全文获取类型
收费全文 | 225篇 |
免费 | 24篇 |
国内免费 | 48篇 |
专业分类
儿科学 | 10篇 |
妇产科学 | 1篇 |
基础医学 | 19篇 |
口腔科学 | 3篇 |
临床医学 | 49篇 |
内科学 | 50篇 |
皮肤病学 | 2篇 |
神经病学 | 22篇 |
特种医学 | 44篇 |
外科学 | 9篇 |
综合类 | 20篇 |
预防医学 | 11篇 |
眼科学 | 2篇 |
药学 | 53篇 |
中国医学 | 1篇 |
肿瘤学 | 1篇 |
出版年
2023年 | 4篇 |
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2016年 | 1篇 |
2015年 | 6篇 |
2014年 | 4篇 |
2013年 | 9篇 |
2012年 | 1篇 |
2011年 | 2篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 2篇 |
2007年 | 32篇 |
2006年 | 5篇 |
2005年 | 8篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 10篇 |
1997年 | 11篇 |
1996年 | 17篇 |
1995年 | 10篇 |
1994年 | 11篇 |
1993年 | 17篇 |
1992年 | 10篇 |
1991年 | 7篇 |
1990年 | 10篇 |
1989年 | 7篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有297条查询结果,搜索用时 93 毫秒
61.
头颈部放疗患者涎液表皮生长因子水平降低的研究 总被引:1,自引:0,他引:1
本文主要目的是测量头颈部放疗者的涎液表皮生长因子(epidermal growth factor,EGF)水平,并评价EGF与放疗性口腔粘膜炎严重程度是否相关。 材料和方法 将13例头颈部放疗患者和18例与之性别、年龄相当的健康人进行配对研究。在放疗前、中、后分别收集全涎液,测定涎液全蛋白(totalprotein,TP)和EGF浓度,并记录口腔粘膜炎严重程度。 结果和讨论 放疗前涎液EGF和标准化EGF水平及TP水平在放疗组和健康组间的差异不明显。 相似文献
62.
从兔股骨头中提取总RNA的方法特点 总被引:2,自引:1,他引:2
目的:建立一种高效、快速的骨组织总RNA提取方法。方法:实验于2005-01/2006-01在昆明医学院实验动物中心和中国科学院昆明动物研究所中科院细胞与分子进化重点实验室完成。取健康新西兰大白兔1只,截取其股骨头,迅速置于液氮罐中保存,于研钵中研磨,使骨组织始终保存于液氮中,继续研磨,如此重复3次,然后利用Trizol使骨细胞结构迅速破坏,将粉末转入离心管,室温静置5min。随后加入氯仿等有机溶剂处理、离心,使RNA与细胞DNA、蛋白质及其他成分分离从而得到总RNA。最后鉴定RNA的质量、纯度及产率,取2μL提取出的RNA在体积分数为0.008的甲醛变性琼脂糖凝胶上进行电泳,主要观察RNA的28S、18S及5S三个条带是否清晰,有无降解和DNA污染。以99μLDEPC水稀释1μLRNA样品,紫外分光光度计测量其吸光度(A)值,A260/A280之比值表示RNA的纯度,同时根据吸光度值计算其质量浓度。结果:①对提取的兔股骨头RNA进行琼脂糖凝胶电泳,可显示清晰的28S、18S两个条带,5S条带亦可见,表明了RNA是完整的。②用紫外分光光度法测定兔股骨头中提取出的RNAA260/A280,结果表明由本法提取的RNA纯度高,无DNA和蛋白质的污染。③经紫外分光光度计吸收定量,每毫克兔股骨头组织能提取1.0~1.2μg的总RNA。结论:本法提取骨组织总RNA方便、快捷,质量高,可用于骨组织的分子生物学研究。 相似文献
63.
64.
65.
