全文获取类型
收费全文 | 4960篇 |
免费 | 457篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 61篇 |
儿科学 | 79篇 |
妇产科学 | 85篇 |
基础医学 | 736篇 |
口腔科学 | 143篇 |
临床医学 | 719篇 |
内科学 | 976篇 |
皮肤病学 | 116篇 |
神经病学 | 403篇 |
特种医学 | 127篇 |
外科学 | 593篇 |
综合类 | 74篇 |
一般理论 | 10篇 |
预防医学 | 452篇 |
眼科学 | 78篇 |
药学 | 373篇 |
中国医学 | 6篇 |
肿瘤学 | 393篇 |
出版年
2023年 | 29篇 |
2022年 | 42篇 |
2021年 | 78篇 |
2020年 | 61篇 |
2019年 | 93篇 |
2018年 | 105篇 |
2017年 | 78篇 |
2016年 | 84篇 |
2015年 | 90篇 |
2014年 | 140篇 |
2013年 | 215篇 |
2012年 | 339篇 |
2011年 | 336篇 |
2010年 | 197篇 |
2009年 | 175篇 |
2008年 | 287篇 |
2007年 | 271篇 |
2006年 | 238篇 |
2005年 | 277篇 |
2004年 | 286篇 |
2003年 | 256篇 |
2002年 | 197篇 |
2001年 | 140篇 |
2000年 | 134篇 |
1999年 | 97篇 |
1998年 | 67篇 |
1997年 | 46篇 |
1996年 | 56篇 |
1995年 | 42篇 |
1994年 | 40篇 |
1993年 | 39篇 |
1992年 | 71篇 |
1991年 | 58篇 |
1990年 | 52篇 |
1989年 | 42篇 |
1988年 | 54篇 |
1987年 | 55篇 |
1986年 | 40篇 |
1985年 | 43篇 |
1984年 | 42篇 |
1983年 | 42篇 |
1982年 | 29篇 |
1981年 | 29篇 |
1980年 | 24篇 |
1979年 | 35篇 |
1978年 | 30篇 |
1977年 | 28篇 |
1968年 | 22篇 |
1967年 | 18篇 |
1966年 | 18篇 |
排序方式: 共有5424条查询结果,搜索用时 15 毫秒
1.
2.
Silvia Ciairano Silvia Bonino Wendy Kliewer Renato Miceli Sandy Jackson 《Journal of clinical child and adolescent psychology》2006,35(2):275-282
Associations among dating, sexual activity, gender, and adjustment were investigated in 2,273 Italian adolescents (54% female, ages 14 to 19 years) attending public high schools. After controlling for age and type of school attended, both being in a dating relationship and being male were associated with less alienation, more positive views of the self, and higher general expectations for success. Sexual activity interacted with both gender and dating status in predicting feelings of depression. For boys, there were no differences between youth who were sexually active and youth who were not; however, sexually active girls had higher levels of depressive symptoms than girls who were not sexually active. Among youth who were not sexually active, there were small differences between daters and nondaters; among sexually active youth, daters had lower levels of depression than nondaters. Gender differences in adolescents' experience of dating and sexual relationships and implications for adjustment are discussed. 相似文献
3.
P J Hayden C J Welsh Y Yang W H Schaefer A J Ward J L Stevens 《Chemical research in toxicology》1992,5(2):232-237
Nephrotoxic cysteine conjugates derived from a variety of halogenated alkenes are enzymatically activated via the beta-lyase pathway to yield reactive sulfur-containing metabolites which bind covalently to cellular macromolecules. Mitochondria contain beta-lyase enzymes and are primary targets for binding and toxicity. Previously, mitochondrial protein and/or DNA have been considered as molecular targets for cysteine conjugate metabolite binding. We now report that metabolites of nephrotoxic cysteine conjugates form covalent adducts with rat kidney mitochondrial phospholipids. Rat kidney mitochondria were incubated with the 35S-labeled conjugates S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC), S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC), S-(1,2-dichlorovinyl)-L-cysteine, and S-(1,2,3,4,4-pentachlorobutadienyl)-L-cysteine. Quantitation of metabolite binding to whole mitochondria and to mitochondrial protein and lipid fractions revealed that as much as 42% of the 35S-label associated with the mitochondria was found in the lipid fraction. Total lipids were also extracted from 35S-treated mitochondria and separated by thin-layer chromatography. 35S-Containing metabolites were found in the lipid fractions from mitochondria treated with each of the conjugates. Lipids from both [35S]CTFC- and [35S]-TFEC-treated mitochondria contained major 35S-labeled lipid adducts which had similar mobility by thin-layer chromatography. Fatty acid analysis, 19F and 31P NMR spectroscopy, and mass spectrometric analyses confirmed that the major TFEC and CTFC adducts are thioamides of phosphatidylethanolamine. 相似文献
4.
5.
6.
7.
Maternal serum and amniotic fluid alpha-fetoprotein testing has increased significantly in our laboratory and throughout the state since 1985. The results of this test are reported in a novel fashion as multiples of the median. The calculation and reporting of the test results are highly dependent upon gestational age, maternal weight, race and presence or absence of maternal diabetes. When properly interpreted alpha-fetoprotein determinations are a good screening test for early detection of neural tube defects and Trisomy 21 (Down Syndrome). Our approach to screening, diagnosis and counseling is discussed. 相似文献
8.
Gerald S. Lipshutz Harish Mahanty Sandy Feng Ryutaro Hirose Peter G. Stock Sang-Mo Kang rew M. Posselt Chris E. Freise 《American journal of transplantation》2005,5(2):366-373
With the introduction of more potent immunosuppressive agents, rejection has decreased in simultaneous pancreas/kidney transplant (SPK) recipients. However, as a consequence, opportunistic infections have increased. The purpose of this report is to outline the course of SPK patients who developed polyomavirus-associated nephropathy (PVAN). A retrospective review of 146 consecutive SPK recipients from January 1, 1996 to December 31, 2002 was performed. Immunosuppression, rejection and development of PVAN were reviewed. Nine patients were identified. All received induction with either OKT3 or thymoglobulin. Immunosuppression included tacrolimus/cyclosporine, MMF/azathioprine and sirolimus/prednisone. Two patients were treated for kidney rejection prior to the diagnosis of PVAN. Time to diagnosis was an average of 359.3 days post-transplantation. Immunosuppression was decreased but five ultimately lost function. However, none developed pancreatic abnormalities as demonstrated by normal glucose and amylase. Two underwent renal retransplantation after PVAN diagnosis and both have normal kidney function. PVAN was the leading cause of renal loss in SPK patients in the first 2 years after transplantation and is a serious concern for SPK recipients. The pancreas, however, is spared from evidence of infection, and no pancreatic rejection occurred when immunosuppression was decreased. 相似文献
9.