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581.
目的探讨两种根管长度测量方法对根管充填质量的影响。方法随机选择需行根管治疗术的单根管恒前牙352颗,随机分为A、B两组,A组采用TRRY根管测量仪测量根管长度,根管预备后加试主尖摄牙片,侧方加压充填根管,摄牙片;B组采用根管器械探测法测量根管长度,根管预备后加试主尖摄牙片,侧方加压充填根管,摄牙片。结果在实际工作长度±1.0范围内,TRRY测量准确率为94.32%,根管器械探测法测量准确率为78.40%,两种方法差异显著(P<0.01)。适充率:A组90.37%,B组75.82%,两种方法充填根管X片结果差异显著(P<0.01),A组明显优于B组。结论用TRRY根管测量仪加试主尖摄牙片的方法可明显提高根管充填的质量,值得临床推广应用。 相似文献
582.
目的 本文总结了56例心脏肿瘤外科治疗经验及体会。方法 所有患者均在体外循环下进行肿瘤切除,心肌保护方法采用温血心麻液连续灌注,如果肿瘤侵犯心脏重要的组织结构应该做姑息切除,以免出现严重的并发症。结果 心脏良性肿瘤54例,其中53例为心脏黏液瘤,1例为心脏脂肪瘤,心脏恶性肿瘤2例,均为肉瘤。良性肿瘤均能彻底切除。术后心功能能迅速恢复,长期随访无复发,有良好的临床效果。恶性肿瘤不能彻底切除,手术效果差,术后并发症多。结论 心脏肿瘤是性黏液瘤多见,手术效果好。心脏恶性肿瘤以肉瘤多见,因广泛侵润难以彻底切除。 相似文献
583.
目的探讨大鼠同种异体骨髓单个核细胞(bone marrow mononuclear cells,BM—MNCs)在急性心肌梗死区分化增殖潜能及其修复重建心肌作用。方法健康雄性Wistar大鼠24只,用结扎冠状动脉左前降支的方法建立大鼠心肌梗死模型,随机分为对照组(AMI+培养基,12只),移植组(AMI+BM—MNCs,12只);分别将制备的培养基和BM—MNCs悬液心外膜下植入梗死心肌周围。移植术后4周,观察心肌梗死区及其周边区组织形态学特点、心肌梗死面积变化。结果实验组与对照组相比心肌梗死面积明显缩小(P〈0.01);实验组心肌梗死区内有BrdU标记阳性的BM—MNCs移植细胞存活,向心肌源性细胞分化并且诱导了大量的新生毛细血管。结论同种异体BM—MNCs移植在细胞水平完成了对心肌梗死区再心肌化和再血管化过程,可以改善急性心肌梗死后的心脏功能。 相似文献
584.
The clinical effects of dosage during the period of treatment of Lithospermum Ruderale extract-a kind of Chinese traditional herbal medicine-on medicinal abor tion induced by mifepristone and misoprostol were studied. Lithospermum Ruderale extract was administrated 3 d before, 3 d after or 3 d before plus 3 d after the admin istration of misoprostol respectively. The dose of Lithospermum Ruderale extract was 50 g, 75 g or 100g respectively. Thus 1 350 women of early pregnancy were grouped into 9 groups and observed. The results showed that the effects of Lithospermum Rud erale used 3 d before, and 3 d before plus 3 d after (6 days misoprostol were signifi cantly better than those only used 3 d after misoprostol both for complete abortion and bleeding (P<0.05). The dosage between 50 g and l00 g made no significant differ ence in clinical effects. Therefore it is reasonable to use 50 g Lithospermum Ruderale before misoprostol to improve medicinal abortion. 相似文献
585.
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587.
