首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   12986篇
  免费   851篇
  国内免费   93篇
耳鼻咽喉   94篇
儿科学   317篇
妇产科学   184篇
基础医学   1462篇
口腔科学   321篇
临床医学   1260篇
内科学   3130篇
皮肤病学   266篇
神经病学   665篇
特种医学   287篇
外国民族医学   4篇
外科学   2212篇
综合类   397篇
现状与发展   1篇
一般理论   7篇
预防医学   907篇
眼科学   248篇
药学   1232篇
中国医学   211篇
肿瘤学   725篇
  2024年   15篇
  2023年   204篇
  2022年   531篇
  2021年   921篇
  2020年   527篇
  2019年   651篇
  2018年   642篇
  2017年   435篇
  2016年   486篇
  2015年   536篇
  2014年   634篇
  2013年   759篇
  2012年   1152篇
  2011年   1116篇
  2010年   561篇
  2009年   478篇
  2008年   727篇
  2007年   630篇
  2006年   581篇
  2005年   546篇
  2004年   428篇
  2003年   386篇
  2002年   261篇
  2001年   66篇
  2000年   59篇
  1999年   57篇
  1998年   49篇
  1997年   27篇
  1996年   30篇
  1995年   28篇
  1994年   28篇
  1993年   33篇
  1992年   26篇
  1991年   12篇
  1990年   23篇
  1989年   29篇
  1988年   26篇
  1987年   25篇
  1986年   15篇
  1985年   14篇
  1984年   20篇
  1983年   17篇
  1982年   20篇
  1981年   25篇
  1980年   10篇
  1979年   8篇
  1978年   9篇
  1977年   11篇
  1976年   7篇
  1975年   8篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Sonography is widely used for evaluation of hand and wrist lesions. The easy accessibility, cost‐effectiveness, and good diagnostic accuracy of sonography coupled with the numerous benefits of real‐time imaging make it desirable. The aim of this article is to describe the typical sonographic appearances of lesions in the hand and wrist that are encountered frequently in routine clinical practice, such as inflammatory arthropathies, tumors, traumatic injuries, foreign bodies, and nerve entrapment syndromes. Relevant anatomy, scanning methods, and recent developments in musculoskeletal sonography are also discussed.  相似文献   
992.
The aim of this study was to assess the frequency and genotypic diversity of carbapenemase-producing Enterobacteriaceae (CPE) in stool samples from patients attending a military hospital in Pakistan. Further aims included the identification of factors that might predispose to faecal carriage and evaluation of 2 chromogenic culture media: Brilliance CRE and chromID CARBA. Of 175 patients, 32 (18.3%) had faecal carriage of CPE and all produced NDM-1 carbapenemase. All of these 32 patients were detected using chromID CARBA compared with 20 patients (62.5%) detected using Brilliance CRE (P = 0.0015). Duration of hospitalization and treatment with co-amoxyclav were statistically associated with a higher likelihood of carriage of CPE (P ≤ 0.05). The majority of NDM-1–producing Enterobacteriaceae co-produced CTX-M-1 group extended spectrum β-lactamase, and one third produced armA-type methylase. NDM-1 carbapenemase was most commonly found amongst commensal types of Escherichia coli, especially phylogenetic group B1.  相似文献   
993.
994.
995.
996.
997.
Posterior reversible encephalopathy syndrome (PRES) is a rare complication of nephrotic syndrome and corticosteroid therapy. Here, we discuss an 18 year old man with type 1 membranoproliferative glomerulonephritis (MPGN) secondary to hepatitis B infection who developed posterior leukoencephalopathy while on therapy with lamivudine and prednisone. He developed seizures and vision loss. He also had hypertension, but no sudden elevation was recorded at any time. Magnetic resonance imaging revealed patchy areas of altered signal intensity involving cortical gray and subcortical white matter in the bilateral frontoparietal regions, occipital cortices, temporal cortices and cerebellar hemispheres, and hyperintensity on T2W and FLAIR sequences. Tapering of prednisone and controlling hypertension resulted in clinical improvement within a few days, and in a month MRI was normal. Diagnosing PRES requires a high index of suspicion when treating similarly susceptible patients. PRES as a complication during the treatment of MPGN secondary to hepatitis B has, to our knowledge, never been reported previously in the literature.  相似文献   
998.
This work aimed at isolation and identification of patulin producing fungi and to follow the presence of patulin during apple juice processing. Among 34 Penicillium isolates, eight isolates (five from healthy appeared apples and 12 from rot spotted apples) were considered as patulin producers using thin-layer chromatography. These isolates were classically identified as a Penicillium expansum. PCR utilizing primers based on the polygalacturonase gene of P. expansum was applied for detecting this mold. The PCR amplified a 404-bp DNA product from all tested P. expansum isolates, but not in other common food spoilage Penicillium species. RAPD technique using P1 or M13 primers was applied to determine the similarity of the P. expansum isolates. RAPD results revealed that the tested strains showed high percentage of similarity and no correlation was observed between cluster analysis and the sources of isolation. Patulin could not be detected in healthy appeared apples and their extracted juice during different stages of juice process. In apple juice made from the healthy parts of apples decayed by P. expansum contained patulin which may present health hazard. The obtained results assured that patulin is known to be stable in apple juice even after pasteurization. In conclusion, the removal of the rotten part from the fruit is not sufficient to eliminate the mycotoxin patulin from apple juice. Although, the enzyme treatment (pectinase and amylase) and pasteurization (95 °C for 7 min) significantly (p < 0.05) reduced patulin level, its level is still higher than the level of <50 μg/kg considered by Codex alimentarius when the apple juice processed from the healthy parts of rot spotted fruits.  相似文献   
999.
Hashmi  Jamil A.  Zafar  Yusuf  Arshad  Muhammad  Mansoor  Shahid  Asad  Shaheen 《Virus genes》2011,43(3):476-476
Virus Genes - An error notified in the labelling of Fig.&;nbsp;1b, 3′tAC1 has been erroneously published as 5′tAC1.  相似文献   
1000.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号