全文获取类型
收费全文 | 14228篇 |
免费 | 823篇 |
国内免费 | 492篇 |
专业分类
耳鼻咽喉 | 47篇 |
儿科学 | 164篇 |
妇产科学 | 90篇 |
基础医学 | 439篇 |
口腔科学 | 49篇 |
临床医学 | 1556篇 |
内科学 | 1846篇 |
皮肤病学 | 59篇 |
神经病学 | 319篇 |
特种医学 | 342篇 |
外国民族医学 | 1篇 |
外科学 | 3009篇 |
综合类 | 1621篇 |
一般理论 | 1篇 |
预防医学 | 1151篇 |
眼科学 | 91篇 |
药学 | 2688篇 |
12篇 | |
中国医学 | 530篇 |
肿瘤学 | 1528篇 |
出版年
2024年 | 36篇 |
2023年 | 183篇 |
2022年 | 406篇 |
2021年 | 454篇 |
2020年 | 475篇 |
2019年 | 371篇 |
2018年 | 421篇 |
2017年 | 401篇 |
2016年 | 447篇 |
2015年 | 415篇 |
2014年 | 943篇 |
2013年 | 903篇 |
2012年 | 855篇 |
2011年 | 936篇 |
2010年 | 767篇 |
2009年 | 797篇 |
2008年 | 805篇 |
2007年 | 812篇 |
2006年 | 677篇 |
2005年 | 563篇 |
2004年 | 444篇 |
2003年 | 428篇 |
2002年 | 319篇 |
2001年 | 304篇 |
2000年 | 218篇 |
1999年 | 204篇 |
1998年 | 186篇 |
1997年 | 157篇 |
1996年 | 161篇 |
1995年 | 147篇 |
1994年 | 140篇 |
1993年 | 78篇 |
1992年 | 109篇 |
1991年 | 87篇 |
1990年 | 83篇 |
1989年 | 74篇 |
1988年 | 55篇 |
1987年 | 64篇 |
1986年 | 74篇 |
1985年 | 88篇 |
1984年 | 96篇 |
1983年 | 36篇 |
1982年 | 55篇 |
1981年 | 44篇 |
1980年 | 38篇 |
1979年 | 30篇 |
1978年 | 33篇 |
1977年 | 30篇 |
1976年 | 34篇 |
1975年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
Plasma concentrations and bioavailability of propranolol by oral, rectal, and intravenous administration in man 总被引:2,自引:0,他引:2
E Cid F Mella L Lucchini M Cárcamo J Monasterio 《Biopharmaceutics & drug disposition》1986,7(6):559-566
Eight normal male volunteers received 80 mg doses of propranolol by the oral and rectal routes and 2.2 mg by intravenous administration in a crossover fashion. Plasma concentrations of propranolol were measured by a gas chromatographic method using an electron capture detector. Individual subject concentration-time data were analysed and results indicated that the data fit a two compartment model with first order absorption. An approximately two-fold higher plasma propranolol concentration was observed after rectal administration as compared with oral dosing. Statistical analysis of the difference in the total AUCs indicates a significantly higher bioavailability of propranolol administered by the rectal route. The reduced bioavailability after oral administration indicates a substantial first pass effect but that it is possible to bypass the liver, at least partially, by giving the drug rectally to man. 相似文献
43.
反映手术间利用效率的统计指标与方法探讨 总被引:1,自引:0,他引:1
目的 探索反映手术室工作状态的指标和方法,为了解科室需求、合理利用手术室资源奠定基础。方法 提取医院局域网中有关手术安排、手术过程、麻醉等信息,通过常用统计指标、统计图表,反映手术室、手术科室、手术间的工作状态。结果 工作日手术问日均工作6.34小时,节假日日均工作0.6l小时。工作日13点后有近l/3的空台,14点后近l/2空台。个别手术间利用率偏低。结论 1.由在用手术间时点统计结果可见,14点后接台手术尚有一定潜力,节假日安排手术潜力更大;2.工作日间均工作时数已近满负荷,若要进一步提高手术间的利用,需加强麻醉科和手术室力量。 相似文献
44.
