全文获取类型
收费全文 | 266065篇 |
免费 | 21181篇 |
国内免费 | 9181篇 |
专业分类
耳鼻咽喉 | 2037篇 |
儿科学 | 8585篇 |
妇产科学 | 1737篇 |
基础医学 | 25109篇 |
口腔科学 | 10540篇 |
临床医学 | 27712篇 |
内科学 | 61221篇 |
皮肤病学 | 2884篇 |
神经病学 | 26999篇 |
特种医学 | 8410篇 |
外国民族医学 | 27篇 |
外科学 | 25510篇 |
综合类 | 36581篇 |
现状与发展 | 37篇 |
一般理论 | 9篇 |
预防医学 | 20014篇 |
眼科学 | 2560篇 |
药学 | 17370篇 |
216篇 | |
中国医学 | 11321篇 |
肿瘤学 | 7548篇 |
出版年
2024年 | 788篇 |
2023年 | 5363篇 |
2022年 | 9597篇 |
2021年 | 13598篇 |
2020年 | 12904篇 |
2019年 | 10046篇 |
2018年 | 9801篇 |
2017年 | 9873篇 |
2016年 | 10139篇 |
2015年 | 10053篇 |
2014年 | 18463篇 |
2013年 | 20912篇 |
2012年 | 15118篇 |
2011年 | 16532篇 |
2010年 | 13243篇 |
2009年 | 12664篇 |
2008年 | 12563篇 |
2007年 | 12266篇 |
2006年 | 10918篇 |
2005年 | 9279篇 |
2004年 | 7971篇 |
2003年 | 6894篇 |
2002年 | 5809篇 |
2001年 | 5066篇 |
2000年 | 4188篇 |
1999年 | 3635篇 |
1998年 | 3361篇 |
1997年 | 3037篇 |
1996年 | 2734篇 |
1995年 | 2381篇 |
1994年 | 2236篇 |
1993年 | 1829篇 |
1992年 | 1780篇 |
1991年 | 1535篇 |
1990年 | 1233篇 |
1989年 | 1083篇 |
1988年 | 981篇 |
1987年 | 877篇 |
1986年 | 769篇 |
1985年 | 913篇 |
1984年 | 745篇 |
1983年 | 491篇 |
1982年 | 574篇 |
1981年 | 472篇 |
1980年 | 370篇 |
1979年 | 334篇 |
1978年 | 278篇 |
1977年 | 226篇 |
1976年 | 194篇 |
1975年 | 84篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
151.
目的:分析肺心病合并脑梗死的临床特点.方法:对39例肺心病合并脑梗死患者的临床资料进行回顾性分析.结果:肺心病合并脑梗死发病率6.2%,48小时内确诊率48.7%.结论:肺心病合并脑梗死临床表现不典型,及时确诊困难. 相似文献
152.
Manuel Sosa P. Saavedra J. del Pino-Montes J. Alegre R. Pérez-Cano G. Martínez Díaz Guerra M. Díaz-Curiel C. Valero M. Muñoz-Torres A. Torrijos J. Mosquera C. Gómez-Alonso GIUMO Study Group 《Journal of clinical densitometry》2005,8(4):430-435
Measurement of ultrasonographic parameters provides information concerning not only bone density but also bone architecture. We investigated the usefulness of ultrasonographic parameters and bone mineral density (BMD) to evaluate the probability of Colles' fracture. Two-hundred eighty-nine postmenopausal women (62.3 +/- 8.7 yr) with (n = 76) and without (n = 213) Colles' fracture were studied. BMD of lumbar spine and proximal femur was evaluated in all women by dual-energy X-ray absorptiometry (DXA) and speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness in the calcaneus were measured by a Sahara ultrasonometer (Hologic). Patients suffering from Colles' fracture had lower values of BMD adjusted by height at the lumbar spine, L2-L4 (0.797 g/cm2 vs 0.860 g/cm2), femoral neck (0.685 g/cm2 vs 0.712 g/cm2 ), SOS (1518 m/sg vs 1525 m/sg), and stiffness (74.6 vs 77.7) (p < 0.05). Nevertheless, BUA values were similar in both groups. After stepwise logistic regression analysis, the area found under receiver operating characteristic (ROC) curves was 0.60 for L2L4 and 0.63 for a formula combining L2L4 and height. Our data suggest that patients suffering from Colles' fracture have lower values of BMD by DXA, SOS, and stiffness. However, the ability of these techniques to discriminate is low because the values for the area under ROC curve are 0.60 for L2-L4 and 0.63 for a formula derived of the combination of L2-L4 and height. 相似文献
153.
