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31.
In spite of great application potential as transparent n-type oxides with high electrical mobility at room temperature, threading dislocations (TDs) often found in the (Ba,La)SnO3 (BLSO) films can limit their intrinsic properties so that their role in the physical properties of BLSO films need to be properly understood. The electrical properties and electronic structure of BLSO films grown on SrTiO3 (001) (STO) and BaSnO3 (001) (BSO) substrates are comparatively studied to investigate the effect of the TDs. In the BLSO/STO films with TD density of ~1.32 × 1011 cm−2, n-type carrier density ne and electron mobility are significantly reduced, as compared with the BLSO/BSO films with nearly no TDs. This indicates that TDs play the role of scattering-centers as well as acceptor-centers to reduce n-type carriers. Moreover, in the BLSO/STO films, both binding energies of an Sn 3d core level and a valence band maximum are reduced, being qualitatively consistent with the Fermi level shift with the reduced n-type carriers. However, the reduced binding energies of the Sn 3d core level and the valence band maximum are clearly different as 0.39 and 0.19 eV, respectively, suggesting that the band gap renormalization preexisting in proportion to ne is further suppressed to restore the band gap in the BLSO/STO films with the TDs.  相似文献   
32.
经皮椎体注入骨水泥治疗老年脊椎骨质疏松压缩性骨折   总被引:4,自引:0,他引:4  
目的:观察经皮椎体内注入骨水泥(聚甲基丙烯酸甲酯)治疗脊椎骨质疏松压缩性骨折的疗效。方法:自2005-06/2006-06吉林大学中日联谊医院骨科及大庆龙南医院骨科对35例40个椎体的骨质疏松压缩性骨折患者使用经皮椎体内注射骨水泥,行椎体成形术。成形材料:美国KYPHON公司生产的骨水泥,生产准许号:(GB/T19001-2000和YY/T0287-1996)。结果:35例患者均参加随访6个月。术后均未出现骨水泥外漏、脊髓或马尾神经损伤等并发症。35例患者中5例出现穿刺部位局部疼痛,服用镇痛药物后均缓解。疼痛完全消失25例,占71.4%;明显缓解8例,占22.6%;轻度缓解2例,占6.0%;无缓解0例。15例患者在术后72h内均能下床活动。术后未再发生压缩性骨折及疼痛。结论:经皮椎体注入骨水泥可以有效改善椎体骨质疏松压缩性骨折患者疼痛症状,随访6个月未出现充填剂不良性宿主反应,临床疗效较好。  相似文献   
33.
BACKGROUND: Adenosine, a metabolite of adenosine triphosphate degradation during ischemia, is reported to attenuate ischemia and reperfusion injury in several tissues. Dipyridamole is a nucleoside transport inhibitor that augments endogenous adenosine. In this study, we tested whether dipyridamole would attenuate hepatic I/R injury. For this purpose, dipyridamole was applied to a 2-hour total hepatic vascular exclusion model in dogs. STUDY DESIGN: Dipyridamole (DYP) was given by continuous intravenous infusion for 1 hour before ischemia at a dose of 0.25 mg/kg (high-DYP, n = 6), 0.1 mg/kg (medium-DYP, n = 6), or 0.05 mg/kg (low-DYP, n = 6). Nontreated animals were used as ischemic controls (CT, n = 12). Two-week survival, systemic and hepatic hemodynamics, liver function tests, energy metabolism, adenosine 3', 5'-cyclic monophosphate (cyclic AMP) levels, platelet numbers, arachidonic acid metabolites, and histopathology were analyzed. RESULTS: Two-week animal survival was 25% in CT, 17% in high-DYP, 100% in medium-DYP, and 17% in low-DYP. Dipyridamole significantly improved postreperfusion hepatic blood flow and energy metabolism, attenuated liver enzyme release and purine catabolite production, and augmented cyclic AMP levels. The medium dose of dipyridamole lessened platelet aggregation, thromboxane B2 production, and polymorphonuclear neutrophil infiltration, and improved survival. CONCLUSIONS: We demonstrated marked hepatoprotective effects of dipyridamole against severe ischemia and reperfusion injury in canine livers. Dipyridamole is a promising agent for liver surgery and transplantation.  相似文献   
34.
