全文获取类型
收费全文 | 82037篇 |
免费 | 7496篇 |
国内免费 | 5491篇 |
专业分类
耳鼻咽喉 | 844篇 |
儿科学 | 897篇 |
妇产科学 | 1224篇 |
基础医学 | 10591篇 |
口腔科学 | 1411篇 |
临床医学 | 10968篇 |
内科学 | 12409篇 |
皮肤病学 | 1029篇 |
神经病学 | 4500篇 |
特种医学 | 3166篇 |
外国民族医学 | 53篇 |
外科学 | 8535篇 |
综合类 | 10792篇 |
现状与发展 | 21篇 |
一般理论 | 22篇 |
预防医学 | 5139篇 |
眼科学 | 2990篇 |
药学 | 8476篇 |
67篇 | |
中国医学 | 4162篇 |
肿瘤学 | 7728篇 |
出版年
2024年 | 258篇 |
2023年 | 1217篇 |
2022年 | 3173篇 |
2021年 | 4090篇 |
2020年 | 3011篇 |
2019年 | 2889篇 |
2018年 | 3072篇 |
2017年 | 2546篇 |
2016年 | 2653篇 |
2015年 | 3806篇 |
2014年 | 4727篇 |
2013年 | 4169篇 |
2012年 | 6176篇 |
2011年 | 6613篇 |
2010年 | 4090篇 |
2009年 | 3089篇 |
2008年 | 4290篇 |
2007年 | 4168篇 |
2006年 | 4252篇 |
2005年 | 4089篇 |
2004年 | 2774篇 |
2003年 | 2538篇 |
2002年 | 2087篇 |
2001年 | 1798篇 |
2000年 | 1775篇 |
1999年 | 2063篇 |
1998年 | 1321篇 |
1997年 | 1294篇 |
1996年 | 972篇 |
1995年 | 926篇 |
1994年 | 776篇 |
1993年 | 497篇 |
1992年 | 597篇 |
1991年 | 504篇 |
1990年 | 476篇 |
1989年 | 424篇 |
1988年 | 383篇 |
1987年 | 307篇 |
1986年 | 260篇 |
1985年 | 221篇 |
1984年 | 140篇 |
1983年 | 87篇 |
1982年 | 49篇 |
1981年 | 58篇 |
1980年 | 34篇 |
1979年 | 69篇 |
1978年 | 22篇 |
1977年 | 19篇 |
1976年 | 22篇 |
1974年 | 27篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
Z-Y Sun J Wei L Xie Y Shen S-Z Liu G-Z Ju J-P Shi Y-Q Yu X Zhang Q Xu G P Hemmings 《European psychiatry》2004,19(6):354-357
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3'-untranslated region of the CLDN5 locus was associated with schizophrenia (chi(2) = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5'-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (chi(2)) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (chi(2) = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors. 相似文献
142.
双侧内囊前肢毁损术治疗难治性强迫症疗效及随访研究 总被引:9,自引:0,他引:9
目的 对难治性强迫症进行双侧内囊前肢毁损术治疗 ,评定手术疗效并进行 2年随访 ,以进一步探索脑外科手术对难治性强迫症的疗效 ,并探讨手术治疗的良好适应症。方法 对 2 8例难治性强迫症患者进行双侧内囊前肢毁损术治疗 ,并分别在手术前、手术后二周、手术后三月、手术后六月、手术后一年、手术后二年进行Y BOCS、HAMA、HAMD量表评定及术后疗效评定。结果 (1)强迫症患者手术后各期Y BOCS评分、HAMA评分与手术前比较均下降 ,有极显著差异 (P <0 .0 0 1) ;(2 )手术后各期Y BOCS的强迫思维评分均有明显下降 (P <0 .0 0 1) ,强迫行为在手术后 1年和 2年 ,与手术前比较无明显改变 (P >0 .0 5 ) ;(3)手术后 2年的总有效率为 5 3.5 % ,明显低于手术后 3月的总有效率 (P <0 .0 1)。结论 采用双侧内囊毁损术有相当的治疗效果 ,对于难治性强迫症患者可作为一种补充治疗手段 ;手术治疗对强迫行为的长期疗效较差 ,以严重的强迫思维为主的难治性强迫症患者为手术更好的适应症。 相似文献
143.
左半结肠癌并发急性肠梗阻一期切除吻合的合理性与评价 总被引:21,自引:3,他引:18
目的 探讨左半结肠癌并发急性肠梗阻一期切除吻合的合理性与评价。方法 回顾性分析我院1994年2月期间至2003年2月采用一期切除吻合术治疗左半结肠癌并发急性肠梗阻64例的l临床资料。结果 全组患者无死亡及腹腔感染。7例(10.9%)发生切口感染,3例(4.7%)发生吻合口漏,均治愈。住院时间10~36d,平均16d。结论 部分经选择的病例中开展一期切除吻合术是安全、可行的,选择性应用一期切除吻合术是治疗左半结肠癌并发急性肠梗阻的理想术式。 相似文献
144.
