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991.
992.
Thomas S. Rector Brent C. Taylor Timothy J. Wilt 《Journal of general internal medicine》2012,27(1):94-101
A number of new biological markers are being studied as predictors of disease or adverse medical events among those who already have a disease. Systematic reviews of this growing literature can help determine whether the available evidence supports use of a new biomarker as a prognostic test that can more accurately place patients into different prognostic groups to improve treatment decisions and the accuracy of outcome predictions. Exemplary reviews of prognostic tests are not widely available, and the methods used to review diagnostic tests do not necessarily address the most important questions about prognostic tests that are used to predict the time-dependent likelihood of future patient outcomes. We provide suggestions for those interested in conducting systematic reviews of a prognostic test. The proposed use of the prognostic test should serve as the framework for a systematic review and to help define the key questions. The outcome probabilities or level of risk and other characteristics of prognostic groups are the most salient statistics for review and perhaps meta-analysis. Reclassification tables can help determine how a prognostic test affects the classification of patients into different prognostic groups, hence their treatment. Review of studies of the association between a potential prognostic test and patient outcomes would have little impact other than to determine whether further development as a prognostic test might be warranted. 相似文献
993.
Benign smooth muscle proliferations are relatively rare in the oral cavity. Most are classified as angioleiomyomas, some as hamartomatous growths and a few as cutaneous-type leiomyomas. We present two cases of benign smooth muscle proliferations in the tongue, provide a review, briefly discuss histogenesis and offer a clinico-pathological differential diagnosis. 相似文献
994.
Giovanni Merolla Arpit C. Dave Francesco Pegreffi Lorenza Belletti Giuseppe Porcellini 《Musculoskeletal surgery》2012,96(1):93-99
Alkaptonuria is a rare hereditary metabolic disease of autosomal recessive inheritance, resulting from deficiency of the enzyme homogentisic acid oxidase. The term “alkaptonuria” was first used in 1859 by Boedeker to describe a patient’s urinary reducing compound, and in 1866, Virchow coined the term “ochronosis” due to typical yellow pigmentation. Deposition of this pigment in articular cartilage leads to ochronotic arthropathy, the most incapacitating complication of alkaptonuria. We report a rare case of shoulder ochronotic arthritis, treated with total shoulder arthroplasty, achieving a successful long-term clinical and radiological outcomes. 相似文献
995.
Muhammad Arif 《Journal of medical systems》2012,36(3):1173-1181
In pattern classification problems, feature extraction is an important step. Quality of features in discriminating different classes plays an important role in pattern classification problems. In real life, pattern classification may require high dimensional feature space and it is impossible to visualize the feature space if the dimension of feature space is greater than four. In this paper, we have proposed a Similarity-Dissimilarity plot which can project high dimensional space to a two dimensional space while retaining important characteristics required to assess the discrimination quality of the features. Similarity-dissimilarity plot can reveal information about the amount of overlap of features of different classes. Separable data points of different classes will also be visible on the plot which can be classified correctly using appropriate classifier. Hence, approximate classification accuracy can be predicted. Moreover, it is possible to know about whom class the misclassified data points will be confused by the classifier. Outlier data points can also be located on the similarity-dissimilarity plot. Various examples of synthetic data are used to highlight important characteristics of the proposed plot. Some real life examples from biomedical data are also used for the analysis. The proposed plot is independent of number of dimensions of the feature space. 相似文献
996.
Eystratios G. Keramidas Dimitris Maroulis Dimitris K. Iakovidis 《Journal of medical systems》2012,36(3):1271-1281
In this paper, we present a computer-aided-diagnosis (CAD) system prototype, named TND (Thyroid Nodule Detector), for the detection of nodular tissue in ultrasound (US) thyroid images and videos acquired during thyroid US examinations. The proposed system incorporates an original methodology that involves a novel algorithm for automatic definition of the boundaries of the thyroid gland, and a novel approach for the extraction of noise resilient image features effectively representing the textural and the echogenic properties of the thyroid tissue. Through extensive experimental evaluation on real thyroid US data, its accuracy in thyroid nodule detection has been estimated to exceed 95%. These results attest to the feasibility of the clinical application of TND, for the provision of a second more objective opinion to the radiologists by exploiting image evidences. 相似文献
997.
Medical Records Department (MRD) is an important unit for evaluating and planning of care services. The goal of this study is evaluating the performance of the Medical Records Departments (MRDs) of the selected hospitals in Isfahan, Iran by using Analytical Hierarchy Process (AHP). This was an analytic of cross-sectional study that was done in spring 2008 in Isfahan, Iran. The statistical population consisted of MRDs of Alzahra, Kashani and Khorshid Hospitals in Isfahan. Data were collected by forms and through brainstorm technique. To analyze and perform AHP, Expert Choice software was used by researchers. Results were showed archiving unit has received the largest importance weight with respect to information management. However, on customer aspect admission unit has received the largest weight. Ordering weights of Medical Records Departments’ Alzahra, Kashani and Khorshid Hospitals in Isfahan were with 0.394, 0.342 and 0.264 respectively. It is useful for managers to allocate and prioritize resources according to AHP technique for ranking at the Medical Records Departments. 相似文献
998.
999.
Tiffany R. Morris Catherine Cho Valentina Dilda James M. Shine Sharon L. Naismith Simon J.G. Lewis Steven T. Moore 《Gait & posture》2013,37(2):326-329
The current ‘gold standard’ for clinical evaluation of freezing of gait (FOG) in Parkinson's disease (PD) is determination of the number of FOG episodes from video by independent raters. We have previously described a robust technique for objective FOG assessment from lower-limb acceleration. However, there is no existing method for validation of autonomous FOG measures in the absence of video documentation. In this study we compared the results of clinical evaluation of FOG from computer-generated animations (derived from body-mounted inertial sensors) during a timed up and go test with the ‘gold standard’ of clinical video assessment, utilizing a cohort of 10 experienced raters from four PD centers. Agreement between the 10 clinical observers for scoring of FOG from computer animations was more robust for the relative duration of freeze events (percent time frozen; intraclass correlation coefficient of 0.65) than number of FOG episodes, and was comparable with clinical evaluation of the patient from video (intraclass correlation coefficient 0.73). This result suggests that percent time frozen should be considered (along with number of FOG events) to better convey FOG severity. The ability of clinical observers to quantify FOG from computer-generated animation derived from lower-limb motion data provides a potential approach to validation of accelerometry-based FOG identification outside of the clinic. 相似文献
1000.
Objective. To review studies of patient-centered asthma education. Method. CINAHL, Medline, Psycinfo, Eric, PsycARTICLES, and web of science databases were searched. Results Asthma education programs are often based on health behavior theories. Many studies lack rigor in the assessment of the program's efficacy and effectiveness. Asthma education that promotes self-management primarily uses a problem-based approach. Few studies have examined the way educators teach and patients learn. Patient-centered approaches to education have mainly focused on communication between the patient and the health professional. Decision making as part of shared responsibility may vary with every patient. Patient-centered care shares similarities with the Self-Determination Theory as a learner-centered approach to education. Conclusions. Many asthma education studies have been completed with varying levels of efficacy and effectiveness reported. Most programs focus on changing behavior with few studies examining educator behavior and/or the patient's learning styles. With a patient-centered approach being the preferred model of care, the incorporation of learner-centered approaches to patient education may prove useful in the future. 相似文献