Background: The strong comorbidity between substance use disorders (SUDs) and mood and anxiety disorders has been well documented. In view of lack of research findings addressing the co‐occurrence of SUDs and mood and anxiety disorders, this study examined the pattern of comorbidity of alcohol use disorders (AUDs) and nicotine dependence (ND) between 2 culturally diverse countries, the United States and South Korea. Methods: Using the nationally representative samples of the U.S. and Korean general populations, we directly compared rates and comorbidity patterns of AUDs, ND, and mood and anxiety disorders between the 2 countries. We further examined the rates and the comorbidity pattern among individuals with AUDs who sought treatment in the last 12 months. Twelve‐month prevalence rates were derived to estimate country differentials, and odds ratios (ORs) and 95% confidence intervals were estimated to measure the strength of comorbid associations while adjusting for all sociodemographic characteristics in multivariate logistic models specific to each country. Results: The 12‐month prevalence rates of AUDs, ND, and any mood disorder and any anxiety disorder were 9.7, 14.4, 9.5, and 11.9% among Americans, whereas the corresponding rates were 7.1, 6.6, 2.0, and 5.2% among Koreans. These rates were significantly greater (except for any AUD) among Americans than among their Korean counterparts. With respect to comorbidity, both countries showed comparable patterns that the prevalence rates of mood and anxiety disorders were consistently the highest among persons with alcohol dependence (AD). Also, a disparate pattern was observed in Korea that the prevalence rates of mood and anxiety disorders were generally lower among individuals with ND than among those with alcohol abuse and AD. Furthermore, despite significantly greater prevalence of AD in Korea (5.1%) than in the United States (4.4%), alcohol‐dependent Americans were 4 times (OR = 3.93) more likely to seek treatment compared to their Korean counterparts. Conclusions: Our results indicated that the prevalence of AD in Korea was substantially greater than that in both Western and other Asian countries, suggesting a maladaptive pattern of alcohol use in Korea, which is different from the general use pattern of other East Asian countries. The low rate of treatment utilization among Koreans might be attributable to perceived social stigma toward SUDs or mental health problems despite the fact that the Korean government offers national health insurance.  相似文献   
35.
异落新妇甙的结构研究   总被引:1,自引:0,他引:1  
李伊庆  易杨华  汤海峰  肖凯 《药学学报》1996,31(10):761-763
从百合科菝葵属植物土茯苓(Smilaxg labra Roxb.)根茎的乙醇提取物中分得一个新的天然化合物(I),命名为异落新妇甙(isoastilbin)。根据元素分析,UV,IR,1H-NMR,13C-NMR,2DNMR及FAB-MS,确定化合物I的结构为5,7,3',5'-四羟基二氢黄酮醇-3-O-α-L-鼠李糖甙。  相似文献   
36.
目的:观察由内皮素1激活的内皮素A受体对家兔动脉粥样硬化斑块环氧合酶2表达的影响。方法:实验于2006-03/09在上海交通大学医学院附属新华医院科研中心完成。①实验分组:32只雄性新西兰大白兔完全随机设计分成基础组、模型组、BQ-123组以及辛伐他汀组,每组8只。②实验方法:基础组饲喂普通饲料10周,其余3组均饲喂高脂饲料(1%胆固醇、10%蛋黄粉、5%猪油、84%普通饲料)10周。模型组于第6周开始静脉注射生理盐水(4mL/d)连续注射5周,作为阴性对照;BQ-123组于第6周开始用微量输液泵静脉点滴选择性内皮素A受体拮抗剂BQ-123(4mL/d,30min滴完),连续点滴5周;辛伐他汀组于第6周开始添加药物饲料(含辛伐他汀10mg/d)连用5周。③实验评估:饲喂10周后,采耳动脉血检测血清总胆固醇、三酰甘油、高密度脂蛋白胆固醇以及低密度脂蛋白胆固醇水平;采用免疫组织化学SP法检测主动脉标本中组织内皮素1、巨噬细胞及环氧合酶2蛋白表达。结果:纳入动物32只,均进入结果分析。①4组血清总胆固醇水平比较:模型组、BQ-123组及辛伐他汀组高于基础组(P均<0.01)。BQ-123组及辛伐他汀组低于模型组(P均<0.05)。②4组血清三酰甘油水平比较:模型组、BQ-123组及辛伐他汀组高于基础组(P均<0.01)。BQ-123组及辛伐他汀组低于模型组(P均<0.01)。辛伐他汀组高于BQ-123组(P<0.01)。③4组血清低密度脂蛋白胆固醇水平比较:模型组、BQ-123组及辛伐他汀组高于基础组(P均<0.01)。辛伐他汀组低于模型组(P<0.05)。④4组血清高密度脂蛋白胆固醇水平比较:模型组、BQ-123组及辛伐他汀组低于基础组(P均<0.01)。BQ-123组高于模型组(P<0.01)。⑤BQ-123组及辛伐他汀组家兔动脉粥样硬化斑块内皮素1、巨噬细胞源泡沫细胞、环氧合酶2蛋白阳性表达均较模型组明显降低,BQ-123组家兔动脉粥样硬化斑块内皮素1、巨噬细胞源泡沫细胞、环氧合酶2蛋白阳性表达又较辛伐他汀组进一步降低。结论:内皮素1激活的内皮素A受体可以导致家兔动脉粥样硬化斑块环氧合酶2表达的上调;选择性内皮素A受体拮抗剂可以预防家兔动脉粥样硬化进程的发展。  相似文献   
37.
