全文获取类型
收费全文 | 87772篇 |
免费 | 7795篇 |
国内免费 | 5538篇 |
专业分类
耳鼻咽喉 | 882篇 |
儿科学 | 1185篇 |
妇产科学 | 665篇 |
基础医学 | 6820篇 |
口腔科学 | 1308篇 |
临床医学 | 10760篇 |
内科学 | 8954篇 |
皮肤病学 | 1026篇 |
神经病学 | 2615篇 |
特种医学 | 3255篇 |
外国民族医学 | 16篇 |
外科学 | 7549篇 |
综合类 | 21993篇 |
现状与发展 | 24篇 |
一般理论 | 1篇 |
预防医学 | 9461篇 |
眼科学 | 1808篇 |
药学 | 10769篇 |
130篇 | |
中国医学 | 7595篇 |
肿瘤学 | 4289篇 |
出版年
2024年 | 303篇 |
2023年 | 985篇 |
2022年 | 2627篇 |
2021年 | 3390篇 |
2020年 | 2977篇 |
2019年 | 1899篇 |
2018年 | 2006篇 |
2017年 | 2542篇 |
2016年 | 2061篇 |
2015年 | 3573篇 |
2014年 | 4675篇 |
2013年 | 5379篇 |
2012年 | 7806篇 |
2011年 | 8482篇 |
2010年 | 7083篇 |
2009年 | 6197篇 |
2008年 | 6730篇 |
2007年 | 6361篇 |
2006年 | 5782篇 |
2005年 | 4611篇 |
2004年 | 3438篇 |
2003年 | 2911篇 |
2002年 | 2391篇 |
2001年 | 1939篇 |
2000年 | 1530篇 |
1999年 | 861篇 |
1998年 | 441篇 |
1997年 | 427篇 |
1996年 | 340篇 |
1995年 | 278篇 |
1994年 | 286篇 |
1993年 | 143篇 |
1992年 | 146篇 |
1991年 | 128篇 |
1990年 | 63篇 |
1989年 | 56篇 |
1988年 | 65篇 |
1987年 | 51篇 |
1986年 | 30篇 |
1985年 | 36篇 |
1984年 | 24篇 |
1983年 | 6篇 |
1982年 | 12篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1974年 | 5篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1949年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
本中心对129例经腹腔镜证实为美国生殖医学会(ASRM)II-IV期子宫内膜异位症(内异症)合并其他不育因素而行体外受精-胚胎移植(IVF-ET)治疗的病例,进行了回顾性统计和分析。一、资料和方法1.临床资料:从2005年4月至2007年3月,在本中心接受IVF-ET治疗经腹腔镜证实为ASRMII-IV期内异症合并其他不育因素的129个周期病例;对照组为输卵管性不育的1,543个周期。内异症组根据有无促性腺激素释放激素激动剂(GnRH-a)药物降调节分为A、B两组进行分析,A组:中重度内异症在手术后接受长效GnRH-a(3.75 mg/支,每28 d一支,共2~6支)抑制治疗的39个… 相似文献
62.
环缩酚肽抑制视网膜表达VEGF及PECAM基因和血管增生 总被引:2,自引:0,他引:2
[目的]观察两种环缩酚肽衍生物(Hep-A和Hep-B)对氧诱导的小鼠视网膜表达血管内皮生长因子(VEGF)和细胞黏附分子(PECAM;ICAM-1;VCAM-1)基因的影响及血管增生的变化.[方法]建立氧诱导的血管增殖性视网膜病变模型,12 d开始给小鼠皮下注安慰剂(第1组,n=7)、Hep-A 10 mg/kg(第2组,n=6)或者Hep-B 10 mg/kg(第3组,n=6),每天两次.5 d后取出左侧眼,分离视网膜并抽提RNA,用荧光定量PCR测出上述基因含量,并分别求出每个靶基因与标准基因S16含量的比率;右眼经心脏荧光素灌注后取眼球做视网膜平铺片,用图像分析软件定量计算视网膜新生血管的面积.[结果]视网膜中VEGF/S16的mRNA比率为:第1组(0.554±0.050),第2组(0.355±0.037),第3组(0.287±0.051);PECAM/S16为:第1组(2.050±0.249),第2组(1.228±0.153),第3组(1.027±0.210).经ANOVA分析,第2组和第3组分别与第1组比较,视网膜中VEGF基因表达分别减少36%和48.2%(P=0.001);PECAM基因表达分别减少40.1%(P<0.05)和49.9%(P<0.01);而VCAM-1和ICAM-1表达无明显差异.视网膜平片检测视网膜新生血管面积:第1组为(1.06±0.03)mm2/眼,第2组为(0.17±0.01)mm2/眼,第3组为(0.11±0.01)mm2/眼;经ANOVA分析,第2组和第3组分别与第1组比较,视网膜新生血管的面积明显减少(P<0.001).[结论]两种环缩酚肽衍生物均抑制氧诱导的小鼠视网膜表达VEGF和PECAM基因,并抑制其形成视网膜新生血管. 相似文献
63.
目的探讨术中应用前列腺素E1(prostaglandin E1,PGE1)对大鼠肝移植肾功能的保护作用。方法大鼠原位肝移植术中经颈内静脉灌注PGE1为治疗组,生理盐水和空白为对照组,观察术后1周存活率、1h的尿量,测定血浆肌酐、尿素氮和肾组织中丙二醛(malondjaldehyde,MDA)、谷胱甘肽(glutathione,GSH)含量,肾组织病理检查。结果PGE1治疗组术后1h尿量较对照组明显增加,肌酐和尿素氮水平均较对照组降低,PGE1治疗组肾组织中GSH含量显著高于两对照组,MDA含量低于两对照组。病理检查PGE1治疗组肾脏组织形态学损伤明显减轻。结论术中应用PGE1能显著改善大鼠肝移植后的肾功能,其机制可能与对抗氧自由基损伤作用有关。 相似文献
64.
