全文获取类型
收费全文 | 5202篇 |
免费 | 348篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 109篇 |
妇产科学 | 143篇 |
基础医学 | 1195篇 |
口腔科学 | 93篇 |
临床医学 | 459篇 |
内科学 | 868篇 |
皮肤病学 | 128篇 |
神经病学 | 624篇 |
特种医学 | 196篇 |
外科学 | 454篇 |
综合类 | 46篇 |
一般理论 | 7篇 |
预防医学 | 410篇 |
眼科学 | 59篇 |
药学 | 307篇 |
中国医学 | 6篇 |
肿瘤学 | 451篇 |
出版年
2023年 | 47篇 |
2022年 | 89篇 |
2021年 | 143篇 |
2020年 | 111篇 |
2019年 | 108篇 |
2018年 | 128篇 |
2017年 | 122篇 |
2016年 | 157篇 |
2015年 | 179篇 |
2014年 | 208篇 |
2013年 | 278篇 |
2012年 | 412篇 |
2011年 | 446篇 |
2010年 | 200篇 |
2009年 | 196篇 |
2008年 | 321篇 |
2007年 | 294篇 |
2006年 | 288篇 |
2005年 | 280篇 |
2004年 | 247篇 |
2003年 | 228篇 |
2002年 | 180篇 |
2001年 | 40篇 |
2000年 | 35篇 |
1999年 | 42篇 |
1998年 | 24篇 |
1997年 | 20篇 |
1996年 | 13篇 |
1992年 | 18篇 |
1990年 | 17篇 |
1989年 | 15篇 |
1988年 | 13篇 |
1972年 | 13篇 |
1943年 | 16篇 |
1942年 | 30篇 |
1941年 | 30篇 |
1940年 | 38篇 |
1939年 | 14篇 |
1938年 | 18篇 |
1937年 | 23篇 |
1936年 | 27篇 |
1935年 | 18篇 |
1934年 | 35篇 |
1933年 | 19篇 |
1931年 | 14篇 |
1929年 | 16篇 |
1928年 | 29篇 |
1927年 | 29篇 |
1926年 | 35篇 |
1925年 | 38篇 |
排序方式: 共有5571条查询结果,搜索用时 15 毫秒
71.
Melchior Weisshuhn Christeller K. Hirschfeld Meyer Schrader W. Fischer Mendel Starkenstein Koenigsfeld Dietrich Eckstein Peiper Cramer Schall Grassheim Herzfeld Deusch Eisner-Behrend Weigert Hofmeier H. Hirschfeld Rosenow H. Staub Gottschalk Bernhardt O. Wiener Straus Lange Vogel Sturmann 《Journal of molecular medicine (Berlin, Germany)》1925,4(40):1929-1936
Ohne Zusammenfassung 相似文献
72.
E. Martini Buschke Christeller Fischer Oppenheimer Edens Peiper W. Heubner Schübel Koenigsfeld Goldstein Herzfeld Erich Langer Bernhardt Eisner Carl v. Noorden Nothmann Weigert Griesbach Gottschalk Rosenberg W. Israel Freudenberg Sperling Dietrich Jonas Schrader Finkenrath K. Goldstein Mendel O. Wiener 《Journal of molecular medicine (Berlin, Germany)》1925,4(37):1785-1793
Ohne Zusammenfassung 相似文献
73.
Melchior A. W. Fischer Christeller Sperling Finkenrath Wolfgang Weichardt Bernhardt Herzfeld Deusch Zinn Holzer Schrader Levinger Warsow W. Fischer H. Hirschfeld Weigert Dietrich Weigerau v. Jaschke Jonas Buschke Heyn Erich Langer O. Wiener K. Hirschfeld Mendel Straus Eugen Kahn 《Journal of molecular medicine (Berlin, Germany)》1925,4(21):1034-1040
74.
Günther Just Gaupp Straus Dietlen Schall Herzfeld Strads Meyer Starkenstein Oppenheimer Bernhardt Schübel Dietrich Koenigsfeld Cramer K. Hirschfeld Halberstaedter Braun Sperling Seligmann Buschke Deusch Hofmeier Erich Langer A. W. Fischer Weigert Peiper Levinger Mendel Eckstein Schrader Jonas O. Wiener Ietrich Finkenrath Jadassohn Heyn W. V. Simon Valentin 《Journal of molecular medicine (Berlin, Germany)》1925,4(24):1177-1185
Ohne Zusammenfassung 相似文献
75.
Margareta Larsson Minna Berglund Emelie Jarl Tanja Tydén 《Upsala journal of medical sciences》2017,122(4):254-259
Background: The aim of the study was to investigate if expecting parents wanted to know the sex of the fetus during ultrasound examination and if they had discussed it with the midwife. Another aim was to explore any interest in sex selection.Methods: A longitudinal survey in early and late pregnancy among 2393 women in Sweden.Results: Almost all (95.8%, n?=?2289) women had discussed sex determination with the partner before the ultrasound scan, and 57% (n?=?1356) of women and their partners wanted to find out the fetal sex. The expecting parents mostly initiated a discussion with the midwife (46%, n?=?1088), but 10% (n?=?229) stated that the midwives initiated the discussion. Few (5%, n?=?118) expressed a potential interest in selecting sex of a baby. Women who were interested in sex determination did not differ from those who were not, with respect to age, origin, education, parity, level of pregnancy planning, or importance of religion, but women who had chosen another fetal diagnostic method were more interested in sex determination and in potential sex selection.Conclusions: Half of women and their partners wanted to know the fetal sex, and 5% were interested in sex selection. This high interest in sex determination is a challenge, since present national guidelines do not include sex determination as an option. 相似文献
76.
