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   336篇
  免费   28篇
  国内免费   8篇
儿科学   5篇
基础医学   45篇
临床医学   23篇
内科学   36篇
皮肤病学   8篇
神经病学   64篇
特种医学   5篇
外科学   7篇
综合类   36篇
预防医学   65篇
眼科学   1篇
药学   50篇
中国医学   18篇
肿瘤学   9篇
  2023年   2篇
  2022年   6篇
  2021年   15篇
  2020年   27篇
  2019年   9篇
  2018年   7篇
  2017年   14篇
  2016年   13篇
  2015年   15篇
  2014年   15篇
  2013年   38篇
  2012年   12篇
  2011年   14篇
  2010年   11篇
  2009年   12篇
  2008年   21篇
  2007年   26篇
  2006年   15篇
  2005年   14篇
  2004年   12篇
  2003年   12篇
  2002年   14篇
  2001年   3篇
  2000年   2篇
  1999年   5篇
  1998年   2篇
  1997年   3篇
  1996年   7篇
  1995年   3篇
  1994年   3篇
  1993年   3篇
  1992年   4篇
  1991年   2篇
  1990年   2篇
  1989年   2篇
  1988年   2篇
  1986年   2篇
  1985年   3篇
排序方式: 共有372条查询结果,搜索用时 15 毫秒
61.
62.
63.
目的探讨毒蕈中毒患儿进行血浆置换的效果。方法4例患儿(男3例,女1例),年龄分别为2、6、6、8岁,食用野生蘑菇0.5—1h后出现恶心、呕吐、腹痛、腹泻等急性胃肠道症状。经常规治疗症状无明显缓解,且出现肝及心肌损害。(发病后2-3d)给予血浆置换及对症、支持治疗。密切观察病情。结果入住儿童重症监护中心2周后患儿病情均好转出院。结论及时进行血浆置换能提高毒蕈中毒的救治率。  相似文献   
64.
Malacostracan crustaceans and dicondylic insects possess large second-order olfactory neuropils called, respectively, hemiellipsoid bodies and mushroom bodies. Because these centers look very different in the two groups of arthropods, it has been debated whether these second-order sensory neuropils are homologous or whether they have evolved independently. Here we describe the results of neuroanatomical observations and experiments that resolve the neuronal organization of the hemiellipsoid body in the terrestrial Caribbean hermit crab, Coenobita clypeatus, and compare this organization with the mushroom body of an insect, the cockroach Periplaneta americana. Comparisons of the morphology, ultrastructure, and immunoreactivity of the hemiellipsoid body of C. clypeatus and the mushroom body of the cockroach P. americana reveal in both a layered motif provided by rectilinear arrangements of extrinsic and intrinsic neurons as well as a microglomerular organization. Furthermore, antibodies raised against DC0, the major catalytic subunit of protein kinase A, specifically label both the crustacean hemiellipsoid bodies and insect mushroom bodies. In crustaceans lacking eyestalks, where the entire brain is contained within the head, this antibody selectively labels hemiellipsoid bodies, the superior part of which approximates a mushroom body's calyx in having large numbers of microglomeruli. We propose that these multiple correspondences indicate homology of the crustacean hemiellipsoid body and insect mushroom body and discuss the implications of this with respect to the phylogenetic history of arthropods. We conclude that crustaceans, insects, and other groups of arthropods share an ancestral neuronal ground pattern that is specific to their second-order olfactory centers.  相似文献   
65.
66.
