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排序方式: 共有4079条查询结果,搜索用时 15 毫秒
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Reza Fardanesh Maria Adele Marino Daly Avendano Doris Leithner Katja Pinker Sunitha B. Thakur 《Journal of magnetic resonance imaging : JMRI》2019,50(4):1033-1046
Proton magnetic resonance spectroscopy (MRS) is a promising noninvasive diagnostic technique for investigation of breast cancer metabolism. Spectroscopic imaging data may be obtained following contrast‐enhanced MRI by applying the point‐resolved spectroscopy sequence (PRESS) or the stimulated echo acquisition mode (STEAM) sequence from the MR voxel encompassing the breast lesion. Total choline signal (tCho) measured in vivo using either a qualitative or quantitative approach has been used as a diagnostic test in the workup of malignant breast lesions. In addition to tCho metabolites, other relevant metabolites, including multiple lipids, can be detected and monitored. MRS has been heavily investigated as an adjunct to morphologic and dynamic MRI to improve diagnostic accuracy in breast cancer, obviating unnecessary benign biopsies. Besides its use in the staging of breast cancer, other promising applications have been recently investigated, including the assessment of treatment response and therapy monitoring. This review provides guidance on spectroscopic acquisition and quantification methods and highlights current and evolving clinical applications of proton MRS. Level of Evidence 5 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2019. 相似文献
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Chang Natalie Hong Siu Kumakura Yoshitaka Møller Arne Linnet Jakob Bender Dirk Doudet Doris J. Vafaee Manouchehr Seyedi Gjedde Albert 《Brain imaging and behavior》2022,16(1):355-365
Brain Imaging and Behavior - We asked if sensation-seeking is linked to premorbid personality characteristics in patients with addictive disorders, or the characteristics follow the... 相似文献
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Sarah Bonk MD Martina Kluth PhD Kristina Jansen MD Claudia Hube-Magg PhD Georgia Makrypidi-Fraune PhD Doris Höflmayer MD Sören Weidemann MD Katharina Möller MD Ria Uhlig MD Franziska Büscheck MD Andreas M. Luebke MD Eike Burandt MD Till S. Clauditz MD Stefan Steurer MD Thorsten Schlomm MD Hartwig Huland MD Hans Heinzer MD Guido Sauter MD Ronald Simon PhD David Dum MD 《The Prostate》2020,80(13):1097-1107
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Doris Heger-Mahn Günther Pabst Angelika Dienel Sandra Schl?fke Christine Klipping 《Drugs in R&D》2014,14(4):265-272
Purpose
Silexan is an oral Lavender oil preparation with proven anxiolytic efficacy. Given the high prevalence of anxiety and restlessness in younger women, oral contraceptives and Silexan will likely be co-administered.Methods
A double-blind, randomised, 2-period crossover study was performed to investigate the effects of Silexan on the pharmacokinetics and pharmacodynamics of Microgynon®, a combination oral contraceptive containing ethinyl estradiol 0.03 mg (EE) and levonorgestrel 0.15 mg (LNG) in healthy, fertile, adult females. During 2 consecutive cycles of 28 days, oral contraception was given for 21 days combined with 1 × 160 mg/day Silexan or placebo. Plasma concentration–time profiles of EE and LNG were obtained on day 18 ± 1 up to 24 h after dosing. The primary outcome measure was the area under the concentration–time curve over a dosing interval of τ = 24 h (AUCτ) for EE and LNG plasma levels. An interaction with Silexan was formally excluded if the 90 % confidence interval for the AUCτ ratio during co-administration with Silexan or placebo was included within the range of 0.80–1.25. Secondary outcomes included EE and LNG peak concentration (Cmax) and time to Cmax (tmax), follicle size, endometrial thickness, the Hoogland score, and serum levels of estradiol, progesterone, and sex hormone-binding globulin.Results
A total of 24 women (mean age 27.3 years; mean body mass index 22.2 kg/m2) participated. The confidence intervals for the EE and LNG AUCτ and Cmax ratios fell within the pre-specified limits, indicating no interaction (point estimates [Silexan/placebo] AUCτ EE 0.97, LNG 0.94; Cmax EE 0.99, LNG 0.96). For LNG, tmax was slightly delayed. No secondary outcome indicated any impairment of contraceptive efficacy.Conclusions
Co-administration of Silexan did not affect the efficacy of a combination oral contraceptive containing EE and LNG and was well tolerated. 相似文献99.
Strome EM Wheler GH Higley JD Loriaux DL Suomi SJ Doudet DJ 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(24):15749-15754
Corticotropin-releasing factor (CRF) is a neuropeptide involved in integrating the behavioral, autonomic, and hormonal responses to stress within the central nervous system. Patients suffering from depression have abnormal activity in stress responsive brain regions and elevated cerebrospinal fluid CRF. The DSM-IV criteria for major depressive disorder include behavioral changes such as depressed mood, anhedonia, and psychomotor agitation/retardation. We studied the effects of 434 microgram of CRF given intracerebroventricularly over 40 min in group and individually housed monkeys to examine the role of elevated levels of central CRF on behavior. CRF elicited a wide range of behaviors, which fell into three broad categories: anxiety-like, depressive-like, and externally oriented. Externally oriented behaviors decreased, and anxiety-like behaviors increased regardless of how the animals were housed. Interestingly, increased depressive-like behaviors were only observed when the animals were socially housed. In a separate experiment, we examined the effects of the same dose of CRF on the regional cerebral glucose metabolism of lightly anesthetized monkeys by using positron emission tomography and [(18)F]fluorodeoxyglucose. CRF infusion increased glucose metabolism in the pituitary/infundibulum, the amygdala, and hippocampus. These results indicate that increased central CRF tone affects primate behavior in a context-dependent manner, and that it activates limbic and stress-responsive regions. The fact that intracerebroventricular CRF increases depressive-like behavior in socially housed animals and increases activity in limbic brain regions may help explain the behavioral and metabolic alterations in humans with affective disorders, and this model could therefore have significant value in the development of novel antidepressant treatments. 相似文献
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Acutely ill hospitalized medical patients are at high risk of venous thromboembolism (VTE). Although thromboprophylaxis in these patients is recommended since 2004 by the American College of Chest Physicians, it is widely underused. The doubt as to whether or not to treat patients at high VTE risk after hospital discharge came from the knowledge that this risk may persist after the hospital admission period. Two meta-analyses comparing extended- versus short-duration prophylaxis are published. The results demonstrate an unfavorable balance between VTE prevention and incidence of major bleeding in patients assigned to extended-duration thromboprophylaxis. Only in the APEX study, betrixaban, a direct inhibitor of factor Xa, shows similar efficacy and safety compared to enoxaparin. However, while it is very promising, oral anticoagulant phase III studies and post-marketing registers are lacking. Moreover, betrixaban has a long half-life, an excretion in the gut by means of P-glycoprotein, and the lack of an antidote. These characteristics and the meta-analysis results prompt us to answer no to the extended thromboprophylaxis in hospitalized medical patients, at least now. 相似文献