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   4999篇
  免费   682篇
  国内免费   170篇
耳鼻咽喉   48篇
儿科学   38篇
妇产科学   178篇
基础医学   2173篇
口腔科学   62篇
临床医学   281篇
内科学   316篇
皮肤病学   25篇
神经病学   79篇
特种医学   54篇
外国民族医学   4篇
外科学   347篇
综合类   669篇
预防医学   187篇
眼科学   167篇
药学   131篇
中国医学   34篇
肿瘤学   1058篇
  2024年   11篇
  2023年   47篇
  2022年   82篇
  2021年   154篇
  2020年   181篇
  2019年   215篇
  2018年   156篇
  2017年   226篇
  2016年   237篇
  2015年   229篇
  2014年   323篇
  2013年   322篇
  2012年   287篇
  2011年   302篇
  2010年   276篇
  2009年   284篇
  2008年   247篇
  2007年   243篇
  2006年   231篇
  2005年   194篇
  2004年   198篇
  2003年   169篇
  2002年   164篇
  2001年   117篇
  2000年   44篇
  1999年   56篇
  1998年   144篇
  1997年   117篇
  1996年   90篇
  1995年   53篇
  1994年   40篇
  1993年   46篇
  1992年   35篇
  1991年   43篇
  1990年   34篇
  1989年   30篇
  1988年   36篇
  1987年   37篇
  1986年   35篇
  1985年   32篇
  1984年   12篇
  1983年   12篇
  1982年   11篇
  1981年   9篇
  1980年   4篇
  1979年   6篇
  1978年   14篇
  1977年   3篇
  1976年   7篇
  1975年   4篇
排序方式: 共有5851条查询结果,搜索用时 31 毫秒
111.
Lung cancer is the leading cause of cancer deaths worldwide, and has one of the lowest survival rates of any solid tumor. In recent years, several attempts have been conducted to improve an early or accelerated diagnosis due to better overall prognosis after therapy. The aim of this study was evaluating the use of genetic markers for diagnosis of lung cancer. This study was conducted in accordance to Transparent Reporting of Systematic Reviews and Meta‐Analyses. Three Internet sources were used to search: MEDLINE‐PubMed, EMBASE, and LILACS. The databases were searched for studies conducted in the period up to and including May 10, 2011. The following inclusion criteria were applied: lung cancer studies, and the use of genetic markers for diagnosis. Studies using animal models, review articles, meta‐analyses, abstracts, conference proceedings, editorials/letters, case reports, incorrect study population, inadequate data, and cytology was not obtained, were excluded. A total of 1,901 abstracts/citations were identified for preliminary review. From 24 final selected studies, 17 referred to chromosomal markers diagnosis, eight to genes as marker, and one to both subjects. Fluorescence in situ hybridization (FISH) was applied in all studies. Despite the limitations of this study, application of genetic markers to lung cancer diagnosis seems to have prognosis value irrespective of detection methodology used. FISH was the main technique applied to diagnose genetics alterations and revealed a high specificity, although some authors reported low sensitivity. Diagn. Cytopathol. 2013;41:834–842. © 2013 Wiley Periodicals, Inc.  相似文献   
112.
113.
114.
Papillary carcinoma is the most common thyroid malignancy. As the cytological diagnosis of papillary carcinoma is not difficult in patients with the usual type of lesion, fine‐needle aspiration (FNA) cytology is an effective method for preoperative evaluation. However, this modality is often ineffective in identifying the follicular variant of papillary thyroid carcinoma (FVPTC) due to its similarity to other follicular lesions and the incompleteness of typical nuclear features. Therefore, we investigated the expression of immunocytochemical markers of papillary carcinoma in cytological specimens of FVPTC and evaluated their utilities. The immunoreactivity of HBME‐1 and CD15 was investigated using 50 imprint smear cytological specimens obtained from thyroid lesions, including 13 FVPTC. The sensitivity and specificity of HBME‐1 for FVPTC were 92% and 89%, respectively, while those of CD15 were 23% and 100%, respectively. In conclusion, HBME‐1 is a sensitive marker of papillary carcinoma, including both usual type and FVPTC, in cytological specimens. Therefore, using HBME‐1 immunocytochemistry in FNA cytology will lead to reduction of the incidence of false‐negative diagnoses of FVPTC. Although CD15 is apparently inferior in terms of sensitivity for FVPTC, its excellent specificity will support the definitive diagnosis of thyroid malignancies, including FVPTC, after screening with HBME‐1.  相似文献   
115.
116.
