全文获取类型
收费全文 | 5031篇 |
免费 | 377篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 54篇 |
儿科学 | 95篇 |
妇产科学 | 54篇 |
基础医学 | 699篇 |
口腔科学 | 187篇 |
临床医学 | 458篇 |
内科学 | 785篇 |
皮肤病学 | 52篇 |
神经病学 | 726篇 |
特种医学 | 157篇 |
外科学 | 576篇 |
综合类 | 64篇 |
一般理论 | 33篇 |
预防医学 | 478篇 |
眼科学 | 100篇 |
药学 | 601篇 |
中国医学 | 11篇 |
肿瘤学 | 287篇 |
出版年
2023年 | 29篇 |
2022年 | 60篇 |
2021年 | 128篇 |
2020年 | 84篇 |
2019年 | 113篇 |
2018年 | 124篇 |
2017年 | 76篇 |
2016年 | 129篇 |
2015年 | 142篇 |
2014年 | 171篇 |
2013年 | 246篇 |
2012年 | 378篇 |
2011年 | 348篇 |
2010年 | 209篇 |
2009年 | 177篇 |
2008年 | 311篇 |
2007年 | 322篇 |
2006年 | 321篇 |
2005年 | 294篇 |
2004年 | 305篇 |
2003年 | 271篇 |
2002年 | 269篇 |
2001年 | 71篇 |
2000年 | 37篇 |
1999年 | 50篇 |
1998年 | 77篇 |
1997年 | 55篇 |
1996年 | 46篇 |
1995年 | 43篇 |
1994年 | 45篇 |
1993年 | 38篇 |
1992年 | 36篇 |
1991年 | 27篇 |
1990年 | 25篇 |
1989年 | 23篇 |
1988年 | 20篇 |
1987年 | 30篇 |
1986年 | 21篇 |
1985年 | 21篇 |
1984年 | 22篇 |
1983年 | 13篇 |
1982年 | 21篇 |
1981年 | 27篇 |
1980年 | 19篇 |
1979年 | 13篇 |
1978年 | 13篇 |
1977年 | 11篇 |
1976年 | 10篇 |
1975年 | 8篇 |
1972年 | 8篇 |
排序方式: 共有5417条查询结果,搜索用时 15 毫秒
71.
Benjamin P. Haynes Michael Jarman Mitchell Dowsett Anshumala Mehta Per E. Lønning Leslie J. Griggs Alison Jones Trevor Powles Rob Stein R. Charles Coombes 《Cancer chemotherapy and pharmacology》1991,27(5):367-372
Summary The pyridylglutarimide 3-ethyl-3-(4-pyridyl)-piperidine-2,6-dione (PyG) is a novel inhibitor of aromatase that was shown to cause effective suppression of plasma oestradiol levels in postmenopausal patients. In four patients receiving oral doses of PyG (500 mg) twice daily for 3–4 days, oestradiol levels fell to 31.1%±6.3% of baseline values within 48 h and remained suppressed during treatment. Of a further six patients who received oral PyG (1 g) as a single dose, five had quantifiable oestradiol levels. Oestradiol suppression was sustained for 36 h and recovery correlated with a fall of PyG concentrations below a threshold value of ca. 2 g/ml. The pharmacokinetics of PyG were non-linear and, when fitted to the integrated Michaelis-Menten equation, yielded good parameter estimates forC
o (21.7±1.82 g/ml),K
m (2.66±0.68 g/ml) and Vmax (0.86±0.06 g ml–1 h–1). On subsequent repeated dosing with PyG, both theK
m (4.31±0.48 g/ml) and the Vmax (1.83±0.13 g ml–1 h–1) values increased and recovery from oestradiol suppression was more rapid, indicating that PyG induces its own metabolism.Abbreviations PyG
3-ethyl-3-(4-pyridyl)piperidine-2,6-dione
- AG
aminoglutethimide
- CSCC
cholesterol side-chain cleavage
- HPLC
high-performance liquid chromatography
- AUC
area under the concentration versus time curve
This study was supported in part by grants to the Institute of Cancer Research (Royal Cancer Hospital) from the Cancer Research Campaign and Medical Research Council 相似文献
72.
