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   6474篇
  免费   377篇
  国内免费   41篇
耳鼻咽喉   309篇
儿科学   92篇
妇产科学   66篇
基础医学   1000篇
口腔科学   120篇
临床医学   382篇
内科学   1461篇
皮肤病学   87篇
神经病学   666篇
特种医学   216篇
外科学   872篇
综合类   61篇
预防医学   225篇
眼科学   54篇
药学   610篇
中国医学   18篇
肿瘤学   653篇
  2023年   34篇
  2022年   73篇
  2021年   164篇
  2020年   85篇
  2019年   99篇
  2018年   130篇
  2017年   104篇
  2016年   130篇
  2015年   103篇
  2014年   167篇
  2013年   193篇
  2012年   288篇
  2011年   372篇
  2010年   168篇
  2009年   159篇
  2008年   279篇
  2007年   289篇
  2006年   291篇
  2005年   312篇
  2004年   331篇
  2003年   288篇
  2002年   265篇
  2001年   243篇
  2000年   241篇
  1999年   207篇
  1998年   72篇
  1997年   73篇
  1996年   81篇
  1995年   57篇
  1994年   65篇
  1993年   57篇
  1992年   158篇
  1991年   146篇
  1990年   141篇
  1989年   121篇
  1988年   119篇
  1987年   113篇
  1986年   113篇
  1985年   96篇
  1984年   68篇
  1983年   54篇
  1982年   33篇
  1981年   24篇
  1980年   22篇
  1979年   39篇
  1978年   27篇
  1977年   27篇
  1974年   23篇
  1973年   18篇
  1971年   20篇
排序方式: 共有6892条查询结果,搜索用时 15 毫秒
1.

Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  相似文献   
2.
Clinical and Experimental Nephrology - The association between N-terminal pro-brain natriuretic peptide (NT-proBNP) and stroke in Japanese hemodialysis (HD) outpatients is unclear. Therefore, in...  相似文献   
3.
4.
From January 1986 to December 1988, a prospective trial of transcatheter arterial treatment was carried out for hepatocellular carcinoma (HCC). Two hundred seventy-five patients were included. Okuda's staging system was employed. Patients with Stage I and II HCC were treated by transcatheter arterial embolization (TAE) with a gelatin sponge containing an anti-cancer agent (protocol 1a); a gelatin sponge and iodized oil mixed with an anti-cancer agent (protocol 1b); or iodized oil mixed with an anti-cancer agent (protocol 2). Patients with Stage III HCC were treated with iodized oil with anti-cancer agent (protocol 2). As an exception, patients with an unsuccessful superselective catheterization into the proper hepatic artery by Seldinger technique or obstruction of the main trunk of the portal vein were treated with percutaneous transcatheter arterial infusion into the common hepatic artery regardless of stage (protocol 3). Tumor type and extension, area of tumor involvement, portal vein involvement, method of treatment, and presence of ascites and icterus were found to be the significant factors for an initial response to therapy. Treatment method was the most important factor. Respective survival rates at 1 and 2 years were 70.9% and 55.3% for protocol 1a; 62.3% and 43.8% for protocol 1b; 37.8% and 18.3% for protocol 2; and 16.5% and 0% for protocol 3. Many factors proved to significantly influenced prognosis; however, tumor type had the most important prognostic significance followed by AFP value, ascites, treatment protocol, and area of tumor involvement.  相似文献   
5.
S Kakizoe  M Kojiro  T Nakashima 《Cancer》1987,59(2):310-316
Among 355 autopsy cases of hepatocellular carcinoma (HCC), 14 cases exhibited sarcomatous appearance (incidence, 3.9%). A clinicopathologic study was performed in these 14 cases, and the immunohistochemical localization of keratin (KRT), vimentin (VMT), albumin (ALB), fibrinogen (FBG) and alpha-fetoprotein (AFP) was also examined using the avidin-biotin complex method. Clinically, the HCCs with sarcomatous appearance were characterized by negative or low serum AFP levels and high incidence of extrahepatic metastasis. Grossly they were of infiltrative, mixed expansive and infiltrative, and pedunculated types. Histologically, the tumor consisted mainly of spindle-shaped cells and partly of multinucleated cells, and showed a sinusoidal growth pattern at the tumor-nontumor boundary. Immunohistochemically, tumor cells in the regions showing sarcomatous appearance were frequently found to be positive to KRT and VMT, whereas the percentage of positivity to ALB, FBG, and AFP were not significantly different from those in ordinary HCC. These results strongly suggest that the lesion showing sarcomatous appearance represents the sarcomatous change of HCC rather than being regarded as the complication of HCC and sarcoma.  相似文献   
6.
7.
Patients with head injury may experience olfactory dysfunction. Unfortunately, little is known about changes in the olfactory neuroepithelium caused by intracranial olfactory nerve injury and hemorrhage. We performed olfactory nerve section or bulbectomy in 53 Mongolian gerbils and subjected the olfactory neuroepithelium to immunohistochemical analysis. A decrease or disappearance of the antiserum to an olfactory marker protein containing olfactory receptor neurons was evident in the sectioned group. Degeneration of the olfactory neuroepithelium contralateral to olfactory nerve injury was also noted in animals with perineural hemorrhage. These findings suggest that olfactory dysfunction may occur not only with nerve injury but also secondary to intracranial hemorrhage.  相似文献   
8.
Neoplastic angioendotheliosis has rarely been described as a respiratory disease. A patient is described with pulmonary vascular involvement induced by neoplastic angioendotheliosis in pulmonary vessels.  相似文献   
9.
Spinal cord compression is an extremely serious complication of hereditary multiple exostoses (HME). A case of HME with compression of the cervical spinal cord is reported. Complete recovery following surgery was achieved. A review of the relevant literature revealed 51 previous cases of HME with cord/cauda equina compression. Most patients were under 30 years of age with more men affected than women. The family history was positive in 60%. The cervical and thoracic areas were predominantly affected, with the symptoms usually developing slowly. Recovery following surgery is to be expected in the majority of cases. In patients with HME and suffering from neurological symptoms, the possibility of spinal cord compression should be considered. Prompt diagnosis and surgical excision provide the best prognosis.  相似文献   
10.
Our aim was to find a simple method of removing labile glycosylated hemoglobin (HbA1c) from blood samples before it is measured by cation-exchange chromatography. Labile HbA1c is formed by the binding of glucose to the NH2-terminal valine of the beta-chain of HbA. We sought a more competitive binder for the same site to dissociate labile HbA1c to glucose and HbA. Inorganic phosphates were found to have a strong allosteric effect and a great ability to eliminate labile HbA1c. We developed our method with 4 mM tetrapolyphosphate in the hemolyzing solution to eliminate labile HbA1c during the automatic processing (at pH 6 and heated for 2 min at 45 degrees C) of blood samples for HbA1c estimation. This may be useful when estimating HbA1c by the manual method.  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