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61.
In thorium molten salt reactors (TMSR), 233Pa is an important intermediate nuclide in the conversion chain of 232Th to 233U, its timely separation from the fuel salt is critically important for both the thorium–uranium (Th–U) fuel cycle and the neutron economy of the reactor. In this study, the evaporation behavior of 233Pa in the FLiBeZr molten salt was investigated during a vacuum distillation process. The separation characteristics between 233Pa and the major components of the fuel (salt and fission products) were evaluated in a calculation of the separation factors between these components. It was found that 233Pa5+ evaporated more readily than 233Pa4+ and the other components of the fuel, the relatively low temperature and medium pressure were much more beneficial to the separation of 233Pa5+ from FLiBeZr salt in the evaporation process, with the maximum value of the separation factor achieving more than 102. Results of distillation experiments also show that increasing the temperature and decreasing the ambient pressure enhances the separation between 233Pa5+ and most of the fission product nuclides due to the 233Pa5+ volatility more strongly depending on the process conditions. These results will be utilized to design a concept for a process for 233Pa separation from the fuel of a molten salt reactor.

The evaporation behavior of 233Pa in the FLiBeZr molten salt was investigated during a vacuum distillation process.  相似文献   
62.
Titanium for additive manufacturing presents a challenge in the control of costs in the fabrication of products with expanding applications compared with cast titanium. In this study, hydrogenated–dehydrogenated (HDH) titanium powder with a low cost was employed to produce spherical Ti powder using the radiofrequency plasma (RF) technique. The spherical Ti powder was used as the raw material for laser directed energy deposition (LDED) to produce commercially pure titanium (CP-Ti). Microstructural analyses of the powder revealed that RF treatment, not only optimized the shape of the titanium powder, but also benefited in the removal of the residual hydride phase of the powder. Furthermore, the LDED-HDH-RF-produced samples showed an excellent combination of tensile strength and tensile ductility compared to the cast and the LDED-HDH-produced samples. Such an enhancement in the mechanical properties was attributed to the refinement of the α grain size and the dense microstructure. The present work provides an approach for LDED-produced CP-Ti to address the economic and mechanical properties of the materials, while also providing insights into the expanding application of HDH titanium powder.  相似文献   
63.
64.
Ultrasound myocardial cavitation-enabled treatment was applied to the SS-16BN rat model of hypertrophic cardiomyopathy for proof of the principle underlying myocardial reduction therapy. A focused ultrasound transducer was targeted using 10-MHz imaging (10 S, GE Vivid 7) to the left ventricular wall of anesthetized rats in a warmed water bath. Pulse bursts of 4-MPa peak rarefactional pressure amplitude were intermittently triggered 1:8 heartbeats during a 10-min infusion of a microbubble suspension. Methylprednisolone was given to reduce initial inflammation, and Losartan was given to reduce fibrosis in the healing tissue. At 28 d post therapy, myocardial cavitation-enabled treatment significantly reduced the targeted wall thickness by 16.2% (p?<0.01) relative to shams, with myocardial strain rate and endocardial displacement reduced by 34% and 29%, respectively, which are sufficient for therapeutic treatment. Premature electrocardiogram complexes and plasma troponin measurements were found to identify optimal and suboptimal treatment cohorts and would aid in achieving the desired impact. With clinical translation, myocardial cavitation-enabled treatment should fill the need for a new non-invasive hypertrophic cardiomyopathy therapy option.  相似文献   
65.
Flexible electric-double-layer (EDL) thin film transistors (TFTs) based on a vertical InGaZnO4 (IGZO) channel are fabricated at room temperature. Such TFTs show a low operation voltage of 1.0 V due to the large specific gate capacitance of 3.8 μF cm−2 related to electric-double-layer formation. The threshold voltage, drain current on/off ratio and subthreshold swing are estimated to be −0.1 V, 1.2 × 106 and 80 mV per decade, respectively. The combination of low voltage, high current on-to-off ratio and room temperature processing make the flexible vertical-IGZO-channel TFTs very promising for low-power portable flexible electronics applications.

