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11.
目的 观察SARS患者血清干扰素-2α(IFN--2α)含量变化。方法用放射免疫法检测了66例SARS患者血清IFN-2α含量,并与正常对照组作比较。结果SARS组进展期患者IFN-2α含量明显高于对照组,重型SARS患者血清IFN-2α含量要么较高,要么较低。结论患者血清IFN-2α含量变化提示细胞免疫参与了机体的免疫反应,重症SARS患者IFN-2α含量变化反映了患者的免疫机能状况差异。  相似文献   
12.
目的 应用膜反向斑点杂交技术快速检测结核分枝杆菌对链霉素(SM)的耐药性。方法 设计与合成用于检测结核分枝杆菌耐SM基因rpsL和ms的寡核苷酸探针,点于硝酸纤维素膜上,与结核分枝杆菌分离株生物素标记的聚合酶链反应(PCR)产物进行反向斑点杂交,并与PCR-单链构象多态性(PCR—SSCP)和PCR-直接测序(PCR-DS)结果比较。结果 53株结核分枝杆菌临床分离株中,三种检测方法符合率为100%。9株敏感株rpsL和ms基因的SSCP图谱、膜杂交结果与标准株完全相同;44株耐SM菌株中,33株存在rpsL基因43位密码子AAG→AGG突变,6株有ms基因513位A→C突变,1株有ms基因513住A→T突变,突变检出率为90.9%,40株耐SM菌株和9株敏感株可用膜杂交方法检测出来,与传统药敏试验方法检测符合率为49/53。结论 应用膜反向斑点杂交技术检测结核分枝杆菌耐SM基因型灵敏度高、特异性好、简便、快速,可用于临床耐药性检测。  相似文献   
13.
钛镍记忆合金牵张器牵张增高牙槽嵴的动态研究   总被引:2,自引:0,他引:2  
目的:通过对犬牵张手术后的下颌牙槽嵴高度、骨密度和组织学变化进行动态研究,了解应用钛镍记忆合金牵张器牵张成骨增高牙槽嵴的变化规律。方法:牵张增高牙槽嵴的15只犬于术前、术后1周、5周、3个月、6个月分别测量术区及对照侧相应位置颌骨高度,拍X线片,取牵张区及对照侧相同区域骨块进行双能X线骨密度测量并进行组织学研究。结果:牙槽嵴增高高度在牵张术后1、3、6个月分别减少5%、8%、11%。牵张术后3个月,牵张区骨密度低于对照侧;6个月,与对照侧的差异无显著性。结论:使用TiN i-SMA牵张器增高牙槽嵴成骨迅速,再吸收程度较低,成骨形态满意。牵张成的新骨有足够的强度,可以满足种植等后期修复的要求。  相似文献   
14.
目的:观察同基因骨髓单个核细胞经冠状动脉植入心脏后的分布及分化状况。方法:用雄性近交系Lew is大鼠作为模型动物。首先,在大鼠颈部异位心脏移植模型基础上,以冷冻法制备急性心肌梗死模型。其次,心肌梗死模型建立2 d后,分离、纯化大鼠骨髓单个核细胞,并以PKH26红色荧光染料标记。然后,经移植心脏冠状动脉输注PKH26标记的同基因骨髓单个核细胞(实验组)和DMEM培养液(对照组)。最后,细胞移植7 d后,采集各标本,检测植入细胞分布及分化状况。结果:病理检查证实冷冻区域心肌变性坏死且界线清楚。利用该模型成功的模拟了临床经冠状动脉输注自体骨髓单个核细胞的治疗方法。PKH26红色荧光阳性细胞主要集中于实验组大鼠移植心脏的冷冻梗死区,脾脏、骨髓也可见少量阳性细胞分布,移植心脏的非梗死区及其余脏器组织切片均未见红色荧光阳性细胞;梗死区内PKH26标记的细胞部分表达CD34;梗死区内connexin43的表达明显高于对照组。结论:供者同基因骨髓单个核细胞经冠状动脉移植后,能够存活并定向迁移至心肌损伤区域,并且可能促使梗死区出现心肌再生。  相似文献   
15.
采用特尔斐法制定医学硕士公共课程教学质量评价体系,组织军医进修学院2005年级硕士生进行评价。除政治与计算机应用之间、计算机应用与医学统计学之间、医学统计学与英语之间的评价得分差异无统计学意义外,其它各科目之间的评价得分差异均有统计学意义;课程满意率与课程评价得分呈线性相关。结果显示,采用医学硕士公共课程教学质量评价体系能够对教学质量进行有效评价,对今后教学工作的改进和教学质量的不断提高具有指导作用。  相似文献   
16.
