全文获取类型
收费全文 | 43539篇 |
免费 | 4308篇 |
国内免费 | 3030篇 |
专业分类
耳鼻咽喉 | 326篇 |
儿科学 | 534篇 |
妇产科学 | 363篇 |
基础医学 | 3948篇 |
口腔科学 | 750篇 |
临床医学 | 5871篇 |
内科学 | 5282篇 |
皮肤病学 | 466篇 |
神经病学 | 1628篇 |
特种医学 | 1579篇 |
外国民族医学 | 3篇 |
外科学 | 3655篇 |
综合类 | 10604篇 |
现状与发展 | 17篇 |
预防医学 | 3990篇 |
眼科学 | 895篇 |
药学 | 4858篇 |
56篇 | |
中国医学 | 3208篇 |
肿瘤学 | 2844篇 |
出版年
2024年 | 155篇 |
2023年 | 557篇 |
2022年 | 1443篇 |
2021年 | 1936篇 |
2020年 | 1573篇 |
2019年 | 1163篇 |
2018年 | 1200篇 |
2017年 | 1261篇 |
2016年 | 1133篇 |
2015年 | 1762篇 |
2014年 | 2275篇 |
2013年 | 2394篇 |
2012年 | 3530篇 |
2011年 | 3911篇 |
2010年 | 3071篇 |
2009年 | 2589篇 |
2008年 | 2812篇 |
2007年 | 2812篇 |
2006年 | 2626篇 |
2005年 | 2210篇 |
2004年 | 1955篇 |
2003年 | 1864篇 |
2002年 | 1681篇 |
2001年 | 1273篇 |
2000年 | 910篇 |
1999年 | 633篇 |
1998年 | 391篇 |
1997年 | 401篇 |
1996年 | 291篇 |
1995年 | 233篇 |
1994年 | 204篇 |
1993年 | 111篇 |
1992年 | 134篇 |
1991年 | 102篇 |
1990年 | 55篇 |
1989年 | 75篇 |
1988年 | 53篇 |
1987年 | 34篇 |
1986年 | 25篇 |
1985年 | 13篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1981年 | 7篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1969年 | 1篇 |
1928年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
Mast cells in adenoid liver tumors of 32 rats induced with nitrosomorpholine were observed ultrastructurally, and among them, some were studied immunocytochemically via immunogold techniques. Data indicating that mast cells which located in tumor tissues presented positive expression of rat mast cell protein (RMCP) Ⅰ, Indicating origination from the mucosa mast cells, while those in the connective tissues around tumors were largely stained negatively with either RMCP Ⅰor RMCP Ⅰ antisera, with the exception of only a few cells showing positive RMCP Ⅰ staining. Ultrastructural observation showed that mast cells in tumon contacted closely with the tumor cells. Membranes of the intracytoplasmic granules in these mast cells were fusing together. The content inside the granules were discharged and spread along the intercellular space between the tumor cells. There was not any lesion observed uitrasructrually in the tumor cells contacting with the mast cells. The significance of mucosa mast cells in adenoi 相似文献
112.
本研究采用中国修订的韦氏儿童智力量表(WISC-CR)、韦氏儿童记忆量表(WMSC-CR),艾森克个性问卷(EPQ)和Achenbach儿童行为量表(ACBC),对39例(未用药组22例,用药组17例)7~14岁Tourette综合征(TS)患儿进行测试,同时采用放射免疫方法测定其血浆催乳素(PRL)含量,并与18例正常对照组比较。结果表明:TS患儿智力测验和记忆测验中的背数、译码和视觉再生分测验量表分低于对照组。其个性测验中的神经质(N)和精神质(P)量表T分高于对照组,掩饰性(L)量表T分低于对照组。其ACBC总分高于对照组。用药组的记忆商(MQ)、理解记忆和累加分测验量表分低于未用药组,TS患儿的血浆催乳素含量高于对照组。相关分析表明血浆催乳素含量与ACBC总分和精神抑制药物如氟哌啶醇和泰必利等因素有关。我们的初步研究提示TS患儿存在不同程度的神经心理缺陷,催乳素可能参与TS发病过程,氟哌啶醇和泰必利等精神抑制药物可能对TS患儿的记忆功能有影响以及可以导致血浆催乳素分泌增加,为TS的防治干预提供了一定的理论依据。 相似文献
113.
慢性粒细胞白血病100例骨髓组织病理学Hannover分类法意义探讨 总被引:2,自引:0,他引:2
本文对100例慢性粒细胞白血病(CML)患者进行组织病理学研究,应用Hannover国际分类法进行分类,观察到骨髓组织病理学中巨核细胞增多者临床症状较重,中位生存时间较短,认为该分类法对临床及预后判断有指导意义,比既往应用的Bartl及Frisch分类法优越。 相似文献
114.