Dopamine D1 receptors can be covalently labeled with the photo-affinity ligand (+-)-7-[125I]iodo-8-hydroxy-3-methyl-1-(4-azidophenyl)-2,3,4,5-tetrah yd ro-1H-3-benzazepine ([125I]IMAB) and visualized following sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. In brain membranes, [125I]IMAB labels a polypeptide of apparent Mr approximately equal to 74,000 as the major ligand binding subunit of D1 receptors and two minor polypeptides of Mr approximately equal to 64,000 and 52,000. In contrast, [125I]IMAB labels a single polypeptide of apparent Mr approximately equal to 64,000 in bovine parathyroid glands. In this study, the carbohydrate nature of dopamine D1 receptors from the brain and parathyroid gland were examined using specific exo- and endoglycosidases and lectin affinity chromatography. [125I]IMAB-labeled brain and parathyroid D1 receptors were sensitive to treatment with the exoglycosidases neuraminidase or alpha-mannosidase, suggestive of the existence of terminal sialic acid and oligomannose residues. Photolabeled D1 receptor polypeptides are not however, associated with distinct populations of complex-type or high mannose-containing carbohydrate chains because 1) wheat germ agglutinin and concanavalin A lectin chromatography of solubilized and photolabeled neuronal D1 receptors followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography revealed no differences in the electrophoretic mobility of column pass-through and specifically eluted [125I]IMAB-labeled polypeptides, and 2) [125I]IMAB-labeled D1 receptors specifically bound to and eluted from concanavalin A-Sepharose were neuraminidase sensitive, indicative of the colocalization of oligomannose- and complex-type glycans. Removal of these terminal glycan residues did not affect the binding of [3H]SCH 23390 to dopamine D1 receptors. Complete N-linked deglycosylation of photolabeled D1 receptors from both the brain and parathyroid with peptide N-glycosidase F resulted in the migration of a single major labeled polypeptide of apparent Mr approximately equal to 46,000. These data suggest that, despite differences observed in the electrophoretic mobility and glycosylation patterns of brain and parathyroid D1 receptor polypeptides, the protein backbones of central and peripheral dopamine D1 receptors display similar if not identical molecular weights. 相似文献
66.
Madras BK Pristupa ZB Niznik HB Liang AY Blundell P Gonzalez MD Meltzer PC 《Synapse (New York, N.Y.)》1996,24(4):340-348
In brain, monoamine transporters are principal targets of widely used therapeutic drugs including antidepressants, methylphenidate (Ritalin), and the addictive drug cocaine. Without exception, these transport blocking agents contain an amine nitrogen. A prevalent view and untested premise is that an amine nitrogen is needed to bind to the same counterion on the transporter as does the amine nitrogen of the monoamine neurotransmitter. We report that several compounds without nitrogen (8-oxa-bicyclo-3-aryl-[3.2.1] octanes, or aryloxatropanes) are active at monoamine transporters. One of these, tropoxane (0-914), bound with high affinity to the dopamine (IC50: 3.35 +/- 0.39 nM), serotonin (IC50: 6.52 +/- 2.05 nM), and norepinephrine (IC50: 20.0 +/- 0.3 nM) transporters in monkey brain, the human striatal dopamine transporter (IC50: 5.01 +/- 1.74 nM), and blocked dopamine transport (IC50: 7.2 +/- 3.0 nM) in COS-7 cells transfected with the human dopamine transporter. These unique compounds require a revision of current concepts of the drug binding domains on monoamine transporters, open avenues for discovery of a new generation of drugs and raise the issue of whether mammalian transporters and receptors may respond to, as yet, undiscovered non-amine bearing neurotransmitters or drugs. 相似文献
67.
Physician support for diabetes patients and clinical outcomes 总被引:1,自引:0,他引:1
Jochen Gensichen Michael Von Korff Carolyn M Rutter Michelle D Seelig Evette J Ludman Elizabeth HB Lin Paul Ciechanowski Bessie A Young Edward H Wagner Wayne J Katon 《BMC public health》2009,9(1):367
Background
Physician practical support (e.g. setting goals, pro-active follow-up) and communicative support (e.g., empathic listening, eliciting preferences) have been hypothesized to influence diabetes outcomes. 相似文献68.
69.
Ramesh Kumar Kushwaha Suresh Kumar Jain HB Abhinandan Dinesh Baheti 《Indian journal of dermatology》2015,60(2):217-Apr;60(2):217
Primary lymphoepithelioma-like carcinoma of the skin (LE-lCS) is a very rare cutaneous malignancy of uncertain origin. The neoplasm reveals typical morphological similarity to undifferentiated nasopharyngeal carcinoma (lymphoepithelioma). This case report presents a 47-year-old man with a 5 mm erythematous papule on dorsal nose of six months duration. The patient underwent complete surgical excision and is disease free 7 months later. 相似文献
70.