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821.
ObjectivesThe aim of this study was to define predictors of prosthesis-patient mismatch (PPM) and its impact on mortality after transcatheter aortic valve replacement (TAVR) with self-expandable valves (SEVs) in patients with small annuli.BackgroundTAVR seems to reduce the risk for PPM compared with surgical aortic valve replacement, especially in patients with small aortic annuli. Nevertheless, predictors and impact of PPM in this population have not been clarified yet.MethodsPredictors of PPM and all-cause mortality were investigated using multivariable logistic regression analysis from the cohort of the TAVI-SMALL (International Multicenter Registry to Evaluate the Performance of Self-Expandable Valves in Small Aortic Annuli) registry, which included patients with severe aortic stenosis and small annuli (annular perimeter <72 mm or area <400 mm2 on computed tomography) treated with transcatheter SEVs: 445 patients with (n = 129) and without (n = 316) PPM were enrolled.ResultsIntra-annular valves conferred increased risk for PPM (odds ratio [OR]: 2.36; 95% confidence interval [CI]: 1.16 to 4.81), while post-dilation (OR: 0.46; 95% CI: 0.25–0.84) and valve oversizing (OR: 0.53; 95% CI: 0.28–1.00) seemed to protect against PPM occurrence. At a median follow-up of 354 days, patients with severe PPM, but not those with moderate PPM, had a higher all-cause mortality rate compared with those without PPM (log-rank p = 0.008). Multivariable Cox regression confirmed severe PPM as an independent predictor of all-cause mortality (hazard ratio: 4.27; 95% CI: 1.34 to 13.6).ConclusionsAmong patients with aortic stenosis and small aortic annuli undergoing transcatheter SEV implantation, use of intra-annular valves yielded higher risk for PPM; conversely, post-dilation and valve oversizing protected against PPM occurrence. Severe PPM was independently associated with all-cause mortality.  相似文献   
822.
As transcatheter aortic valve replacement becomes a more dominant treatment option across all risk profiles, the frequency of encountering patients with multivalvular disease will increase. Furthermore, percutaneous interventions to treat other valvular lesions are also evolving. Understanding the clinical implications and treatment options for a second valvular lesion is becoming increasingly important to guide heart team decisions, and this paper aims to review the evidence around these situations. Diagnosis of multivalvular disease can be challenging because of changes in physiology. There are little randomized data to guide therapy in multivalvular disease. Multidisciplinary heart team decisions can be invaluable in integrating the plethora of clinical, hemodynamic, and imaging data on which an optimal management strategy can be planned. Prospective studies to assess the role of structural valve interventions in the transcatheter aortic valve replacement era would greatly help improve outcomes for structural heart patients.  相似文献   
823.
BackgroundTrastuzumab is highly effective for human epidermal growth factor receptor type 2 (HER2)–positive breast cancer but is associated with a decline in left ventricular ejection fraction.ObjectivesThe purpose of this study was to determine whether angiotensin-converting enzyme inhibitors or beta-blockers reduce the rate of trastuzumab-induced cardiotoxicity (left ventricular ejection fraction decrease >10%, or >5% if below 50%) and limit treatment interruptions.MethodsIn this double-blind, multicenter, placebo-controlled trial, cardiotoxicity and treatment interruptions in patients with HER2-positive breast cancer treated with trastuzumab for 12 months were evaluated over a 2-year period. Patients were stratified by anthracycline use and then randomized to receive lisinopril, carvedilol, or placebo.ResultsThe study included 468 women, age 51 ± 10.7 years. For the entire cohort, cardiotoxicity was comparable in the 3 arms and occurred in 32% of patients on placebo, 29% on carvedilol, and 30% on lisinopril. For patients receiving anthracyclines, the event rates were higher in the placebo group (47%) than in the lisinopril (37%) and the carvedilol (31%) groups. Cardiotoxicity-free survival was longer on both carvedilol (hazard ratio: 0.49; 95% confidence interval: 0.27 to 0.89; p = 0.009) and lisinopril (hazard ratio: 0.53; 95% confidence interval: 0.30 to 0.94; p = 0.015) than on placebo. In the whole cohort, as well as in the anthracycline arm, patients on active therapy with either angiotensin-converting enzyme inhibitor or beta-blockers experienced fewer interruptions in trastuzumab than those on placebo.ConclusionsIn patients with HER2-positive breast cancer treated with trastuzumab, both lisinopril and carvedilol prevented cardiotoxicity in patients receiving anthracyclines. For such patients, lisinopril or carvedilol should be considered to minimize interruptions of trastuzumab. (Lisinopril or Coreg CR in Reducing Side Effects in Women With Breast Cancer Receiving Trastuzumab; NCT01009918)  相似文献   
824.
