全文获取类型
收费全文 | 2343篇 |
免费 | 283篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 105篇 |
妇产科学 | 59篇 |
基础医学 | 343篇 |
口腔科学 | 32篇 |
临床医学 | 294篇 |
内科学 | 362篇 |
皮肤病学 | 39篇 |
神经病学 | 258篇 |
特种医学 | 164篇 |
外科学 | 414篇 |
综合类 | 58篇 |
一般理论 | 1篇 |
预防医学 | 200篇 |
眼科学 | 8篇 |
药学 | 187篇 |
中国医学 | 5篇 |
肿瘤学 | 96篇 |
出版年
2021年 | 38篇 |
2020年 | 22篇 |
2019年 | 39篇 |
2018年 | 48篇 |
2017年 | 31篇 |
2016年 | 31篇 |
2015年 | 49篇 |
2014年 | 53篇 |
2013年 | 79篇 |
2012年 | 78篇 |
2011年 | 64篇 |
2010年 | 62篇 |
2009年 | 72篇 |
2008年 | 73篇 |
2007年 | 81篇 |
2006年 | 83篇 |
2005年 | 79篇 |
2004年 | 89篇 |
2003年 | 64篇 |
2002年 | 67篇 |
2001年 | 84篇 |
2000年 | 70篇 |
1999年 | 59篇 |
1998年 | 49篇 |
1997年 | 53篇 |
1996年 | 56篇 |
1995年 | 49篇 |
1994年 | 45篇 |
1993年 | 52篇 |
1992年 | 61篇 |
1991年 | 52篇 |
1990年 | 42篇 |
1989年 | 56篇 |
1988年 | 62篇 |
1987年 | 46篇 |
1986年 | 49篇 |
1985年 | 43篇 |
1984年 | 35篇 |
1983年 | 37篇 |
1982年 | 35篇 |
1981年 | 28篇 |
1980年 | 25篇 |
1979年 | 34篇 |
1978年 | 39篇 |
1977年 | 30篇 |
1976年 | 29篇 |
1975年 | 25篇 |
1974年 | 21篇 |
1973年 | 18篇 |
1972年 | 16篇 |
排序方式: 共有2630条查询结果,搜索用时 15 毫秒
971.
972.
973.
974.
Compared three groups of black, white, and Mexican-American delinquent and nondelinquent males, aged 11 to 18, on measures of self-concept, self-esteem, and ordinal position by groups (N = 135). Data were analyzed with analysis of variance and Chi-square test. Significant main effects were found with respect to delinquency, self-concept, and self-esteem. A significant interaction was present for delinquency and ethnicity for both self-concept and self-esteem. Chi-square results found birth-order and ethnicity to be related significantly. 相似文献
975.
H K Poulsen J G Westergaard B Teisner A E Bolton R G Norman J G Grudzinskas 《European journal of obstetrics, gynecology, and reproductive biology》1987,26(1):33-37
Seven out of 54 women with ectopic gestation had uncommon features such as extra-tubal implantation or multiple intratubal pregnancy. Depressed levels (less than 10th centile) or apparent absence of circulating human chorionic gonadotrophin (hCG) and pregnancy-associated plasma protein A (PAPP-A) were seen respectively in 5 and 7 of 7 women studied. Normal levels of hCG were seen in two women, one with an abdominal and one with an angular pregnancy. These data suggest that the synthesis of placental proteins in ectopic pregnancies is independent of the site of implantation and the number of embryos. Measurements of maternal levels of the 2 placental proteins seem to be applicable as auxiliary diagnostic tests for ectopic pregnancy, regardless of the site of implantation. 相似文献
976.
977.
W. Kline Bolton Paul M. Suratt Benjamin C. Sturgill 《The American journal of medicine》1981,71(5):823-828
Rapidly progressive renal failure developed in four patients with silica exposure. Three presented with manifestations of a connective tissue disorder. All had abnormal proteinuria, hypoalbuminemia and active urinary sediments. Histologically, a distinct constellation of findings was present, consisting of glomerular hypercellularity and sclerosis, crescents, interstitial cellular infiltrates and tubular necrosis with red cell casts as seen on light microscopy. On electron microscopy there was foot process obliteration, characteristic cytoplasmic dense lysosomes, microtubules and dense deposits. Despite vigorous treatment, two patients died of the systemic illness and one is on hemodialysis. The fourth is improved after pulse methylprednisolone therapy. We propose that silica induced this multisystem disease through activation of the immune system and a direct tissue toxic effect. 相似文献
978.
AE Khatab NM Hashem LM El-Kodary FM Lotfy GA Hassan 《Biomedical and environmental sciences : BES》2016,(10):762-766
正The prophylactic effects of Chinese propolis against cypermethrin toxicity were evaluated by performing ovary and uterus histopathology,as well as by characterizing ovarian function,embryos,and litters.Cypermethrin induced atypia in the ovary and uterus,and decreased the ovulation sites and the number of embryos.Cypermethrin-induced oxidative stress during pregnancy,decreased the parturition rate as well as the number and weight 相似文献
979.
Alloantibody Responses After Renal Transplant Failure Can Be Better Predicted by Donor–Recipient HLA Amino Acid Sequence and Physicochemical Disparities Than Conventional HLA Matching 下载免费PDF全文
V. Kosmoliaptsis D. H. Mallon Y. Chen E. M. Bolton J. A. Bradley C. J. Taylor 《American journal of transplantation》2016,16(7):2139-2147
We have assessed whether HLA immunogenicity as defined by differences in donor–recipient HLA amino‐acid sequence (amino‐acid mismatch score, AMS; and eplet mismatch score, EpMS) and physicochemical properties (electrostatic mismatch score, EMS) enables prediction of allosensitization to HLA, and also prediction of the risk of an individual donor–recipient HLA mismatch to induce donor‐specific antibody (DSA). HLA antibody screening was undertaken using single‐antigen beads in 131 kidney transplant recipients returning to the transplant waiting list following first graft failure. The effect of AMS, EpMS, and EMS on the development of allosensitization (calculated reaction frequency [cRF]) and DSA was determined. Multivariate analyses, adjusting for time on the waiting list, maintenance on immunosuppression after transplant failure, and graft nephrectomy, showed that AMS (odds ratio [OR]: 1.44 per 10 units, 95% CI: 1.02–2.10, p = 0.04) and EMS (OR: 1.27 per 10 units, 95% CI: 1.02–1.62, p = 0.04) were independently associated with the risk of developing sensitization to HLA (cRF > 15%). AMS, EpMS, and EMS were independently associated with the development of HLA‐DR and HLA‐DQ DSA, but only EMS correlated with the risk of HLA‐A and ‐B DSA development. Differences in donor–recipient HLA amino‐acid sequence and physicochemical properties enable better assessment of the risk of HLA‐specific sensitization than conventional HLA matching. 相似文献
980.