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The 5-year survival of hepatocellular carcinoma (HCC) is difficult due to the high recurrence rate and metastasis. Tumor infiltrating immune cells (TICs) and immune-related genes (IRGs) bring hope to improve survival and treatment of HCC patients. However, there are problems in predicting immune signatures and identifying novel therapeutic targets. In the study, the CIBERSORT algorithm was used to evaluate 22 immune cell infiltration patterns in gene expression omnibus (GEO) and the cancer genome atlas (TCGA) data. Eight immune cells were found to have significant infiltration differences between the tumor and normal groups. The CD8+ T cells immune signature was constructed by least absolute shrinkage and selection operator (LASSO) algorithm. The high infiltration level of CD8+ T cells could significantly improve survival of patients. The weighted gene co-expression network analysis (WGCNA) algorithm identified MMP9 was closely related to the overall survival of HCC patients. K-M survival and tROC analysis confirmed that MMP9 had an excellent prognostic prediction. Cox regression showed that a dual immune signature of CD8+ T cells and MMP9 was independent survival factor in HCC. Therefore, a dual prognostic immune signature could improve the survival of patient and may provide a new strategy for the immunotherapy of HCC.  相似文献   
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To determine whether pre-hospitalization use of aspirin is associated with all-cause mortality in coronavirus disease 2019 (COVID-19) patients with coronary artery disease (CAD). We recruited 183 adult patients with CAD diagnosed with COVID-19, including 52 taking low-dose aspirin (mean [SD] age, 69.7 [1.1] years; 59.6% men) and 131 without using aspirin (mean [SD] age, 71.8 [0.9] years; 51.9% men), who were admitted in the Tongji hospital in Wuhan, China from January 10, 2020 to March 30, 2020. There was no difference on in-hospital mortality between aspirin group and non-aspirin group (21.2% vs. 22.1%, P = .885). Similarly, for critically severe COVID-19 patients, the mortality in aspirin group was close to that in non-aspirin group (44% vs. 45.9%, P = .872). Moreover, the percentage of patients with CAD taking low-dose aspirin did not differ between those survivors and non-survivors (28.7% vs. 27.5%, P = .885). Meanwhile, the usage of aspirin was not correlated with all-cause mortality in multivariate analysis (OR = 0.944, 95% CI: 0.411-2.172, P = .893). Collectively, our study suggested that the pre-hospitalization use of low-dose aspirin was not associated with the clinical outcome of patients with CAD hospitalized with COVID-19 infections.  相似文献   
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Background and aims

SOC inventory and soil δ13C were widely used to access the size of soil C pool and to indicate the dynamics of C input and output. The effects of climatic factors and soil physical characteristics and plant litter input on SOC inventory and soil δ13C were analyzed to better understand the dynamics of carbon cycling across ecosystems on the Qinghai-Tibetan Plateau.

Methods

Field investigation was carried out along the two transects with a total of 1,875 km in length and 200 km in width. Sixty-two soil profiles, distributed in forest, meadow, steppe, and cropland, were stratified sampled every 10 cm from 0 to 40 cm.

Results

Our result showed that SOC density in forest and meadows were much higher than in steppe and highland barley. In contrast, δ13C in forest and meadow were lower than in steppe and highland barley. Soil δ13C tended to enrich with increasing soil depth but SOC decline. SOC and δ13C (0–40 cm) were correlated with different climatic factors in different ecosystems, such that SOC correlated negatively with MAT in meadow and positively with MAP in steppe; δ13C correlated positively with MAT in meadow and steppe; and δ13C also tended to increase with increasing MAT in forest. Of the variation of SOC, 55.15 % was explained by MAP, pH and silt content and 4.63 % was explained by the interaction between MAT and pH across all the ecosystems except for the cropland. Meanwhile, SOC density explained 27.40 % of variation of soil δ13C.

