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1.
Laterality of cross-modal spatial processing 总被引:1,自引:0,他引:1
J O Adams P D Duda 《Cortex; a journal devoted to the study of the nervous system and behavior》1986,22(4):539-552
This study examined the laterality of spatial-form perception in normal adults using a cross-modal matching paradigm involving visual and tactile processing. Randomly generated eight-point and 12-point Vanderplas and Garvin (1959) patterns were used as the stimuli. In a visual-to-tactile task, a lateralized visual pattern was followed immediately by a haptic task requiring subjects to discriminate which of two simultaneously felt shapes matched the visual pattern. In a tactile-to-visual task, subjects decided which of two simultaneously felt shapes matched a lateralized visual pattern presented after haptic manipulation. There were no main effects for laterality or for sex differences. Matching accuracy was better in the visual-to-tactile task and for less complex stimuli. A visual field by feeling hand interaction showed best recognition accuracy when visual-feeling hand combinations on the same side of the body were used in the two matching tasks. These data reflect a stimulus-response compatibility explanation of spatial-form perception that is consistent with a behavioral and not a cerebral asymmetry model. 相似文献
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Leonard A. Jason PhD Steven B. Pokorny PhD Monica Adams MPH Annie Topliff MA Courtney Harris BA Yvonne Hunt PhD 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》2009,18(5):367-374
This study evaluated the effects of tobacco Purchase, Use and Possession (PUP) laws on student perceptions of adolescent tobacco use within towns and schools. Twenty‐four towns were randomly assigned into two conditions, the experimental condition (E PUP) involved efforts to increase both PUP law enforcement and reduce minors' access to commercial sources of tobacco, whereas the control condition (C) focused only on efforts to reduce minors' access to commercial sources of tobacco. A hierarchical linear modeling analytical approach was selected due to the multilevel data and nested design. The present study found that over time, youth in the experimental PUP condition observed less youth tobacco usage at school and in their town, and perceived lower rates of tobacco among their peers at school and among friends than youth in the control condition. The findings suggest that PUP law enforcement might be used to strengthen community norms against youth tobacco use. 相似文献
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Chemically distinct rat olivocochlear neurons. 总被引:6,自引:0,他引:6
We have produced a neurochemical map of the cell bodies of origin of the cochlear efferent terminals in rat by combining glutamic acid decarboxylase (GAD), choline acetyltransferase (ChAT), or calcitonin gene-related peptide (CGRP) immunocytochemistry with retrograde transport of horseradish peroxidase. The locations of cochlear efferent cell bodies are in general agreement with the medial and lateral systems described by White and Warr (J. Comp. Neurol. 219:203-214, 1983) with some minor modifications. The lateral system consists of at least two pools of chemically distinct neurons located within the lateral superior olive (LSO) ipsilateral to the injected cochlea. One pool immunostains with an antibody to GAD while the other immunostains with antibodies to ChAT and to CGRP. The medial efferent system consists of periolivary neurons that are almost exclusively large and ChAT-positive but CGRP-negative. They are located both ipsilateral and contralateral to the cochlea they project to. There are a few GAD-positive small neurons in the medioventral and rostral periolivary regions that project ipsilaterally, but these may prove tobe ectopic neurons. The ipsilateral lateroventral periolivary region (LVPO) contains some efferent neurons, all of which are ChAT-positive but CGRP-negative. Additional cochlear efferent neurons, some of which are ChAT-positive and others GAD-positive, are present within and immediately dorsal to the fiber capsule surrounding the medial limb, and to a lesser extent the lateral limb, of the ipsilateral LSO. Not all GAD-positive or ChAT-positive olivary cells project to the cochlea. We have complemented the results in the brainstem by demonstrating two immunocytochemically distinct populations of efferent terminals in the cochlea simultaneously, one CGRP-positive and the other GAD-positive. Approximately equal numbers of boutons immunoreactive for both markers are present beneath inner hair cells throughout the entire length of the cochlea. Surprisingly high numbers of GAD-positive and CGRP-positive boutons are also present on outer hair cells, with each class having its spatially and morphologically distinct features. The lack of CGRP-positive periolivary cells that are retrogradely labeled by cochlear injections of HRP suggests that the lateral olivocochlear system sends projections to outer hair cells. Our results raise questions about species differences in the organization of targets of the lateral and medial olivocochlear systems. 相似文献
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J P Murphy A V Adyanthaya P R Adams J D McArthur W E Walker 《The Annals of thoracic surgery》1987,43(3):323-325
Pulmonary artery aneurysms are rare lesions for which operative management is not frequently undertaken. When operation is indicated, central lesions involving the pulmonary trunk, right main pulmonary artery, or left main pulmonary artery are repaired using cardiopulmonary bypass. Peripheral aneurysms in segmental intrapulmonary arteries have been managed most frequently by lobectomy, but occasionally by aneurysmectomy and pulmonary arterial repair. We used cardiopulmonary bypass for peripheral pulmonary aneurysmectomy in a patient with limited respiratory reserve because he had undergone prior contralateral bilobectomy; this allowed controlled resection while preserving a maximal amount of pulmonary parenchyma. 相似文献
8.
