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61.
Rebecca J Sommer Adam J Hume Jessica M Ciak John J Vannostrand Megan Friggens Mary K Walker 《Toxicological sciences》2005,83(2):363-371
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase. 相似文献
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W. E. Adam M. Clausen D. Hellwig E. Henze F. Bitter 《European journal of nuclear medicine and molecular imaging》1988,13(12):637-647
Myocardial scanning (MS) and radionuclide ventriculography (RNV) are the foundation of nuclear cardiology. These procedures aim in two completely different directions: RNV tries to image heart motion, that is, mechanical (pump) function, and therefore belongs to the group of first-order functional imaging (FI, imaging mechanical function), whereas MS is based on myocardial metabolism, and therefore can be attributed to third-order functional imaging (metabolism). This statement is relevant for the assessment of the clinical position of RNV: Third-order (metabolism) functional imaging is the domain of nuclear medicine (NM), whereas first-order FI has to face the competition of alternative noninvasive procedures such as ultrasound (US), digital subtraction angiography (DSA), computer tomography (CT), and nuclear magnetic resonance (NMR). The domain of RNV includes stages two (acute infarction) and three (postinfarction period) of coronary arterial disease (CAD). The advantageous combination of quantitative data on global, left ventricular (LV) function and imaging of regional motion ensures the superiority of RNV over US. However, RNV is inferior to MS in physical examinations in the preinfarction stage of CAD, whereas US is clearly inferior to both NM procedures. Recent progress could be attained by gated SPECT (GASPECT). A proposal is presented for simplification of this time-consuming procedure. Technetium-labeled isonitriles offer the chance for the combination of perfusion-motion imaging of the myocardium. However, even standard RNV offers new possibilities. The multitude of parameters produced by quantitation has not yet been exploited completely. This can be done by discriminant analysis. The computer finds out an optimal subset from the whole set of parameters for the solution of a significant clinical problem. The software learns to find the label of a special pathognomonic entity. This computer work is supported by a relational data bank (Oracle) and an optical disk. Two examples for the effectiveness of the computer in problem solving are presented. It is concluded that RNV, even in the very competitive class of first-order functional imaging, enjoys a preferred position. The future indeed seems brighter because labeled isonitriles offer the chance for the combination of perfusion-motion imaging of the myocardium.Dedicated to Prof. Heinz Hundeshagen on the occasion of his 60th birthday 相似文献
66.
Tomasz Trojanowski Jerzy P ceszyński Krzysztof Turowski Stanisław Kamiński Igor Gościński Marian Reinfus Tadeusz Krzyszkowski Marek Pyrich Adam Bielawski Czesława Leszczyk Barbara Bendarzewska Andrzej Staszczak Halina Koźniewska 《Journal of neuro-oncology》1988,6(3):285-291
A prospective, randomized trial evaluates the effects of two postoperative treatment regimens on survival in 198 adult patients with supratentorial gliomas. All patients were irradiated with 6 000 rads after possibly radical removal of tumors. CCNU administration in the dosis of 100 mg/sq m of body surface every 6–8 weeks following surgery proved to have no significant effect on the survival of patients. The median survival time in patients receiving radiation therapy alone was 61±7 weeks, while in those receiving additional chemotherapy was 56±4 weeks. Tumor histological malignancy and patients age were found to be the only important prognostic factors, irrespective of the treatment modality.
Address for offprints: T Trojanowski, Department of Neurosurgery, Medical School, Jaczewskiego 8, 20-950 Lublin, Poland 相似文献
67.
Effects of chemical mediators of anaphylaxis on ciliary function 总被引:2,自引:0,他引:2
Adam Wanner M.D. David Maurer Ph.D. William M. Abraham Ph.D. Zsolt Szepfalusi Marek Sielczak M.D. 《The Journal of allergy and clinical immunology》1983,72(6):663-667
We assessed the effects of selected chemical mediators of anaphylaxis on CBF in vitro. Ciliated epithelial cells were obtained from the trachea of conscious sheep with a cytology brush and suspended in a perfusion chamber containing KH. Ciliary activity was viewed microscopically and recorded on videotape for subsequent slow-motion analysis of CBF. Prostaglandin E1 (10(-8) M to 10(-6) M), prostaglandin E2 (10(-10) M to 10(-6) M), and leukotriene-C4 (10(-8) M) increased CBF between 7% and 33%. Histamine caused ciliostimulation only at the relatively high concentrations above 10(-5) M (7% increase in CBF), whereas prostaglandin F2 alpha (10(-10) M and 10(-6) M) was without effect. In no preparation was ciliary discoordination observed. These findings indicate that several chemical mediators of anaphylaxis stimulate CBF and that the previously described impairment of mucociliary transport in stable allergic asthma or antigen-induced bronchoconstriction is probably not caused by a primary alteration of ciliary function. 相似文献
68.