65.
下前牙桩核冠三维有限元模型的建立 总被引:1,自引:0,他引:1
目的:建立桩核冠修复后的下颌中切牙及其牙周支持组织的三维有限元模型。方法:利用薄层CT技术、UG软件与ALGOR软件相结合,对层厚为0.2mm的CT断层影像进行分析处理。结果:模型共有单元45153个,节点27763个,可以根据要求任意旋转、缩放、透视、剖开,进行多种方式观察;并可以按照不同研究目的,对模型进行修改和调整,来模拟不同程度牙槽骨吸收、联冠修复以及各种约束和加载条件下前牙的力学反应。结论:利用薄层CT扫描技术、UG自由曲面功能以及ALGOR软件相结合建立的三维有限元模型,能较精确地模拟临床口腔实际情况,为进一步研究下颌前牙不同牙周情况下的修复奠定了良好的基础。 相似文献
66.
严晓璐 《中国医疗器械信息》2006,12(1):77-77
2005年12月19日,中国安全注射联盟在北京召开了“安全注射在行动研讨会”(图1),会议得到了卫生部,国家食品药品监督管理局、联合国儿童基金会,世界卫生组织等政府部门的的支持,中国医疗器械行业协会作为此次会议的协办单位和90多位来自“联盟”成员的专家、教授、学会、协会、基金会领导和企业高层管理人员进行了积极的研讨。 相似文献
67.
Luan Shu Zi- Chun Hua 《中国药理通讯》2006,23(3):30-30
Triptolide is potent immunosuppressive has been reported to inhibit autoimmunity, compound isolated from Chinese herbal medicine. Triptolide allograft attributed to the suppression of T cells via NF - kB rejection and GVHD, and its efficacy was previously pathway and apoptosis. In the present study, we detailedly analyzed Triptolide' s function on murine primary T cell. We found that Triptolide could inhibit T cell activation and proliferation by dramatically down - regulating cell division and cell cycle. Triptolide inhibited T cell activation in a dose- dependent manner, and the inhibition was mediated by both NF- kB pathway and AP - 1 pathway. 相似文献
68.
Objective To investigate the effects of intensive insulin therapy on inflammatory re-sponse and prognosis of patients with severe trauma. Methods Eighty severely injured patients were di-vided into intensive insulin therapy group (n = 40, IT) and routine therapy group (n = 40, RT) in random pair. At the time of admission, a continuous infusion of insulin (2 -4 U/h) was pumped into the patients of IT group to maintain blood glucose level at 6 -8 mmol/L. Patients in RT group were given routine treatment without administration of insulin. Fever, organ injury, and mortality of patients in 2 groups were recorded. Venous blood was drawn from patients of 2 groups on the morning of post treatment day (PTD) 1, 3, 5, and 7. Values of TNF-α, C-reactive protein (CRP), IL-2, and IL-10 in plasma were assayed. Results High fever appeared in 9 patients in IT group, and WBC exceeded 10.0×109 for more than 3 days in 17 patients in this group, versus 20 and 29 patients respectively in RT group. Dysfunction of 1 organ appeared in 31 pa-tients in IT group and 30 patients in RT group. Dysfunction of 3 organs appeared in 10 patients in IT group and 19 patients in RT group. Dysfunction of 4 organs appeared in 7 patients in IT group and 12 patients in RT group. In IT group, 4 patients died within 3 post-injury day (PID), and 1 patient died after PID 3 (total case fatality: 12.5% ). In RT group, 5 patients died within 3 PID, and 4 patient died after PID 3 (total case fatality: 22.5%). Plasma levels of TNF-α and CRP of patients in IT group were significantly lower than those of patients in RT group on PID 3 - 7 ( P<0.05 or P<0.01 ), while levels of IL-2 and IL-10 of patients in IT group were significantly higher than those of patients in RT group ( P<0.05 or P<0.01 ). Plasma levels of TNF-α ( 1.3±0.6 μg/L) and CRP (55±16 mg/L) of patients in IT group on PTD 7 were lowered to the trough level, and they were significantly lower than those of patients in RT group (3.0±0.8μg/L, 89±20 mg/L, respectively, P <0.01 ). Conclusions Intensive insulin therapy can mitigate systemic inflammatory response and improve prognosis of patients with severe trauma. 相似文献
69.
目的:探讨凝血因子ⅩⅢ(FⅩⅢ)Val34Leu基因多态性与中国人群深静脉血栓形成(DVT)发病的相关性.方法:利用聚合酶链反应和限制性片段长度多态性(PCR-RFLP)方法,检测了103例DVT患者与106例正常对照的FⅩⅢVal34Leu基因多态,并加以对照分析.结果:103例DVT患者FⅩⅢVa134Leu基因型均为野生型V/V,未见突变类型;106例对照组中发现1例突变杂合子V/L.2组基因型频率、等位基因频率相互比较,差异均无统计学意义(P>0.05).结论:FⅩⅢVal34Leu对中国人群DVT有保护作用的可能性极小. 相似文献
70.
Chang Hyun Lee Jung-Gi Im Jin Mo Goo Hyun Ju Lee Sung-Tae Hong Cheng Hua Shen Doo Hyun Chung Kyu Ri Son Jung Min Chang Hong Eo 《Korean journal of radiology》2007,8(5):372-381
OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus. 相似文献