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   8612篇
  免费   490篇
  国内免费   36篇
耳鼻咽喉   65篇
儿科学   206篇
妇产科学   96篇
基础医学   957篇
口腔科学   303篇
临床医学   557篇
内科学   2063篇
皮肤病学   122篇
神经病学   979篇
特种医学   659篇
外科学   1537篇
综合类   24篇
预防医学   236篇
眼科学   101篇
药学   491篇
中国医学   10篇
肿瘤学   732篇
  2023年   52篇
  2021年   122篇
  2020年   88篇
  2019年   107篇
  2018年   157篇
  2017年   111篇
  2016年   140篇
  2015年   146篇
  2014年   189篇
  2013年   223篇
  2012年   376篇
  2011年   388篇
  2010年   253篇
  2009年   201篇
  2008年   317篇
  2007年   420篇
  2006年   378篇
  2005年   374篇
  2004年   331篇
  2003年   307篇
  2002年   328篇
  2001年   332篇
  2000年   310篇
  1999年   317篇
  1998年   175篇
  1997年   145篇
  1996年   145篇
  1995年   113篇
  1994年   110篇
  1993年   108篇
  1992年   197篇
  1991年   190篇
  1990年   167篇
  1989年   201篇
  1988年   172篇
  1987年   185篇
  1986年   184篇
  1985年   157篇
  1984年   97篇
  1983年   93篇
  1982年   47篇
  1981年   49篇
  1980年   43篇
  1979年   66篇
  1978年   58篇
  1977年   59篇
  1976年   44篇
  1975年   39篇
  1973年   37篇
  1970年   36篇
排序方式: 共有9138条查询结果,搜索用时 15 毫秒
1.
Objective Pegylated-interferon monotherapy is the standard treatment for patients with chronic hepatitis B; however, the factors associated with its therapeutic effects remain unclear. Methods Patients with chronic hepatitis B were treated with pegylated interferon α-2a for 48 weeks. We evaluated the kinetics of hepatitis B surface antigen (HBsAg) during treatment and follow-up periods and the factors associated with an HBsAg response (defined as a change in HBsAg of ≥-1 log IU/mL from baseline). Results The study population comprised 50 patients. The median baseline levels of hepatitis B virus DNA and HBsAg were 5.00 and 3.40 log IU/mL. The median values of HBsAg reduction from baseline were -0.44 (n=48), -0.41 (n=40), and -0.68 (n=11) log IU/mL at the end of treatment and at 48 and 144 weeks post-treatment, respectively. The rates of HBsAg response were 24.0% and 22.5% at the end of treatment and at 48 weeks post-treatment, respectively. A multivariate analysis identified HBsAg <3.00 log IU/mL as an independent baseline factor contributing to the HBsAg response at the end of treatment and 48 weeks post-treatment (p=1.07×10-2 and 4.42×10-2, respectively). There were significant differences in the reduction of the HBsAg levels at 12 weeks of treatment and in the incidence of serum ALT increase during treatment between patients with and without an HBsAg response. Conclusion These findings suggest that the baseline HBsAg level, HBsAg kinetics at 12 weeks of treatment, and ALT increase during treatment are important factors contributing to the HBsAg response in pegylated interferon α-2a monotherapy for patients with chronic hepatitis B.  相似文献   
2.
3.
4.
5.
6.
7.
Histiocytic sarcoma (HS) is a rare hematopoietic tumor that mainly involves extranodal sites, including the intestinal tract, skin, soft tissues and other organs. It is well known as an aggressive neoplasm that shows a poor response to therapy. However, a subset of patients with resectable disease has shown a favorable outcome with surgical treatment. Primary cutaneous HS is exceedingly rare and, to date, its long-term prognosis has thus not been well described. Here, we highlight two cases of primary cutaneous HS that showed long-term survival. Case 1 was a healthy 47-year-old woman who found a 12-mm tumor on her forehead. Case 2 was a 66-year-old woman, under follow up of a myxoid liposarcoma in her leg, who presented with a 25-mm tumor in her hypothenar eminence. Histologically, the tumors in both cases had a smooth outline with proliferating atypical tumor cells that showed histiocytic differentiation as revealed by immunohistochemistry with antibodies to CD68 (KP-1) and lysozyme in case 1; and CD68, lysozyme and CD163 in case 2. Tumor cells in case 1 had a monotonous appearance. After complete resection, cases 1 and 2 have survived for 10 and 4 years, respectively, without recurrence. To date, such patients are relatively long follow-up cases of survival from HS and highlight how a clear outline of the primary cutaneous HS tumor may be associated with its resectability and be an important factor in the assessment of its curability.  相似文献   
8.
Upon infection or brain damage, microglia are activated to play roles in immune responses, including phagocytosis and soluble factor release. However, little is known whether the event of phagocytosis could be a trigger for releasing soluble factors from microglia. In this study, we tested if microglia secrete a neurovascular mediator matrix metalloproteinase-9 (MMP-9) after phagocytosis in vitro. Primary microglial cultures were prepared from neonatal rat brains. Cultured microglia phagocytosed Escherichia coli bioparticles within 2 hr after incubation and started to secrete MMP-9 at around 12 hr after the phagocytosis. A TLR4 inhibitor TAK242 suppressed the E. coli-bioparticle-induced MMP-9 secretion. However, TAK242 did not change the engulfment of E. coli bioparticles in microglial cultures. Because lipopolysaccharides (LPS), the major component of the outer membrane of E. coli, also induced MMP-9 secretion in a dose–response manner and because the response was inhibited by TAK242 treatment, we assumed that the LPS-TLR4 pathway, which was activated by adhering to the substance, but not through the engulfing process of phagocytosis, would play a role in releasing MMP-9 from microglia after E. coli bioparticle treatment. To support the finding that the engulfing step would not be a critical trigger for MMP-9 secretion after the event of phagocytosis in microglia, we confirmed that cell debris and amyloid beta were both captured into microglia via phagocytosis, but neither of them induced MMP-9 secretion from microglia. Taken together, these data demonstrate that microglial response in MMP-9 secretion after phagocytosis differs depending on the types of particles/substances that microglia encountered.  相似文献   
9.
10.
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