全文获取类型
收费全文 | 11401篇 |
免费 | 1019篇 |
国内免费 | 71篇 |
专业分类
耳鼻咽喉 | 165篇 |
儿科学 | 423篇 |
妇产科学 | 236篇 |
基础医学 | 1642篇 |
口腔科学 | 275篇 |
临床医学 | 961篇 |
内科学 | 2640篇 |
皮肤病学 | 305篇 |
神经病学 | 1182篇 |
特种医学 | 363篇 |
外国民族医学 | 1篇 |
外科学 | 1738篇 |
综合类 | 53篇 |
一般理论 | 1篇 |
预防医学 | 806篇 |
眼科学 | 147篇 |
药学 | 750篇 |
中国医学 | 24篇 |
肿瘤学 | 779篇 |
出版年
2023年 | 57篇 |
2022年 | 139篇 |
2021年 | 325篇 |
2020年 | 194篇 |
2019年 | 292篇 |
2018年 | 381篇 |
2017年 | 260篇 |
2016年 | 299篇 |
2015年 | 332篇 |
2014年 | 383篇 |
2013年 | 551篇 |
2012年 | 689篇 |
2011年 | 692篇 |
2010年 | 429篇 |
2009年 | 355篇 |
2008年 | 558篇 |
2007年 | 570篇 |
2006年 | 624篇 |
2005年 | 550篇 |
2004年 | 485篇 |
2003年 | 379篇 |
2002年 | 427篇 |
2001年 | 329篇 |
2000年 | 317篇 |
1999年 | 271篇 |
1998年 | 122篇 |
1997年 | 113篇 |
1996年 | 93篇 |
1995年 | 104篇 |
1994年 | 79篇 |
1993年 | 54篇 |
1992年 | 224篇 |
1991年 | 192篇 |
1990年 | 177篇 |
1989年 | 172篇 |
1988年 | 163篇 |
1987年 | 129篇 |
1986年 | 119篇 |
1985年 | 111篇 |
1984年 | 95篇 |
1983年 | 64篇 |
1982年 | 45篇 |
1981年 | 33篇 |
1980年 | 35篇 |
1979年 | 64篇 |
1978年 | 34篇 |
1976年 | 33篇 |
1974年 | 40篇 |
1973年 | 42篇 |
1971年 | 34篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
Luis Veloza Cristina Teixido Natalia Castrejon Fina Climent Ana Carri Marta Marginet Davide Soldini Blanca Gonzlez‐Farr Inmaculada Ribera‐Cortada Armando Lopez‐Guillermo Eva Gonzlez‐Barca Adriana Sierra Mileyka Herrera Cndida Gmez Adriana Garcia Olga Balagu Elias Campo Antonio Martinez 《Histopathology》2019,75(6):799-812
3.
4.
5.
Phenotypic and genetic features of enteropathogenic Escherichia coli isolates from diarrheal children in the Ribeirão Preto metropolitan area,São Paulo State,Brazil 下载免费PDF全文
André Pitondo‐Silva Gerson Nakazato Juliana P. Falcão Kinue Irino Roberto Martinez Ana Lúcia C. Darini Rodrigo Tavanelli Hernandes 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(2):128-135
This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors‐encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype β was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence‐like (LAL) pattern to HEp‐2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non‐adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates. 相似文献
6.
7.
8.
Carmelo Tassi Antonio Angelini Tommaso Beccari Enrico Capodicasa 《Clinical chemistry and laboratory medicine》2006,44(7):843-847
BACKGROUND: The activity and isoenzyme composition of N-acetyl-beta-D-hexosaminidase (EC.3.2.1.52) in seminal plasma of fertile and infertile men have been evaluated. However, no data are available on the isoenzyme content in seminal plasma from patients with secretory azoospermia. METHODS: The activity and isoenzyme composition of seminal plasma from 15 normozoospermic controls and 18 patients with secretory azoospermia were determined by fluorimetric methods. 4-Methylumbelliferil-2-acetamido-2-deoxy-beta-D-glucopyranoside and 4-methylumbelliferil-2-acetamido-2-deoxy-beta-D-glucopyranoside-6-sulfate were used as fluorigenic substrates. Receiver-operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficiency of the assays. RESULTS: No significant difference was found in total enzyme activity between the two groups, while isoenzyme A activity was significantly lower (p=0.004) and the ratio between total enzyme activity and isoenzyme A activity was significantly higher (p=0.04) in azoospermic patients compared to controls. The diagnostic efficiency of these evaluations was low (< or =75.7%). CONCLUSIONS: Our findings show that the isoenzyme composition of N-acetyl-beta-D-hexosaminidase in seminal plasma from patients with secretory azoospermia is significantly different from controls, but this difference does not represent a useful marker of secretory azoospermia. The fluorimetric assays are simple and rapid methods for evaluating the isoenzyme composition. 相似文献
9.
10.
New diuretics introduced into clinical medicine during the past decade include potent new loop diuretics such as bumetanide and piretanide, the uricosuric indanyloxyacetic acid derivative indacrinone, and a new generation of sulfamoyl diuretics such as indapamide and xipamide, which are recommended primarily for the treatment of hypertension. Pharmacokinetic studies of individual diuretics have demonstrated that the diuretic and natriuretic responses to the newer agents generally follow the plasma drug concentration-time curves and urinary drug excretion rates. Therapeutic monitoring can therefore be achieved in most patients with edema or hypertension by close clinical observation and laboratory analysis of plasma electrolyte and creatinine concentrations and urinary electrolyte excretion rates. Interest in the mechanisms involved in the renal and extrarenal vascular actions of the newer diuretics has led to a better understanding of how changes in venous compliance, peripheral vascular resistance, and renal blood flow distribution may contribute to the overall therapeutic response to these agents, especially in patients with severe congestive heart failure, renal insufficiency with low glomerular filtration rates, and hypertension with cardiorenal complications. Adverse reactions to modern diuretics, which are mainly an extension of their renal pharmacodynamic effects, have proved to be minimal, provided that the dosage is adjusted to meet but not exceed individual patient requirements. However, the long-term consequences of prolonged periods of diuretic-induced alterations in plasma potassium levels, and metabolic effects that include elevated blood lipids, are still under investigation. 相似文献