全文获取类型
收费全文 | 916篇 |
免费 | 61篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 17篇 |
妇产科学 | 14篇 |
基础医学 | 76篇 |
口腔科学 | 8篇 |
临床医学 | 67篇 |
内科学 | 149篇 |
皮肤病学 | 2篇 |
神经病学 | 40篇 |
特种医学 | 94篇 |
外科学 | 280篇 |
综合类 | 13篇 |
预防医学 | 61篇 |
眼科学 | 21篇 |
药学 | 63篇 |
中国医学 | 1篇 |
肿瘤学 | 114篇 |
出版年
2023年 | 6篇 |
2022年 | 5篇 |
2021年 | 10篇 |
2020年 | 8篇 |
2019年 | 8篇 |
2018年 | 24篇 |
2017年 | 12篇 |
2016年 | 17篇 |
2015年 | 19篇 |
2014年 | 25篇 |
2013年 | 27篇 |
2012年 | 57篇 |
2011年 | 35篇 |
2010年 | 36篇 |
2009年 | 34篇 |
2008年 | 31篇 |
2007年 | 61篇 |
2006年 | 36篇 |
2005年 | 36篇 |
2004年 | 17篇 |
2003年 | 29篇 |
2002年 | 28篇 |
2001年 | 27篇 |
2000年 | 27篇 |
1999年 | 26篇 |
1998年 | 27篇 |
1997年 | 14篇 |
1996年 | 12篇 |
1995年 | 10篇 |
1994年 | 12篇 |
1993年 | 8篇 |
1992年 | 23篇 |
1991年 | 18篇 |
1990年 | 27篇 |
1989年 | 33篇 |
1988年 | 28篇 |
1987年 | 12篇 |
1986年 | 18篇 |
1985年 | 15篇 |
1984年 | 9篇 |
1983年 | 12篇 |
1982年 | 17篇 |
1981年 | 6篇 |
1980年 | 8篇 |
1979年 | 11篇 |
1978年 | 12篇 |
1977年 | 11篇 |
1976年 | 12篇 |
1975年 | 8篇 |
1973年 | 4篇 |
排序方式: 共有1022条查询结果,搜索用时 15 毫秒
1.
外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响. 相似文献
2.
J N Kvale W R Gillanders T F Buss C R Hofstetter D Gemmel 《The Journal of the American Board of Family Practice / American Board of Family Practice》1990,3(4):231-239
Providing health care for independent-living elderly persons is important, yet family physicians often lack accurate information about needs and access to care. The Community-Oriented Primary Care (COPC) approach and health status models from health services research provide a framework for assessing need and access to care. Personal interviews were conducted with 990 noninstitutionalized elderly persons in Youngstown, Ohio. Results showed that poverty, gender, and race were not strongly related to health status as measured by numbers of symptoms, functional status, or subjective health status. In addition, elderly persons had fewer health care needs and greater access to care than expected. Simple models of health status, need, and access do not seem to apply. The study shows the usefulness of COPC in planning health services; however, more effort is needed to refine measures of health status, need, and access. 相似文献
3.
取代四氢异喹啉衍生物的合成及其生物活性 总被引:7,自引:0,他引:7
粉防己碱有钙拮抗作用,临床试用于治疗高血压,其裂解产物钙拮抗作用降低,但有α-肾上腺素能受体拮抗作用,本文以裂解物为先导化合物设计合成了两类取代的四氢异喹啉衍生物Ⅲ及Ⅳ。初步药理试验表明:大部分化合物有α-肾上腺素能受体拮抗作用,少数化合物钙拮抗活性有所增强,其中Ⅲ15,19对正常麻醉大鼠有一定的降压作用、Ⅳ17,19对实验性动物心律失常有明显的保护作用。部分化合物量化计算表明:化合物与α1-受体作用方式可能是形成电荷转移复合物。 相似文献
4.
5.
6.
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
7.
8.
14 patients with radiologically documented vesicorenal reflux (5 bilateral, 7 unilateral, 2 unilateral double-J stents) received intravesical immunotherapy with bacillus Calmette-Guérin (BCG) after treatment of their superficial urothelial tumors. 1 patient with a double-J stent suffered a highly febrile attack following obstruction of the indwelling ureteral catheter. The other patients tolerated 1 or 2 (6 of 14 patients) courses of BCG without an increase in side effects. Topical intravesical therapy with BCG in patients with vesicorenal reflux seems to be indicated in view of the multicentricity of urothelial carcinoma and can be performed without an increased risk of complications. 相似文献
9.
10.
D. Lang G. G. Belz R. Hofstetter U. Töllner G. von Bernuth 《Journal of molecular medicine (Berlin, Germany)》1976,54(8):389-390
Summary Serum digoxin concentration and half-life were radioimmunologically determined in 9 mature newborns after 7 days medication with digoxin. The newborns were in respiratory distress treated with continuous positive airway pressure or were suspected to have serious congenital heart disease. Loading dose was 26 µg/kg body weight intravenously and 35 µg/kg body weight orally, respectively. Maintenance dose corresponded to 1/8th of the digitalization dose twice daily.The serum digoxin level 12 h after the last dose varied between 1.4 and 2.5 ng/ml (mean 2.0 ng/ml, Sx=0.4). The serum half-life of digoxin varied between 21.7 and 42.4 h (mean 30.0 h, Sx=7.7). The mean serum half-life of digoxin of 30 h attained values found in adults without renal disease. This suggests that the serum digoxin levels of newborns which are usually higher if compared with those of adults result from higher digoxin doses per unit body weight and not from diminished digoxin elimination. 相似文献