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41.
Insecticide protection at the vegetative, reproductive or both vegetative and reproductive (complete) crop growth stages and untreated control was used to assess yield loss due to insect pests at the different growth stages of soybean in Ghana from 2007–2009. The objectives were to determine the economic importance of the two major insect pest guilds in soybean, viz. defoliators and pod feeders, and when to apply control measures for maximum benefit. The defoliators recorded were Podagrica spp., Ootheca mutabilis (Shalberg), Zonocerus variegatus L., Sylepta derogata F., Spodoptera littoralis Boisduval, Amsacta spp. and Helicoverpa armigera Hübner. The pod feeders recorded were the pod-sucking bugs (PSBs) Riptortus dentipes F., Thyanta sp. Aspavia armigera F., Nezara viridula L. and Dysdercus völkeri Schmidt. Generally, insect densities, pod and seed damage were lower while seed yields were significantly greater and similar in plots that were protected at the reproductive stage against PSBs and those protected at both vegetative and reproductive stages. Yield loss ranged between 25.8 and 42.8% in untreated plots, 11.1 and 34.3% in plots that were protected at the vegetative stage, and 5.2 and 11.3% in plots that were protected at the reproductive stage. There was a consistent negative correlation between yield and numbers of PSBs as well as pod and seed damage. These results showed that PSBs that attack soybean at the reproductive stage were the most important insect pests limiting soybean yield in Ghana.  相似文献   
42.
Cumin (Cuminum cyminum L.), Fennel (Foeniculum vulgare L.) and Longleaf (Falcaria vulgaris Bernh) that all belong to Apiaceae family as medicinal plants are very important in many countries. Study of genetic diversity for medicinal plant is important for researches in future. One of the methods to evaluate plant genetic diversity and classification of them is the electrophoresis of seed storage proteins. This research was conducted in order to evaluate seed protein variability in different Iranian Cumin, Fennel and Longleaf accessions and grouping them based on these proteins as a biochemical marker. For this purpose, the samples were first powdered in liquid nitrogen and seed protein was extracted with extraction buffer. Then total soluble proteins were resolved on 12.5?% sodium dodecyl sulphate polyacrylamide gel electrophoresis gels. The electrophoretic protein pattern showed 38 bands that were low polymorphism among the accessions. The result of cluster analysis showed that the accessions were classified in three groups (all 29 Cumin accessions in the first group, three Fennel ecotypes in second group and three Longleaf accessions in the last one).  相似文献   
43.
RAPD (random amplification of polymorphic DNA) was used to distinguish the genetic diversities between two genera of Chrysopa and Chrysoperla (Neuroptera, Chrysopidae). Sixty specimens were collected in different places in Kermanshah, west of Iran. The wing venation was used for identification of each type of two genera, and the gender was determined by study of external genitalia. 20 random primers were used for polymerase chain reaction. Then, the electrophoresis was used for separation of the PCR products on agarose gel. 294 bands were amplified, which 235 bands were polymorph and others (59s) determined as monomorph. The electrophoresis results showed that the primers OPA02 with 19 bands and OPA03 with 8 bands successively amplified the maximum and minimum of bands among the applied primers. The results showed that there are maximum of genetic diversity and minimum of genetic similarity between Chrysopa male (Chrysopa-M) and Chrysoperla female)Chrysoperla-F) population, in contrast, there are maximum of genetic similarity and minimum of genetic diversity between Chrysoperla-M and Chrysoperla-F, and Chrysopa-M and Chrysopa-F. There are also more genetic similarities, between males and females of Chrysopa and Chrysoperla, than between male of Chrysopa with female of Chrysoperla or vice versa.  相似文献   
44.
