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91.
目的采用人工接种羊源细粒棘球绦虫原头蚴感染法建立小鼠与兔包虫病动物模型。方法 6周龄昆明小鼠经皮穿刺腹腔内接种羊源细粒棘球绦虫原头蚴悬液,新西兰大白兔于腹部手术后肝脏接种羊源细粒棘球绦虫原头蚴悬液。接种原头蚴6个月后剖检动物,观察小鼠腹腔和新西兰大白兔肝脏内包虫囊生长情况。结果接种羊源细粒棘球绦虫原头蚴6个月后,小鼠腹腔内包囊生成率为95%,新西兰大白兔肝内包囊生成率为50%。光镜观察见在小鼠腹腔和兔肝脏形成的囊泡具有与羊肝脏棘球蚴囊壁类似的类上皮细胞层和板层状结构。3种动物体内棘球蚴均有原头蚴。结论以羊源细粒棘球绦虫原头蚴悬液接种昆明小鼠腹腔和新西兰大白兔肝脏,可以建立小鼠和兔包虫病动物模型。  相似文献   
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Lan J  Gao Z  Xiong H  Chuai X  Jin Y  Li J  Xian X  Liu G  Xie L  Zhang Y  Wang Y 《Vaccine》2011,29(40):6894-6902
Coxsackievirus B3 (CVB3) causes viral myocarditis and can ultimately result in dilated cardiomyopathy. However, there is no vaccine available for clinical use. In this study, we assessed the protection provided by three immunization strategies against CVB3 infection. Vaccination was performed with a DNA vaccine expressing the cloned capsid gene VP1 or a vaccine developed from purified VP1 protein. Third, a strategy of vaccination was attempted with the DNA vaccine followed by two boosts with the recombinant protein vaccine (DNA prime-protein boost vaccine). Followed immunization, mice were challenged with CVB3 infection. Improved induction of CVB3-specific antibodies and neutralizing antibodies were found in mice immunized by the DNA prime-protein boost regimen. Furthermore, virus-specific cytotoxic activity of spleen cells derived from DNA prime-protein boost vaccinated mice was elicited. In addition, the DNA prime-protein boost vaccine resulted in protection of 75% of mice from lethal CVB3 challenge and a significant reduction of viral load in sera of immunized mice after acute CVB3 infection. There was a significant reduction in myonecrosis and infiltrating myocardial immune cells indicating reduced severity of myocarditis in surviving mice. These findings demonstrated that a DNA prime-protein boost immunization strategy, but not a DNA vaccine or protein vaccine alone, was effective in eliciting both humoral and cell-mediated immune responses against CVB3 infection in mice and might be a promising vaccine candidate.  相似文献   
94.
目的 进行不同品系白纹伊蚊转铁蛋白基因表达量的分析.方法 据二维电泳获得肽段序列设计引物扩增基因片段,荧光定量PCR检测在白纹伊蚊抗性品系、敏感品系、现场采集品系蚊体内的表达水平差异.结果 成功扩增白纹伊蚊转铁蛋白基因片段,荧光定量PCR表明转铁蛋白基因在抗性品系蚊体内的表达量是敏感品系的10.51倍,现场品系是敏感品...  相似文献   
95.
一流的研究生教育是“双一流”建设的重要基础。从健全导师责权机制、深化课程体系改革、强化共享平台建设、完善培养质量评价机制等方面,探讨我校在“双一流”建设中研究生教育改革与创新的具体举措,展示了研究生培养模式改革的初步成效,为地方高校推进“双一流”建设提供有益借鉴。  相似文献   
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97.
《Ticks and Tick》2022,13(6):102034
Tick infestation and pathogen prevalence in ticks infesting the Saharan antelope addax (Addax nasomaculatus) are factors that may constitute a risk for both human and animal health. In this study we describe season distribution of adult Hyalomma marginatum and analyzed the tick-borne pathogens and their seroprevalence in natural-living addax in Morocco. The results showed that addax is an important host species for H. marginatum adults. The seroprevalence of Bluetongue virus (BTV; 61.5–92.3%, n = 8/13-84/91), Coxiella burnetii (36.3–69.2%, n = 33/91-9/13) and Brucella spp. (0.0–4.8%, n = 0/50-2/42) was characterized in addax during various years (sampled animals per year, n = 13–91). Presence of Aigai virus (AIGV), a recent taxonomic differentiation of Crimean-Congo hemorrhagic fever virus (CCHFV) of 100% (4/4, years 2016 and 2017) together with Babesia ovis (75%, 3/4, year 2014), Anaplasma spp. (75%, 3/4, year 2014), Rickettsia spp. (50%, 2/4, year 2014) and Theileria spp. (25%, 1/4, year 2014) was observed in H. marginatum collected from the addax (4 pools of 10 adult ticks each). The results support the role of addax host in H. marginatum life cycle and exposure to AIGV and other tick-borne pathogens. The development of control interventions including anti-tick vaccines for wildlife species will contribute to the implementation of effective measures for the prevention and control of tick-borne diseases and might be relevant for the preservation of this threatened species and others such as Arabian oryx (Oryx leucoryx) and African elk (Taurotragus oryx) that share habitat.  相似文献   
98.