PurposeThe aim of this study is to investigate the anti-inflammatory effect of Radix Hedysari Polysaccharide (HPS) on clinical indicators, the expression of Toll-like receptor-4 (TLR4) and its downstream transduction molecules during endotoxin-induced uveitis in rats.MethodsEIU was induced through the intraperitoneal injection of male Wistar rats with lipopolysaccharide (LPS 200 μg). HPS (400 mg/kg), DXM (1 mg/kg) or an equivalent volume of normal saline was injected intraperitoneally 1 h before the LPS induction. The clinical manifestation was observed and scored at 2-h intervals using a slit microscope. The degree of inflammatory reaction was determined by routine histological examinations, and the expression of TLR4 and MyD88 in the iris-ciliary body complex was detected through a double-labeled immunofluorescence study. Real-time RT-PCR was used to assess the effects of HPS on the expression of the TLR4 complex, MyD88 and NF-κB p65 mRNA. The protein expression levels of TLR4, MyD88 and NF-κB p65 were examined by western blot.ResultsHPS treatment produced similar therapeutic results with dexamethasone by significantly reducing the clinical severity of EIU as well as fibrin exudations and inflammatory cell infiltration in the eye. Correspondingly, according to the immunofluorescence results, HPS treatment significantly suppressed the expression of TLR4 and MyD88 in the iris–ciliary body complex. HPS treatment could also remarkably reduce the mRNA and protein expression of the TLR4 complex, MyD88 and NF-κB p65.ConclusionHPS can suppress the intraocular inflammation observed in EIU by inhibiting TLR4 and its downstream signal transduction pathway.  相似文献   
17.
《Acta biomaterialia》2014,10(6):2630-2642
There is still unmet demand for developing powerful approaches to produce polymeric nanoplatforms with versatile functions and broad applications, which are essential for the successful bench-to-bedside translation of polymeric nanotherapeutics developed in the laboratory. We have discovered a facile, convenient, cost-effective and easily scalable one-pot strategy to assemble various lipophilic therapeutics bearing carboxyl groups into nanomedicines, through which highly effective cargo loading and nanoparticle formation can be achieved simultaneously. Besides dramatically improving water solubility, the assembled nanopharmaceuticals showed significantly higher bioavailability and much better therapeutic activity. These one-pot assemblies may also serve as nanocontainers to effectively accommodate other highly hydrophobic drugs such as paclitaxel (PTX). PTX nanomedicines thus formulated display strikingly enhanced in vitro antitumor activity and can reverse the multidrug resistance of tumor cells to PTX therapy. The special surface chemistry offers these assembled entities the additional capability of efficiently packaging and efficaciously transfecting plasmid DNA, with a transfection efficiency markedly higher than that of commonly used positive controls. Consequently, this one-pot assembly approach provides a facile route to multifunctional nanoplatforms for simultaneous delivery of multiple therapeutics with improved therapeutic significance.  相似文献   
18.
熊志红  李仁德  朱琰 《实用癌症杂志》2011,26(6):558-560,564
目的构建smad2特异性小干扰RNA(siRNA)真核表达载体,并检测肿瘤细胞中其对smad2基因表达的干扰效果。方法根据smad2基因序列设计合理的smad2 siRNA,并将合成的寡核苷酸序列克隆到pSliencer 2.1-U6 neo载体中,转化大肠杆菌DH5α;挑取阳性菌落进行质粒酶切和序列分析;将构建正确的smad2 siRNA重组质粒转染,或与带Flag标签的smads真核表达载体共同转染293T细胞或HeLa细胞,收集细胞裂解物,Westem印迹检测siRNA的干扰效果。结果正确构建了smad2 siRNA重组质粒,对smad2表达的特异性干扰效果可达70%以上。结论成功构建了smad2 siRNA载体,为进一步探讨smad2在肿瘤发生发展中的作用奠定了基础。  相似文献   
19.
目的 观察和评价SARS患者血清甲状腺素和甲状旁腺素含量变化。方法 用电化学发光法检测了 48例SARS患者血清甲状腺素、甲状旁腺素和促甲状腺激素含量,并与正常对照组作了比较。结果 患者T3、T4 、FT3和TSH含量明显低于对照组,重型SARS患者血清T3含量明显低于普通型。甲状旁腺素水平 2组间无显著性差异。结论 血清甲状腺素和促甲状腺激素含量变化可能是SARS病程中的一个重要表现。  相似文献   
20.
《Vaccine》2015,33(30):3592-3599
BackgroundNew, more effective vaccines to prevent tuberculosis (TB) disease are needed urgently. H4:IC31 is an investigational vaccine that contains a fusion protein of the immunodominant antigens TB10.4 and Ag85B, formulated in IC31® adjuvant. We assessed the safety and immunogenicity of H4:IC31 in South African adults from a TB endemic setting.MethodsIn this double blind, placebo controlled, phase I trial, Mycobacterium tuberculosis-uninfected, HIV-uninfected, healthy adults with a history of childhood BCG vaccination were randomly allocated to two intramuscular vaccinations with 5, 15, 50 or 150 μg H4 formulated in 500 nmol IC31®, two months apart. Vaccinees were followed for six months to assess safety; immunogenicity was measured by ELISpot and intracellular cytokine staining assays.ResultsThirty-two participants received H4:IC31 and 8 received placebo. Injection site adverse events were common but mild; mild fatigue was the most common systemic adverse event. Frequencies of adverse events did not differ between dosage groups. Detectable antigen-specific CD4 T cell responses were induced by all doses of H4:IC31, but doses below 50 μg induced the highest frequencies of CD4 T cells, comprised predominantly of IFN-γ+TNF-α+IL-2+ or TNF-α+IL-2+ cells. These memory responses persisted up to the end of follow up, on study day 182.ConclusionsH4:IC31 demonstrated an acceptable safety profile and was immunogenic in South African adults. In this trial, the 15 μg dose appeared to induce the most optimal immune response.  相似文献   
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