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   1264篇
  免费   132篇
  国内免费   21篇
耳鼻咽喉   12篇
儿科学   34篇
妇产科学   15篇
基础医学   177篇
口腔科学   40篇
临床医学   69篇
内科学   395篇
皮肤病学   127篇
神经病学   57篇
特种医学   49篇
外科学   114篇
综合类   13篇
预防医学   63篇
眼科学   16篇
药学   48篇
肿瘤学   188篇
  2024年   5篇
  2023年   14篇
  2022年   22篇
  2021年   20篇
  2020年   17篇
  2019年   22篇
  2018年   45篇
  2017年   58篇
  2016年   49篇
  2015年   55篇
  2014年   55篇
  2013年   48篇
  2012年   90篇
  2011年   102篇
  2010年   54篇
  2009年   38篇
  2008年   64篇
  2007年   77篇
  2006年   88篇
  2005年   93篇
  2004年   67篇
  2003年   75篇
  2002年   72篇
  2001年   12篇
  2000年   9篇
  1999年   16篇
  1998年   15篇
  1997年   8篇
  1996年   6篇
  1995年   8篇
  1994年   10篇
  1993年   4篇
  1992年   9篇
  1991年   8篇
  1990年   13篇
  1989年   8篇
  1988年   5篇
  1987年   6篇
  1986年   3篇
  1984年   10篇
  1983年   8篇
  1982年   2篇
  1981年   3篇
  1979年   2篇
  1978年   2篇
  1977年   4篇
  1969年   6篇
  1967年   2篇
  1966年   1篇
  1957年   1篇
排序方式: 共有1417条查询结果,搜索用时 15 毫秒
51.
52.
53.
54.

Background and Aim

Virologic failure of interferon‐free therapy has been associated with Y93H mutation in the non‐structure 5A region in hepatitis C virus (HCV) genotype 1b, and screening is recommended. A simple assay based on Q‐Invader technology was developed for Y93H mutant screening to reduce cost and effort. The present study sought to compare two methods of detection of Y93H mutation and to evaluate the effect of Y93H mutation on response to interferon‐free therapy.

Methods

Y93H mutation was examined in 258 patients with HCV genotype 1b using both direct sequencing analysis and the polymerase chain reaction (PCR)‐Invader assay. Daclatasvir and asunaprevir or ledipasvir and sofosbuvir therapy was administered to 205 patients whose sustained virological responses (SVR) were checked.

Results

Hepatitis C virus was detected in 232 of 258 patients by direct sequencing and in 236 of 258 patients by the PCR‐Invader assay. Forty of 231 cases were defined as Y93 mutation by direct sequencing, and 46 of 236 cases were defined as Y93 mutation by the PCR‐Invader assay. SVR of patients who were Y93H by direct sequencing, Y93H by the PCR‐Invader assay, and Y93H by both methods was 62.5%, 82.4%, and 50%, respectively.

Conclusions

The sensitivity of the PCR‐Invader assay was similar to that of direct sequencing analysis; however, the PCR‐Invader assay had a better ability to detect minor strains. Combination of the two assays would improve prediction of the response to daclatasvir and asunaprevir, but Y93H mutation had little effect on SVR in ledipasvir and sofosbuvir therapy.  相似文献   
55.
56.
57.

Background

It is controversial whether patients with gastric marginal zone lymphomas of mucosa associated lymphoid tissue (MALT) have higher risk of second malignancies. The aim of this study was to define the risk of second malignancies in these patients.

Methods

We analyzed prospective follow-up data of 146 consecutive patients with gastric MALT lymphoma treated at Aichi Cancer Center Hospital and compared the incidence of second malignancies with that in the general population. We calculated the standardized incidence ratio (SIR), using age- and sex-specific incidence rates from the Aichi Cancer Registry.

Results

The median follow-up period was 74 months. A total of 27 tumors occurred in 22 patients (15.1 %), including 19 solid tumors. Of these, nine tumors were detected concomitantly with, and 18 tumors following, the diagnosis of gastric MALT lymphoma. Four patients had two second malignancies each. For the entire group, the SIR of an additional malignancy was 3.39 (95 % confidence interval [CI] 2.11–4.66). An increased incidence of solid tumors (SIR 2.91 [1.60–4.22]) and hematologic malignancies (SIR 5.54 [1.70–9.38]) were seen. In addition, there was increased risk for development of second malignancies during follow up (SIR 2.26 [1.21–3.30]). Chemotherapy for treatment of MALT was an independent risk factor for second malignancies (age–sex adjusted hazard ratio 3.98 [1.47–10.79].

Conclusions

Compared with the general population, patients with gastric MALT lymphoma are at increased risk for second malignancies, including gastric cancer.  相似文献   
58.
Thrombotic microangiopathy (TMA) is associated with vascular endothelial cell injury and is sometimes linked with poor outcome. Von Willebrand factor (VWF) propeptide (VWFpp) is considered to be a marker of vascular endothelial cell injury. The plasma levels of VWF, VWFpp, and thrombomodulin (TM) were evaluated for their use in the diagnosis of TMA in 75 patients with TMA. There were 30 TMA patients with marked decreases in ADAMTS13 (TMA/ADAMTS13) and 45 without the decrease (TMA/other). The plasma levels of TM, VWF, and VWFpp values were significantly high in patients with TMA, especially TMA/other group. The plasma levels of TM and VWFpp were significantly high in non-survivor with TMA. In the TMA/other group, the plasma levels of VWFpp were negatively correlated with ADAMTS13 activity. The plasma levels of TM correlated with the renal function, but the plasma levels of VWFpp did not. A ROC analysis indicated that VWFpp and TM were useful markers for the prediction of a poor outcome. These findings suggest that VWFpp is an useful marker for the diagnosis of TMA and for the prediction of poor outcome.  相似文献   
59.
60.
Hepatitis B virus (HBV) has been classified into eight genotypes and can be further divided into several subgenotypes that have different geographic distributions. Because of increased human migration, the prevalence of rare subgenotypes is increasing in Japanese patients with acute hepatitis B. Lamivudine-resistant strains of HBV have begun to emerge in association with chronic hepatitis B. The aim of this study was to investigate the distribution of HBV subgenotypes and lamivudine-resistant strains in patients in Japan with acute hepatitis B. One hundred twenty-three patients with acute hepatitis B and 123 with chronic hepatitis B were studied. HBV subgenotypes and lamivudine-resistance mutations were determined by direct sequencing of the preS and polymerase region, respectively. HBV subgenotypes Aa (n=3), Ae (n=23), Ba (n=7), Bj (n=3), Cs (n=7), Ce (n=76), D (n=2), and H (n=2) were detected in patients with acute hepatitis. In patients with chronic hepatitis, HBV subgenotypes Ae (n=4), Ba (n=1), Bj (n=18), and Ce (n=100) were found. Non-common Japanese subgenotypes, that is, non-Bj and non-Ce, were detected more frequently in patients with acute hepatitis (35.8%) than in patients with chronic hepatitis (4.1%) (Odds ratio, 0.076; 95%CI, 0.029-0.200; P<0.0001). Lamivudine-resistance mutations were detected in chronic hepatitis patients with breakthrough hepatitis but not in other patients. In conclusion, the prevalence of uncommon Japanese HBV subgenotypes is expected to increase, although lamivudine-resistant strains have not yet been found in patients with acute hepatitis B.  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