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   6384篇
  免费   562篇
  国内免费   240篇
耳鼻咽喉   101篇
儿科学   221篇
妇产科学   161篇
基础医学   591篇
口腔科学   161篇
临床医学   681篇
内科学   1128篇
皮肤病学   125篇
神经病学   239篇
特种医学   184篇
外科学   1072篇
综合类   770篇
一般理论   1篇
预防医学   365篇
眼科学   199篇
药学   604篇
  2篇
中国医学   313篇
肿瘤学   268篇
  2024年   39篇
  2023年   111篇
  2022年   255篇
  2021年   334篇
  2020年   239篇
  2019年   204篇
  2018年   219篇
  2017年   242篇
  2016年   229篇
  2015年   288篇
  2014年   335篇
  2013年   397篇
  2012年   522篇
  2011年   487篇
  2010年   358篇
  2009年   310篇
  2008年   425篇
  2007年   390篇
  2006年   335篇
  2005年   334篇
  2004年   238篇
  2003年   262篇
  2002年   189篇
  2001年   108篇
  2000年   94篇
  1999年   55篇
  1998年   23篇
  1997年   28篇
  1996年   17篇
  1995年   19篇
  1994年   20篇
  1993年   15篇
  1992年   6篇
  1991年   13篇
  1990年   7篇
  1989年   4篇
  1988年   4篇
  1987年   7篇
  1985年   6篇
  1984年   2篇
  1983年   3篇
  1982年   3篇
  1976年   1篇
  1974年   1篇
  1971年   1篇
  1968年   1篇
  1966年   1篇
  1965年   2篇
  1957年   1篇
  1943年   1篇
排序方式: 共有7186条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
995.
Girdin has been proven to play a vital role in the process of proliferation, apoptosis, and invasion in various cancer cells, yet the underlying molecular mechanism in primary hepatocellular carcinoma (HCC) has not yet been clarified. Thereafter, we performed immunohistochemistry to detect the expression of Girdin in 40 primary HCC tissues and 30 matched adjacent tissues using hepatic carcinoma tissue microarray. Our data showed that the positive expression rate of Girdin in hepatocellular carcinoma tissues was 67.5%, higher than that found in adjacent tissues of 16.7% (P < 0.05). It closely correlates to tumor size, T stage, TNM stage and Edmondson-Steiner stage (P < 0.05) of HCC patients. After specific small interfering RNA of Girdin was transfected into HepG2 and Huh7.5.1 cells, the proliferation and invasion ability of tumor cells were significantly inhibited. In summary, we suggest that the oncogenic role of Girdin could provide new molecular target for the treatment of HCC.  相似文献   
996.
Since the outbreak of 2019 novel coronavirus (SARS-CoV-2) pneumonia, many patients with underlying disease, such as interstitial lung disease (ILD), were admitted to Tongji hospital in Wuhan, China. To date, no data have ever been reported to reflect the clinical features of Corona Virus Disease 2019 (COVID-19) among these patients with preexisting ILD. We analyzed the incidence and severity of COVID-19 patients with ILD among 3201 COVID-19 inpatients, and compared two independent cohorts of COVID-19 patients with pre-existing ILD (n = 28) and non-ILD COVID-19 patients (n = 130). Among those 3201 COVID-19 inpatients, 28 of whom were COVID-19 with ILD (0.88%). Fever was the predominant symptom both in COVID-19 with ILD (81.54%) and non-ILD COVID-19 patients (72.22%). However, COVID-19 patients with ILD were more likely to have cough, sputum, fatigue, dyspnea, and diarrhea. A very significantly higher number of neutrophils, monocytes, interleukin (IL)-8, IL-10, IL-1β, and D-Dimer was characterized in COVID-19 with ILD as compared to those of non-ILD COVID-19 patients. Furthermore, logistic regression models showed neutrophils counts, proinflammatory cytokines (tumor necrosis factor-alpha, IL6, IL1β, IL2R), and coagulation dysfunction biomarkers (D-Dimer, PT, Fbg) were significantly associated with the poor clinical outcomes of COVID-19. ILD patients could be less vulnerable to SARS-CoV-2. However, ILD patients tend to severity condition after being infected with SARS-CoV-2. The prognosis of COVID-19 patients with per-existing ILD is significantly worse than that of non-ILD patients. And more, aggravated inflammatory responses and coagulation dysfunction appear to be the critical mechanisms in the COVID-19 patients with ILD.  相似文献   
997.
998.
Hyperspectral image compression is an important task, where the aim is to store or transmit data in an efficient way. Hyperspectral images are mostly captured by a sensor system that includes multiple imaging sensors covering different regions of the electromagnetic spectrum. Misalignment of multiple imaging sensors produces boresight effect, and this problem can degrade band prediction performance noticeably. Another problem is prediction of blurry band images. In order to gain robustness to these problems, bimodal conventional recursive least-squares (B-CRLS) prediction method is proposed for the lossless compression of hyperspectral images. Two prediction modes are defined: spectral and spatio-spectral. B-CRLS method has a two-step process. First, mode selection is carried out for each band. Afterwards, final band image is predicted by using the selected mode, and the residual images are encoded with an arithmetic encoder. The proposed method is compared to adaptive-length CRLS, fixed-length CRLS, and other well-known prediction methods. Experiments have been performed on uncalibrated and calibrated hyperspectral images. Obtained results show that the proposed method achieves competitive compression performance with the state-of-the-art while providing relatively lower-computation times.  相似文献   
999.
目的研究麻黄细辛附子汤(MXF)干预肾阳虚外感小鼠的药效作用及其对正常小鼠的毒性作用差异,并考察其效-毒作用机制。方法BABL/C雄性小鼠随机分为正常组、正常毒性低、中、高剂量组;肾阳虚外感模型组;肾阳虚外感低、中、高剂量组,连续灌胃给药6 d,记录体重、肛温等药理指标并观察小鼠的一般体征,检测生化指标、炎症因子。结果药效实验中,与正常组小鼠相比,肾阳虚外感模型组小鼠生化指标肌酸激酶(CK)、肌酸激酶-同工酶(CK-MB)、羟丁酸脱氢酶(α-HBDH)、乳酸盐脱氢酶(LDH)、丙氨酸氨基转移酶(ALT)、天冬氨酸转移酶(AST)、碱性磷酸酶(ALP)、尿素(urea)含量明显升高(P<0.05),炎症因子白介素-6(IL-6)、单核细胞去化蛋白(MCP-1)、肿瘤坏死因子-α(TNF-α)、白介素-10(IL-10)、干扰素-γ(INF-γ)以及白介素12(IL-12p70)含量升高明显(P<0.05)。经给药治疗后,各给药组CK、ALT、urea等生化指标含量较模型组有所回调,各给药组IL-6、IL-10、IFN-γ等炎症因子含量较模型组有不同程度的回调;毒性研究中,各给药组生化指标CK、urea、半胱氨酸(CYS-C)的含量较正常组显著升高(P<0.05),炎症因子白介素-10(IL-10)含量明显上升、白介素-12(IL-12p70)含量明显下降(P<0.05)。结论经MXF给药治疗后,肾阳虚外感给药组小鼠的一些生化指标均有不同程度的回调,MXF可通过调节IL-6、IL-10、IFN-γ、MCP-1、肿瘤坏死因子-α(TNF-α)等炎症因子改善机体的炎症反应;而正常小鼠给予不同剂量的MXF后心脏、肝脏和肾脏功能出现失调,机体通过细胞转移、打破免疫应答的平衡,从而使正常小鼠出现炎症反应。  相似文献   
1000.
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