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961.
Q Zhan  X Wang 《ZooKeys》2012,(204):41-46
A new species of Bankisus Navás, 1912,(Bankisus sparsussp. n.)is described and illustrated with the genus newly recorded from China. A key to species of Bankisus is provided.  相似文献   
962.
The ability of the soil fungi Aspergillus niger and Serpula himantioides to tolerate and solubilize manganese oxides, including a fungal-produced manganese oxide and birnessite, was investigated. Aspergillus niger and S.?himantioides were capable of solubilizing all the insoluble oxides when incorporated into solid medium: MnO(2) and Mn(2) O(3) , mycogenic manganese oxide (MnO(x) ) and birnessite [(Na(0.3) Ca(0.1) K(0.1) )(Mn(4+) ,Mn(3+) )(2) O(4) ·1.5H(2) O]. Manganese oxides were of low toxicity and A.?niger and S.?himantioides were able to grow on 0.5% (w/v) of all the test compounds, with accompanying acidification of the media. Precipitation of insoluble manganese and calcium oxalate occurred under colonies growing on agar amended with all the test manganese oxides after growth of A.?niger and S.?himantioides at 25°C. The formation of manganese oxalate trihydrate was detected after growth of S.?himantioides with birnessite which subsequently was transformed to manganese oxalate dihydrate. Our results represent a novel addition to our knowledge of the biogeochemical cycle of manganese, and the roles of fungi in effecting transformations of insoluble metal-containing compounds in the environment.  相似文献   
963.
Coronary atherosclerosis is a leading cause of coronary heart disease (CHD). Atherosclerotic lesion is a complex polygenic disease in which gene-environment interactions play a critical role in disease onset and progression. The ICAM1 gene-E469K polymorphism has been reported to be associated with CHD, but results were conflicting. A systematic review and meta-analysis of the published studies were performed to gain a clearer understanding of this association. The PubMed, Embase, and CNKI databases were searched for case–control studies published up to August 2011. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Twelve eligible studies, comprising 2,157 cases and 1,952 controls, were included in the meta-analysis. The pooled result showed that the ICAM1 gene-E469K polymorphism was significantly associated with an increased risk of CHD (OR = 1.496, 95% CI = 1.363–1.642, for the allele K vs. allele E; OR = 1.919, 95% CI = 11.635–2.253, for the K allele carriers vs. EE). Subgroup analysis supported the results in the Asian populations and in the Caucasian populations. This meta-analysis suggests that the ICAM1 gene K469E polymorphism is associated with CHD risk and the K allele is a more significant risk factor for developing CHD among Asian and Caucasians populations.  相似文献   
964.
Therapeutic targeting of melanoma antigens frequently focuses on the melanocyte differentiation or cancer-testis families. Antigen-loss variants can often result, as these antigens are not critical for tumor cell survival. Exploration of functionally relevant targets has been limited. The melanoma inhibitor of apoptosis protein (ML-IAP; livin) is overexpressed in melanoma, contributing to disease progression and treatment resistance. Improved understanding of the significance of ML-IAP immune responses in patients has possible therapeutic applications. We found ML-IAP frequently expressed in melanoma metastases by immunohistochemistry. To assess spontaneous immunity to ML-IAP, an overlapping peptide library representing full-length protein was utilized to screen cellular responses in stage I–IV patients and healthy controls by ELISPOT. A broad array of CD4+ and CD8+ cellular responses against ML-IAP was observed with novel class I and class II epitopes identified. Specific HLA-A*0201 epitopes were analyzed further for frequency of reactivity. The generation of specific CD4+ and cytotoxic T cells revealed potent functional capability including cytokine responsiveness to melanoma cell lines and tumor cell killing. In addition, recombinant ML-IAP protein used in an ELISA demonstrated high titer antibody responses in a subset of patients. Several melanoma patients who received CTLA-4 blockade with ipilimumab developed augmented humoral immune responses to ML-IAP as a function of treatment which was associated with beneficial clinical outcomes. High frequency immune responses in melanoma patients, associations with favorable treatment outcomes, and its essential role in melanoma pathogenesis support the development of ML-IAP as a disease marker and therapeutic target.  相似文献   
965.
We used trio-based whole-exome sequencing to analyze two families affected by Weaver syndrome, including one of the original families reported in 1974. Filtering of rare variants in the affected probands against the parental variants identified two different de novo mutations in the enhancer of zeste homolog 2 (EZH2). Sanger sequencing of EZH2 in a third classically-affected proband identified a third de novo mutation in this gene. These data show that mutations in EZH2 cause Weaver syndrome.  相似文献   
966.
