全文获取类型
收费全文 | 1075024篇 |
免费 | 71785篇 |
国内免费 | 1371篇 |
专业分类
耳鼻咽喉 | 15016篇 |
儿科学 | 34609篇 |
妇产科学 | 28631篇 |
基础医学 | 153437篇 |
口腔科学 | 29561篇 |
临床医学 | 94921篇 |
内科学 | 203720篇 |
皮肤病学 | 24391篇 |
神经病学 | 81457篇 |
特种医学 | 42981篇 |
外国民族医学 | 201篇 |
外科学 | 163142篇 |
综合类 | 21702篇 |
现状与发展 | 1篇 |
一般理论 | 263篇 |
预防医学 | 74615篇 |
眼科学 | 24535篇 |
药学 | 86117篇 |
7篇 | |
中国医学 | 2807篇 |
肿瘤学 | 66066篇 |
出版年
2019年 | 7760篇 |
2018年 | 11298篇 |
2017年 | 8912篇 |
2016年 | 10101篇 |
2015年 | 11268篇 |
2014年 | 15274篇 |
2013年 | 22206篇 |
2012年 | 30551篇 |
2011年 | 32293篇 |
2010年 | 18956篇 |
2009年 | 17815篇 |
2008年 | 29954篇 |
2007年 | 32072篇 |
2006年 | 32715篇 |
2005年 | 31043篇 |
2004年 | 29731篇 |
2003年 | 28568篇 |
2002年 | 27540篇 |
2001年 | 60027篇 |
2000年 | 61487篇 |
1999年 | 50935篇 |
1998年 | 12451篇 |
1997年 | 11000篇 |
1996年 | 11015篇 |
1995年 | 10326篇 |
1994年 | 9343篇 |
1993年 | 8860篇 |
1992年 | 37793篇 |
1991年 | 36278篇 |
1990年 | 35755篇 |
1989年 | 34295篇 |
1988年 | 30872篇 |
1987年 | 29988篇 |
1986年 | 28219篇 |
1985年 | 26451篇 |
1984年 | 19189篇 |
1983年 | 16117篇 |
1982年 | 8825篇 |
1979年 | 17032篇 |
1978年 | 11405篇 |
1977年 | 10230篇 |
1976年 | 8837篇 |
1975年 | 10071篇 |
1974年 | 11658篇 |
1973年 | 11278篇 |
1972年 | 10757篇 |
1971年 | 10093篇 |
1970年 | 9253篇 |
1969年 | 8939篇 |
1968年 | 7917篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Trazodone hydrochloride is an oral antidepressant agent which has been associated with the improvement of erections in impotent men and the development of prolonged erections or priapism in potent men. An in vivo study in animal and human subjects was performed to gain experience with the effect of intracavernosal trazodone. In the anesthetized New Zealand White rabbit, intracavernosal trazodone or its major metabolite m-chlorophenylpiperazine (m-CPP) produced full penile erection in 76% and 84% of animals studied respectively with doses ranging from one to 15 mg. On the other hand, intracavernosal administration of five mg. papaverine resulted in a prolonged erection in 90% of animals studied. In 13 selected volunteer patients, intracavernosal trazodone caused tumescence but not full penile erection with corporal body pressures of 28.2 +/- 5.8 mm. Hg. Intracavernosal papaverine or papaverine and phentolamine in these subjects resulted in significantly higher corporal body pressures of 58 +/- 18 mm. Hg (p less than .05). Intracavernosal administration of alpha adrenoceptor agonists but not normal saline resulted in complete detumescence of trazodone- or m-CPP-induced prolonged erection in the animal studies. Intracavernosal trazodone results in erectile activity that appears in part based on its local alpha blocking activity but like other intracavernosal alpha-blocking agents is not as effective in initiating penile erections as are intracavernosal agents that directly induce smooth muscle relaxation. 相似文献
993.
994.
995.
Anti-estradiol immunoperoxidase labeling of nuclei, not cytoplasm, in paraffin sections, determines estrogen receptor status of breast cancer 总被引:1,自引:0,他引:1
J C O'Keane E Okon K Moroz B Burke K Sheahan M J O'Brien 《The American journal of surgical pathology》1990,14(2):121-127
We evaluated a commercially available polyclonal antibody to 17 beta-estradiol as the basis for an estrogen receptor (ER) assay of breast carcinoma in formalin-fixed paraffin tissues and then compared it with both the ER-ICA antibody in serial paraffin sections and the biochemical assay of corresponding fresh tissue. Using the estradiol antibody, 49 of 50 cases showed some cytoplasmic staining; 38 cases had nuclear staining. Sensitivity and specificity for different proportions of positive nuclear and cytoplasmic staining were calculated using receiver-operator characteristic curves. The optimum correlation with the biochemical assay was obtained with nuclear staining alone. Greater than 30% nuclear positivity as a cut-off point yielded a sensitivity of 76% and a specificity of 82%. The corresponding ER-ICA values in 38 cases yielded a sensitivity of 93% and a specificity of 56%. The methodology for the ER-ICA assay was more technically demanding in paraffin sections than that of the estradiol antibody and considerably more expensive. This study is the first to show that with nuclear staining only, and not cytoplasmic staining, as the parameter of positivity, the immunocytochemical assay of ER with anti-17 beta-estradiol antibody in routinely processed, formalin-fixed, archival material is an accurate and specific method for the determination of the ER status of breast carcinoma. 相似文献
996.
997.
K Teranishi M Murase M Maeda Y Tomida T Koyama H Sasa T Sone H Tsuboi K Kawaguchi 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(11):901-903
A case of Beh?et disease associated with aortic valve regurgitation treated with aortic valve replacement is reported. The patient was treated successfully with special surgical techniques for prevention of post operative paravalvular leakage and occurrence of pseudo aneurysm because the patient was under long-term steroid therapy for Beh?et disease. 相似文献
998.
Alteration in the function of cerebral neurotransmitter receptors during the establishment of alcohol dependence: neurochemical aspects 总被引:1,自引:1,他引:0
Chronic alcohol treatment induces a variety of effects on the metabolism of neurotransmitters and the function of their receptors. Recent studies on alcohol dependence and/or functional tolerance to alcohol have clearly demonstrated that neurotransmitter-gated and receptor-coupled ion channels, as well as neurotransmitter receptor coupled with intracellular mediator systems, such as phosphatidylinositides and cyclic nucleotide-generating systems, are invariably suppressed during alcohol dependence. Future studies on the central actions of alcohol and on alcohol dependence should therefore be directed at the molecular changes in synaptic membrane-bound components such as neurotransmitter receptors, as well as on neurotransmitter release and relevant membrane-bound enzymes. 相似文献
999.
1000.