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   1368篇
  免费   137篇
  国内免费   5篇
耳鼻咽喉   25篇
儿科学   75篇
妇产科学   23篇
基础医学   204篇
口腔科学   58篇
临床医学   118篇
内科学   278篇
皮肤病学   39篇
神经病学   34篇
特种医学   148篇
外科学   128篇
综合类   142篇
预防医学   65篇
眼科学   5篇
药学   80篇
肿瘤学   88篇
  2021年   38篇
  2019年   14篇
  2018年   18篇
  2017年   19篇
  2016年   14篇
  2015年   18篇
  2014年   17篇
  2013年   32篇
  2012年   36篇
  2011年   28篇
  2010年   36篇
  2009年   35篇
  2008年   44篇
  2007年   47篇
  2006年   55篇
  2005年   41篇
  2004年   52篇
  2003年   34篇
  2002年   43篇
  2001年   35篇
  2000年   35篇
  1999年   37篇
  1998年   37篇
  1997年   40篇
  1996年   34篇
  1995年   30篇
  1994年   38篇
  1993年   17篇
  1992年   36篇
  1991年   21篇
  1990年   27篇
  1989年   34篇
  1988年   40篇
  1987年   38篇
  1986年   36篇
  1985年   30篇
  1984年   34篇
  1983年   26篇
  1982年   14篇
  1981年   20篇
  1980年   22篇
  1979年   29篇
  1978年   16篇
  1977年   20篇
  1976年   12篇
  1975年   15篇
  1974年   15篇
  1973年   12篇
  1972年   12篇
  1971年   18篇
排序方式: 共有1510条查询结果,搜索用时 0 毫秒
1.
Interferon-alpha (IFN-alpha) has proved effective in the treatment of hemangiomas, hemangioblastomas, and Kaposi's sarcoma. To investigate the ability of IFNs to inhibit angiosarcoma, we used two transformed murine endothelial cell lines that form angiosarcomas in vivo. SVR and MS1-VEGF cell lines express oncogenic H-ras or vascular endothelial growth factor (VEGF), respectively. IFN-alpha1,8, which is active against murine and human cells, inhibited SVR and MS1-VEGF proliferation in vitro by 40% at 10(3) U/mL (p = 0.028). In vivo, IFN-alpha1,8 inhibited SVR tumor volume by 71% (p = 0.047) and MS1-VEGF volume by 79% (p = 0.003). Tumor-induced angiogenesis was decreased in SVR tumors by 52% (p = 0.005) and in MS1-VEGF tumors by 58% (p = 0.001). Sera from IFN-alpha1,8-treated mice bearing either SVR or MS1-VEGF tumors demonstrated a 5-fold increase in IP-10/CXCL10 (p = 0.001), an IFN-induced antiangiogenic protein. Both recombinant IP-10 and IFN-alpha1,8 inhibited human umbilical vein endothelial cell (HUVEC) vessel formation in the fibrin gel assay, a three-dimensional culture model of angiogenesis, by 56% at 25 ng/mL and 50% at 1.2 ng/mL, respectively (p < 0.001). An IP-10 blocking antibody restored vessel formation to 80% of untreated controls (p = 0.001). Given the magnitude of the in vivo response, these data suggested that the antitumor effects of IFN-alpha1,8 were likely mediated through angiogenesis inhibition rather than solely by direct inhibition of tumor cell proliferation.  相似文献   
2.
3.
4.
5.
6.
In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment.  相似文献   
7.
Salivary disease in childhood is uncommon. Clinical features are much the same as in adult disease, however, congenital, inflammation, and functional disease is more common. Management is governed by the same general principles in all age groups. Congenital abnormalities are rare. Inflammation, either bacterial or viral, is the most common disease. Chronic sialadenitis usually resolves at puberty. Neoplasia is rare, and the majority of tumors are benign and occur in the parotid gland. Malignancy is suggested by rapid growth, pain, skin fixation, and lymphadenopathy. Surgical treatment of sialorrhea should only be considered after careful assessment. Relocation of the submandibular ducts is the treatment of choice.  相似文献   
8.
The cases of 46 children who had been abused sexually an average of 2.6 years previously, were reviewed and the non-offending parents were interviewed with emphasis on how they viewed the professional persons who had seen their children, and their opinions of the legal processes that were instituted. The parents found most professional groups helpful, with officers from the Department of Youth and Community Services being seen as the least helpful. Twenty-one of the cases went to court; in 12 cases this resulted in a conviction, and prison sentences were imposed on six of the offenders. Children found the court experience distressing and most parents expressed dissatisfaction with the outcome of the court hearing. Children were more likely to be required to give evidence in court if the offender had legal representation. Persisting behavioural problems and poor school performance were more likely to occur in those cases in which there had been court hearings. A review of Police Department records of children who had attended the hospital for the management of sexual assault, showed that 10 of the 107 children who are now aged over 14 years, have themselves been convicted of violent crimes since their episode of sexual assault. Long-term intervention is required to help many of these children, some legal reforms are necessary to reduce the stress that they experience when there is a court hearing, and all the professional groups that are likely to become involved with the problem of the sexual abuse of children need to be better informed about its seriousness and consequences.  相似文献   
9.
A study of 17 patients with autoimmune axonal or demyelinating peripheral neuropathy in combination with M-component is described. The M-component was associated with MGUS (monoclonal gammopathy of undetermined significance) in 12 patients, CLL in one patient, WaldenstrÖm's disease in one patient, and myeloma in three patients. Immunohistological examination with direct and indirect fluorescence showed binding of antibodies to nerve structures of the same class and light chain as seen in the M-component. In five cases of IgM M-component, the demyelinating neuropathy was caused by binding of the IgM M-protein and complement C3b to myelin-associated glycoproteins (MAG). In 12 cases with axonal neuropathy, binding of IgG to the connective tissue of the peri- and endoneurium was found in 50% of cases, IgM in five cases, and IgD in one case. None of the patients had central nervous system (CNS) symptoms. The clinical and therapeutic difficulties are discussed; only two patients with an acute course responded to immunosuppression. A marked co-expression of other autoimmune phenomena is interpreted in the light of cross-reactions between the autoantibody and similar tissue autoantigens.  相似文献   
10.
Teaching children about skin cancer prevention: why wait for adolescence?   总被引:1,自引:0,他引:1  
Abstract: The baseline knowledge about skin cancer prevention of 983 children aged 8 to 12 years was assessed by a pretest questionnaire. After the pretest, half were given a formal presentation about skin cancer prevention. The other half participated in an informal, question–and–answer session, which covered all material from the formal presentation. Two weeks later, all students completed an identical post–test. The students had a high baseline level of knowledge about skin cancer prevention. Knowledge increased for most items in the post–test questionnaire. In all age groups there was no difference in results between the formal and interactive teaching sessions, except among eight–year–olds, for whom the formal presentation was more effective. As much solar skin damage occurs before adolescence, the younger age group is the important target for skin cancer prevention programs. (Aust N Z J Public Health 1997; 21: 602–5)  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