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   601篇
  免费   21篇
  国内免费   5篇
耳鼻咽喉   3篇
儿科学   33篇
妇产科学   2篇
基础医学   88篇
口腔科学   18篇
临床医学   18篇
内科学   191篇
皮肤病学   5篇
神经病学   41篇
特种医学   11篇
外科学   69篇
综合类   5篇
预防医学   19篇
眼科学   5篇
药学   61篇
肿瘤学   58篇
  2022年   3篇
  2021年   8篇
  2020年   5篇
  2019年   5篇
  2018年   8篇
  2017年   6篇
  2016年   6篇
  2015年   9篇
  2014年   17篇
  2013年   22篇
  2012年   31篇
  2011年   37篇
  2010年   13篇
  2009年   13篇
  2008年   25篇
  2007年   34篇
  2006年   25篇
  2005年   31篇
  2004年   30篇
  2003年   33篇
  2002年   27篇
  2001年   27篇
  2000年   24篇
  1999年   18篇
  1998年   9篇
  1997年   16篇
  1996年   12篇
  1995年   7篇
  1994年   4篇
  1993年   3篇
  1992年   12篇
  1991年   20篇
  1990年   17篇
  1989年   11篇
  1988年   7篇
  1987年   10篇
  1986年   6篇
  1985年   7篇
  1984年   2篇
  1983年   4篇
  1981年   2篇
  1980年   2篇
  1979年   3篇
  1978年   3篇
  1977年   2篇
  1974年   1篇
  1972年   1篇
  1968年   1篇
  1966年   2篇
  1924年   3篇
排序方式: 共有627条查询结果,搜索用时 0 毫秒
81.
Secondary pinch skin grafting was performed on the mastoid cavities to promote healing of the mastoid wound after ear surgery using the open technique. Pinch grafts (multiple small grafts of the epidermal layer) were transplanted in 20 patients, soon after the mastoid cavities were covered with healthy granulation tissue in a mean of 28.5 days after the initial surgery. The grafts adapted well in 18 of the 20 patients. Epidermization was complete in a mean of 11.1 days after grafting, that is, within 40 days after the initial ear surgery. On the other hand, epidermization in 10 cases without grafting was completed in a mean of 83.3 days after the ear surgery. Thus, the pinch grafts reduced healing time by more than 40 days. The secondary application of pinch grafting was beneficial for healing of exposed mastoid cavities caused by use of the open technique tympanoplasty or radical mastoidectomy.  相似文献   
82.
83.
84.
Ohne ZusammenfassungAusführlicher mitgeteilt in den Berichten der medizinischen Gesellschaft Tokio (mit 15 Kurven), Bd. 34, S. 5 und 6.  相似文献   
85.
86.
Purpose. The effects of transfection with the human Cu, Zn-superoxide dismutase (hSOD)4 gene on active oxygen-induced cytotoxicity in rat skin fibroblasts (FR) were studied for the purpose of developing the novel delivery system of hSOD using hSOD gene. Methods. An expression plasmid for hSOD, pRc/RSV-SOD, was constructed and used to transfect FR cells. Xanthine (X)/xanthine oxidase (XO) system were used to generate active oxygen species. The effects of transfection with the hSOD gene on active oxygen-induced cytotoxicity were assessed by comparing the number of surviving cells and the level of lipid peroxidation in host and transformants after exposure to X/XO system. Results. The cellular SOD activity in RSV-SOD cells transfected with pRc/RSV-SOD was significantly increased in comparison with host or RSV cells transfected with the pRc/RSV plasmid containing no hSOD gene as a control. Furthermore, Western blot analysis using an anti-hSOD antibody indicated the production of hSOD in RSV-SOD cells. On the other hand, although the numbers of surviving cells in both host and RSV-SOD cultures after exposure to X/XO system decreased in a time-dependent manner, the decrease in number of surviving RSV-SOD cells was less than that in host cells. In the presence of catalase, the decreases in number of surviving cells in both host and RSV-SOD cultures after exposure to the X/XO system were also less than those in the absence of catalase. However, the decreases in cell survival in RSV-SOD cultures were significantly less than those in host cells in the presence of catalase. Furthermore, the levels of lipid peroxidation in RSV-SOD cells exposed to the X/XO system in the presence or absence of catalase were lower than those in host cells. These results indicated that the increase in cellular SOD activity by transfection with the hSOD gene protects cells from oxidative stress. Conclusions. Human SOD gene therapy may be useful for treatment of diseases in which oxidative tissue damage is produced.  相似文献   
87.
