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11.
12.

Background

TNF-α and IFN-γ play a role in the development of mucosal damage in celiac disease (CD). Polymorphisms of TNFA and IFNG genes, as well as of the TNFRSF1A gene, encoding the TNF-α receptor 1, might underlie different inter-individual disease susceptibility over a common HLA risk background. The aims of this study were to ascertain whether five SNPs in the TNFA promoter (-1031T>C,-857C>T,-376G>A,-308G>A,-238G>A), sequence variants of the TNFRSF1A gene and IFNG +874A>T polymorphism are associated with CD in a HLA independent manner.

Methods

511 children (244 CD, 267 controls) were genotyped for HLA, TNFA and INFG (Real Time PCR). TNFRSF1A variants were studied (DHPLC and sequence).

Results

Only the rare TNFA-1031C (OR=0.65, 95% CI:0.44-0.95), -857T (OR=0.42, 95% CI:0.27-0.65), -376A (OR=2.25, 95% CI:1.12-4.51) and -308A (OR=4.76, 95% CI:3.12-7.26) alleles were significantly associated with CD. One TNFRSF1A variant was identified (c.625+10A>G, rs1800693), but not associated with CD. The CD-correlated TNFA SNPs resulted in six haplotypes. Two haplotypes were control-associated (CCGG and TTGG) and three were CD-associated (CCAG, TCGA and CCGA). The seventeen inferred haplotype combinations were grouped (A to E) based on their frequencies among CD. Binary logistic regression analysis documented a strong association between CD and HLA (OR for intermediate risk haplotypes=178; 95% CI:24-1317; OR for high risk haplotypes=2752; 95% CI:287-26387), but also an HLA-independent correlation between CD and TNFA haplotype combination groups. The CD risk for patients carrying an intermediate risk HLA haplotype could be sub-stratified by TNFA haplotype combinations.

Conclusion

TNFA promoter haplotypes associate with CD independently from HLA. We suggest that their evaluation might enhance the accuracy in estimating the CD genetic risk.  相似文献   
13.
Stonis JR  Diskus A 《Zoological science》2007,24(12):1286-1291
We describe Tischeria gouaniae sp. n. from the tropical forests of Belize. The new species is a leaf-miner of Gouania polygama (Rhamnaceae). Together with the related T. bifurcata Braun, it is among the most striking representatives of Tischeria. Both species possess a pseudognathos and very broad aedeagus fused with extremely long lateral processes of the juxta. The new species differs from T. bifurcata in the broadly rounded vinculum, spiny juxta, and slender apical processes of the aedeagus, and in its host plant. The external features and male genitalia of Tischeria gouaniae sp. n. are figured and described. A checklist and distribution map for all nine currently known Tischeria species from North and South America are given. Most American species are known from USA, but others are now known from tropical forest habitats of Central America, the Caribbean, and Guyana. Host-plants are known for five of the nine species reviewed here, belonging to four genera and two plant families (Fagaceae and Rhamnaceae).  相似文献   
14.
Nonsyndromic orofacial clefting (NS-OFC) is a common complex multifactorial trait with a considerable genetic component and a number of candidate genes suggested by various approaches. Twenty biallelic and microsatellite DNA markers in the strong candidate loci TGFA, TGFB3, GABRB3, RARA, and BCL3 were analysed for allelic association with the NS-OFC phenotype in 112 nuclear families (proband + both parents) from Lithuania by using the transmission disequilibrium test (TDT). Associations were found between the TGFA gene marker rs2166975 and nonsyndromic cleft palate only (CPO) phenotype (p = 0.045, df 1) as well as between the D2S292 marker and the cleft lip with or without cleft palate (CL/CP) phenotype in allele-wise TDT (P = 0.005, df 9) and genotype-wise TDT (P = 0.021, df 24). A weak association (P = 0.085, df 3) of the BCL3 marker (BCL3 gene) with the risk of CPO was also found. Thus our initial results support the contribution of allelic variation in the TGFA locus to the aetiology of CL/CP in the population of Lithuania but they do not point to TGFA as a major causal gene. Different roles of the TGFA and BCL3 genes in the susceptibility to NS-OFC phenotypes are suggested.  相似文献   
15.
Mutations at protein–protein recognition sites alter binding strength by altering the chemical nature of the interacting surfaces. We present a simple surface energy model, parameterized with empirical values, yielding mean energies of ?48 cal mol?1 Å?2 for interactions between hydrophobic surfaces, ?51 to ?80 cal mol?1 Å?2 for surfaces of complementary charge, and 66–83 cal mol?1 Å?2 for electrostatically repelling surfaces, relative to the aqueous phase. This places the mean energy of hydrophobic surface burial at ?24 cal mol?1 Å?2. Despite neglecting configurational entropy and intramolecular changes, the model correlates with empirical binding free energies of a functionally diverse set of rigid‐body interactions (r = 0.66). When used to rerank docking poses, it can place near‐native solutions in the top 10 for 37% of the complexes evaluated, and 82% in the top 100. The method shows that hydrophobic burial is the driving force for protein association, accounting for 50–95% of the cohesive energy. The model is available open‐source from http://life.bsc.es/pid/web/surface_energy/ and via the CCharpPPI web server http://life.bsc.es/pid/ccharppi/ . Proteins 2015; 83:640–650. © 2015 Wiley Periodicals, Inc.  相似文献   
16.
17.
Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV) and Apple mosaic virus are economically important viruses infecting fruit tree species worldwide. To evaluate the occurrence of these pome fruit viruses in Latvia, a large‐scale survey was carried out in 2007. Collected samples were tested for infection by DAS ELISA and multiplex RT‐PCR. The accuracy of the detection of the viruses in multiplex RT‐PCR was confirmed by sequencing amplified PCR fragments. The results showed a wide occurrence of viruses in apple and pear commercial orchards established from non‐tested planting material. More than 89% of the tested apple trees and more than 60% of pear trees were infected with one or more pome fruit viruses. Analyses showed that the high occurrence of viruses in several apple cultivars is due to the propagation of infected clonal rootstocks and scions from infected mother trees. Sequence analyses targeting the 3′‐terminal region of the tested viruses showed various degrees of genetic diversity within respective virus isolates. This is the first report of the occurrence of ACLSV, ASGV and ASPV in apple and pear trees in Latvia and demonstrates their genetic diversity in different host genotypes.  相似文献   
18.

