全文获取类型
收费全文 | 25813篇 |
免费 | 1301篇 |
国内免费 | 66篇 |
专业分类
耳鼻咽喉 | 365篇 |
儿科学 | 2031篇 |
妇产科学 | 611篇 |
基础医学 | 2951篇 |
口腔科学 | 456篇 |
临床医学 | 1409篇 |
内科学 | 4779篇 |
皮肤病学 | 987篇 |
神经病学 | 1141篇 |
特种医学 | 953篇 |
外科学 | 3866篇 |
综合类 | 920篇 |
一般理论 | 10篇 |
预防医学 | 1263篇 |
眼科学 | 1312篇 |
药学 | 2120篇 |
中国医学 | 144篇 |
肿瘤学 | 1862篇 |
出版年
2023年 | 146篇 |
2022年 | 377篇 |
2021年 | 726篇 |
2020年 | 407篇 |
2019年 | 473篇 |
2018年 | 683篇 |
2017年 | 449篇 |
2016年 | 661篇 |
2015年 | 585篇 |
2014年 | 913篇 |
2013年 | 1081篇 |
2012年 | 1527篇 |
2011年 | 1622篇 |
2010年 | 878篇 |
2009年 | 710篇 |
2008年 | 1235篇 |
2007年 | 1307篇 |
2006年 | 1123篇 |
2005年 | 1060篇 |
2004年 | 960篇 |
2003年 | 889篇 |
2002年 | 801篇 |
2001年 | 723篇 |
2000年 | 683篇 |
1999年 | 596篇 |
1998年 | 244篇 |
1997年 | 179篇 |
1996年 | 144篇 |
1995年 | 136篇 |
1994年 | 114篇 |
1993年 | 130篇 |
1992年 | 356篇 |
1991年 | 390篇 |
1990年 | 342篇 |
1989年 | 358篇 |
1988年 | 308篇 |
1987年 | 277篇 |
1986年 | 268篇 |
1985年 | 279篇 |
1984年 | 219篇 |
1983年 | 181篇 |
1979年 | 241篇 |
1978年 | 158篇 |
1977年 | 148篇 |
1976年 | 135篇 |
1975年 | 163篇 |
1974年 | 154篇 |
1973年 | 176篇 |
1972年 | 138篇 |
1971年 | 122篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
S P Hooker S F Figoni M M Rodgers R M Glaser T Mathews A G Suryaprasad S C Gupta 《Journal of rehabilitation research and development》1992,29(3):1-11
This study determined the metabolic and hemodynamic responses in eight spinal cord injured (SCI) quadriplegics (C5-C8/T1) performing subpeak arm crank exercise (ACE) alone, subpeak functional electrical stimulation leg cycle exercise (FES-LCE) alone, and subpeak FES-LCE concurrent with subpeak ACE (hybrid exercise). Subjects completed 10 minutes of each exercise mode during which steady-state oxygen uptake (VO2), pulmonary ventilation (VE), heart rate (HR), cardiac output (CO), stroke volume (SV), mean arterial pressure (MAP), arteriovenous oxygen difference (a-v O2 diff), and total peripheral resistance (TPR) were determined. Although mean VO2 for both ACE alone and FES-LCE alone was matched at 0.66 l/mi, individualized power outputs ranged from 0-30 W (mean = 19.4 +/- 1.3) and 0-12.2 W (mean = 2.3 +/- 0.6), respectively. Hybrid exercise elicited significantly higher VO2 (by 54 percent), VE (by 39-53 percent), HR (by 19-33 percent), and CO (by 33-47 percent), and significantly lower TPR (by 21-34 percent) than ACE or FES-LCE performed alone (P less than or equal to 0.05). Stroke volume was similar between hybrid exercise and FES-LCE alone, and these two exercise modes evoked a significantly higher SV (by 41-56 percent) than during ACE alone. These data clearly demonstrate that hybrid exercise creates a higher aerobic metabolic demand and cardiac-volume load in SCI quadriplegics than either subpeak levels of ACE or FES-LCE performed separately. Therefore, hybrid exercise may provide more advantageous central cardiovascular training effects in quadriplegics than either ACE or FES-LCE alone. 相似文献
42.
P Kumar S K Rastogi B N Gupta T Husain 《The Journal of the Society of Occupational Medicine》1991,41(4):157-160
Behavioural studies were conducted on a random sample of 38 glass bangle workers engaged in various occupations and exposed to high ambient temperature (38.2 +/- 3.4 degrees C) and radiant heat (46.2 +/- 5.1 degrees C) during their work in the glass bangle industries at Firozabad, India. Twenty-two control subjects of similar age and socio-economic status unexposed to heat during their work were also studied for comparison. The digit span test, digit symbol test, Bourdon-Wiersma vigilance test, flicker fusion test and Maudsley personality inventory (MPI) were used to assess the behavioural changes induced by the existing heat stress. The mean scores of immediate memory were much lower in the exposed population than in the controls thereby indicating impairment of immediate memory in the study group. The visuo-motor coordination and vigilance were also significantly affected. Visual perception showed a downward trend among the glass bangle workers, although the MPI test indicated no personality changes. 相似文献
43.
A study conducted in 1990 revealed that 2% (range 0.6-4.8) of negative blood smears were mislabelled as positive, and 6.7% of positive blood smears were mislabelled as negative. A result of such mislabelling would be inadequate treatment of a large number of patients. Hence the need to look into the training aspect and system of supervision of laboratory technicians. The present system of cross-checking of blood smears at different levels also needs to be reviewed. A study which could address itself to these needs is indicated. 相似文献
44.
45.
S K Gupta A K Abraham G K Mani K M Cherian J S Moorthy K Bhaskaran 《Japanese heart journal》1987,28(4):507-514
Three cases of chronic rheumatic heart disease with involvement of all four valves are presented. The involvement of tricuspid and pulmonary valves was suspected clinically and was confirmed by two-dimensional echo, Doppler, hemodynamic and angiographic findings. These findings were also verified surgically and histopathologically in 2 cases. One of the cases died after cardiac catheterization; the other 2 cases were treated surgically with success. 相似文献
46.
47.
48.
49.
To measure myelin basic protein (MBP)-like material in cerebrospinal fluid, we compared two radioimmunoassays, both using the same antiserum to MBP but one using peptide (45-89) as the radioligand and standard (peptide assay), and the other using purified MBP as the radioligand and standard (MBP assay), with respect to their diagnostic sensitivity. Cerebrospinal fluid specimens from 185 patients with definite multiple sclerosis (MS) (n = 27), possible MS (n = 63), probable MS (n = 24), and other neurological disease (n = 71) were analyzed using both assays. The diagnostic sensitivity of the peptide assay was significantly better than that of the MBP assay in those with definite MS (sensitivity 59% and 30%, respectively); there was no significant difference in specificity. The peptide assay also showed better correlation with disease activity than the MBP assay: 14 patients classified as having active MS showed significantly higher sensitivity (78.6% versus 38%, p less than 0.04) when compared to patients with inactive disease. The MBP assay showed no significant difference between these two groups. Besides the increase in sensitivity, the actual molar concentrations of immunoreactive MBP detected using this peptide assay were considerably higher than those found using the MBP assay. These results show that the use of MBP antisera capable of recognizing epitopes present in the carboxyl half of MBP peptide (45-89) results in more sensitive detection of immunoreactive MBP when used with MBP peptide (45-89) as radiolabeled ligand in the assay. 相似文献
50.