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1.

Background  

The integration of many aspects of protein/DNA structure analysis is an important requirement for software products in general area of structural bioinformatics. In fact, there are too few software packages on the internet which can be described as successful in this respect. We might say that what is still missing is publicly available, web based software for interactive analysis of the sequence/structure/function of proteins and their complexes with DNA and ligands. Some of existing software packages do have certain level of integration and do offer analysis of several structure related parameters, however not to the extent generally demanded by a user.  相似文献   
2.

Background  

Pichia pastoris has been recognized as an effective host for recombinant protein production. A number of studies have been reported for improving this expression system. However, its physiology and cellular metabolism still remained largely uncharacterized. Thus, it is highly desirable to establish a systems biotechnological framework, in which a comprehensive in silico model of P. pastoris can be employed together with high throughput experimental data analysis, for better understanding of the methylotrophic yeast's metabolism.  相似文献   
3.
The medicinal potentials of the methanol extracts of the leaves and stems of Halleria lucida (Scrophulariaceae) were evaluated by assessing their antibacterial and antioxidant properties in vitro using standard procedures. The antioxidant activities of methanol extract of the leaves as determined by the ABTS, DPPH, proanthocyanidins and total flavonoids were higher than that of the stem. On the other hand, the total phenols, the flavonoids and the FRAP contents of the stem were higher than that of the leaves. The extracts however showed poor activity against both Gram-positive and Gram-negative bacteria. The methanol extract of the stem showed activities against Bacillus cereus and Staphylococcus epidermidis at MIC of 1.0 mg/ml. The methanol extract of the leaves did not show activity against any of the organisms used in this study. This study has to some extent validated the medicinal potential of the leaves and stems of H. lucida.  相似文献   
4.
Wild tubers of Dioscorea bulbifera (Db) and Dioscorea hirtiflora (Dh) mainly used as sources of famine food and in herbal preparations are often indiscriminately collected in Africa and Asia. Therefore, there is the need to complement wild sourcing of the tubers to promote their conservation. The present study reports in vitro tuberous induction (80%) for the first time from Dh cultured on MS?+?NAA (2.5 mg/L) with IC50 of 472.5?±?1.77 µg/mL using DPPH, whereas tuberous root (60%) from Db on MS?+?Kn (2.5 mg/L)?+?NAA (0.25 mg/L) had IC50 of 26.97?±?1.00 µg/mL. Genetic fidelity assessment of in vitro plants compared to the wild plants revealed similar amplicon size of amplified DNA using trnH–psbA and rbcL. Similarly, micromorphological diagnostic features like oil gland, crystals (raphides), trichome and stomata type were obtained from the epidermal peels of the wild and in vitro plants. The ethyl acetate (EtOAc) extract of the flesh of Dh (wild) had the highest catechin content (108.3?±?0.69 µg/g DW). Protocatechuic acid was highest in the methanol (MeOH) extract of the flesh of Dh (0.42?±?0.02 µg/g DW), while it was detected in trace amount in the in vitro tuberous roots of MeOH extracts of Dh treated with NAA. The in vitro protocol developed in this study could be employed to multiply Dioscorea bulbifera L. and Dioscorea hirtiflora Benth. to offer genetically stable clones for the optimization of bioactive compounds and germplasms conservation.  相似文献   
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6.
This commentary highlights the effectiveness of optoelectronic properties of polymer semiconductors based on recent results emerging from our laboratory, where these materials are explored as artificial receptors for interfacing with the visual systems. Organic semiconductors based polymer layers in contact with physiological media exhibit interesting photophysical features, which mimic certain natural photoreceptors, including those in the retina. The availability of such optoelectronic materials opens up a gateway to utilize these structures as neuronal interfaces for stimulating retinal ganglion cells. In a recently reported work entitled “A polymer optoelectronic interface provides visual cues to a blind retina,” we utilized a specific configuration of a polymer semiconductor device structure to elicit neuronal activity in a blind retina upon photoexcitation. The elicited neuronal signals were found to have several features that followed the optoelectronic response of the polymer film. More importantly, the polymer-induced retinal response resembled the natural response of the retina to photoexcitation. These observations open up a promising material alternative for artificial retina applications.  相似文献   
7.