Atypical sexual behavior during sleep 总被引:5,自引:0,他引:5
OBJECTIVE: This article reports a case series of atypical sexual behavior during sleep, which is often harmful to patients or bed partners. METHODS: Eleven subjects underwent clinical evaluation of complaints of sleep-related atypical sexual behavior. Complaints included violent masturbation, sexual assaults, and continuous (and loud) sexual vocalizations during sleep. One case was a medical-legal case. Sleep logs, clinical evaluations, sleep questionnaires, structured psychiatric interviews, polysomnography, actigraphy, home electroencephalographic monitoring during sleep, and clinical electroencephalographic monitoring while awake and asleep were used to determine clinical diagnoses. RESULTS: Atypical sexual behaviors during sleep were associated with feelings of guilt, shame, and depression. Because of these feelings, patients and bed partners often tolerated the abnormal behavior for long periods of time without seeking medical attention. The following pathologic sleep disorders were demonstrated on polysomnography: partial complex seizures, sleep-disordered breathing, stage 3 to 4 non-rapid eye movement (REM) sleep parasomnias, and REM sleep behavior disorder. These findings were concurrent with morning amnesia. CONCLUSIONS: The atypical behaviors were related to different syndromes despite the similarity of complaints from bed partners. In most cases the disturbing and often harmful symptoms were controlled when counseling was instituted and sleep disorders were treated. In some cases treatment of seizures or psychiatric disorders was also needed. Clonazepam with simultaneous psychotherapy was the most common successful treatment combination. The addition of antidepressant or antiepileptic medications was required in specific cases. 相似文献
69.
The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC), and specific airway conductance (SGaw) were determined before and during bronchial provocation with ragweed extract in 27 subjects with ragweed hypersensitivity and a history of either bronchial asthma (16 subjects) or allergic rhinitis (11 subjects). Mean baseline SGaw was significantly lower while mean volume of isoflow (Visov) and FrC were significantly higher in subjects with bronchial asthma. During antigen challenge, 10 of 16 subjects with bronchial asthma (63%) and five of 11 subjects with allergic rhinitis (45%) showed a greater than 35% decrease in SGaw ("reactors"): mean relative decreases in SGaw from baseline were 46% and 53%, respectively. The remaining subjects showed a less than 35% decrease in SGaw ("nonreactors") with mean relative decreases of 9% (allergic asthma) and 6% (allergic rhinitis). Mean Visov increased in all subjects with bronchial asthma and in eight of 11 subjects with allergic rhinitis. A significant increase in FRC (6%) was seen only in the "reactors" with bronchial asthma. Following antigen challenge, the beta adrenergic agonist, isoetharine, increased SGaw and decreased Visov. We conclude that in asymptomatic subjects with ragweed hypersensitivity, (1) central and peripheral airway function is more abnormal in subjects with bronchial asthma than in subjects with allergic rhinitis, (2) subjects of both groups show quantitatively and qualitatively comparable airway responses during antigen challenge with a decrease in SGaw or an increase in Visov, possibly representing increase in central and/or peripheral airflow resistance, respectively, (3) Visov may be a more sensitive indicator of airway response to antigen challenge than SGaw, and (4) the bronchodilator effects of a beta adrenergic agonist on antigen-induced bronchospasm are similar in both groups. 相似文献
70.
Guy RJ Breschkin AM Keenan CM Catton MG Enriquez AM Hellard ME 《Journal of acquired immune deficiency syndromes (1999)》2005,38(4):495-499
Between 1999 and 2000, new diagnoses of HIV in Victoria (Australia) rose by 41%, from 140 to 197. In this time period, sera from new HIV diagnoses were tested using the Organon Teknika "detuned" enzyme immunoassay (EIA). We compared the results of the detuned EIA with incident infections defined by surveillance (on the basis of a previous negative or indeterminate HIV test and/or a seroconversion illness within the 12 months preceding HIV diagnosis). Of 317 specimens, 97 (31%) incident infections and 114 (36%) recent infections were detected using surveillance and detuned EIA, respectively. The detuned assay misclassified 11 cases with AIDS and 2 cases with CD4 counts < or = 200 micro3 (probable long-standing infections) as recent infections and was unable to identify 31 (32%) of 97 cases previously classified as incident cases by surveillance. The assay detected an extra 35 recent infections that were previously classified as nonincident by surveillance. By combining the detuned assay and surveillance, 132 (42%) incident infections were identified from 317 specimens, 36% more than surveillance alone. We recommend that a detuned assay or similar test become part of the routine strategy to identify incident infections in Victoria. Incident infections provide important information for targeting prevention strategies and the opportunity to interrupt ongoing viral transmission. 相似文献