ABSTRACT: BACKGROUND: Older adults receiving inpatient rehabilitation have low activity levels and poor mobility outcomes. Increased physical activity may improve mobility. The objective of this Phase II study was to evaluate the feasibility of a randomized controlled trial (RCT) of enhanced physical activity in older adults receiving rehabilitation. METHODS: Patients admitted to aged care rehabilitation with reduced mobility were randomised to receive usual care or usual care plus additional physical activity, which was delivered by a physiotherapist or physiotherapy assistant. The feasibility and safety of the proposed RCT protocol was evaluated. The primary clinical outcome was mobility, which was assessed on hospital admission and discharge by an assessor blinded to group assignment. To determine the most appropriate measure of mobility, three measures were trialled; the Timed Up and Go, the Elderly Mobility Scale and the de Morton Mobility Index. RESULTS: The protocol was feasible. Thirty-four percent of people admitted to the ward were recruited, with 47 participants randomised to a control (n = 25) or intervention group (n = 22). The rates of adverse events (death, falls and readmission to an acute service) did not differ between the groups. Usual care therapists remained blind to group allocation, with no change in usual practice. Physical activity targets were met on weekdays but not weekends and the intervention was acceptable to participants. The de Morton Mobility Index was the most appropriate measure of mobility. CONCLUSIONS: The proposed RCT of enhanced physical activity in older adults receiving rehabilitation was feasible. A larger multi-centre RCT to establish whether this intervention is cost effective and improves mobility is warranted. Trial registration The trial was registered with the ANZTCR (ACTRN12608000427370). 相似文献
77.
Miriam Nannette Ebert Gabriele Beyer-Sehlmeyer Ute Monika Liegibel Tanja Kautenburger Thomas Walter Becker Beatrice Louise Pool-Zobel 《Nutrition and cancer》2013,65(1-2):156-164
Butyrate, one of the major products of gut fermentation, is known to inhibit proliferation, induce apoptosis and differentiation, and increase phase II enzyme activities in tumor cells, whereas little information is available on protective effects in less-transformed colon cells. The aim of this study was to investigate whether the chemoprotective mechanism of glutathione S-transferase (GST) induction by butyrate could also play a role in earlier stages of colon carcinogenesis and whether chemoresistance of cells toward the endogenous genotoxic risk factor 4-hydroxy-2-nonenal (HNE) could be a consequence of butyrate treatment. As cell models, we used the human tumor cell lines HT29 and HT29 clone 19A, a differentiated subclone with properties resembling primary colon cells. We determined the expression of GSTP1 protein (enzyme-linked immunosorbent assay), the major GST in HT29, GSTP1 mRNA (Northern blotting), GST activity, intracellular glutathione, and total protein. The genotoxic impact of HNE (100-200 μM) was compared in butyrate-treated and nontreated cells using single-cell microgel electrophoresis. Our results show that GSTP1 mRNA, GSTP1 protein, GST activity, and total protein were increased (1.2- to 2.5-fold) and glutathione levels were maintained after 24- 72 h of incubation with 4 mM butyrate. Moreover, a marked reduction of HNE-induced genotoxicity was caused by preincubation with butyrate. Butyrate also induced the phosphorylation of extracellular signal-regulated kinases (ERK1/2, Western blotting) after 5-30 min, which indicates a regulation of GST expression by this signal pathway. Most effects were greater in HT29 parent cells than in clone cells. In conclusion, butyrate enhances expression of GST and other proteins in both cell lines, which leads to an enhanced chemoprotection, reducing the impact of HNE genotoxicity. Thus butyrate could play a role in early and later stages of cancer prevention by reducing exposure to relevant risk factors. 相似文献
78.
79.
80.
Tanja H. Geelen John W. Rossen Antoine M. Beerens Linda Poort Servaas A. Morré Wilma S. Ritmeester Harry E. van Kruchten Masja M. van de Pas Paul H.M. Savelkoul 《Diagnostic microbiology and infectious disease》2013
A prospective, multicenter trial was designed to compare the performance characteristics of the cobas® 4800 (Roche Diagnostics, Indianapolis, IN, USA) and m2000 real-time™ (Abbott Molecular Inc., Des Plaines, IL, USA) assays for detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in rectal and self-collected vaginal swabs. Rectal (n = 234) or self-collected vaginal swabs (n = 687) were obtained from consenting individuals visiting their general practitioners, dermatologists, gynecologists, sexually transmitted disease clinics, or family planning centers from May 2010 to February 2011. High concordance rates (≥96%) were observed between the cobas® 4800 and m2000 real-time™ assays for CT/NG detection in both rectal and self-collected vaginal swabs. The performance profiles confirm the usefulness of both kinds of swab types for CT and NG detection using described nucleic acid amplification tests assays. Based on this study, rectal and self-collected vaginal swabs offer a noninvasive alternative, which may improve screening for CT and NG infections. 相似文献