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   8792篇
  免费   615篇
  国内免费   301篇
耳鼻咽喉   56篇
儿科学   85篇
妇产科学   69篇
基础医学   1660篇
口腔科学   471篇
临床医学   793篇
内科学   1209篇
皮肤病学   207篇
神经病学   1300篇
特种医学   285篇
外国民族医学   3篇
外科学   617篇
综合类   1101篇
现状与发展   3篇
预防医学   394篇
眼科学   63篇
药学   562篇
  12篇
中国医学   166篇
肿瘤学   652篇
  2024年   17篇
  2023年   106篇
  2022年   205篇
  2021年   271篇
  2020年   271篇
  2019年   234篇
  2018年   239篇
  2017年   270篇
  2016年   274篇
  2015年   337篇
  2014年   546篇
  2013年   561篇
  2012年   404篇
  2011年   559篇
  2010年   437篇
  2009年   476篇
  2008年   530篇
  2007年   473篇
  2006年   474篇
  2005年   388篇
  2004年   340篇
  2003年   324篇
  2002年   228篇
  2001年   202篇
  2000年   174篇
  1999年   119篇
  1998年   131篇
  1997年   125篇
  1996年   134篇
  1995年   106篇
  1994年   81篇
  1993年   88篇
  1992年   89篇
  1991年   58篇
  1990年   62篇
  1989年   43篇
  1988年   36篇
  1987年   39篇
  1986年   35篇
  1985年   42篇
  1984年   30篇
  1983年   16篇
  1982年   28篇
  1981年   13篇
  1980年   22篇
  1979年   15篇
  1978年   7篇
  1977年   9篇
  1976年   14篇
  1971年   7篇
排序方式: 共有9708条查询结果,搜索用时 15 毫秒
1.
Breast core biopsies are a standard component of the triple approach that includes clinical examination, imaging and tissue sampling. Conventional cores, diagnostic vacuum assisted biopsy and vacuum assisted excisions are established methods for sampling and managing breast lesions. It is important to be aware of the potential pitfalls in the technical handling and interpretation of the limited core biopsy samples. Here, we present a clinically oriented, well illustrated overview of the common diagnostic pitfalls based on the author's diagnostic and second opinion practice, emphasize the value of clinicopathological correlation and provide histological tips and clues with useful immunohistochemistry to aid the reporting pathologists in their daily interpretation of breast core biopsies.  相似文献   
2.
Breast pseudoaneurysms after a core needle biopsy are a rare complication with a low incidence. However, it is important to be aware of the possibility of complications that require treatment.  相似文献   
3.
4.
5.
6.
A developmental validation was performed to demonstrate reliability, reproducibility and robustness of the ANDE System with the FlexPlex assay, including an integrated Expert System, across a number of laboratories and buccal sample variations. Previously, the related DNAscan™/ANDE 4C Rapid DNA System using the PowerPlex®16 assay and integrated Expert System Software received NDIS approval in March 2016. The enhanced ANDE instrument, referred to as ANDE 6C, and the accompanying 6-dye, 27-locus STR assay, referred to as FlexPlex, have been developed to be compatible with all widely used global loci, including the expanded set of the CODIS core 20 loci.Six forensic and research laboratories participated in the FlexPlex Rapid DNA developmental validation experiments, testing a total of 2045 swabs, including those obtained from 1387 unique individuals. The goal of this extensive and comprehensive validation was to thoroughly evaluate and document the ANDE System and its internal Expert System to reliably genotype reference buccal swab samples in a manner compliant with the FBI’s Quality Assurance Standards and the NDIS Operational Procedures.The ANDE System, including automated Expert System analysis, generated reproducible and concordant results for buccal swabs when testing various instruments at different laboratories by a number of different operators. When testing a number of non-human DNAs, including oral bacteria, the ANDE System and FlexPlex assay demonstrated limited cross-reactivity. Potential PCR inhibitors were evaluated as part of the validation and no inhibition was detected. Reproducible and concordant profiles were generated from buccal swab samples collected with a limit of detection appropriate for buccal swab collections from arrestees. The precision and resolution of the System met industry standards for detection of microvariants and single base resolution.The integrated Expert System appropriately demonstrated the ability to correctly pass or fail profiles for CODIS upload without human review. During this comprehensive developmental validation, the ANDE System successfully interpreted over 2000 samples tested with over 99.99% concordant alleles. The data package described herein led to the ANDE System with the FlexPlex assay receiving NDIS approval in June 2018.  相似文献   
7.
8.
9.
Gorlin syndrome (naevoid basal cell carcinoma syndrome) is a genetically linked disorder characterized by the development of multiple basal cell carcinomas (BCCs) throughout life. Cumulative surgery, cryotherapy and other conventional interventions can result in significant disfigurement by middle age. Radiotherapy is contra-indicated because the mutated gene underlying the syndrome, ‘PTCH’, increases sensitivity to ionising radiation, so there is significant likelihood of inducing further tumours in and around the irradiated area. Photodynamic therapy offers a non-invasive treatment option for patients with this condition, with the added advantage of causing minimal scarring.  相似文献   
10.
The use of livers from anti-hepatitis B core (HBc) positive donors can alleviate donor shortage. Nineteen of 367 (6%) adults receiving anti-HBc positive allografts [three were hepatitis B antigen (HBsAg) negative, hepatitis B antibody (HBsAb) positive; four were HBsAg positive and 12 were not exposed to hepatitis B viral (HBV) infection] were retrospectively reviewed. In HBsAg negative recipients, immunoprophylaxis (IP) was guided by viral serology and immunohistochemistry (IH) of day 0 and day 7 liver biopsies. If IH was negative, IP was stopped. None of three HBsAg negative, HBsAb positive recipients infected; one (replicating) of four HBsAg positive recipients reinfected and seven of eight (87.5%) HBsAg, HBsAb negative recipients, who did not receive long-term IP, infected after a median time of 2 years (range 1-5); one patient died of liver failure. Four HBsAg, HBsAb negative recipients, receiving life-long IP, remained infection free. Anti-HBc positive donor livers must be directed selectively first to HBsAg positive recipients, next to recipients having HBV antibodies and finally to HBV-naive recipients. Identification of both donor and recipient risk factors for HBV infection before transplantation allows indiscriminate use of antiviral prophylaxis. The necessity for IP therapy should be guided by HBV-DNA testing of donor liver tissue and serum. IH of early liver biopsies is an unreliable marker for predicting antiviral treatment requirements.  相似文献   
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