全文获取类型
收费全文 | 47210篇 |
免费 | 4361篇 |
国内免费 | 74篇 |
专业分类
耳鼻咽喉 | 612篇 |
儿科学 | 1270篇 |
妇产科学 | 1318篇 |
基础医学 | 6817篇 |
口腔科学 | 1252篇 |
临床医学 | 5789篇 |
内科学 | 8254篇 |
皮肤病学 | 596篇 |
神经病学 | 3785篇 |
特种医学 | 2127篇 |
外国民族医学 | 1篇 |
外科学 | 6157篇 |
综合类 | 860篇 |
一般理论 | 23篇 |
预防医学 | 5243篇 |
眼科学 | 1086篇 |
药学 | 3539篇 |
2篇 | |
中国医学 | 56篇 |
肿瘤学 | 2858篇 |
出版年
2021年 | 650篇 |
2019年 | 643篇 |
2018年 | 744篇 |
2017年 | 623篇 |
2016年 | 607篇 |
2015年 | 700篇 |
2014年 | 936篇 |
2013年 | 1462篇 |
2012年 | 2133篇 |
2011年 | 2214篇 |
2010年 | 1190篇 |
2009年 | 986篇 |
2008年 | 1856篇 |
2007年 | 2011篇 |
2006年 | 2005篇 |
2005年 | 1999篇 |
2004年 | 1818篇 |
2003年 | 1667篇 |
2002年 | 1698篇 |
2001年 | 1600篇 |
2000年 | 1706篇 |
1999年 | 1439篇 |
1998年 | 632篇 |
1997年 | 502篇 |
1996年 | 513篇 |
1995年 | 513篇 |
1994年 | 435篇 |
1993年 | 445篇 |
1992年 | 1253篇 |
1991年 | 1160篇 |
1990年 | 1149篇 |
1989年 | 1077篇 |
1988年 | 992篇 |
1987年 | 994篇 |
1986年 | 916篇 |
1985年 | 916篇 |
1984年 | 711篇 |
1983年 | 628篇 |
1982年 | 447篇 |
1981年 | 386篇 |
1980年 | 401篇 |
1979年 | 659篇 |
1978年 | 525篇 |
1977年 | 413篇 |
1976年 | 401篇 |
1975年 | 375篇 |
1974年 | 451篇 |
1973年 | 438篇 |
1972年 | 450篇 |
1971年 | 423篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Jeffrey T. Wieczorkiewicz Bert K. Lopansri Adam Cheknis James R. Osmolski David W. Hecht Dale N. Gerding Stuart Johnson 《Antimicrobial agents and chemotherapy》2016,60(1):418-423
Antibiotics have been shown to influence the risk of infection with specific Clostridium difficile strains as well as the risk of C. difficile infection (CDI). We performed a retrospective case-control study of patients infected with the epidemic BI/NAP1/027 strain in a U.S. hospital following recognition of increased CDI severity and culture of stools positive by C. difficile toxin immunoassay. Between 2005 and 2007, 72% (103/143) of patients with first-episode CDIs were infected with the BI strain by restriction endonuclease analysis (REA) typing. Most patients received multiple antibiotics within 6 weeks of CDI onset (median of 3 antibiotic classes). By multivariate analysis, fluoroquinolone and macrolide exposure was more frequent among BI cases than among non-BI-infected controls (odds ratio [OR] for fluoroquinolones, 3.2; 95% confidence interval [CI], 1.3 to 7.5; (P < 0.001; OR for macrolides, 5.2; 95% CI, 1.1 to 24.0; P = 0.04)). In contrast, clindamycin use was less frequent among the BI cases than among the controls (OR, 0.1; 95% CI, 0.03 to 0.4; P = 0.001). High-level resistance to moxifloxacin and azithromycin was more frequent among BI strains (moxifloxacin, 49/102 [48%] BI versus 0/40 non-BI, P = 0.0001; azithromycin, 100/102 [98%] BI versus 22/40 [55%] non-BI, P = 0.0001). High-level resistance to clindamycin was more frequent among non-BI strains (22/40 [55%] non-BI versus 7/102 [7%] BI, P = 0.0001). Fluoroquinolone use, macrolide use, and C. difficile resistance to these antibiotic classes were associated with infection by the epidemic BI strain of C. difficile in a U.S. hospital during a time when CDI rates were increasing nationally due to the highly fluoroquinolone-resistant BI/NAP1/027 strain. 相似文献
993.
A case study approach was used to study a 36‐year‐old Southern black female for several weeks following a hypertensive crisis episode. The purpose of the study was to establish trust and understanding between the culturally different black client and white nurse. The Betty Neuman model of nursing care was used in developing an ethnocare plan for the subject. Cultural Stressors identified were: (1) obesity and dietary habits, evidence of the “soul food”; diet and salt, saturated fats, and cholesterol; (2) smoking, used as a coping mechanism when under self‐perceived stress; (3) noncom‐pliance in taking hypertensive drugs, which reflects cultural beliefs and feelings; (4) lack of understanding about the disease process, an example of cultural difference in language and beliefs; (5) inability to be a biological mother (the ability to produce children is perceived by the black culture as necessary to the fulfillment of the woman's role); and (6) living in a hostile environment. The ethnocare plan addressed each of these Stressors and was designed to fit this client's individual perception of nursing care and its value to her. 相似文献
994.
995.
Pulmonary thromboembolism is an extremely common cause of respiratory distress, unremitting heart failure, and sudden death in elderly persons. 相似文献
996.
997.
998.
Steven R. Passmore Michael G. Johnson Saleh M. Aloraini Stephan Cooper Mina Aziz Cheryl M. Glazebrook 《Journal of manipulative and physiological therapeutics》2019,42(1):23-33
ObjectiveThe purpose of this study was to quantify the impact of a single lumbar spinal manipulation (SM) intervention on the leg movement performance of degenerative lumbar spinal stenosis (LSS) patients in a small-scale registered randomized clinical trial.MethodsParticipants with LSS (n = 14) were tested at baseline for pain, lumbar range of motion, and behavioral or kinematic motor performance (using an established Fitts’ Law foot-pointing task), then underwent covariate adaptive randomization to receive SM or no intervention. Postintervention all dependent measures were repeated. Experimenters were blinded to patient group allocation. University ethics board approval was attained.ResultsFor the primary outcome movement time, there was no significant difference between groups. As predicted by Fitts’ Law, all participants had longer movement times as task difficulty increased. Secondary kinematic outcomes yielded no significant between-group differences. Consistent with Fitts’ Law, kinematic measures changed significantly with task difficulty. Pairwise comparisons revealed the kinematic variables were more adversely affected by greater movement amplitudes than target size changes. No exploratory differences in pain or lumbar range of motion were observed.ConclusionChanges in motor performance were not observed in this chronic pain population after a single SM intervention compared with a control group. Given the sample size, the study may have been underpowered to detect meaningful differences. Fitts’ Law was observed for the lower extremity–pointing task for an LSS population and may provide an objective measure of motor performance. 相似文献
999.
1000.