Hepatitis C virus (HCV) is a major cause of transfusion-induced chronic liver disease in hemophiliacs, with 70% to 90% being anti-HCV positive. Seroreversion or loss of antibody response to HCV has been observed in a small proportion of human immunodeficiency virus-positive [HIV(+)] anti-HCV(+) hemophilic men. Despite the seroreversion to an anti-HCV- negative state, such patients continue to show serum alanine aminotransferase (ALT) elevations and biopsy evidence of cirrhosis and/or chronic active hepatitis. To determine the cause for the loss of anti-HCV antibody, we compared first- and second-generation anti-HCV enzyme immunosorbent assay (EIA 1.0 and 2.0), second-generation recombinant immunoblot (RIBA 2.0), and HCV-RNA amplification using polymerase chain reaction (PCR) in 19 "seroreverters" before and after seroreversion. There was no difference between 19 seroreverters and 59 persistently anti-HCV-positive hemophiliacs in mean ALT (1.1 +/- 0.1 XUL v 2.0 +/- 0.2 XUL; chi 2 = 1.80, P > .05), in mean CD4 (188 +/- 36/microL v 232 +/- 28/microL; t = 0.965, P > .05), or in the rate of progression to acquired immunodeficiency syndrome (13 of 19 [68.4%] v 30 of 59 [50.9%]; chi 2 = .987, P > .05, respectively). Before seroreversion, all 19 seroreverters (100%) were positive for EIA 1.0 and 2.0 and PCR, and all but 2 of 19 (89.5%) were RIBA 2.0 positive, whereas, after seroreversion, none were positive for EIA 1.0, 15 of 19 (78.9%) were positive for EIA 2.0, 8 of 18 (44.4%) were positive for RIBA 2.0, and 18 of 19 (94.7%) were positive for PCR. There was a lower CD4 lymphocyte number after seroreversion in those who were RIBA 2.0 negative as compared with those who were RIBA 2.0 positive (32 +/- 10/microL v 171 +/- 52/microL; t = 2.638, P > .05). These results indicate that HIV(+) anti-HCV(+) hemophilic men who undergo "HCV seroreversion" are truly infectious and anti-HCV positive by second- generation tests. Anti-HCV detection in immunosuppressed hosts is significantly improved by second-generation EIA and RIBA assays. 相似文献
588.
目的观察骨髓单个核细胞(bone marrowmononuclear cells,BM-MNCs)移植对大鼠急性心肌梗死(AMI)后心肌细胞凋亡的影响。方法健康雄性Wistar大鼠30只,随机均分为实验组和对照组。用结扎冠状动脉左前降支的方法建立大鼠AMI模型,将制备的BM-MNCs悬液和培养液分别经心外膜下植入实验组和对照组梗死心肌周围。移植术后4周末,检测心肌细胞凋亡情况及Bcl-2、Fas、FasL蛋白在心肌细胞中表达水平,并观察梗死区心肌内移植BM-MNCs及其周边区组织形态学特点。结果移植后4周末,实验组心肌细胞凋亡指数显著低于对照组(P<0.05);与对照组相比,实验组Bcl-2蛋白吸光值显著升高(P<0.05),Fas、FasL蛋白吸光值显著降低(P<0.05);实验组心肌梗死区内有BrdU标记阳性的BM-MNCs存活。结论同种异体大鼠BM-MNCs移植可调节Bcl-2、Fas、FasL蛋白表达,抑制AMI后心肌细胞凋亡发生。 相似文献
589.
Pseudo-obstruction of the Colon 总被引:5,自引:0,他引:5
IAN A. SPIRA M.B. Ch.B. F.R.C.S. F.G.S. FA.G.S. F.A.C.G. ROBERTO RODRIGUES M.D. WILLIAM I. WOLFF M.D. F.A.C.S. F.A.C.G. 《The American journal of gastroenterology》1976,65(5):397-408
"Pseudo-obstruction of the colon" refers to a condition in which physical and radiological findings identical to those associated with mechanical obstruction of the large bowel are found but in which no organic cause for the colonic distention is present. These cases may involve progressive proximal large bowel dilatation to the point of cecal perforation or necrosis.
We have collected eight cases of our own which will be presented. The various etiologic factors reported in the literature will be discussed and analyzed and we will offer an anatomicophysiologic explanation of a possible mechanism, based on sympathetic-parasympathetic neurostimulatory imbalance. 相似文献
We have collected eight cases of our own which will be presented. The various etiologic factors reported in the literature will be discussed and analyzed and we will offer an anatomicophysiologic explanation of a possible mechanism, based on sympathetic-parasympathetic neurostimulatory imbalance. 相似文献
590.