paper, so that only specific specimen lengths (5 mm, 10 mm, 15 mm, and > or =20 mm) were visible. In each case, the scores obtained with biopsies 5 mm, 10 mm, or 15 mm long were compared with the scores at 20 mm or greater by weighted kappa statistics (kappa of >.75 signified excellent agreement). A subset of specimens 20 mm or greater was selected for a blinded repeat scoring to assess intraobserver agreement. The kappa statistics for the designated features and lengths were compared using analysis of variance. RESULTS: In assessing the stage of fibrosis, the weighted kappa statistics for agreement with the 20-mm or greater score at 5 mm, 10 mm, and 15 mm were .75, .85, and .92, respectively. In assessing the histologic activity score, the corresponding figures were .73, .81, and .77, respectively. Average kappa statistic comparisons showed that intraobserver agreement was significantly better than agreement between the 20-mm or greater scores and those at shorter lengths; the 5-mm kappa scores were significantly lower than the others; and there was no significant difference between the 10-mm and 15-mm kappa scores. CONCLUSIONS: Liver biopsy specimens measuring at least 10 mm usually reflect the grade and stage of CHC reliably. Relatively little improvement in diagnostic accuracy is obtained with longer specimens.  相似文献   
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