Dr. Shosaku Nakahara M.D. Hideaki Itoh M.D. Ryuichi Mibu M.D. Shinichi Ikeda M.D. Yoshihiro Oohata M.D. Kamesaburo Kitano M.D. Yoshihiko Nakamura M.D. 《Diseases of the colon and rectum》1988,31(10):762-766
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line,
using an EEA™ stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following
surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients
could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure
and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct
tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily
by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation
is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is
a functionally acceptable option for low rectal cancer. 相似文献
45.
46.
本文通过对医院药事管理委员会的组织形式以及在医院药学事业中的特殊地位、工作任务、工作职责及职能效应的初步探讨,指出医院药事管理委员会在发展和建设医院药学事业中具有十三种职能、七大效应。认为加强医院药事管理委员会建设,是发展医院药学事业和保证医院药品质量的一种好方式。 相似文献
47.
The effects of withdrawal from continuous administration of cocaine on behavioral sensitivity to apomorphine and monoamine receptor density were examined in rats. Subdermal minipumps that delivered either saline or 20 mg/kg/day cocaine hydrochloride were implanted for 2 weeks. Apomorphine-induced stereotypy (0.5 mg/kg, SC) was examined in separate groups of rats either 4 hr or 7, 28, or 60 days after removal of the minipumps. Transient enhanced sensitivity to apomorphine-induced stereotypy occurred during the course of withdrawal. Animals withdrawn from cocaine for 4 hours did not differ from controls in their sensitivity to apomorphine, whereas animals withdrawn from cocaine for 7 days exhibited an increase in apomorphine-induced oral stereotypy relative to controls. However, the enhanced stereotypy response was no longer evident in animals withdrawn for 28–60 days. The animals were sacrificed after behavioral testing, and their brains were assayed for changes in monoamine receptor density in the frontal cortex, caudate-putamen, and nucleus accumbens. The density of 3H-SCH-23390-labeled D1 receptors was altered in all three regions examined in a time-dependent manner that paralleled the changes in behavioral sensitivity to apomorphine. There was a transient decrease in D1 receptor density that was evident by 7 days following withdrawal from continuous cocaine administration and was no longer evident 28 or 60 days posttreatment. There were no changes in 3H-spiroperidol-labeled D2 receptors, 125-pindolol-labeled β-adrenergic receptors, or 3H-ketanserin-labeled 5-HT2 receptors in any of the regions examined at both 4 hr and 7 days after termination of the cocaine infusion. These findings are discussed in terms of their relevance to developing pharmacologic treatments for withdrawal from cocaine. © 1994 Wiley-Liss, Inc. 相似文献
48.
49.
渗透压微泵恒速给药丙戊酸在小鼠体内的时间药物动力学 总被引:1,自引:0,他引:1
以渗透压微泵植入小鼠皮下恒速给予丙戊酸钠,在达到理论稳态浓度时间后,血浆药浓呈昼夜变化,白昼高于夜间,峰值位于明期末。药动学研究揭示丙戊酸血药浓度的昼夜差异可能与其清除率及分布容积的昼夜变化有关。 相似文献
50.
OBJECTIVE: Circumferential resection margin (CRM) involvement has been correlated with a high risk of developing local recurrence. The aim of this study was to examine the prognostic significance of the CRM involvement after curative resection of rectal cancer in patients treated with preoperative radiotherapy and postoperative chemotherapy where indicated. METHOD: All patients with rectal cancer treated in a regional central unit from 1996 to 2004 were identified. A surgical resection was performed on 257 patients, and in 229 of these this was assessed as potentially curative. The CRM was examined in all patients. A CRM of < or = 1 mm was considered positive. RESULTS: A positive margin was seen in 19 (8%) patients. At a median follow up of 40 months, only four (1.7%) patients had developed local recurrence, one of whom had a positive CRM. In the four patients the tumour was 5 cm or less from the anal verge. There were no significant differences regarding local recurrence and survival between CRM positive and negative tumours. CONCLUSION: Rectal cancer managed by combined radiochemotherapy and surgery resulted in a low positive CRM rate and a low local recurrence rate. An involved CRM was not a predictor of local recurrence. 相似文献