Operative cholangiography 总被引:3,自引:0,他引:3
E H Shively T J Wieman A L Adams R B Romines R N Garrison 《American journal of surgery》1990,159(4):380-4; discussion 385
The value of operative cholangiography in the management of biliary tract disease has been questioned. To better define the role of cholangiography, we reviewed 579 consecutive cholecystectomies done by 1 group of surgeons in a small rural practice over 8 years. Cholangiography demonstrated unsuspected common bile duct disease in 5% of the procedures, while 12% of the patients were spared an unnecessary choledochotomy after a normal cholangiogram was obtained. There was no morbidity, mortality, or prolongation of the hospital stay attributed to the cholangiographic procedure. These findings bolster the argument for routine cholangiography as a safe, effective, and helpful screening examination for patients who are at risk for having common bile duct disease. 相似文献
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The flow cytometric crossmatch and early renal transplant loss 总被引:3,自引:0,他引:3
R J Mahoney K A Ault S R Given R J Adams A C Breggia P A Paris G E Palomaki S A Hitchcox B W White J Himmelfarb 《Transplantation》1990,49(3):527-535
Data from this retrospective study indicate that a positive two-color T and/or B cell flow cytometric crossmatch (FCXM) is predictive of early renal allograft loss (less than 2 months) in cadaveric kidney donor recipients who had a negative crossmatch by the antihuman globulin complement-dependent cytotoxicity technique. Among 90 cadaveric kidney donor recipients (67 primary, 23 regrafts), 14 (8 primary, 6 regrafts) lost their renal allografts within 2 months, and 10 of the 14 were FCXM positive and HLA sensitized. The remaining 76 allografts survived beyond 2 months, 12 of which were FCXM-positive. Thus, the FCXM sensitivity rate for detecting early graft loss was 71%, and the specificity rate was 84%. Cadaveric graft-loss rates at 2 months were 33% for primary and 60% for FCXM-positive regrafts in contrast to 7% for primary and 0% for FCXM-negative regrafts. The difference in early graft loss between FCXM-positive and FCXM-negative recipients was statistically significant (P less than 0.0001). Subset analyses of FCXM-positive graft recipients indicate: (1) previous early graft loss contraindicates transplantation of an FXCM-positive regraft (P = 0.03); and (2) panel reactive antibody (PRA) less than or equal to 10% at crossmatch is not associated with early graft loss (P = 0.04). There was no significant difference in 1-year graft survival between primary and regrafts in either FCXM-negative recipients (85% vs. 77%, respectively) or FCXM-positive recipients (67% vs. 40%). All 12 of the FCXM-positive primary and regrafts that survived 2 months continued to function at 2 years. Stepwise logistic regression analysis of 5 independent predictor variables (FCXM status, gender, primary vs. regraft status, PRA level, and HLA mismatched antigens) indicated that the FCXM test was the best predictor of early graft loss. When FCXM results of the 90 cadaveric graft recipients were ranked in three groups, an FCXM channel shift of 29 or greater (third tertile) on a 1024 channel log scale was associated with a 7.0-fold (95% confidence interval 1.9-25.5) increased risk of early graft failure when compared to the first two tertiles. These data indicate that the FCXM offers an additional approach for identifying sensitized patients at risk of early renal allograft loss. 相似文献
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