Holger F. Boehm Felix Eckstein Caecilia Wunderer Volker Kuhn Eva-Maria Lochmueller Karin Schreiber Dirk Mueller Ernst J. Rummeny Thomas M. Link 《Journal of clinical densitometry》2005,8(4):488-494
We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL. 相似文献
154.
后腹腔镜下离断式肾盂成形术 总被引:2,自引:0,他引:2
目的探讨后腹腔镜下肾盂成形术的临床疗效. 方法腹腔镜下通过后腹腔途径对9例肾盂输尿管连接部狭窄行离断式肾盂成形术并对技术进行改进. 结果 9例手术均获成功,手术时间110~240 min,平均160 min.术中出血量30~80 ml,平均50 ml.术后住院8~18 d,平均11.2 d.术后并发症:皮下气肿(合并阴囊气肿)1例,漏尿2例.术后1~10个月B超示术侧肾盂无积水5例,轻度积水2例,中度积水2例.3例术后5个月IVU显示吻合口通畅. 结论后腹腔镜肾盂成形术微创、效果好,值得推广. 相似文献
155.
蒋丽君 《中国中医药信息杂志》2005,12(9):17-18
目的观察按压骨穴对围绝经期妇女心脏植物神经功能的影响。方法设按压骨穴组30例、空白对照组30例。用美国BraemarDL700型动态心电检测仪,检测试验前后的心率变异性(HRV):TF代表总频,LF代表交感神经活性,HF代表迷走神经活性,LF/HF代表交感神经与迷走神经均衡性。结果按压骨穴后4项指标均有显著下降(P<0.01,P<0.05)。空白对照组变化不显著(P>0.05)。骨穴组4项指标的变化率与对照组比较均有显著性差异(P<0.01)。结论按压骨穴有抑制心脏交感神经活性的良性调整作用,此效应具有相对的特异性。 相似文献
156.
目的探讨小剂量阿司匹林与银可络联用对老年患者血液流变学异常的影响。方法57例老年病人并伴有高凝、高粘血症者采用小剂量阿司匹林50mg,口服,1次/d,银可络80mg,口服,3次/d。疗程为1个月。并测定治疗前后血液流变学各项参数。结果病例组治疗后血小板粘附率(PadT)、血栓长度、重量与对照组比较均有显著性差异(P均<0.01);治疗后红细胞刚性指数(IR)、血沉(ESR)、红细胞电泳时间(EFT)、全血表现粘度(BAV)与治疗前比较均有显著性差异(P均<0.001);病例组治疗后红细胞比积(HCT)、纤维蛋白原(Fib)、血浆比粘度(PV)与对照组比较均无显著性差异(P均>0.05)。结论小剂量阿司匹林与银可络联合治疗对血栓形成过程有抑制作用,红细胞变形能力和聚集性有所改善。但对Fib,PV,HCT无影响。 相似文献
157.
L. C. Scott G. K. Wright G. S. Rai A. N. Exton-Smith J. M. Gardiner 《International journal of geriatric psychiatry》1991,6(8):583-588
Memory performance of elderly patients in the early stages of Alzheimer's disease (DAT) was compared with that of elderly control subjects. In explicit tests of recognition memory, which involve conscious recollection, the DAT patients were grossly impaired. In implicit tests of anagram solution and wordstem completion, which do not require conscious recollection, the DAT patients were not impaired. These findings further support the idea that a separate memory system, episodic memory, underlies conscious recollection, that it is this system which is most commonly damaged in amnesia, and that memory systems not involving conscious recollection may be spared in the early stages of Alzheimer's disease. 相似文献
158.
Borras Merce; Valdivielso Jose M.; Egido Ramon; Vicente de Vera Pilar; Bordalba Josep Ramon; Fernandez Elvira 《Nephrology, dialysis, transplantation》2006,21(3):789-791
159.
160.
本系统通过以Internet网为平台,将传统的医院/患者(咨询者)的遗传随访模式转为医院/Internet网/患者(咨询者)的新医疗模式,该系统会大大提高遗传随访的及时性和便利性;同时,会有利于遗传登记的开展,也有利于随访资料的保存。 相似文献