Background

Influenza pandemic remains a serious threat to human health. Viruses of avian origin, H5N1, H7N7 and H9N2, have repeatedly crossed the species barrier to infect humans. Recently, a novel strain originated from swine has evolved to a pandemic. This study aims at improving our understanding on the pathogenic mechanism of influenza viruses, in particular the role of non-structural (NS1) protein in inducing pro-inflammatory and apoptotic responses.

Methods

Human lung epithelial cells (NCI-H292) was used as an in-vitro model to study cytokine/chemokine production and apoptosis induced by transfection of NS1 mRNA encoded by seven infleunza subtypes (seasonal and pandemic H1, H2, H3, H5, H7, and H9), respectively.

Results

The results showed that CXCL-10/IP10 was most prominently induced (> 1000 folds) and IL-6 was slightly induced (< 10 folds) by all subtypes. A subtype-dependent pattern was observed for CCL-2/MCP-1, CCL3/MIP-1α, CCL-5/RANTES and CXCL-9/MIG; where induction by H5N1 was much higher than all other subtypes examined. All subtypes induced a similar temporal profile of apoptosis following transfection. The level of apoptosis induced by H5N1 was remarkably higher than all others. The cytokine/chemokine and apoptosis inducing ability of the 2009 pandemic H1N1 was similar to previous seasonal strains.

Conclusions

In conclusion, the NS1 protein encoded by H5N1 carries a remarkably different property as compared to other avian and human subtypes, and is one of the keys to its high pathogenicity. NCI-H292 cells system proves to be a good in-vitro model to delineate the property of NS1 proteins.
  相似文献   
8.
9.
Laboratory studies were carried out to determine the effect of sex and age on the susceptibility of tsetse, Glossina morsitans morsitans and G. m. centralis, to the entomopathogenic fungus, Metarhizium anisopliae. Both species of host flies were susceptible to fungal infection. Female flies were generally more susceptible than male flies. Three host ages (40, 20, and <1 day-old) were used; the youngest group was most resistant to fungal infection. Interactions between species, sex and age were significant on many occasions. Age usually accounted for the largest variability in mortality, followed by sex. All flies of age 40 days died between 7 and 8 days after infection whereas some of the younger flies, especially age 0, lived longer than 10 days. Log10 day probit (LDP) mortality regressions fitted well to most of the data sets. LDP slopes were significant and high, ranging between 4.3 and 12.8, indicating a generally high mortality rate of increase over days. The slopes differed significantly between species, sexes, and ages, but grouping by age was more intra homogeneous than by species or sex. The 50% lethal time mortalities (LT50) ranged between 4 and 7 days for age 0, 3 and 6 days for age 20, and about 5 days for age 40. Corresponding ranges of the LT95 were 8 to 20, 5 to 10, and 6 to 7 days for ages 0, 20 and 40, respectively. The significance of these results in the fungal disease transmission by tsetse is discussed.  相似文献   
10.
Earlier opinions that Macroramphosus is monotypic are refuted, with two species apparently occurring in Japan (tentatively identified as M. gracilis and M. scolopax). In postsettlement young and adults, the former is characterized by a dark slender body (vs. red-orange and deep) and short second dorsal fin spine with a smooth posterior margin (vs. long spine with a serrated margin). Food habits also differ between the two species, which are either plankton or benthos feeders. Two types of Macroramphosus larvae and juveniles occurring at the surface were recognized, one having a straight ventral body profile of the body (identified here as M. gracilis) and the other having a notch in the anal region. The dark body of postsettlement M. gracilis is considered to be a retention of the character suited to the neustonic distribution of the larval and juvenile stages, the species remaining to ca. 40mm in standard length (SL) in that habitat (vs. to ca. 12mm SL in M. scolopax).  相似文献   
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