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The exploration of genetically superior accessions is the key source of germplasm conservation and potential breeding material for the future. To meet the demand of better yielding chickpea cultivars in Pakistan the present study was organized to select more stable and resistant lines from indigenous as well as exotic chickpea germplasm obtained from Plant Genetic Resource Institute (PGRI), National Agricultural Research Centre, Islamabad, Pakistan. For the identification and evaluation of chickpea wilt resistant lines against Fusarium oxysporum f. sp. ciceris (Schlechtends), the germplasm was tested in the field for the selection of wilt resistant lines and the PCR based molecular markers were investigated to use Marker Assisted Selection (MAS) for selection of the desirable cultivars. In field trial, 70 % accessions were resistant to wilt disease, while the remaining 30 % have shown susceptibility to the disease. A total of 5 RAPD and 15 SSR markers were screened for molecular based characterization of wilt response. The data of molecular markers were scored by the presence (1) and absence (0) of allele and subjected to statistical analysis. The analysis was based on coefficient of molecular similarity using UPGMA and sorted the germplasm into two groups based on disease response. Among the total used RAPD/SSR primers, only TA194 SSR marker showed linkage to wilt resistant locus at 85 % probability. The linkage of a marker was reconfirmed by receiver operating characteristic curve. The use of the sorted wilt resistant genotypes through SSR marker TA194 can make available ample prospect in MAS breeding for yield improvement of the crop in Pakistan.  相似文献   
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Neurochemical Research - Diabetic neuropathy is one of the most common complications of diabetes mellitus. Excess glutamate release and oxidative stress are hypothesized to be involved in the...  相似文献   
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Breast cancer ranked second among most frequent cancer in the world playing a significant role in mortality rate. Having prior knowledge on differentially expressed genes in breast cell carcinoma elucidated important indications to understand the molecular mechanism underneath breast carcinogenesis. In this study we have investigated the distinguished CSN1S1 expression in human breast cancer. We have analyzed CSN1S1 mRNA expression between cancer and normal tissues using TCGA datasets. Moreover, analysis including promoter methylation, mutations, prognosis, co-expression, gene ontology, and pathways of CSN1S1 were performed by the TCGA Wanderer, UCSC Xena, cBioPortal, PrognoScan, UALCAN, and Enricher server. We have observed low mRNA expression and high promoter methylation of CSN1S1 in cancer tissues compared to normal tissues. Furthermore, we have also identified low mRNA expression in clinicopathological patients, as well as 9 deleterious mutations with highly co-expressed protein MRC1, and significantly related signaling pathways. We have found a positive correlation between the lower expression of CSN1S1 and patients surviving with breast cancer. Here we have concluded that CSN1S1 acts as a biomarker for the surveillance and prognosis of breast cancer, and also works as a novel therapeutic target at the molecular and pathway levels.  相似文献   
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Human prion diseases are associated with misfolding or aggregation of the Human Prion Protein (HuPrP). Missense mutations in the HuPrP gene, contribute to conversion of HuPrPC to HuPrPSc and amyloid formation. Based on our previous comprehensive study, three missense mutations, from two different functional groups, i.e. disease-related mutations, and protective mutations, were selected and extensive molecular dynamics simulations were performed on these three mutants to compare their dynamics and conformations with those of the wildtype HuPrP. In addition to simulations of monomeric forms of mutants, in order to study the dominant-negative effect of protective mutation (E219K), 30-ns simulations were performed on E219K-wildtype and wildtype-wildtype dimeric forms. Our results indicate that, although after 30-ns simulations the global three-dimensional structure of models remain fairly intact, the disease-related mutations (V210I and Q212P) introduce local structural changes, i.e. close contact changes and secondary structure changes, in addition to global flexibility changes. Furthermore, our results support the loss of hydrophobic interaction due to the mutations in hydrophobic core that has been reported by previous NMR and computational studies. On the other hand, this protective mutation (E219K) results in helix elongation, and significant increases of overall flexibility of E219K mutant during 30-ns simulation. In conclusion, the simulations of dimeric forms suggest that the dominant-negative effect of this protective mutation (E219K) is due to the incompatible structures and dynamics of allelic variants during conversion process.  相似文献   