目的:了解象山海岛地区农(渔)村妇女宫颈疾病的发病状况,提高宫颈癌的早诊和早治率,提升广大农(渔)村妇女的自我保健意识和健康水平。方法采用妇科内诊检查,采集宫颈细胞进行液基薄层细胞学检查( TCT),对细胞学检查异常的患者进一步行阴道镜检查、人乳头瘤病毒( HPV)检测、宫颈组织病理学检查。结果通过妇科检查发现57.35%的农(渔)村妇女患有宫颈疾病,其中以宫颈糜烂发病率最高(21.35%);通过TCT检查发现宫颈细胞学异常发生率3.26%,癌前病变发生率120/万,宫颈癌发生率8.57/万。结论 TCT诊断结果采用TBS报告系统,对宫颈癌前病变的检出率高于传统的宫颈刮片巴氏细胞学报告。40~50岁的育龄妇女是宫颈癌的高发人群,持续感染HPV者是重点干预和检测的对象。应加强农(渔)村妇女的健康教育,提高其自我保健意识将有助于宫颈疾病的早期预防。  相似文献   
117.
目的探讨薄层液基细胞学(TCT)诊断意义不明确的不典型鳞状细胞(ASCUS)的患者细胞学与HC-Ⅱ检测、组织病理学诊断结果之间的相互关系,为提高宫颈癌早期筛查水平提供参考依据。方法 2010年11月至2013年11月于秦皇岛市妇幼保健院就诊的82 385例患者的宫颈细胞学检测标本中,对其中1 668例TCT诊断ASCUS患者进行HC-Ⅱ检测及组织病理学诊断。结果 82 385例标本中无上皮内病变或恶性病变(NILM)为97.25%(80 120/82 385);高级别鳞状上皮内病变(HSIL)213例(0.26%,213/82 385);低级别鳞状上皮内病变(LSIL)276例(0.34%,276/82 385);不除外高级别不典型鳞状细胞(ASC-H)73例(0.08%,73/82 385);意义不明确的不典型鳞状细胞(ASCUS)1 668例(2.02%,1 668/82 385);腺细胞异常(AGUS)35例(0.05%,35/82 385);细胞学ASCUS患者的HC-Ⅱ检测阳性率为68.41%(1 141/1 668);细胞学诊断为ASCUS,组织病理学对照分别为炎症性改变、湿疣/CINⅠ级、CINⅡ/Ⅲ级、浸润性鳞状细胞癌的比例依次为45.86%(765/1 668)、42.21%(704/1 668)、11.87%(198/1 668)、0.06%(1/1 668)。结论对ASCUS的形态学应进一步深入研究,并将高危型HPV检测与TCT检测技术相结合应用于早期宫颈癌及癌前病变筛查。  相似文献   
118.
Cytology is a powerful diagnostic tool but to make definitive diagnoses, the use of ancillary techniques is imperative. By combining immunohistochemistry (IHC) and electron microscopy (EM), cytologic diagnoses can be as precise as those of surgical pathology. In the authors' daily practice of cytopathology they use all ancillary techniques available to them: histochemistry, IHC, EM, flow cytometry, and molecular pathology. IHC is frequently used as an ancillary technique in their daily practice but EM is many times their technique of choice. By the use of EM the authors can make specific final diagnoses, make the diagnosis more definitive, narrow the differential diagnosis, or determine the origin of a neoplasm with unknown primary site. Specimens obtained by fine-needle aspiration as well as all body fluids are suitable for EM. The limiting factor is to obtain the appropriate material with the diagnostic cells for ultrastructural examination. The common diagnostic dilemmas in the everyday practice of cytology are the following: mesothelioma vs. adenocarcinoma, neuroendocrine differentiation or not, the distinction of melanoma from adenocarcinoma and sarcoma, hepatocellular carcinoma vs. adenocarcinoma, and the origin of adenocarcinomas of unknown primary. The authors discuss how they approach these diagnostic problems in their everyday practice and how they incorporate EM in solving them.  相似文献   
119.
Fine-needle aspiration cytology (FNAC) is an established, highly accurate, and cost-effective method for diagnosing lesions in different organs, including the breast. The method is minimally invasive without unwanted side effects. FNAC forms part of the triple assessment of breast lesions. Despite some shortcomings of the reporting categories, FNAC as part of the triple assessment has proved its value in describing the findings most accurately. The diagnostic impact depends on experience of the operator, quality of preparation, and diagnostic skills of the cytopathologist. The highest accuracy is achieved at centers with a multidisciplinary approach. FNAC is often palpation guided from palpable breast masses, whereas ultrasonography guidance is more widely used on nonpalpable lesions. Inadequate sampling with FNAC is particularly seen in collagenous lesions and in submitted specimens sampled by physicians lacking experience with the FNAC procedure. A diagnostic biopsy is recommended when FNAC provides scant material. FNAC is considered to be a safe method for screening purposes, although moderately less sensitive than core needle biopsy. FNAC is most accurate when experienced cytopathologists are available to assess the adequacy of the aspirated material and advise on additional aspirations for ancillary tests when needed.  相似文献   
120.
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