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331.
A novel class of experimental fungicides has been discovered, which consists of special tetrasubstituted imidazoles. They are highly active against important phytopathogens, such as Botrytis cinerea (grey mould), Uncinula necator (grape powdery mildew), Mycosphaerella graminicola (wheat leaf blotch) and Alternaria solani (potato and tomato early blight). Their fungicidal efficacy is due to their ability to promote fungal tubulin polymerization, which leads to a disruption of microtubule dynamics. These imidazoles are five-membered ring analogs of similar substituted triazolopyrimidines and pyridazines with the same mode of action. A concise four-step synthesis route has been used to prepare them from commercially available starting materials.  相似文献   
332.
A healthy root system is vital for tissue culture plantlet survival and rapid adaptation from the in vitro microenvironment to glasshouse conditions. Optimization of the root induction medium is an effective way to promote root induction and elongation. Levels of three auxins (α-naphthaleneacetic acid [NAA], 3-indoleacetic acid [IAA], and 3-indolebutyric acid [IBA]) and copper sulfate (CuSO4) have been investigated in a series of experiments with a sorghum inbred line, Tx430. Significant improvement in root proliferation and shoot growth were observed on Murashige and Skoog (MS) medium supplemented with 1 μmol/L CuSO4, 1 mg/L NAA, 1 mg/L IAA, and 1 mg/L IBA. On average, one explant (the original in vitro-derived shoot) of Tx430 regenerated 56.7 roots, which was 20-fold higher on the optimal medium than on MS control medium. Another tested genotype SA281 showed similar response patterns as Tx430 across media. In addition, 100% of Tx430 and SA281 plantlets originating from the optimized root induction medium all survived after being transferred to potting soil in the glasshouse. The results demonstrate that a combination of auxins (NAA, IAA, and IBA) and CuSO4 together at optimal concentrations provide additive effects on promoting root proliferation and explant growth of in vitro sorghum in root induction medium, and subsequently resulted in 100% survival rate of plantlets ex tissue culture. Compared with two published and frequently used root induction media, the optimized medium significantly enhanced root induction and plantlet growth.  相似文献   
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RAD51 is an important component of double-stranded DNA–repair mechanisms that interacts with both BRCA1 and BRCA2. A single-nucleotide polymorphism (SNP) in the 5′ untranslated region (UTR) of RAD51, 135G→C, has been suggested as a possible modifier of breast cancer risk in BRCA1 and BRCA2 mutation carriers. We pooled genotype data for 8,512 female mutation carriers from 19 studies for the RAD51 135G→C SNP. We found evidence of an increased breast cancer risk in CC homozygotes (hazard ratio [HR] 1.92 [95% confidence interval {CI} 1.25–2.94) but not in heterozygotes (HR 0.95 [95% CI 0.83–1.07]; P=.002, by heterogeneity test with 2 degrees of freedom [df]). When BRCA1 and BRCA2 mutation carriers were analyzed separately, the increased risk was statistically significant only among BRCA2 mutation carriers, in whom we observed HRs of 1.17 (95% CI 0.91–1.51) among heterozygotes and 3.18 (95% CI 1.39–7.27) among rare homozygotes (P=.0007, by heterogeneity test with 2 df). In addition, we determined that the 135G→C variant affects RAD51 splicing within the 5′ UTR. Thus, 135G→C may modify the risk of breast cancer in BRCA2 mutation carriers by altering the expression of RAD51. RAD51 is the first gene to be reliably identified as a modifier of risk among BRCA1/2 mutation carriers.  相似文献   
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Objective

The purpose of this study was to develop a core set of indicators that could be used for measuring and monitoring the performance of primary health care organizations'' capacity and strategies for enhancing equity-oriented care.

Methods

Indicators were constructed based on a review of the literature and a thematic analysis of interview data with patients and staff (n = 114) using procedures for qualitatively derived data. We used a modified Delphi process where the indicators were circulated to staff at the Health Centers who served as participants (n = 63) over two rounds. Indicators were considered part of a priority set of health equity indicators if they received an overall importance rating of>8.0, on a scale of 1–9, where a higher score meant more importance.

Results

Seventeen indicators make up the priority set. Items were eliminated because they were rated as low importance (<8.0) in both rounds and were either redundant or more than one participant commented that taking action on the indicator was highly unlikely. In order to achieve health care equity, performance at the organizational level is as important as assessing the performance of staff. Two of the highest rated “treatment” or processes of care indicators reflects the need for culturally safe and trauma and violence-informed care. There are four indicators that can be used to measure outcomes which can be directly attributable to equity responsive primary health care.

