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   322篇
  免费   16篇
  国内免费   13篇
儿科学   34篇
妇产科学   3篇
基础医学   40篇
口腔科学   12篇
临床医学   32篇
内科学   53篇
皮肤病学   7篇
神经病学   5篇
特种医学   93篇
外科学   9篇
综合类   4篇
预防医学   9篇
眼科学   10篇
药学   20篇
肿瘤学   20篇
  2022年   1篇
  2021年   3篇
  2020年   1篇
  2019年   2篇
  2018年   3篇
  2017年   3篇
  2016年   3篇
  2015年   12篇
  2014年   5篇
  2013年   9篇
  2012年   10篇
  2011年   1篇
  2010年   14篇
  2009年   10篇
  2008年   6篇
  2007年   12篇
  2006年   4篇
  2005年   4篇
  2004年   3篇
  2003年   4篇
  2002年   6篇
  2001年   2篇
  2000年   18篇
  1999年   3篇
  1998年   25篇
  1997年   39篇
  1996年   27篇
  1995年   18篇
  1994年   14篇
  1993年   6篇
  1992年   4篇
  1991年   1篇
  1990年   4篇
  1989年   11篇
  1988年   10篇
  1987年   1篇
  1986年   5篇
  1985年   5篇
  1984年   2篇
  1983年   10篇
  1982年   5篇
  1981年   3篇
  1980年   5篇
  1978年   2篇
  1977年   7篇
  1976年   4篇
  1975年   3篇
  1973年   1篇
排序方式: 共有351条查询结果,搜索用时 588 毫秒
91.
结肠黑变病的研究现状及进展   总被引:5,自引:0,他引:5  
随着便秘的发病率增加和结肠镜检查率提高,结肠黑变病的检出率明显升高,其具体的病因及发病机制不清,多与服用泻药和便秘有关.随着分子生物学技术的广泛应用及动物实验研究的深入,会逐步认识结肠黑变这种现象.目前研究的重点多集中于结肠黑变与结肠上皮细胞增殖与凋亡;泻剂滥用造成的结肠运动功能的改变的原理;该病与结肠肿瘤、息肉、息肉病等细胞增殖性疾病相关性.我们综述近年的相关文献,从流行病学、发病相关因素、病理形态学改变及治疗和预后等方面加以分析和总结,以期对该病以及相关疾病加深认识.  相似文献   
92.
Cyclin D1 promotes cell cycle progression during G1 phase, a key event in G1‐S transition. The protein is encoded by gene CCND1, located in chromosomal band 11q13. Cyclin D1 plays key roles in cell biology, including cell proliferation and growth regulation, mitochondrial activity modulation, DNA repair, and cell migration control. CCND1 gene and its protein cyclin D1 are frequently altered by different molecular mechanisms, including amplification, chromosomal translocations, mutations, and activation of the pathways involved in cyclin D1 expression, alterations which appear to be essential in the development of human cancers, including oral carcinoma. This is the first published review of the specific features of cyclin D1 overexpression in oral oncogenesis. Starting with the physiological regulation of cyclin D1, there is an evaluation of its functions, overexpression mechanisms, and the implications of the oncogenic activation of CCND1/cyclin D1 in oral squamous cell carcinoma . The potential diagnostic and prognostic value of cyclin D1 is reviewed. The influence of CCND1/cyclin D1 on tumor size and clinical stage is reported, and an update is provided on the utilization of cyclin D1 as therapeutic target and on the combination of cyclin D1 inhibitors with cytotoxic agents. Future research lines in this field are also proposed.  相似文献   
93.
94.
100 classic papers of interventional radiology: A citation analysis   总被引:1,自引:0,他引:1  
AIM: To define the 100 citation classic papers of interventional radiology.METHODS: Using the database of Journal Citation Reports the 40 highest impact factor radiology journals were chosen. From these journals the 100 most cited interventional radiology papers were chosen and analysed.RESULTS: The top paper received 2497 citations and the 100 th paper 200 citations. The average number of citations was 320. Dates of publication ranged from 1953- 2005. Most papers originated in the United States(n = 67) followed by Italy(n = 20) and France(n = 10). Harvard University(n = 18) and Osped Civile(n = 11) were the most prolific institutions. Ten journals produced all of the top 100 papers with "Radiology" and "AJR" making up the majority. SN Goldberg and T Livraghi were the most prolific authors. Nearly two thirds of the papers(n = 61) were published after 1990.CONCLUSION: This analysis identifies many of the landmark interventional radiology papers and provides a fascinating insight into the changing discourse within the field. It also identifies topics, authors and institutions which have impacted greatly on the specialty.  相似文献   
95.
96.
The polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes (POEMS) syndrome is a rare multisystem disorder of obscure pathogenesis associated with osteosclerotic myeloma. Circulating levels of proinflammatory cytokines (tumor necrosis factor-alpha (TNF-alpha) interleukin-1 beta [IL-1 beta], IL-2, IL-6, and interferon-gamma [IFN- gamma]), anti-inflammatory cytokines (transforming growth factor beta 1 [TGF beta 1], IL-4, IL-10, and IL-13), the cytokine carrier protein alpha 2 macroglobulin, IL-1 receptor antagonist (IL-1ra), soluble TNF receptors (sTNFr) p55 and p75, and soluble IL-6 receptor (sIL-6r) were determined in 15 patients with POEMS syndrome and 15 with multiple myeloma. Patients with POEMS syndrome had higher serum levels of IL-1 beta, TNF-alpha, and IL-6 and lower serum levels of TGF beta 1 than did patients with multiple myeloma. Serum levels of IL-2, IL-4, IL-10, IL- 13, IFN-gamma, alpha 2 macroglobulin, and sIL-6r were similar in both groups. IL-1ra and sTNFrs were increased in POEMS syndrome, but out of proportion to the increase of IL-1 beta and TNF-alpha. Serial evaluations in 1 patient showed that proinflammatory cytokine serum levels paralleled disease activity assessed by platelet count and neurologic involvement. Our results suggest that the manifestations of POEMS syndrome might be regarded as the result of a marked activation of the proinflammatory cytokine network (IL-1 beta, IL-6, and TNF- alpha) associated with a weak or even decreased (TGF beta 1) antagonistic reaction insufficient to counteract the noxious effects of cytokines.  相似文献   
97.
Nelson  EL; Li  X; Hsu  FJ; Kwak  LW; Levy  R; Clayberger  C; Krensky  AM 《Blood》1996,88(2):580-589
Patients with non-Hodgkin's B-cell lymphoma who received an antitumor vaccine of idiotypic ig protein showed humoral and proliferative immune responses. Because immunity to some antigens, including tumor antigens and human pathogenic viruses, may be better correlated with the cytolytic cellular immune response, we evaluated 16 non-Hodgkin's lymphoma patients immunized with autologous idiotypic ig molecules for changes in tumor-specific cytotoxic T-lymphocyte precursor (CTLp) frequency using limiting dilution analysis. Eleven patients had a significant increase in tumor-specific CTLp. Eight of these 11 patients remain without evidence of disease or with stable minimal disease. In contrast, all five patients who did not have a significant change in tumor-specific CTLp have developed progressive disease. Patient vaccination with tumor associated protein antigens can increase tumor- specific CTLp frequencies. The correlation of increased tumor specific CTLp with freedom from progression is significant at P = .002. This study indicates that measurement of CTLp frequencies are relevant to the clinical evaluation of human tumor vaccines and suggests that cell- mediated cytolytic immune responses may be an important determinant of vaccine efficacy.  相似文献   
98.
背景和目的:乳酸水平增高与患者的致病率和病死率显著相关.该研究探讨了在危重患者的早期治疗中,监测乳酸水平是否可以改善患者的预后及其效果.方法:将入住ICU时血乳酸水平≥3.0 mmol/L(3.0 mEq/L)的患者随机分为2组,乳酸组以乳酸水平指导治疗,使患者在最初8h内乳酸水平每2h 下降20%以上;对照组仅有基线乳酸水平,不进行乳酸水平监测.  相似文献   
99.
Swift PGF, Skinner TC, de Beaufort CE, Cameron FJ, Åman J, Aanstoot H‐J, Castaño L, Chiarelli F, Daneman D, Danne T, Dorchy H, Hoey H, Kaprio EA, Kaufman F, Kocova M, Mortensen HB, Njølstad PR, Phillip M, Robertson KJ, Schoenle EJ, Urakami T, Vanelli M, Ackermann RW, Skovlund SE for the Hvidoere Study Group on Childhood Diabetes. Target setting in intensive insulin management is associated with metabolic control: the Hvidoere Childhood Diabetes Study Group Centre Differences Study 2005. Objective: To evaluate glycaemic targets set by diabetes teams, their perception by adolescents and parents, and their influence on metabolic control. Methods: Clinical data and questionnaires were completed by adolescents, parents/carers and diabetes teams in 21 international centres. HbA1c was measured centrally. Results: A total of 2062 adolescents completed questionnaires (age 14.4 ± 2.3 yr; diabetes duration 6.1 ± 3.5 yr). Mean HbA 1c = 8.2 ± 1.4% with significant differences between centres (F = 12.3; p < 0.001) range from 7.4 to 9.1%. There was a significant correlation between parent (r = 0.20) and adolescent (r = 0.21) reports of their perceived ideal HbA1c and their actual HbA1c result (p < 0.001), and a stronger association between parents' (r = 0.39) and adolescents' (r = 0.4) reports of the HbA1c they would be happy with and their actual HbA1c result. There were significant differences between centres on parent and adolescent reports of ideal and happy with HbA1c (8.1 < F > 17.4;p < 0.001). A lower target HbA1c and greater consistency between members of teams within centres were associated with lower centre HbA1c (F = 16.0; df = 15; p < 0.001). Conclusions: Clear and consistent setting of glycaemic targets by diabetes teams is strongly associated with HbA1c outcome in adolescents. Target setting appears to play a significant role in explaining the differences in metabolic outcomes between centres.  相似文献   
100.
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