Background

Patients with epilepsy often suffer from other important conditions. The existence of such co-morbidities is frequently not recognized and their relationship with epilepsy usually remains unexplained.

Methodology/Principal Findings

We describe three patients with common, sporadic, non-syndromic epilepsies in whom large genomic microdeletions were found during a study of genetic susceptibility to epilepsy. We performed detailed gene-driven clinical investigations in each patient. Disruption of the function of genes in the deleted regions can explain co-morbidities in these patients.

Conclusions/Significance

Co-morbidities in patients with epilepsy can be part of a genomic abnormality even in the absence of (known) congenital malformations or intellectual disabilities. Gene-driven phenotype examination can also reveal clinically significant unsuspected condition.  相似文献   
19.
Tischeria urticicolella (Ghesquière, 1940)--a poorly studied species from the Democratic Republic of Congo and formerly known as a member of the Gracillariidae--is redescribed and reported as belonging to the Tischeriidae for the first time. The external features and male genitalia are figured and described. A checklist and distribution map for all 18 Tischeriidae species currently recorded from Africa (including the Canary Islands) are given.  相似文献   
20.
The objective of the present work was to develop a method to distinguish between metabolically inactive and active parts of plant roots. White clover (Trifolium repens L.) roots were stained with 2,3,5-triphenyltetrazolium chloride (TTC) followed by root colour classification with an interactive scanner-based image analysis programme (WinRHIZO). Roots inactivated by boiling were unstained and pale brown, whereas fresh samples with predominantly metabolically active roots turned dark red, red or pale red after staining. A small amount of very young, presumable active roots (0.8% of total active root length) failed to stain red with TTC. The colour analysis of inactive and active roots was based on four colour classes for boiled roots and seven classes for fresh roots, respectively, as defined upon visual examination of images. Pixel colours falling outside the defined classes were allocated to the nearest defined class – an option that increased objectivity and stability and reduced the required number of colour classes. For the fresh white clover roots, 75–86% of the total root length was determined as active, while 3–7% of the boiled roots fell into the same category. The percentage of total root length measured by WinRHIZO that was identified as metabolically active was linearly correlated with the percentage of fresh roots in mixtures of fresh and boiled roots (R2=0.99). Colour classes chosen à priori from one experiment could be used to distinguish fairly satisfactorily between active and inactive roots of another white clover cultivar grown under other conditions, but failed to classify activity in ryegrass (Lolium multiflorum Lam.) root samples. In the latter case, colour classes needed to be re-defined in order to produce reliable data. Our work shows that WinRHIZOs colour identification sub-module provides a new promising tool to classify root activity as identified after staining with TTC, but colour classes must be carefully evaluated on every new occasion.  相似文献   
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