Discussion

These indicators and subsequent development of items can be used to measure equity in the domains of treatment and outcomes. These areas represent targets for higher performance in relation to equity for organizations (e.g., funding allocations to ongoing training in equity-oriented care provision) and providers (e.g., reflexive practice, skill in working with the health effects of trauma).  相似文献   
337.
Enhancer of zeste homolog 2 (EZH2) is the catalytic subunit of the polycomb repressive complex 2 (PRC2) that includes noncatalytic subunits suppressor of zeste 12 (SUZ12) and embryonic ectoderm development (EED). When present in PRC2, EZH2 catalyzes trimethylation on lysine 27 residue of histone H3 (H3K27Me3), resulting in epigenetic silencing of gene expression. Here, we investigated the expression and function of EZH2 in epithelial ovarian cancer (EOC). When compared with primary human ovarian surface epithelial (pHOSE) cells, EZH2, SUZ12, and EED were expressed at higher levels in all 8 human EOC cell lines tested. Consistently, H3K27Me3 was also overexpressed in human EOC cell lines compared with pHOSE cells. EZH2 was significantly overexpressed in primary human EOCs (n = 134) when compared with normal ovarian surface epithelium (n = 46; P < 0.001). EZH2 expression positively correlated with expression of Ki67 (P < 0.001; a marker of cell proliferation) and tumor grade (P = 0.034) but not tumor stage (P = 0.908) in EOC. There was no correlation of EZH2 expression with overall (P = 0.3) or disease-free survival (P = 0.2) in high-grade serous histotype EOC patients (n = 98). Knockdown of EZH2 expression reduced the level of H3K27Me3 and suppressed the growth of human EOC cells both in vitro and in vivo in xenograft models. EZH2 knockdown induced apoptosis of human EOC cells. Finally, we showed that EZH2 knockdown suppressed the invasion of human EOC cells. Together, these data demonstrate that EZH2 is frequently overexpressed in human EOC cells and its overexpression promotes the proliferation and invasion of human EOC cells, suggesting that EZH2 is a potential target for developing EOC therapeutics.  相似文献   
338.
The ability of the wheat Lr34 multipathogen resistance gene (Lr34res) to function across a wide taxonomic boundary was investigated in transgenic Sorghum bicolor. Increased resistance to sorghum rust and anthracnose disease symptoms following infection with the biotrophic pathogen Puccinia purpurea and the hemibiotroph Colletotrichum sublineolum, respectively, occurred in transgenic plants expressing the Lr34res ABC transporter. Transgenic sorghum lines that highly expressed the wheat Lr34res gene exhibited immunity to sorghum rust compared to the low‐expressing single copy Lr34res genotype that conferred partial resistance. Pathogen‐induced pigmentation mediated by flavonoid phytoalexins was evident on transgenic sorghum leaves following P. purpurea infection within 24–72 h, which paralleled Lr34res gene expression. Elevated expression of flavone synthase II, flavanone 4‐reductase and dihydroflavonol reductase genes which control the biosynthesis of flavonoid phytoalexins characterized the highly expressing Lr34res transgenic lines 24‐h post‐inoculation with P. purpurea. Metabolite analysis of mesocotyls infected with C. sublineolum showed increased levels of 3‐deoxyanthocyanidin metabolites were associated with Lr34res expression, concomitant with reduced symptoms of anthracnose.  相似文献   
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Two genes were isolated from a rice genomic library and the coding region of their corresponding cDNAs generated by RT-PCR. These single copy genes, designated ORYsa;Sultr1;1 and ORYsa;Sultr4;1, encode putative sulfate transporters. Both genes encode proteins with predicted topologies and signature sequences of the H+/SO42- symporter family of transporters and exhibit a high degree of homology to other plant sulfate transporters. ORYsa;Sultr1;1 is expressed in roots with levels of expression being strongly enhanced by sulfate starvation. In situ hybridization experiments revealed that ORYsa;Sultr1;1 expression is localized to the main absorptive region of roots. This gene probably encodes a transporter that is responsible for uptake of sulfate from the soil solution. In contrast, ORYsa;Sultr4;1 was expressed in both roots and shoots and was unresponsive to the sulfur status of the plant. The sequence of ORYsa;Sultr4;1 contains a possible plastid-targeting transit peptide which may indicate a role in transport of sulfate to sites of sulfate reduction in plastids. The role of the transporter encoded by ORYsa;Sultr4;1 is likely to be significantly different fromORYsa;Sultr1;1. These are the first reports of isolation of genes encoding sulfate transporters from rice and provide a basis for further studies involving sulfate transport.  相似文献   
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