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   575篇
  免费   49篇
  国内免费   8篇
耳鼻咽喉   1篇
儿科学   74篇
妇产科学   11篇
基础医学   52篇
口腔科学   38篇
临床医学   66篇
内科学   147篇
皮肤病学   10篇
神经病学   32篇
特种医学   73篇
外科学   42篇
综合类   9篇
一般理论   1篇
预防医学   28篇
眼科学   4篇
药学   30篇
肿瘤学   14篇
  2021年   5篇
  2020年   2篇
  2019年   7篇
  2018年   5篇
  2017年   5篇
  2016年   4篇
  2015年   12篇
  2014年   10篇
  2013年   21篇
  2012年   11篇
  2011年   17篇
  2010年   21篇
  2009年   18篇
  2008年   15篇
  2007年   21篇
  2006年   9篇
  2005年   11篇
  2004年   11篇
  2003年   16篇
  2002年   13篇
  2001年   12篇
  2000年   8篇
  1999年   10篇
  1998年   22篇
  1997年   38篇
  1996年   34篇
  1995年   21篇
  1994年   24篇
  1993年   22篇
  1992年   7篇
  1991年   18篇
  1990年   16篇
  1989年   17篇
  1988年   19篇
  1987年   14篇
  1986年   17篇
  1985年   12篇
  1984年   7篇
  1983年   16篇
  1982年   18篇
  1981年   15篇
  1980年   6篇
  1979年   3篇
  1978年   2篇
  1977年   2篇
  1976年   3篇
  1975年   2篇
  1972年   2篇
  1970年   2篇
  1968年   4篇
排序方式: 共有632条查询结果,搜索用时 15 毫秒
131.
132.
133.
This study was performed to determine whether peritoneal T cells are suppressed in the CD4+ or CD8+ T cell subpopulation and whether they are Th1 or Th2 predominant in women with endometriosis. Immune cells in the peritoneal fluid (PF) were obtained from women undergoing laparoscopy for endometriosis or tubal ligation. Three-colour flow cytometry was utilized for immunophenotyping of peritoneal fluid mononuclear cells (PFMC). Concentrations of interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma) produced by PFMC with and without mitogen stimulation and concentrations of IL-10 and IL-12 were measured in PF. The peritoneal T lymphocytes were predominantly of the Th1 type that produced much more IFN-gamma but less IL-4 or IL-5 in women with or without endometriosis. The decrease in peritoneal lymphocytes was significant in the HLA-DR+ CD4+ CD3+ subpopulation and the concentrations of peritoneal IL-10 and IL-12 were significantly elevated in women with early stage endometriosis. There was impaired IL- 5 production by PFMC after phytohaemagglutinin stimulation in women with advanced stage endometriosis. We concluded that the activated peritoneal CD4+ Th1 cells from the women with endometriosis were decreased in number. The suppression of these T cells may be due to the elevation of IL-10 and IL-12 in the peritoneal fluid.   相似文献   
134.
本文观察了莨菪类药物(东茛菪碱、樟柳碱、山茛菪碱)对大鼠三种实验性胃溃疡的影响,并对其作用机制进行了初步的探讨。结果表明:莨菪类药物有对抗大鼠应激性胃溃疡、药物性胃溃疡及慢性胃溃疡的作用,且有量效依赖关系;对胃液和血液等各项生化指标分析表明,这类药物有抑制胃酸分泌、降低胃蛋白酶活性、增强胃粘液屏障,提高血清胃泌素浓度的作用。提示这些结果可能与其抗溃疡效应有关。  相似文献   
135.
Abstract: The stories in this Roundtable Discussion are related by two women whose babies were born recently in Canadian hospitals. Each woman had undergone a cesarean delivery for her first child, and whereas Sophia delivered her second baby by vaginal birth after a cesarean (VBAC), Marie was unable to find a practitioner or hospital that would allow her to have a VBAC for her second birth. The women describe how they feel about their choices and experiences. Their two accounts and the issues that they raise are discussed in commentaries by a family physician, midwife, doula, and obstetrician. (BIRTH 37:3 September 2010)  相似文献   
136.
Our aim in this Gadamerian hermeneutic study was to understand maternal breastfeeding confidence and its meaning through listening to women's voices describing their experiences within the context of the United States. We asked 13 women, aged 23 to 42 years, who had breastfed a child within the last 2 years to tell us their breastfeeding stories. Women experienced maternal breastfeeding confidence as a dynamic interaction between their expectations, their infants breastfeeding behavior, and sources of support. They described experiences that enhanced or diminished their confidence. Health professionals can use these findings to plan approaches that promote and support maternal breastfeeding confidence.  相似文献   
137.
The purpose of this longitudinal qualitative study was (1) to extend the work of Belenky, Clinchy, Goldberger, and Tarule by interviewing female university nursing students to determine their "way of knowing" according to the Women's Ways of Knowing (WWK) schema and (2) to determine what relationship this way of knowing might have with critical thinking when accumulating a specific body of knowledge such as nursing. Interviews were conducted with 21 sophomore nursing students. Fourteen were reinterviewed their junior year, and 10 were interviewed or participated in a focus group their senior year. The procedural knowledge categories of separate and connected knowing became the focus of data analysis through the constant comparative method. Procedures for connected knowing were illuminated. Connected knowing was found to be congruent with nursing and the ways these women wanted to be as nurses. Separate knowing was found to be incongruent with nursing except for critical thinking purposes. Contrary to the notion that critical thinking is principled rather than procedural, procedural knowing, according to WWK, became the principle on which these women based their nursing actions, moving them to constructed knowers and caring, critical thinkers as they experienced nursing education.  相似文献   
138.
目的:在肝细胞癌动物模型上观察聚丙交酯复合乙交酯(PLcG)微球经肝动脉化疗栓塞术(TACE)治疗肝癌的疗效。方法:在雄性ACI大鼠(15例)肝包膜下植入Morris Hepatoma 3924A肝癌小瘤块(1mm3),移植术中13天时行磁共振检查,再经正中腹切开术和经胃十二指肠动脉逆行插管进行以下介入治疗:治疗组A(40mg PLcG 0.05mg丝裂霉素,4例),对照组B(0.05mg丝裂霉素+0.04mg碘化油+肝动脉结扎,4例)和对照组C(1.5ml生理盐水,7例),插管术后13天再次行磁共振术观察肝肿瘤体积变化。结果:在C组,肿瘤体积在实验期间增长27.12倍,在B组,肿瘤体积增长3.76倍,而在A组,肿瘤体积仅增长2.87倍。A组与C组肿瘤体积增长率在t检验时均有显著性差异(P<0.05),结论:在动物实验中将PLcG微球运用于TACE可明显抑制肝肿瘤生长。  相似文献   
139.