Flexible electric-double-layer (EDL) thin film transistors (TFTs) based on a vertical InGaZnO4 (IGZO) channel are fabricated at room temperature.  相似文献   
66.
67.
目的用基因表达分析法鉴定丙型肝炎病毒(HCV)核心(Core,C)区基因插入突变体编码蛋白在人肝癌细胞系(Huh-7)表达,探讨该蛋白生物学功能及其基因表达改变与致病的关系。方法构建HCV-1bc基因插入突变体编码蛋白重组表达质粒,建立表达c基因插入突变体编码蛋白Huh-7细胞系,按Affymetrix公司实验程序制备探针、再与该公司H0u133A和Hg-u133b芯片杂交。对基因表达上调或下调≥3倍的基因,用NetAflk作进一步分析。并用半定量RT-PCR对其中3个上调基因进行鉴定。结果Microarray分析显示,HCV-1b C基因插入突变体编码蛋白比c蛋白引起更多的基因表达改变,主要集中在信号传导、蛋白酶活性、分子转运、免疫反应等,特别是免疫反应基因表达更加显著。C基因插入突变体编码蛋白表达可同时导致凋亡基因/抗凋亡基因表达上调或下调及致癌基因上调。半定量RT-PCR对有趣的致癌基因FHL2、抗凋亡基因PRKCZ和凋亡基因LGALSI的鉴定结果表明,FHL2、PRKCZ和LGALSI基因的表达比空载体转染对照组相同基因明显上调。结论Hcvc基因插入突变体编码蛋白在Huh-7细胞表达对其基因表达有很大影响,其中对免疫反应基因的影响更明显,这一结果对理解HCV C基因插入突变体编码蛋白在HCV致病过程中的作用及其研制抗HCV药物均有重大的参考价值。  相似文献   
68.
目的 :检测胆囊癌组织中P6 2蛋白、碱性成纤维细胞生长因子(bFGF)的表达和微血管密度 (MVD) ,探讨它们的相互关系 ,以及与胆囊癌临床病理特征的关系。方法 :4 1例胆囊癌和 2 2例慢性胆囊炎组织中 ,P6 2蛋白和bFGF的表达用SP免疫组化染色法进行检测。胆囊癌组织中MVD用抗CD34单抗 (mAb)做SP免疫组化染色进行检测。结果 :4 1例胆囊癌组织中 ,P6 2和bFGF表达阳性率分别为 6 3.4 %和 75 .6 % ,均高于 2 2例慢性胆囊炎组织 (P <0 .0 1)。P6 2的表达与胆囊癌淋巴结转移有关 (P <0 .0 5 ) ,与癌组织的分级、临床分期无显著关系。bFGF的表达与胆囊癌临床病理分期及组织学分级有关 (P <0 .0 5 ) ,而与淋巴结转移无显著关系。P6 2表达率与bFGF表达率呈正相关关系 (r=0 .5 2 1;P <0 .0 1)。两者的表达均与患者的年龄、性别、肿瘤的种类、是否伴有胆囊结石无关。胆囊癌组织中MVD明显高于慢性胆囊炎组织 (P <0 .0 1)。P6 2及bFGF表达阳性组织MVD高于表达阴性组织 (分别P <0 .0 5和P <0 .0 1)。MVD与胆囊癌的Nevin分期及淋巴结转移有关 (P<0 .0 1) ,与患者的年龄、性别、肿瘤种类、分化程度以及是否伴有胆囊结石无关。结论 :P6 2蛋白及bFGF的表达与胆囊癌组织中血管的生成相关 ,在胆囊癌的发生和发展过程中可能具有重  相似文献   
69.
To investigate the biological and immunological characteristics of the Nanjing local strains of HHV-7,fourstrains of herpesvirus were isolated from saliva specimens of one healthy individual and three childrensuffering from a kidney disease in Nanjing.The viruses were identified by transmission electron microscopy(EM),indirect immunofluorescence assay(IFA) with a specific monoclonal antibody;nested polymerase chainreaction,restriction mapping and DNA sequencing.The virus-infected cells showed the typical cytophathiceffect(CPE) under microscopy and could be detected by IFA with the human herpesvirus-7(HHV-7) specificantibody.Under EM,herpesvirus-like and virions capsids could be found in their cytoplasm or nucleoplasm.HHV-7 DNA fragments amplified from infected cells by nested PCR were confirmed by restriction mappingand DNA sequencing.Similarly to DC strain,an known HHV-7 strain used in the present study as the positivecontrol,the virus could be inactivated by ultraviolet irradiation for 10 min,heated at 45℃ for 30 min,pH<5or>9 at 4℃ for 2 h and ether or chloroform for 10 h.The virus induced the production of TNF-α,IL-10 andIL-12p70 while inhibited IFN-γ secretion,increased the percentage of CD2~+ cells while decreased that of CD4~+or CD45RA~+ cells.The results indicate that the viruses isolated in Nanjing are HHV-7,which has similarbiological characteristic to the known HHV-7 strain,DC.Infection with HHV-7 in vitro could affect immunefunction of lymphocytes by disturbing cytokine production and CD antigen expression.Cellular & MolecularImmunology.2004;1(5):367-372.  相似文献   
70.
He L  Tang X  Li N  Wu YQ  Wang JW  Li JR  Zhang ZX  Dou HD  Liu JJ  Yu LP  Xu HT  Zhang JG  Hu YH 《Maturitas》2012,72(2):132-138

Objectives

This study was to explore the independent influence of menopause on cardiovascular disease (CVD) and its risk factors in rural Chinese females.

Study design

This cross-sectional population-based study enrolled 2245 premenopausal and 2498 postmenopausal women aged 40–59 years in Fangshan district, Beijing, China. Data was collected by face-to-face interview, physical examination and biochemical examination during 2009 and 2010. General liner models were employed to calculate age-adjusted means of cardiovascular risk factors (CRFs). The comparisons of CVD and it risk factors according to menopausal status, and calculation of adjusted odds ratios/coefficients and their 95% confidence intervals for the associations of quartiles of elapsed time since menopause and age at menopause with CVD and its risk factors was performed by multivariate logistic/liner regression models separately.

Results

After adjustment for age and other confounders, no statistically significant association of menopause with CVD was observed in our participants; however, dyslipidemia prevalence and levels of waist-to-hip ratio, triglycerides, total cholesterol and low-density lipoprotein cholesterol were presented higher in postmenopausal group, compared to the premenopausal one (P < 0.05). Compared to women who had been menopausal for less than1 year, those with the elapsed time since menopause of 2–3 years had higher CHD prevalence, higher triglycerides level and lower high-density lipoprotein cholesterol level (P < 0.05).

Conclusions

Postmenopausal women in rural China had worse CRFs profile than the premenopausal ones, which implied menopause might aggravate the CRFs epidemic beyond effects of aging, and would increase the CVD burden during and after their middle ages.  相似文献   
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