Conclusions

It is suggested that different climatic factors controlled the size of the soil C pool in different ecosystems on the Tibetan Plateau. SOC density is a key contributor to the variation of soil δ13C.  相似文献   
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Objective

Vascular calcification is a common pathobiological process which occurs among the elder population and in patients with diabetes and chronic kidney disease. Osteoprotegerin, a secreted glycoprotein that regulates bone mass, has recently emerged as an important regulator of the development of vascular calcification. However, the mechanism is not fully understood. The purpose of this study is to explore novel signaling mechanisms of osteoprotegerin in the osteoblastic differentiation in rat aortic vascular smooth muscle cells (VSMCs).

Methods and Results

VSMCs were isolated from thoracic aorta of Sprague Dawley rats. Osteoblastic differentiation of VSMCs was induced by an osteogenic medium. We confirmed by Von Kossa staining and direct cellular calcium measurement that mineralization was significantly increased in VSMCs cultured in osteogenic medium; consistent with an enhanced alkaline phosphatase activity. This osteoblastic differentiation in VSMCs was significantly reduced by the addition of osteoprotegerin in a dose responsive manner. Moreover, we identified, by real-time qPCR and western blotting, that expression of Notch1 and RBP-Jκ were significantly up-regulated in VSMCs cultured in osteogenic medium at both the mRNA and protein levels, these effects were dose-dependently abolished by the treatment of osteoprotegerin. Furthermore, we identified that Msx2, a downstream target of the Notch1/RBP-Jκ signaling, was markedly down-regulated by the treatment of osteoprotegerin.

Conclusion

Osteoprotegerin inhibits vascular calcification through the down regulation of the Notch1-RBP-Jκ signaling pathway.  相似文献   
46.
The biological role of installing a critical exocyclic enone into the structure of the alkaloid, (?)-eburnamonine, and characterization of the new chemical reactivity by quantitative NMR without using deuterated solvents are described. This selective modification to a natural product imparts potent anticancer activity as well as bestows chemical reactivity toward nucleophilic thiols, which was measured by quantitative NMR. The synthetic strategy provides an overall conversion of 40%. In the key synthetic step, a modified Peterson olefination was accomplished through the facile release of trifluoroacetate to create the requisite enone in the presence of substantial steric hindrance.  相似文献   
47.
Liu  Jiajun  Tang  Huaping  Qu  Xiangru  Liu  Hang  Li  Cong  Tu  Yang  Li  Shuiqing  Habib  Ahsan  Mu  Yang  Dai  Shoufeng  Deng  Mei  Jiang  Qiantao  Liu  Yaxi  Chen  Guoyue  Wang  Jirui  Chen  Guangdeng  Li  Wei  Jiang  Yunfeng  Wei  Yuming  Lan  Xiujin  Zheng  Youliang  Ma  Jian 《Plant molecular biology》2020,104(1-2):173-185
Plant Molecular Biology - A novel and major QTL for the effective tiller number was identified on chromosomal arm 1BL and validated in two genetic backgrounds The effective tiller number (ETN)...  相似文献   
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The capacitive performance of carbon materials could be enhanced by means of increasing the number of active sites, the surface area, and the porosity as well as through incorporating heteroatoms into the carbon framework. However, the charge storage through electric double‐layer mechanism results in limited increase in capacitance of modified carbon materials. Herein, a simple and straightforward strategy is introduced for in situ synthesizing iron complex (FeX, which X includes O, C, and P) nanoparticles encapsulated into biomass‐derived N, P‐codoped carbon nanotubes (NPCNTs), using a natural resource, egg yolk, as heteroatom‐enriched carbon sources and potassium ferricyanide as the precursor for iron complex. Compared with heteroatom‐enriched carbon nanomaterials derived from the carbonization of egg yolk, the synergetic function of the heteroatom doping, the incorporation of FeX nanoparticles, and the unique structural characteristics endows the as‐prepared sample with largely improved electrochemical performance. As expected, FeX@NPCNTs hybrid nanomaterials exhibit superior capacitive performance, including high specific capacitance, impressive rate performance, and excellent cycle stability. Using the as‐prepared FeX@NPCNTs hybrid nanomaterials as electroactive materials, a symmetric supercapacitor with high capacity and a long‐term cyclability is finally demonstrated (more than 99% capacitance retention after 50 000 cycles at a current density of 10 A g?1).  相似文献   
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