Chen X  Fang L  Liu J  Zhan CG 《Biochemistry》2012,51(6):1297-1305
The catalytic mechanism for butyrylcholineserase (BChE)-catalyzed hydrolysis of acetylthiocholine (ATCh) has been studied by performing pseudobond first-principles quantum mechanical/molecular mechanical-free energy (QM/MM-FE) calculations on both acylation and deacylation of BChE. Additional quantum mechanical (QM) calculations have been carried out, along with the QM/MM-FE calculations, to understand the known substrate activation effect on the enzymatic hydrolysis of ATCh. It has been shown that the acylation of BChE with ATCh consists of two reaction steps including the nucleophilic attack on the carbonyl carbon of ATCh and the dissociation of thiocholine ester. The deacylation stage includes nucleophilic attack of a water molecule on the carboxyl carbon of substrate and dissociation between the carboxyl carbon of substrate and hydroxyl oxygen of Ser198 side chain. QM/MM-FE calculation results reveal that the acylation of BChE is rate-determining. It has also been demonstrated that an additional substrate molecule binding to the peripheral anionic site (PAS) of BChE is responsible for the substrate activation effect. In the presence of this additional substrate molecule at PAS, the calculated free energy barrier for the acylation stage (rate-determining step) is decreased by ~1.7 kcal/mol. All of our computational predictions are consistent with available experimental kinetic data. The overall free energy barriers calculated for BChE-catalyzed hydrolysis of ATCh at regular hydrolysis phase and substrate activation phase are ~13.6 and ~11.9 kcal/mol, respectively, which are in reasonable agreement with the corresponding experimentally derived activation free energies of 14.0 kcal/mol (for regular hydrolysis phase) and 13.5 kcal/mol (for substrate activation phase).  相似文献   
967.
968.
This study conducted quantitative kinetic modeling and in situ and temporally resolved measurements of adsorption, desorption, and re-adsorption of a commercial endoglucanase in lignocellulosic suspensions. The study defined a cellulase adsorption and desorption competition parameter, a pseudo rate of binding and desorption, binding and desorption capacity, as well as cellulase-binding reversibility (a thermodynamic property) and recyclability (a engineering parameter). The results indicate that both substrate chemical and physical structures play important roles in cellulase binding and desorption. Binding of a commercial cellulase onto a cellulosic substrate was reversible. Bindings to two different lignocellulosic substrates were almost irreversible. While lignin and its structure positively affect binding capacity to substrate, they negatively affect cellulase recyclability. Collapsing of substrate pores reduced cellulose accessibility and cellulase-binding capacity and increased reversibility and recyclability. Increasing temperature and pH increase cellulase desorption and increased binding reversibility and capacity. This study lays the foundation for developing effective cellulase recycling strategies.  相似文献   
969.
Cui X  Zhang J  Du R  Wang L  Archacki S  Zhang Y  Yuan M  Ke T  Li H  Li D  Li C  Li DW  Tang Z  Yin Z  Liu M 《Biochimica et biophysica acta》2012,1822(8):1308-1315
Heat shock factor protein 4 (HSF4) is expressed exclusively in the ocular lens and plays a critical role in the lens formation and differentiation. Mutations in the HSF4 gene lead to congenital and senile cataract. However, the molecular mechanisms causing this disease have not been well characterized. DNA damage in lens is a crucial risk factor in senile cataract formation, and its timely repair is essential for maintaining the lens' transparency. Our study firstly found evidence that HSF4 contributes to the repair of DNA strand breaks. Yet, this does not occur with cataract causative mutations in HSF4. We verify that DNA damage repair is mediated by the binding of HSF4 to a heat shock element in the Rad51 promoter, a gene which assists in the homologous recombination (HR) repair of DNA strand breaks. HSF4 up-regulates Rad51 expression while mutations in HSF4 fail, and DNA does not get repaired. Camptothecin, which interrupts the regulation of Rad51 by HSF4, also affects DNA damage repair. Additionally, with HSF4 knockdown in the lens of Zebrafish, DNA damage was observed and the protein level of Rad51 was significantly lower. Our study presents the first evidence demonstrating that HSF4 plays a role in DNA damage repair and may contribute a better understanding of congenital cataract formation.  相似文献   
970.
Lian WX  Yin RH  Kong XZ  Zhang T  Huang XH  Zheng WW  Yang Y  Zhan YQ  Xu WX  Yu M  Ge CH  Guo JT  Li CY  Yang XM 《FEBS letters》2012,586(10):1431-1438
THAP11 is an essential factor involved in ES cell pluripotency and cell growth. Here, we identified THAP11 as a novel physiological binding partner of PCBP1. In HepG2 cells, THAP11 overexpression inhibited CD44 v6 expression and cell invasion. However, when deleting the binding domain with PCBP1 or endogenous PCBP1 was knocked down, THAP11 failed to inhibit CD44 v6 expression, indicating that THAP11 regulates CD44 v6 expression through interacting with PCBP1. In HCC patients, the expression of THAP11 mRNA significantly correlated with PCBP1 mRNA expression. Our results suggest a novel role of THAP11 in CD44 alternative splicing and hepatoma invasion.  相似文献   
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