《Vaccine》2016,34(11):1370-1378
Tuberculosis (TB) is a serious disease around the world, and protein based subunit vaccine is supposed to be a kind of promising novel vaccine against it. However, there is no effective adjuvant available in clinic to activate cell-mediated immune responses which is required for TB subunit vaccine. Therefore, it is imperative to develop new adjuvant. Here we reported an adjuvant composed of dimethyl dioctadecylammonium (DDA), Poly I:C and cholesterol (DPC for short). DDA can form a kind of cationic liposome with the ability to deliver and present antigen and can induce Th1 type cell-mediated immune response. Poly I:C, a ligand of TLR3 receptor, could attenuate the pathologic reaction induced by following Mycobacterium tuberculosis challenge. Cholesterol, which could enhance rigidity of lipid bilayer, is added to DDA and Poly I:C to improve the stability of the adjuvant. The particle size and Zeta-potential of DPC were analyzed in vitro. Furthermore, DPC was mixed with a TB fusion protein ESAT6-Ag85B-MPT64(190-198)-Mtb8.4-Rv2626c (LT70) to construct a subunit vaccine. The subunit vaccine-induced immune responses and protective efficacy against M. tuberculosis H37Rv infection in C57BL/6 mice were investigated. The results showed that the DPC adjuvant with particle size of 400 nm and zeta potential of 40 mV was in good stability. LT70 in the adjuvant of DPC generated strong antigen-specific humoral and cell-mediated immunity, and induced long-term higher protective efficacy against M. tuberculosis infection (5.41 ± 0.38 log10 CFU) than traditional vaccine Bacillus Calmette–Guerin (BCG) (6.01 ± 0.33 log10 CFU) and PBS control (6.53 ± 0.26 log10 CFU) at 30 weeks post-vaccination. In conclusion, DPC would be a promising vaccine adjuvant with the ability to stimulate Th1 type cell-mediated immunity, and could be used in TB subunit vaccine.  相似文献   
99.
BackgroundHepatocellular carcinoma (HCC) is a frequent diagnosed malignancy. microRNAs (miRs) are involved in various cellular processes during cancer development. This study attempted to probe the miR-based mechanism in hepatitis B virus X protein (HBx) small interfering RNA (siRNA)-treated HCC cells.MethodsHBx expression in hepatocyte and HCC cells was detected, and cells with highest HBx expression were screened out and transfected with HBx-siRNAs. Then the effect of HBx on HCC cell proliferation was detected. miRs differentially expressed in HBx-siRNA-transfected MHCC97H cells were analyzed and verified. miR-137 methylation was analyzed by bioinformatics, and miR-137 restoration was detected after Aza treatment. Furthermore, miR-137 methylation in MHCC97H cells with HBx knockdown or HBx overexpression was detected by methylation specific PCR. The targeting relationship between miR-137 and Notch1 was verified. Then the gain-and-loss functions of miR-137 or/and Notch1 were performed to estimate their roles in HCC cell proliferation. The effects of HBx-siRNA and overexpressed miR-137 in vivo were observed by tumor xenograft in nude mice and immunohistochemistry.ResultsHBx-siRNA weakened MHCC97H cell proliferation and tumor growth. miR-137 was highly expressed in HBx-siRNA-treated HCC cells and targeted Notch1. HBx knockdown decreased miR-137 methylation and restored miR-137 expression. miR-137 overexpression prevented HCC cell proliferation and tumor growth, while miR-137 downregulation reversed the repressing effects of HBx-siRNA on HCC cell proliferation. Inhibition of Notch1 reversed HCC cell proliferation induced by miR-137 downregulation.ConclusionOverexpression of miR-137 blocks HCC cell proliferation in HBx-siRNA-treated MHCC97H cells by targeting Notch1. This study may offer novel target for HCC treatment.  相似文献   
100.
AIM:to study the prevalence of human papillomavirus(HPV) in esophageal carcinoma in tangshan,China,a high-incidence area.METHODS:Formalin-fixed,paraffin-embedded tissue specimens from 198 patients who were pathologically diagnosed with esophageal squamous cell carcinoma from 2011 to 2013 were obtained from a pathology department in Tangshan.DNA was extracted from all198 specimens to detect HPV by polymerase chain reaction(PCR).β-globin PCR was performed to check the quality of the DNA extraction procedure.PCR was performed to detect a wide range of HPV types,and type-specific PCR was performed to detect HPV types16 and 18.Negative and positive controls were used for HPV 16 and 18 detection.RESULTS:the DNA extraction method in this study appeared to be more effective than other previously reported methods.After DNA extraction,more than98%of the tissue specimens had an acceptable result in the DNA qualification test(β-globin PCR).the overall prevalence of HPV in tumor tissues by GP6+/GP5+PCR was 79.79%,and the prevalence of HPV types16 and 18 was 40.40%and 47.47%,respectively.PCR demonstrated the presence of HPV,and direct sequencing confirmed the HPV genotypes.All HPVpositive PCR products were checked by DNA sequence analysis using DNAman and compared with the known HPV sequences listed in the basic Local Alignment Search tool database to evaluate the HPV types.this analysis confirmed the presence of HPV types 16 and18.CONCLUSION:DNA of high-risk HPV types 16 and 18is present in esophageal tumors,implicating HPV as a possible etiologic factor for esophageal squamous cell carcinoma.  相似文献   
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