We describe the enhancement patterns of myoepithelioma in two patients with a soft palate mass. In the first case, helical CT revealed a faintly enhancing mass. Histologically, the tumor was composed of plasmacytoid cells in a background of rich myxoid stroma. Immunostaining for CD34 showed scanty blood vessels. In the second case, helical CT revealed an intensely enhancing mass. Histologically, the mass was a cellular tumor with fibrous stroma. Immunostaining for CD34 also showed frequent blood vessels. 相似文献
145.
Objective: To summarize the clinical outcomes of 117 human vitrified blastocyst transfer cycles and to determine the impact factors.Methods: In IVF-ET cycles, supernumerary embryos were cultured to 5-Day(D5) or 6-Day(D6), blastocysts of various stages were cryopreserved by vitrification using cryoloops. Survival rate and clinical pregnancy rate were observed.Results: A total of 312 blastocysts were thawed in 117 frozen embryo transfer cycles, the survival rate was 90.7% (283/312) after thawing. After the transfer of 230 blastocysts in 115 cycles, 69.6% (80/115) of the women got clinically pregnant, and 17.5% (14/80) of them suffered from miscarriage, 39 healthy babies were born in 28 deliveries, and the other 38 pregnancies are ongoing. The implantation rate was 47.4% (109/230). In 107 transfer cycles with 2 hatched blastocysts transferred in each cycle, 72.9% (78/107) got clinically pregnant, while in 8 cycles with 1 or no hatched blastocysts in the two transferred blastocysts, the clinical pregnancy rate is 25%(2/8). The clinical pregnancy rates were not statistically different between natural (77.4%, 24/31) or artificial endometrium preparation (66.7%, 56/84) cycles. Conclusions: These findings suggest that blastocyst vitrification is effective in terms of implantation rate and pregnancy outcome. Transferring of two hatched blastocyst can achieve a higher pregnancy rate. 相似文献
146.
目的:研究脑缺血后脑片[Ca2+]i变化。方法:采用新型Ca2+荧光指示剂Fura-2双波长法测定兔大脑中动脉阻塞(MCAo)局灶脑缺血后脑片细胞内游离钙([Ca2+]i)。结果:脑缺血后脑组织[Ca2+]i显著升高。结论:[Ca2+]i在脑缺血损害中起重要作用。 相似文献
147.
以地高辛甙元随机引物法标记HBV-DNA探针,以此探针检测慢性乙型肝炎患者的血清、肝组织,同时以ELISA法检测血清HBeAg、HBcAb。结果:血清NBeAg阳性率27%(10/37),血清HBV-DNA检出率57.1%(20/35),两者有显著性差异。血清HBcAb阳性率78.4%(29/37),肝组织HBV-DNA检出率83.8%(31/37),两者无显著性差异。血清与肝组织HBV-DNA检出率有显著性差异。提示:血清HBV-DNA检测是较HBeAg更为准确客观反映血液带毒状况的指标。而准确反映肝脏带毒状况的指标是肝组织HBV-DNA检测。当HBeAg阴转,血清HBV-DNA阴性而肝组织HBV-DNA阳性时,需注意肝硬化及肝癌的发生。 相似文献
148.
股骨头缺血坏死的低场MRI评价 总被引:9,自引:1,他引:8
目的: 分析股骨头缺血坏死(ANFH)低场MRI征象,评价ANFH的MRI分期及其关节积液的分级.材料和方法:在分析50例正常髋MRI基础上回顾性对照分析51例(90个股骨头)ANFH的低场MRI和X线平片资料.结果:90个ANFH中,20个(22 %) X线平片为阴性;64个(71%)MRI示"脂肪强度征"即坏死区内或近侧可见类似皮下脂肪样信号.按照 Hungerford分期:0期9个,Ⅰ期13个,Ⅱ期31个,Ⅲ期26个,Ⅳ期11个.ANFH引起的关节积液多为2~3级(60个髋,占67%);Ⅲ、Ⅳ期ANFH合并关节积液量比0~Ⅱ期明显多(P<0.005).结论:低场MRI能够准确显示ANFH的范围、程度、信号特征及其关节积液的情况,并能够对早期ANFH作出可靠诊断;"脂肪强度征"为低场MRI的特征性表现,对诊断ANFH有非常重要的价值. 相似文献
149.
150.
Jiyou Li Yuquan Xie Guizhi Shi Heling Sun Xinhua Ji Maolin Jin Boqin Yang Mingsheng Wang 《中国癌症研究》1992,4(2):10-12
In order to investigate the antagonistic effect of Glycyrrhiza Uralensis Fish (GUF) and Chelidonium maJus L (CML) on gastrccarcinogenesis
induced by MNNG in Wastar rats, we treated the rats with MNNG alone (group 1) and with MNNG plus GUF and CML (group 2 and
3) respectively. The incidence of infiltrating adenocarcinoma of the glandular stomach and duodenum in group 2 was significantly
lower than that in group 1 (26.7% vs. 67.8%). The differentiation and aggressivenees of carcinomas occured in group 2 were
much better and mild than those in group 1. Present study also demonstrated that the inhibitory effect of CML on proliferation
of human stomach carcinoma cell line MGC-803 was very remarkable; in addition, GUF and CML were able to antagonise the mutagenic
activation of MNNG. These results suggest that GUF and CML may be empoyed in prevention of gastric carcinoma. 相似文献