全文获取类型
收费全文 | 41637篇 |
免费 | 2130篇 |
国内免费 | 178篇 |
专业分类
耳鼻咽喉 | 612篇 |
儿科学 | 1090篇 |
妇产科学 | 873篇 |
基础医学 | 5418篇 |
口腔科学 | 2871篇 |
临床医学 | 2919篇 |
内科学 | 9794篇 |
皮肤病学 | 1147篇 |
神经病学 | 3684篇 |
特种医学 | 1125篇 |
外国民族医学 | 3篇 |
外科学 | 4768篇 |
综合类 | 266篇 |
一般理论 | 12篇 |
预防医学 | 3744篇 |
眼科学 | 937篇 |
药学 | 2960篇 |
中国医学 | 274篇 |
肿瘤学 | 1448篇 |
出版年
2023年 | 329篇 |
2022年 | 726篇 |
2021年 | 1433篇 |
2020年 | 789篇 |
2019年 | 1205篇 |
2018年 | 1538篇 |
2017年 | 984篇 |
2016年 | 1062篇 |
2015年 | 1192篇 |
2014年 | 1616篇 |
2013年 | 2048篇 |
2012年 | 3106篇 |
2011年 | 3349篇 |
2010年 | 1811篇 |
2009年 | 1448篇 |
2008年 | 2498篇 |
2007年 | 2449篇 |
2006年 | 2203篇 |
2005年 | 2005篇 |
2004年 | 1865篇 |
2003年 | 1520篇 |
2002年 | 1438篇 |
2001年 | 905篇 |
2000年 | 921篇 |
1999年 | 743篇 |
1998年 | 292篇 |
1997年 | 205篇 |
1996年 | 199篇 |
1995年 | 159篇 |
1994年 | 168篇 |
1993年 | 123篇 |
1992年 | 328篇 |
1991年 | 305篇 |
1990年 | 286篇 |
1989年 | 238篇 |
1988年 | 264篇 |
1987年 | 235篇 |
1986年 | 175篇 |
1985年 | 194篇 |
1984年 | 142篇 |
1983年 | 138篇 |
1982年 | 65篇 |
1981年 | 67篇 |
1980年 | 76篇 |
1979年 | 108篇 |
1978年 | 91篇 |
1977年 | 71篇 |
1975年 | 68篇 |
1971年 | 79篇 |
1967年 | 75篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
83.
84.
85.
Contact between the sexes in many species is known to produce hormonal changes in the male [increases in serum luteinizing hormone (LH) and/or testosterone] that can be interpreted as due to an intracerebral release of LH-releasing hormone (LHRH). In some circumstances, these hormonal changes appear to depend on an intact vomeronasal sensory system. Exogenous LHRH is also known to facilitate mating behavior in several species. We show here that LHRH delivered into the cerebral ventricles can restore some mating behavior lost when the vomeronasal organs are removed from sexually inexperienced male hamsters. The results are consistent with our working hypothesis that intracerebral LHRH release is an intermediate in the facilitation of mating behavior by vomeronasal sensory input. 相似文献
86.
M Guerrero Fernández J L Alfonso Sánchez B Sanchís Noguera M J Prado del Ba?o 《Gaceta sanitaria / S.E.S.P.A.S》1992,6(29):62-66
Data are presented on hospital stay for the population 65 years-old and over, measured in percentage over the total for Spain, for the 1978 to 1988 period, by gender, for each province and autonomous region (Comunidad Autónoma). The country's total for the last available year was 35%. Except in Baleares and Murcia, the proportion of hospital stays increased in all Regions, especially in Navarra, where it increased from 23% to 51%. After adjusting for age, the increase in the proportion of hospital stays in the study population was due to an increase in utilization per person. The proportion, which was 13.3% in 1978, raised to 23.8% in 1988, with an adjusted value of 21.3%. 相似文献
87.
88.
Michelle Lucinda DeOliveira M.D. Tarcisio Triviño M.D. Ph.D. Gaspar de Jesus Lopes Filho M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(8):1140-1143
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies.
Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable
than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor,
although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis
of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance
and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with
final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison
was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy
were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although
preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value
of the endoscopic appearance was superior to endoscopic biopsy in this series.
Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003.
Supported by FADA-CAPES/PROP 200J (M.L.D.). 相似文献
89.
Marta Padilla Castillo Yaiza Machado RyderManuel Cazorla Betancor Rocío Acebes TostiMargarita Medina Castellano Rosa Rodríguez-Mano 《Progresos de Obstetricia y Ginecología》2006
Heterotopic pregnancy is the combination of intrauterine and ectopic pregnancy. This potentially fatal condition rarely occurs in spontaneous conception cycles and consequently its diagnosis requires a high index of suspicion. We report a case of heterotopic pregnancy in a 30-year old primipara with no known risk factors who presented with acute abdominal pain due to a spontaneous heterotopic pregnancy. The ectopic pregnancy was resected via laparoscopy. After surgery, the intrauterine pregnancy was uneventful. 相似文献
90.
The spectrometric analysis of extracts from tobacco and tobacco smoke revealed the presence of pentobarbital in the analyzed substances. Tobacco samples and tobacco smoke were extracted with chloroform, determinations were performed with the Perkin-Elmer Autosystem XL system, on a Turbo Mass spectrometer. Subject to analysis were 4 cigarette brands manufactured in Poland and raw, unprocessed tobacco. The presence of pentobarbital in the analyzed samples was confirmed by the analysis of the mass spectrum of the substance, as well as by comparison of retention time with standard of pentobarbital. The determined pentobarbital concentrations in tobacco amounted to 3-6 microg/cigarette, and in tobacco smoke they were approximately 45% lower. In case of tobacco extracts it can with high probability be excluded that pentobarbital is synthesized during chromatographical analysis. The presence of pentobarbital in tobacco is thus beyond question. 相似文献