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Holt-Oram syndrome (HOS) is a developmental disorder inherited in an autosomal-dominant pattern. Affected organs are the heart and forelimbs with upper extremity skeletal defects and congenital heart malformation. In this study we present three cases of HOS in the same family. In one of these three individuals we detected a transition of C to T (CTG-GTT, V205V) in exon 7 of the TBX5 gene. This nucleotide change causes no amino acid change and potential pathologic effects remain unknown.Key Words: Holt-Oram syndrome, Congenital heart malformation, TBX5 gene  相似文献   
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Highly pathogenic influenza A/H5N1 has persistently but sporadically caused human illness and death since 1997. Yet it is still unclear how this pathogen is able to persist globally. While wild birds seem to be a genetic reservoir for influenza A, they do not seem to be the main source of human illness. Here, we highlight the role that domestic poultry may play in maintaining A/H5N1 globally, using theoretical models of spatial population structure in poultry populations. We find that a metapopulation of moderately sized poultry flocks can sustain the pathogen in a finite poultry population for over two years. Our results suggest that it is possible that moderately intensive backyard farms could sustain the pathogen indefinitely in real systems. This fits a pattern that has been observed from many empirical systems. Rather than just employing standard culling procedures to control the disease, our model suggests ways that poultry production systems may be modified.  相似文献   
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Beneficial microbes have a positive impact on the productivity and fitness of the host plant. A better understanding of the biological impacts and underlying mechanisms by which the host derives these benefits will help to address concerns around global food production and security. The recent development of omics‐based technologies has broadened our understanding of the molecular aspects of beneficial plant–microbe symbiosis. Specifically, proteomics has led to the identification and characterization of several novel symbiosis‐specific and symbiosis‐related proteins and post‐translational modifications that play a critical role in mediating symbiotic plant–microbe interactions and have helped assess the underlying molecular aspects of the symbiotic relationship. Integration of proteomic data with other “omics” data can provide valuable information to assess hypotheses regarding the underlying mechanism of symbiosis and help define the factors affecting the outcome of symbiosis. Herein, an update is provided on the current and potential applications of symbiosis‐based “omic” approaches to dissect different aspects of symbiotic plant interactions. The application of proteomics, metaproteomics, and secretomics as enabling approaches for the functional analysis of plant‐associated microbial communities is also discussed.  相似文献   
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The use of nanotechnology and biotechnology to improve the production of plant bioactive compounds is growing. Hyoscyamus reticulatus L. is a major source of tropane alkaloids with a wide therapeutic use, including treatment of Parkinson's disease and to calm schizoid patients. In the present study, hairy roots were obtained from two‐week‐old cotyledon explants of H. reticulatus L. using the A7 strain of Agrobacterium rhizogenes. The effects of different concentrations of the signaling molecule nano‐zinc oxide (ZnO) (0, 50, 100 and 200 mg/L), with three exposure times (24, 48 and 72 h), on the growth rate, antioxidant enzyme activity, total phenol contents (TPC), tropane alkaloid contents and hyoscyamine‐6‐beta‐hydroxylase (h6h) gene expression levels were investigated. Growth curve analysis revealed a decrease in fresh and dry weight of ZnO‐treated hairy roots compared to the control. ANOVA results showed that the antioxidant activity of the enzymes catalase, guaiacol peroxidase and ascorbate peroxidase was significantly higher in the ZnO‐treated hairy roots than in the control, as was the TPC. The highest levels of hyoscyamine (37%) and scopolamine (37.63%) were obtained in hairy roots treated with 100 mg/L of ZnO after 48 and 72 h, respectively. Semi‐quantitative RT‐PCR analysis revealed the highest h6h gene expression was in hairy roots treated with 100 mg/L of ZnO after 24 h. It can be concluded that ZnO is as an effective elicitor of tropane alkaloids such as hyoscyamine and scopolamine due to its enhancing effect on expression levels of the biosynthetic h6h gene.  相似文献   
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Staphylokinase (SAK) is a promising thrombolytic agent for the treatment of patients suffering from blood-clotting disorders. To increase the potency of SAK and to minimize vessel reocclusion, a new construct bearing SAK motif fused to tsetse thrombin inhibitor (TTI) via a 20-amino acid linker with 2 RGD (2 × arginine-glycine-aspartic acid inhibiting platelet aggregation via attachment to integrin receptors of platelet) was codon optimized and expressed comparatively in Pichia pastoris GS115 as a Mut+ strain and KM71H as a Muts strain. Fusion protein was optimized in terms of best expression condition and fibrinolytic activity and compared with the rSAK. Expression level of the designed construct reached up to 175 mg/L of the culture medium after 72-hr stimulation with 2.5% methanol and remained steady for 3–4 days. The highest expression was obtained at the range of 2–3% methanol. The SAK-2RGD-TT (relative activity >82%) was more active at 25–37 °C than rSAK (relative activity of 93%). Further, it showed relative activity >80% at pH ranges of 7–9. Western blot analysis showed two bands of nearly 27 and 24 kDa at ratio of 5 to 3, respectively. The specific fibrinolytic activity of the SAK-2RGD-TTI was measured as 8,269 U/mg, and 19,616 U/mg for the nonpurified and purified proteins, respectively. Deglycosylation by using tunicamycin in culture medium resulted in higher fibrinolytic activity of SAK-2RGD-TTI (2.2 fold). Consequently, compared to the rSAK, at the same equimolar proportion, addition of RGD and TTI fragments could increase fibrinolytic activity. Also, P. pastoris can be considered as an efficient host for overexpression of the soluble SAK-2RGD-TTI with high activity without requiring a complicated purification procedure.  相似文献   
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