目的:在前期微囊化基因工程细胞制备平台的基础上,构建分泌型人肿瘤坏死因子α的真核表达载体PSNAV2.0-TNFα重组质粒,并鉴定其蛋白的体外瞬时表达,为进一步利用该基因进行微囊化细胞移植治疗和改善疾病奠定基础。方法:实验于2006-06/2007-05在解放军总医院老年医学研究所细胞生物学实验室完成。①以含有人肿瘤坏死因子αcDNA序列的质粒为模板,通过PCR扩增获得人肿瘤坏死因子α基因片段;将其定向插入真核表达载体PSNAV2.0中,获得重组质粒PSNAV2.0-TNFα。采用SalⅠ和EcoRⅠ双酶切法、PCR法及插入片段序列测定法鉴定该质粒。②利用阳离子脂质体介导法,将其转染到人胚胎肾细胞HEK-293细胞中,构建可持续分泌人肿瘤坏死因子α的基因工程细胞,采用RT-PCR法和Western blot法检测转染细胞培养上清液中人肿瘤坏死因子蛋白的体外瞬时表达。结果:①通过SalⅠ和EcoRⅠ双酶切、PCR及测序鉴定证明:在HEK-293中插入片段正确。②采用RT-PCR和Western blot法检测表明HEK-293细胞培养上清中有人肿瘤坏死因子α蛋白,Mr17000。结论:成功构建了重组质粒PSNAV2.0-TNFα真核表达载体,转染HEK-293细胞后可有效分泌人肿瘤坏死因子α蛋白,并能分泌到细胞外。  相似文献   
38.
目的:血液透析患者大多存在卡尼汀尤其是游离卡尼汀的缺乏,透析后补充左旋卡尼汀能够减轻、减少并发症及住院率。观察静脉补充左旋卡尼汀对肾移植前血液透析患者生活质量的影响。方法:选择2005-09/2006-09于柳州市人民医院进行维持性血液透析的患者30例,对治疗方案均知情同意。按随机数字表法分为左旋卡尼汀组和对照组,每组15例。每次透析结束后,左旋卡尼汀组静脉注射左旋卡尼汀20mg/kg,对照组注射等量的生理盐水,用药8周。用药前及用药8周时分别应用SF-36量表进行生活质量评分,由8个方面组成,每项都以0 ̄100分计,得分越高表示生活质量越好;同时记录透析相关症状及实验室参数,比较两组间差异。结果:30例患者全部进入结果分析。①与用药前相比,用药8周后左旋卡尼汀组SF-36总体评分增加了(18.29±12.71)分,对照组总评分减少了(6.40±16.39)分。与对照组相比,左旋卡尼汀组总评分及生理功能、总体健康、活力、社会功能、精神健康评分均显著增加(P<0.05 ̄0.01)。②与对照组相比,左旋卡尼汀组血红蛋白、白蛋白含量均显著增加(P<0.01)。结论:静脉补充左旋卡尼汀不仅有助于改善维持性血液透析患者的贫血状况,而且能明显提高其生活质量。  相似文献   
39.
Dubin-Johnson综合征是一种先天性非溶血性黄疸,在临床中较罕见,需与其他原因所导致的黄疸相鉴别.本文报告了我院1例Dubin- Johnson综合征的诊治情况,有助于加深对该病的认识.  相似文献   
40.
Chromodomain, helicase, DNA binding 5 (CHD5) is a member of a subclass of the chromatin remodeling Swi/Snf proteins and has recently been proposed as a tumor suppressor in a diverse range of human cancers. We analyzed all 41 coding exons of CHD5 for somatic mutations in 123 primary ovarian cancers as well as 60 primary breast cancers using high-resolution melt analysis. We also examined methylation of the CHD5 promoter in 48 ovarian cancer samples by methylation-specific single-stranded conformation polymorphism and bisulfite sequencing. In contrast to previous studies, no mutations were identified in the breast cancers, but somatic heterozygous missense mutations were identified in 3 of 123 ovarian cancers. We identified promoter methylation in 3 of 45 samples with normal CHD5 and in 2 of 3 samples with CHD5 mutation, suggesting these tumors may have biallelic inactivation of CHD5. Hemizygous copy number loss at CHD5 occurred in 6 of 85 samples as assessed by single nucleotide polymorphism array. Tumors with CHD5 mutation or methylation were more likely to have mutation of KRAS or BRAF (P = .04). The aggregate frequency of CHD5 haploinsufficiency or inactivation is 16.2% in ovarian cancer. Thus, CHD5 may play a role as a tumor suppressor gene in ovarian cancer; however, it is likely that there is another target of the frequent copy number neutral loss of heterozygosity observed at 1p36.  相似文献   
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