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   636篇
  免费   37篇
  国内免费   1篇
耳鼻咽喉   2篇
儿科学   15篇
妇产科学   13篇
基础医学   46篇
口腔科学   21篇
临床医学   109篇
内科学   155篇
皮肤病学   37篇
神经病学   12篇
特种医学   88篇
外国民族医学   1篇
外科学   47篇
综合类   37篇
预防医学   21篇
眼科学   2篇
药学   42篇
中国医学   1篇
肿瘤学   25篇
  2022年   16篇
  2021年   13篇
  2020年   9篇
  2019年   13篇
  2018年   15篇
  2017年   11篇
  2016年   9篇
  2015年   15篇
  2014年   19篇
  2013年   20篇
  2012年   8篇
  2011年   14篇
  2010年   32篇
  2009年   28篇
  2008年   9篇
  2007年   11篇
  2006年   16篇
  2005年   10篇
  2004年   7篇
  2003年   11篇
  2002年   6篇
  1999年   7篇
  1998年   21篇
  1997年   13篇
  1996年   24篇
  1995年   18篇
  1994年   25篇
  1993年   28篇
  1992年   13篇
  1991年   6篇
  1989年   17篇
  1988年   14篇
  1987年   8篇
  1986年   8篇
  1985年   14篇
  1983年   9篇
  1982年   10篇
  1981年   9篇
  1980年   11篇
  1979年   11篇
  1978年   7篇
  1977年   9篇
  1976年   6篇
  1975年   6篇
  1974年   7篇
  1957年   9篇
  1955年   6篇
  1954年   6篇
  1949年   8篇
  1948年   8篇
排序方式: 共有674条查询结果,搜索用时 15 毫秒
671.
In vitro culture of day-15.5 murine fetal liver (FL) cells in the presence of recombinant interleukin-2 (IL-2) results in the expansion of Fc gamma RII/III+ CD3-Ti-NK1.1+ cells displaying both natural killer (NK) and antibody-dependent cell cytotoxicity (ADCC) cytolytic activities. These FL-derived NK cells express Fc gamma RIII (CD16) in association with an Fc epsilon RI gamma homodimer on their surface. In contrast, in vitro expansion of FL cells in the absence of IL-2 generates noncytotoxic cells belonging to the myelomonocytic lineage (Mac1+Gr1+NK1.1-). Hence, IL-2 appears to be critical for the proliferation and differentiation of NK cells from FL progenitors. Experiments in which FL cells were fractionated by density gradient centrifugation before in vitro expansion showed that NK progenitors are contained within a cell population with a density of 1.04 < d < 1.08 g/mL. Cells with d > 1.08 g/mL (representing > or = 40% of FL cells) have no such NK progenitor activity. In addition, after intrathymic injection into Ly5 congenic host animals, day-15.5 CD4-CD8- FL cells mature into CD4+CD8+ thymocytes within 12 days. Interestingly, this T- cell progenitor activity is restricted to subpopulations of FL cells that also contain NK progenitors, but is absent in high-density (d > 1.08 g/mL) FL cells. Finally, fractionation of FL cells according to surface expression of Fc gamma RII/III complexes shows that NK (and T- lymphocyte) progenitors are found in both Fc gamma RII/III+ and Fc gamma RII/III-FL subpopulations.  相似文献   
672.
Bronchopulmonary cancer muscle metastases are uncommon, especially when they are visible. They can impact any muscle in the body, but the psoas, diaphragmatic, and paravertebral muscles have a clear advantage. We present a case of lateral pterygoid muscle metastasis of squamous cell carcinoma of the lung in a 70-year-old habitual smoker (40 packs per year) presents headaches more marked on the right and progressively worsening. A complementary brain MRI revealed a well-limited oval formation with irregular contours in hypo signal T1 hyper signal T2 heterogeneous, with area of central necrosis of the right pterygoid muscle, which was revealed to be a secondary location of bronchopulmonary malignancy after further examination (CT scan of the cervico-thoraco-abdomino-pelvic region, TEP scan, and biopsy). Moreover, muscle metastases are rarely revealing of primary cancer.  相似文献   
673.
Post-traumatic hepatic biloma is a rare complication of closed trauma of the abdomen. Generally, biloma occurs spontaneously or secondary to traumatic or iatrogenic injury to the biliary system. It can lead to significant morbidity and mortality if not diagnosed promptly and properly managed. A 4-year-old child was admitted to the emergency room with abdominal pain following a traffic accident. Clinical examinations suspected closed abdominal trauma without biological signs of icteric cholestasis. Abdominal CT scan performed within 24 hours showed a focus of hepatic laceration, and follow-up imaging at 5 days showed post-traumatic intrahepatic cystic formations. This case report aims to emphasize the importance of imaging including ultrasound, CT, MRI, MRI cholangiopancreatography (MRCP), or hepatobiliary cholescintigraphy to establish the diagnosis and guide the therapeutic gestures.  相似文献   
674.
Mediastinal bronchial artery aneurysm is very rare and only few cases have been reported in the literature. The clinical presentations are varied, ranging from an incidental radiological finding to a cataclysmic rupture leading to hemorrhagic shock. Thus, a quick treatment is indicated upon diagnosis. Therapeutic options are various including surgical resection, stent grafting with percutaneous embolization of feeding vessel or transtarterial embolization. Herein we describe a case of an incidental mediastinal bronchial artery aneurysm in a 63-year-old man, managed by transtarterial embolization.  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