本文利用示差导数光谱法对感冒通片中双氯灭痛和扑尔敏进行定量测定。本法用同一样品液,在同一测定条件下完成,具有操作简便、快速、灵敏度高和重现性好等特点,双氯灭痛和扑尔敏的平均回收率分别为99.5%和97.3%,变异系数分别为0.42%和0.63%. 相似文献
115.
为探讨四君子汤对烧伤早期代谢营养的作用,采用30%Ⅲ度烧伤豚鼠胃造口模型将400g左右豚鼠分别在喂养等量热卡、氮和自由进食两种膳食条件下,将31只豚鼠分为四组,即喂养治疗组(n=7),喂养对照组(n=4),自食治疗组(n=9),自食对照组(n=11)予以观察。结果发现:自由进食时,四君子汤能增加摄食量,减轻伤后体重丢失,改善氮平衡,增加肝、回肠粘膜含氮量,而躯壳重及腓肠肌含氮量增加不明显,但静息代谢率则增加;等量喂养时,四君子汤治疗组体重、躯壳重及腓肠肌含氮量显著低于对照组,而肝、肠粘膜重量及含氮量差异无显著意义。此外,四君子汤还可调整激素和内脏组织含水量。因此,我们认为四君子汤对改善烧伤后代谢营养及脏器功能可能是有益的 相似文献
116.
X M Ruan J H Qiao A Trento L S Czer C Blanche M C Fishbein 《The Journal of heart and lung transplantation》1992,11(6):1110-1115
We used monoclonal antibodies and immunohistochemical staining of frozen tissue sections to study the expression of cytokines in human cardiac allograft rejection. The 113 endomyocardial biopsy samples were stained for interleukin (IL)-2, IL-6, and interferon-gamma. The findings were compared to expression of the endothelial cell adhesion molecule ICAM-1, and the lymphocyte receptor for the adhesion molecule VCAM-1, VLA-4. Four biopsy samples from patients with idiopathic cardiomyopathy served as controls. IL-2 was not expressed in lymphocytes of controls and only occasionally in mild or moderate cellular rejection, humoral rejection, and Quilty lesions. IL-2 expression was prominent in severe cellular rejection. Interferon-gamma expression increased in proportion to the severity of cellular rejection and was not expressed in other conditions. IL-6 staining, which was only observed in occasional cases, was mild. Cytokine and adhesion molecule expression tended to increase with the severity of cellular rejection. This study shows that cytokine expression can be documented in human allograft endomyocardial biopsy samples with immunohistochemical techniques. The findings support the concept of an important role for cytokines in human cardiac allograft rejection. 相似文献
117.
有一套系列恐怖畅销书叫做《鸡皮疙瘩丛书》,意思是故事恐怖到让看书人身上起满鸡皮疙瘩。可是,当你并不觉得寒冷或害怕时身上依然出现鸡皮疙瘩,那就代表着一种并不算恐怖却令许多女生苦恼不已的皮肤问题——毛周角化症。[编者按] 相似文献
118.
Monitoring the protective effects of minocycline treatment with radiolabeled annexin V in an experimental model of focal cerebral ischemia. 总被引:3,自引:0,他引:3
Xian Nan Tang Qing Wang Maya A Koike Danye Cheng Michael L Goris Francis G Blankenberg Midori A Yenari 《Journal of nuclear medicine》2007,48(11):1822-1828
Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia. 相似文献
119.
在初步开展了全英病理学教学后,我们认为提高教师的日常英语口语表达能力;用英语作为载体,重新构建教师的医学知识体系;要求学生课前认真预习;授课时尽可能多地采用图片,对采用全英语讲好病理学课大有裨益。 相似文献
120.
大肠埃希氏菌和肺炎克雷伯菌AmpC酶及ESBLs酶的检测及耐药性分析 总被引:4,自引:1,他引:3
目的:了解我院大肠埃希菌和肺炎克雷伯菌产AmpC酶和产ESBLs的情况及耐药性分析,为临床合理用药提供依据。方法:分别采用改良三维试验和CLSI/NCCLS推荐的纸片扩散法确证试验,检测大肠埃希菌和肺炎克雷伯菌产AmpC酶和产ESBLs菌株。结果:大肠埃希菌和肺炎克雷伯菌单产AmpC酶菌株检出率分别为9.3%和4%,单产ESBLs检出率分别为28%和12%,同时产AmpC酶及ESBLs检出率分别为14.7%和0。两种菌单产AmpC酶和单产ESBLs的菌株以及同时产两种酶的菌株对亚胺培南保持较低耐药率,均低于15%,而对其它类抗菌素大于50%,耐药率均较高。两种菌产酶株与不产酶菌株耐药率相比,均有显著性差异(P〈0.01)。结论:产酶株耐药情况严重,应慎重选择用药,减缓耐药菌株的进一步发生发展。 相似文献