Background and purpose:

Compound LASSBio-881 is an orally effective antinociceptive that binds to cannabinoid receptors and is active mainly on the neurogenic component of pain models. We investigated whether transient receptor potential vanilloid subfamily type 1 (TRPV1) channels are involved in the effects of LASSBio-881.

Experimental approach:

Modulation of capsaicin (CAP)- and low pH-induced currents was evaluated in TRPV1-expressing Xenopus oocytes. In vivo effects were evaluated in CAP-induced acute and inflammatory changes in nociception, as well as in partial sciatic ligation-induced thermal hypernociception.

Key results:

LASSBio-881 inhibited TRPV1 currents elicited by CAP with an IC50 of 14 µM, and inhibited proton-gated currents by 70% at 20 µM. Functional interaction with CAP was surmountable. Locally applied LASSBio-881 decreased time spent in CAP-elicited nocifensive behaviour by 30%, and given orally it reduced measures of CAP- or carrageenan-evoked thermal hypernociception by 60 and 40% respectively. In addition, LASSBio-881 decreased the paw withdrawal responses to thermal stimuli of animals with sciatic neuropathy 7–11 days after nerve ligation, at a dose of 300 µmol·kg−1·day−1 p.o. At this dose, hyperthermia was not observed within 4 h following oral administration.

Conclusions and implications:

LASSBio-881 is a TRPV1 antagonist that apparently competes with CAP. Accordingly, LASSBio-881 inhibited nociception in models of acute, inflammatory and neuropathic pain presumed to involve TRPV1 signalling. These in vivo actions were not hindered by hyperthermia, a common side effect of other TRPV1 antagonists. We propose that the antinociceptive properties of LASSBio-881 are due to TRPV1 antagonism, although other molecular interactions may contribute to the effects of this multi-target drug candidate.  相似文献   
140.
Banded bone marrow chromosome analyses have been done on 83 unselected patients with acute lymphoblastic leukemia (ALL). Seven patients, all with non-T, non-B ALL, had a translocation involving the long arms of chromosomes 4 and 11. Five of these patients, 4 children and 1 adult, were first studied at diagnosis, and the t(4;11) (q21;q23) was the only karyotypic abnormality. All 5 presented with a marked leukocytosis (greater than 150 X 10(9)/liter). Four of these 5 patients achieved a complete remission following the same intensive treatment regimen; however, remission duration and survival were very short (medians 2.5 and 8 mo, respectively). The fifth patient is currently receiving induction chemotherapy. The remaining 2 patients, both adults, were studied in relapse only, and had other karyotypic abnormalities in addition to the t(4;11). One of these relapse patients was a female whose clinical presentation and course were similar to those above. The last patient was a male who presented with a leukocyte count of 7 X 10(9)/liter and maintained an initial complete remission for 37 mo. Our data suggest that patients who have a t(4;11) (q21;q23) at the time of diagnosis of ALL have a poor prognosis with conventional therapy and require a new therapeutic approach.  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