David W Cadotte Bin Xu Ronald J Racine Glenda M MacQueen Jun Feng Wang Bruce McEwen L Trevor Young 《Neuropsychopharmacology》2003,28(8):1448-1453
Lithium remains the gold standard in the treatment of bipolar disorder. Long-term treatment with lithium may lead to specific adaptational changes in gene expression that contribute to a neuroprotective effect. In this study, the pilocarpine model of spontaneous limbic epilepsy was used to induce mossy fiber sprouting (axonal growth of the dentate granule cells that synapse on the pyramidal cells of the CA3 region) to examine the prophylactic neuroprotective effects of lithium in vivo. There were four groups of animals: pilocarpine treated (Pil+/Li-); pilocarpine treated followed by lithium (Pil+/Li+); lithium alone (Pil-/Li+); control (Pil-/Li-). Timm staining was used to obtain density measurements in the stratum oriens and the inner molecular layer of the hippocampus. Mossy fiber density was higher in the pilocarpine-treated animals compared to controls. Chronic lithium following pilocarpine treatment attenuated the density of mossy fibers but lithium alone had no effect. No changes in hilar volume or neuronal number were detected using stereological procedures. The ability of lithium to attenuate activation-induced reorganization in the hippocampus provides evidence for its role as a neuroprotective agent in an in vivo model that may be relevant to its clinical effects in bipolar disorder. 相似文献
73.
74.
75.
76.
77.
Carl N Sprung Michael Chao Trevor Leong Michael J McKay 《Clinical cancer research》2005,11(17):6352-6358
PURPOSE: Despite its prominent contribution to cancer cure and palliation, around 1% to 5% of cancer patients suffer serious side effects from radiotherapy. A cardinal goal in the fields of radiobiology and oncology is to predict normal tissue radiosensitivity of a cancer patient before radiotherapy. Higher tumor control rates are likely if radiotherapy individualization could be achieved by applying predictive approaches. EXPERIMENTAL DESIGN: Here, we make use of the cytokinesis block micronucleus assay to assess radiosensitivity in cell lines derived from two different cell lineages obtained from clinically radiosensitive patients. We determined the micronucleus frequency after graded doses of ionizing radiation to primary fibroblasts and lymphoblast cell lines derived from 36 highly radiosensitive cancer patients. RESULTS: Many cell lines, following exposure to ionizing radiation, from patients with severe clinical reactions to radiotherapy showed statistically significantly higher frequencies of micronuclei than those from patients who had normal reactions to radiotherapy. One individual revealed significantly higher micronucleus frequencies in both cell lineages. Interestingly, lymphoblast cell lines from one patient showed micronucleus frequencies similar to ataxia telangiectasia mutated-deficient cells. CONCLUSIONS: These results indicate that the micronucleus assay may have use for identifying predisposition to clinical radiosensitivity, at least in a subset of patients as a component of a pretreatment radiosensitivity assay for use in the clinic. 相似文献
78.
79.
Trevor W Lambert Fay Smith Michael J Goldacre 《The British journal of general practice》2016,66(652):e848-e857
BackgroundThere are more studies of current job satisfaction among GPs than of their views about their future career prospects, although both are relevant to commitment to careers in general practice.AimTo report on the views of GPs compared with clinicians in other specialties about their future career prospects.MethodQuestionnaires were sent to the doctors at different times after graduation, ranging from 3 to 24 years.ResultsBased on the latest survey of each graduation year of the 20 940 responders, 66.2% of GPs and 74.2% of hospital doctors were positive about their prospects and 9.7% and 8.3%, respectively, were negative. However, with increasing time since graduation and increasing levels of seniority, GPs became less positive about their prospects; by contrast, over time, surgeons became more positive. Three to 5 years after graduation, 86.3% of those training in general practice were positive about their prospects compared with 52.9% of surgical trainees: in surveys conducted 12–24 years after graduation, 60.2% of GPs and 76.6% of surgeons were positive about their prospects.ConclusionGPs held broadly positive views of their career prospects, as did other doctors. However, there was an increase in negativity with increasing time since graduation that was not seen in hospital doctors. Research into the causes of this negativity and policy measures to ameliorate it would contribute to the continued commitment of GPs and may help to reduce attrition. 相似文献
80.