全文获取类型
收费全文 | 223714篇 |
免费 | 5137篇 |
国内免费 | 125篇 |
专业分类
耳鼻咽喉 | 1526篇 |
儿科学 | 8499篇 |
妇产科学 | 4585篇 |
基础医学 | 23190篇 |
口腔科学 | 2282篇 |
临床医学 | 18497篇 |
内科学 | 40244篇 |
皮肤病学 | 1457篇 |
神经病学 | 21040篇 |
特种医学 | 10059篇 |
外科学 | 34238篇 |
综合类 | 3205篇 |
一般理论 | 75篇 |
预防医学 | 23832篇 |
眼科学 | 3553篇 |
药学 | 12568篇 |
中国医学 | 694篇 |
肿瘤学 | 19432篇 |
出版年
2023年 | 347篇 |
2022年 | 573篇 |
2021年 | 1214篇 |
2020年 | 771篇 |
2019年 | 1256篇 |
2018年 | 23078篇 |
2017年 | 18182篇 |
2016年 | 20414篇 |
2015年 | 1997篇 |
2014年 | 2362篇 |
2013年 | 3102篇 |
2012年 | 10276篇 |
2011年 | 24365篇 |
2010年 | 20574篇 |
2009年 | 13079篇 |
2008年 | 22163篇 |
2007年 | 24566篇 |
2006年 | 3436篇 |
2005年 | 4984篇 |
2004年 | 5878篇 |
2003年 | 6687篇 |
2002年 | 4731篇 |
2001年 | 1070篇 |
2000年 | 1197篇 |
1999年 | 909篇 |
1998年 | 750篇 |
1997年 | 681篇 |
1996年 | 521篇 |
1995年 | 482篇 |
1994年 | 406篇 |
1993年 | 398篇 |
1992年 | 574篇 |
1991年 | 647篇 |
1990年 | 629篇 |
1989年 | 544篇 |
1988年 | 477篇 |
1987年 | 457篇 |
1986年 | 416篇 |
1985年 | 405篇 |
1984年 | 352篇 |
1983年 | 309篇 |
1982年 | 225篇 |
1981年 | 186篇 |
1980年 | 200篇 |
1979年 | 227篇 |
1978年 | 188篇 |
1977年 | 175篇 |
1974年 | 215篇 |
1973年 | 181篇 |
1970年 | 162篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
杨娅 Thomas Bartel Loredana Latina Guido Caspari 王新房 Raimund Erbel 《华中科技大学学报(医学英德文版)》2002,22(2):158-163
Coronary flow reserve (CFR) has been used toassess coronary microcirculation and epicardial coro-nary stenoses[1— 3 ] . CFR is defined as the ratio ofcoronary flow under maximal coronary vasodilatationto coronary flow under resting conditions[4 ] .Whenthe cross- sectional area of epicardial coronary arteriesis constant,coronary flow velocity (CFV) ratios areequal to volume flow ratios.The most common method used clinically formeasuring CFVR is intracoronary Doppler flow(ICD) analysis re… 相似文献
52.
53.
54.
55.
Elizabeth Campbell Ph.D. Danna Peterkin R.N. Richard Abbott M.B. B.S. John Rogers M.B. B.S. 《Preventive medicine》1997,26(6):801-807
Background.Computers that collect data from patients and provide both patients and practitioners with printed feedback on a range of health risks are a tool for assisting general practitioners with preventive care. This study assessed the impact of computer-generated printed feedback on cervical screening among women who were underscreened for cervical cancer.Method.Female attenders at two Australian general practices were randomly allocated to Experimental or Control groups. Women in both groups completed a health risk survey on a touch screen computer prior to their consultation. Those in the Experimental group received printed pages summarizing their results, including their eligibility for cervical screening and last Pap test, for themselves and their doctor. The number and proportion of underscreened women who had a Pap test in the 6 months after completing the computer survey, as determined by pathology records, were examined.Results.Of the 679 participants, 139 were classified as underscreened on the basis of self-report (74 Experimental, 65 Control) and 272 on the basis of their pathology records (148 Experimental, 124 Control). Overall about one-third of women had a test in the 6-month period, and the differences between the groups were not significant for women overall (18–70 years) or for women 18–49 years. Among women 50–70 who were underscreened based on self-report, those receiving the printout were more likely to have a Pap test in the next 6 months (P< 0.05). This pattern was also evident, but did not reach statistical significance, for older women who were underscreened based on pathology records.Conclusions.We are unable to draw conclusions regarding the effectiveness of the computer system due to the modest proportions of women screened, the small numbers, and the fact that the computer survey may have created an intervention effect in the Control group. As the study suggests the computer system is acceptable to women and may be effective for encouraging screening among older women, further exploration of the system is desirable. 相似文献
56.
57.
58.
Fran ois X. Roux M.D. Serge Mordon Ph.D. Catherine Fallet-Bianco M.D. Louis Merienne M.D. Bertrand C. Devaux M.D. Jean-Paul Chodkiewicz M.D. 《Surgical neurology》1990,34(6):402-407
Considering that the 1.32-μm Nd-YAG laser should have physicothermal properties close to those of the CO2 laser, a series of experiments were conducted on rat cortex (N = 51). Three laser wavelengths were compared: CO2 laser (10.6 μm), 1.06-μm Nd-YAG, and 1.32-μm Nd-YAG lasers. For each shot, temperature measurements were recorded with an infrared thermographic videocamera. The digitized signals were figured as thermal profiles and temperature developments. Ninety-five shots were correctly studied and analyzed: CO2, N = 29; 1.06-μm Nd-YAG, N = 20; 1.32-μm Nd-YAG, N = 46. The histological lesions produced by these three lasers were compared on animals killed 24 hours (N = 20), 8 days (N = 20), and 30 days (N = 5) after the laser impacts. For equivalent densities of energy, the depth of cortical necrosis was comparable for the CO2 laser (200–250 μm) and the 1.32-μm Nd-YAG laser (210–260μm) whatever the date of death; the 1.06-μm Nd-YAG laser shots were responsible for much more important damage (400–550μm). Because of its important absorption in water and nervous tissue, the authors consider the 1.32-μm Nd-YAG laser most suitable for neurosurgery, particularly because it is conducted through optic fibers, and therefore is easy to handle during neurosurgical procedures. 相似文献
59.
60.
H L Elliott P A Meredith L Campbell J L Reid 《Clinical pharmacology and therapeutics》1988,43(5):554-560
An exaggerated fall in blood pressure has been reported with the combination of an alpha 1-blocker and a calcium antagonist. This study investigated, in a placebo-controlled, randomized crossover trial, the clinical usefulness of the combination of prazosin (2 mg b.i.d.) and verapamil (160 mg b.i.d.). Therapeutic efficacy was monitored at regular outpatient visits: average supine and erect blood pressures were, respectively, 175/99 and 176/103 mm Hg with placebo, 160/91 and 164/96 mm Hg with single drug treatment, and 152/84 and 152/89 mm Hg with combination therapy. This significant and clinically useful reduction in blood pressure had an overall magnitude of approximately 28/18 mm Hg (supine) and 29/19 mm Hg (erect). Further measurements were made during a series of intensive study days, and the most important additional finding was a pharmacokinetic interaction that resulted in increased peak concentrations and bioavailability of prazosin. In conclusion, the combination of prazosin and verapamil proved effective in the treatment of 12 patients with essential hypertension who had been poorly responsive to conventional treatment with a beta-blocker and thiazide diuretic. 相似文献