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Transplantation of stem cells using biodegradable and biocompatible nanofibrous scaffolds is a promising therapeutic approach for treating inherited retinal degenerative diseases such as retinitis pigmentosa and age-related macular degeneration. In this study, conjunctiva mesenchymal stem cells (CJMSCs) were seeded onto poly-l-lactic acid (PLLA) nanofibrous scaffolds and were induced to differentiate toward photoreceptor cell lineages. Furthermore, the effects of orientation of scaffold on photoreceptor differentiation were examined. Scanning electron microscopy (SEM) imaging, quantitative real time RT-PCR (qPCR) and immunocytochemistry were used to analyze differentiated cells and their expression of photoreceptor-specific genes. Our observations demonstrated the differentiation of CJMSCs to photoreceptor cells on nanofibrous scaffolds and suggested their potential application in retinal regeneration. SEM imaging showed that CJMSCs were spindle shaped and well oriented on the aligned nanofiber scaffolds. The expression of rod photoreceptor-specific genes was significantly higher in CJMSCs differentiated on randomly-oriented nanofibers compared to those on aligned nanofibers. According to our results we may conclude that the nanofibrous PLLA scaffold reported herein could be used as a potential cell carrier for retinal tissue engineering and a combination of electrospun nanofiber scaffolds and MSC-derived conjunctiva stromal cells may have potential application in retinal regenerative therapy.  相似文献   
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The objective of the present study was to isolate and characterize nodulating bacteria associated with wild legumes. For this purpose, we recovered twenty isolates from root nodules of five wild legume species: Melilotus alles, Melilotus officinalis, Trifolium pratense, Trifolium repens and Medicago sp. Most of the isolates were morphologically analogous with only few exceptions in colony shape, appearance and incubation time. All isolates were Gram negative except T.P2-4. Random amplification of polymorphic DNA showed genetic variation among isolates. The 16S rRNA sequence analysis revealed these isolates as Rhizobium, Sinorhizobium and Paenibacillus. Each of these was also screened for nod D and nod F genes with marked variation at these loci; however, the nucleotide sequence analysis confirmed the presence of nod genes. The assignment of strains to their hosts revealed a unique symbiotic association of Paenibacillus sp. nodulating T .pratense which is being reported here for the first time.  相似文献   
129.
Naturally derived compounds such as essential oils and natural mineral are relatively cheap, non-toxic to food grains and environmentally friendly and would be suitable alternatives for currently used chemical insecticides if they have high insecticidal effectiveness. In the present study, acute toxicity of kaolin and essential oils from Mentha pulegium and Zingiber officinale were assessed on different stages of Callosobruchus maculatus at 28?±?2?°C, 65?±?5% R. H and dark condition. The calculated LC50 values on the egg, larvae and adult stages of C. maculatus were 1.15, 2.33 and 2.18?μl/ml air for Z. officinale and 0.07, 0.11 and 0.09?μl/ml air for M. pulegium, respectively. The result showed that M. pulegium was more effective essential oil against different stages of C. maculatus compared with the Z. officinale, and also the egg and adult stages of C. maculatus were more susceptible against essential oils compared with larval stage. The LC50 values of kaolin were 0.71 and 0.18?mg/cm2 on egg and adult of C. maculatus, respectively. The combination of tested essential oils with kaolin increased mortality of C. maculatus adults compared with their application alone. It was found that tested essential oils and kaolin had high potential in controlling different stages of C. maculatus.  相似文献   
130.
A new severe little leaf disease was observed on P. grandiflora, popular as Moss-rose Purslane, widely grown in temperate zones. Characteristic symptoms, ultrastructural studies, antibiotic response and amplification of 16S ribosomal DNA fragments (about 1.5 kb) by polymerase chain reaction (PCR) from infected samples, suspect the involvement of phytoplasma as a pathogen. Nested PCR product, 1.2 kb, with primer pairs R16F2n/R16R2 used for cloning and sequencing. Comparision of the 16S rRNA gene sequences showed that the causal, PLL phytoplasma, is very close (98%) to Indian brinjal little leaf (EF186820) and “Candidatus Phytoplasma trifolii” (AY390261), 16SrVI group phytoplasmas, previously reported from India and Canada respectively. Here, the status of PLL (EF651786) is verified by computer-simulated restriction fragment length polymorphism analysis of 16S rRNA genes of the F2n/R2 sequences of closely related strains of the 16SrVI group using 17 restriction enzymes.  相似文献   
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