Objective: In this study, we aimed to harness some solvent extracts of one wild mushroom Hexagonia glabra and test their anti-cancer activity against cervical human cell lines, namelyHeLa, SiHa, and CaSki. Methods: It includes cell morphological study by microscope, nuclear morphology by DAPI staining under fluorescence microscopy, apoptosis assay by fluorescence technique, anti-proliferation by MTT assay and expression of apoptotic and anti-apoptotic genes by Western blotting and cell cycle analysis was done. Results: The selected cervical cancer cells were treated separately with 150 µg/mL of three extracts, namely of ethanolic (EE), ethyl acetate (EAE), and water extract (WE) and exhibited features like round, shrink and dead. All extracts caused apoptosis in cell lines and EE had the highest effect in this regard. The percentages of apoptotic cells in HeLa, SiHa and CaSki, at the same concentration of EE were 79.23, 75.42, and 76.36% respectively. Cytotoxicity assay showed that all three extracts (50 – 250 μg/mL) were potent for inhibition of cell growth of three cell lines and again EE had the highest effect. The percentages of cell growth inhibition in HeLa, SiHa, and CaSki cells treated with EE at 24 h at 50 µg/mL were 45.79±4.11, 41.66±4.03, and 36.72±2.67, while they were 74.23±7.45, 62.31±5.97, and 54.23±5.04 at 150 µg/mL concentration. At 250 µg/mL concentration, the percentages of cell growth inhibition were 94.25 ±8.11, 90.02 ±8.67, and 85.43±6.21, respectively. The expression of apoptotic gene (Caspase 3, 9) and tumor guard gene (p53), as their proteins in Western blotting increased . However, anti-apoptotic BcL2 gene of all cell lines was decreased following treatment with extracts. In addition, the cell cycle analysis (CaSki cell) showed that treatment (EE) arrested at G2/M check point cell cycle. Conclusion: All extracts of this mushroom were active in arresting growth of three cell lines and EE had the highest effect, indicating that this mushroom can be a valuable source of anticancer agents.  相似文献   
67.
68.
The aim of the present study was to evaluate in vitro the beneficial potential of crude polysaccharides from S. crispa (CPS) in one of the most common cancer types—colon cancer. The determination of the chemical composition of CPS has revealed that it contains mostly carbohydrates, while proteins or phenolics are present only in trace amounts. 1H NMR and GC–MS methods were used for the structural analysis of CPS. Biological activity including anticancer, anti-inflammatory and antioxidant properties of CPS was investigated. CPS was found to be non-toxic to normal human colon epithelial CCD841 CoN cells. Simultaneously, they destroyed membrane integrity as well as inhibited the proliferation of human colon cancer cell lines: Caco-2, LS180 and HT-29. Antioxidant activity was determined by various methods and revealed the moderate potential of CPS. The enzymatic assays revealed no influence of CPS on xanthine oxidase and the inhibition of catalase activity. Moreover, pro-inflammatory enzymes such as cyclooxygenase-2 or lipooxygenase were inhibited by CPS. Therefore, it may be suggested that S. crispa is a valuable part of the regular human diet, which may contribute to a reduction in the risk of colon cancer, and possess promising activities encouraging further studies regarding its potential use as chemopreventive and therapeutic agent in more invasive stages of this type of cancer.  相似文献   
69.
通过对36处平菇生产现场、377名栽培人员的劳动卫生学调查、临床检查、免疫学研究、霉菌培养和动物实验证实,以棉籽皮为培养基栽培平菇,其职业性呼吸道疾病的病原是平菇本身释放的担孢子,而与普通高温放线菌、小多芽胞霉菌等嗜热性放线菌的孢子无关。本文并探讨了平菇栽培人员呼吸道疾病的发病规律、临床特征,建议将临床诊断分为蘑菇孢子过敏性支气管炎和肺泡炎(蘑菇工肺)。  相似文献   
70.
大鼠对富硒平菇硒的生物利用率   总被引:1,自引:0,他引:1  
孙群  祝寿嵩 《营养学报》1993,15(4):426-431
本实验用低硒大鼠对人工栽培富硒平菇作了硒生物利用率观察。大鼠按体重随机分为9组,其中1组为低硒对照组,2~5组补充Na_2SeO_3,饲料内硒含量分别为:0.51、0.75、1.91、3.18ppm;6~9组补充富硒平菇,硒为0.45、0.72、1.59、3.41ppm。3周后处死大鼠,采血、肝、测定硒含量,并测定红细胞GSH-Px酶活性。结果表明:血、肝硒值及红细胞GSH-Px酶活性均随补硒浓度的增加而增加,以亚硒酸钠为基准,富硒平菇硒生物利用率,按血硒指标为66.66%;按肝硒指标为125%;按红细胞GSH-Px酶活性指标为123.42%,说明人工栽培富硒平菇可作为极好的食物硒来源。  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