OBJECTIVE: To evaluate an innovative approach to continuing medical education, an outreach intervention designed to improve performance rates of breast cancer screening through implementation of office systems in community primary care practices. DESIGN: Randomized, controlled trial with primary care practices assigned to either the intervention group or control group, with the practice as the unit of analysis. SETTING: Twenty mostly rural counties in North Carolina. PARTICIPANTS: Physicians and staff of 62 randomly selected family medicine and general internal medicine practices, primarily fee-for-service, half group practices and half solo practitioners. INTERVENTION: Physician investigators and facilitators met with practice physicians and staff over a period of 12 to 18 months to provide feedback on breast cancer screening performance, and to assist these primary care practices in developing office systems tailored to increase breast cancer screening. MEASUREMENTS AND MAIN RESULTS: Physician questionnaires were obtained at baseline and follow-up to assess the presence of five indicators of an office system. Three of the five indicators of office systems increased significantly more in intervention practices than in control practices, but the mean number of indicators in intervention practices at follow-up was only 2.8 out of 5. Cross-sectional reviews of randomly chosen medical records of eligible women patients aged 50 years and over were done at baseline (n=2,887) and follow-up (n=2,874) to determine whether clinical breast examinations and mammography, were performed. Results for mammography were recorded in two ways, mention of the test in the visit note and actual report of the test in the medical record. These reviews showed an increase from 39% to 51% in mention of mammography in intervention practices, compared with an increase from 41% to 44% in control practices (p=.01). There was no significant difference, however, between the two groups in change in mammograms reported (intervention group increased from 28% to 32.7%; control group increased from 30.6% to 34.0%, p=.56). There was a nonsignificant trend (p=.06) toward a greater increase in performance of clinical breast examination in intervention versus control practices. CONCLUSIONS: A moderately intensive outreach intervention to increase rates of breast cancer screening through the development of office systems was modestly successful in increasing indicators of office systems and in documenting mention of mammography, but had little impact on actual performance of breast cancer screening. At follow-up, few practices had a complete office system for breast cancer screening. Outreach approaches to assist primary care practices implement office systems are promising but need further development. Presented in part at the 19th annual meeting of the Society of General Internal Medicine, Washington, DC, May 1996. This research was supported under grant CA 54343-02 from the National Cancer Institute.  相似文献   
825.
Background and aimThe present study was conducted to explore the stratified and joint effects of age at menopause and body mass index (BMI) with the risk of type 2 diabetes mellitus (T2DM) in Chinese rural adults.Methods and resultsA total of 15,406 postmenopausal Chinese women were included in this study. Multivariable logistic regression analysis was used to quantify the stratified and joint effects of age at menopause and BMI on T2DM. Overall, the mean age at menopause and BMI was 48.8 ± 4.7 years and 25.1 ± 3.6 kg/m2, respectively. In general, data suggest that: 1) women with BMI ≥ 24 had a higher risk of T2DM, irrespective of age at menopause; 2) in women with BMI < 24, later menopause had a higher risk of T2DM (OR, 1.52; 95% CI, 1.16–2.01); 3) the risk of T2DM was higher only in patients with early or normal age at menopause and BMI ≥ 24, with 0R (95% CI) of (1.58, 1.28–1.94) and (1.48, 1.31–1.67), respectively.ConclusionOur findings suggest that: 1) women with BMI ≥ 24 had a higher risk of T2DM, irrespective of age at menopause; 2) in women with BMI < 24, a higher risk of T2DM was found only in those with later menopause; 3) women with later menopause had a higher risk of T2DM, irrespective of BMI; 4) in patients with early or normal age at menopause, a higher risk of T2DM was found only in patients with BMI ≥ 24.The Chinese Clinical Trial RegistrationChiCTR–OOC–1500669(URL:http://www.chictr.org.cn/showproj.aspx?proj=11375)  相似文献   
826.
Central illustration. Six-month mortality according to category of coronary artery calcium (CAC). The mortality rate increased with the magnitude of calcifications according to a visual scoring of CAC on chest computed tomography. CAC was associated with 6-month mortality, independent of conventional cardiovascular risk-factors, in patients hospitalized for coronavirus disease 2019 without known atheromatous disease. CI: confidence interval; HR: hazard ratio.
  相似文献   
827.
828.
ObjectivesThe aim of this study was to compare the rate of proximal radial artery occlusion (RAO) with Doppler ultrasound between distal and conventional radial access 24 h and 30 days after a transradial coronary procedure.BackgroundThe use of distal radial access to prevent proximal RAO (PRAO) in the proximal segment at 24 h and 30 days after a procedure, compared with conventional radial access, is unknown.MethodsThis was a prospective, comparative, longitudinal, randomized study. A total of 282 patients were randomized to either proximal radial access (n = 142) or distal radial access (n = 140) to evaluate the superiority of the distal approach in the prevention of PRAO with Doppler ultrasound 24 h and 30 days after a transradial coronary procedure.ResultsIn the per protocol analysis, the rates of PRAO at 24 h and 30 days were 8.4% and 5.6% in the proximal group and 0.7% and 0.7% in the distal group, respectively (24 h: odds ratio [OR]: 12.8; 95% confidence interval [CI]: 1.6 to 100.0; p = 0.002; 30 days: OR: 8.2; 95% CI: 1.0 to 67.2; p = 0.019). In an intention-to-treat analysis, the 24-h and 30-day rates of PRAO were 8.8% and 6.4% for proximal radial access and 1.2% and 0.6% in the distal radial access group (24 h: OR: 7.4; 95% CI: 1.6 to 34.3; p = 0.003; 30 days: OR: 10.6; 95% CI: 1.3 to 86.4; p = 0.007).ConclusionsDistal radial access prevents RAO in the proximal segment at 24 h and 30 days after the procedure compared with conventional radial access.  相似文献   
829.
830.
In this study, we evaluated the effectiveness of the statistic, Weighted Coherence in relation to the average or mean coherence in a particular frequency band after cross-spectral analysis. In time domain, correlation coefficient explains the relationship between two variables of interest, and a similar statistic in frequency domain using cross-spectral analysis is referred to as coherence, which is equivalent to the squared correlation coefficient and ranges from zero to unity. In this study, we show that weighted coherence is much more sensitive to various challenges within the same subject and also may be a more sensitive indicator of group differences in different frequency bands. Our data on normal subjects and patients with panic disorder during supine and standing postures during normal breathing, and also at different breathing rates throw new light on the sensitivity of this previously described novel index to quantify coherence between two related time series such as beat-to-beat heart rate and QT interval.  相似文献   
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