Interaction of the nucleocapsid (NP) and V proteins of human parainfluenza type 2 virus (HPIV-2) was investigated using a transient expression system. When the NP proteins were co-expressed with the V proteins, some of the NP proteins were translocated into the nuclei. These findings suggest that the NP protein interact with the V proteins. We examined the interaction of the NP proteins and the P, V proteins or deletion mutants of V protein using immunofluorescence and co-immunoprecipitation plus Western blotting analyses, and showed that the V proteins of HPIV-2 bind to the NP proteins and that the N-terminal domain of V protein interacts directly with the NP proteins. When the NP proteins were co-expressed with the V proteins or the N-terminal fragments (aa 1–46), the NP proteins were detected diffusely in the nuclei of the transfected cells, and were also detected in cytoplasmic inclusions. The NP and V proteins were co-localized in the nuclei or cytoplasm. Futhermore, the NP proteins were co-precipitated with the P, V, and V(1–164) proteins by a specific antibody. The P proteins interact more closely with the NP proteins than do the V proteins. These findings indicate that the V proteins have the ability to bind the NP proteins. Received: 4 January 1996  相似文献   
88.
Hemangioendothelioma (HE) is an uncommon vascular tumor that is intermediate in histological appearance between a hemangioma and an angiosarcoma. Presently, it is regarded as endothelial tumors of low-grade or intermediate malignancy. It has been reported in the liver, lung, heart, mediastinum, lymph nodes, extremity, and bone. The occurrence in the brain is extremely rare; only 16 cases have so far been reported. We report a 51-year-old woman who presented with transient visual disturbance and weakness of the left upper limb on April 12th 2003. Computed tomography (CT) revealed a high density mass in the right parietal lobe. In magnetic resonance imaging (MRI), the lesion is hyperintense on TIWI, isointense on T2WI, and no enhancement with gadopentetate dimegliumine. Intratumoral hemorrhage was indicated and preoperative diagnosis was cavernous angioma. The tumor was excised completely on April 28th 2003. Pathologically, the tumor cells resembled endothelial cells, positive immunoreactivity for Factor VIII, and grew in small nests or cords. Postoperative MRI showed complete removal of the tumor. There has been no recurrence for 8 months after the surgery, but we have to follow MRI up for a long time. We discussed intracerebral HE clinically and neuroradiologically.  相似文献   
89.
Five classes of serum immunoglobulin levels were investigated in 107 children with malignant or benign tumors. Hyperimmunoglobulinemia D (hyper-IgD) was observed in 31 of 82 children who were in complete remission off chemotherapy with a median follow-up of 4.5 years after cessation of chemotherapy. On the other hand, hyper-IgD was not found among 12 children with malignant or benign tumors treated with chemotherapy and a low incidence of hyper-IgD was observed during chemotherapy (1 of 13 cases). The result indicates that hyper-IgD is not uncommon in children off chemotherapy, suggesting that dysregulation of IgD synthesis persists long after cessation of antineoplastic drugs.  相似文献   
90.
Abstract: A multidrug-resistant murine lymphoid leukemia P388/ADR overexpresses P-glycoprotein (P-gp), an active transporter that pumps cytotoxic drugs out of cells and a product of mdr1 gene. Cytotoxic T lymphocytes (CTL) that showed cytotoxicity against P388/ADR were generated from mixed lymphocyte tumor cell culture. CTL do not kill drug-sensitive parental P388 (P388/parent) that does not express P-gp. Monoclonal antibody against P-gp inhibited cytotoxic activity. Similar results were obtained in another multidrug-resistant cell line P388/VP-16. Cytotoxic activity was mediated by Thyl+ CD4 CD8+ T-cells. When P388/ADR was treated with murine IL-4, expression of P-gp was downregulated. Monoclonal antibody against interleukin-4 (IL-4) abrogated the IL-4-induced suppression of P-gp. Cytolytic activity of CTL against IL-4-treated P388/ADR was dose dependently inhibited. These results suggest that P-gp is immunogenic and can be a target of CTL in this murine leukemia model.  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