Optical coherence tomography (OCT) was successfully applied to visualize the mesoscale structure of three different heterotrophic biofilms. For this purpose, biofilm volumes of 4 × 4 × 1.6 mm3 were scanned with spatial resolutions lower than 20 µm within an acquisition time of 2 min. A heterogeneous structure was detected for biofilms cultivated in laminar as well as transient flow conditions. The structure was found to be more homogeneous for the biofilm grown in turbulent flow. This biofilm structure was characterized by a volumetric porosity of 0.36, whereas the porosity calculated for biofilms grown in laminar and transient conditions was 0.65. These results were directly generated from the distribution of porosity calculated from the OCT images acquired and can be linked to structural properties. Up to now, the mesoscale biofilm structure was only observable with time‐consuming and expensive studies, for example, magnetic resonance microscopy. OCT will most certainly be helpful for improved understanding and prediction of biofilm physics with respect to macroscale processes, for example, mass transfer and detachment as the information about mesoscale is easily accessible using this method. In the context of this study, we show that CLSM images do not necessarily provide an accurate representation of the biofilm structure at the mesoscale. Additionally, the typical characteristic parameters obtained from CLSM image stacks differ largely from those calculated from OCT images. Nevertheless, to determine the local distribution of biofilm constituents, microscopic methods such as confocal laser scanning microscopy are required. Biotechnol. Bioeng. 2010;107: 844–853. © 2010 Wiley Periodicals, Inc.  相似文献   
45.
The proapoptotic BCL-2 family member BAD resides in a glucokinase-containing complex that regulates glucose-driven mitochondrial respiration. Here, we present genetic evidence of a physiologic role for BAD in glucose-stimulated insulin secretion by beta cells. This novel function of BAD is specifically dependent upon the phosphorylation of its BH3 sequence, previously defined as an essential death domain. We highlight the pharmacologic relevance of phosphorylated BAD BH3 by using cell-permeable, hydrocarbon-stapled BAD BH3 helices that target glucokinase, restore glucose-driven mitochondrial respiration and correct the insulin secretory response in Bad-deficient islets. Our studies uncover an alternative target and function for the BAD BH3 domain and emphasize the therapeutic potential of phosphorylated BAD BH3 mimetics in selectively restoring beta cell function. Furthermore, we show that BAD regulates the physiologic adaptation of beta cell mass during high-fat feeding. Our findings provide genetic proof of the bifunctional activities of BAD in both beta cell survival and insulin secretion.  相似文献   
46.
The objective of this study was to use atomic force microscopy (AFM), with submicron resolution, for morphophologic and morphometric analyses of acrosome intact and acrosome-reacted human sperm heads. A mixed population of acrosome intact and reacted sperm was produced by treating capacitated sperm with A23187, which induced the acrosome reaction in approximately 50% of total sperm population. This A23187-treated sperm suspension was then plated onto a coverslip and acrosome reacted sperm were preidentified by their specific staining with rhodamine-conjugated Concanavalin A. The sperm coverslip was then air-dried and scanned by a Nanoscope IIIa atomic force microscope, using the contact mode. Top and side view images processed through the illuminate mode revealed three dimensional sperm head contour, with the highest point situated in the head posterior in both acrosome intact and acrosome reacted sperm. Maximum height, length, and width measured in 50 acrosome intact and 50 acrosome-reacted sperm were the same in both populations. However, head length at half maximum height was significantly decreased in acrosome reacted sperm (2.99 +/- 0.24 microm vs. 3.56 +/- 0.32 microm of acrosome intact sperm), due to the sudden change of the height contour from the maximum peak to the anterior tip of acrosome-reacted sperm. Our results described here can therefore be used to differentiate acrosome intact and reacted sperm from each other. This would allow future studies on subcellular changes, related to the acrosome reaction, at the submicron resolution level under more physiological conditions, since AFM does not require fixing or staining of the samples.  相似文献   
47.
48.

Background

Tuberculosis is one of the most common and deadliest infectious diseases worldwide affecting almost a third of the world’s population. Although this disease is being prevented and controlled by the Bacille Calmette Guérin (BCG) vaccine, the protective efficacy is highly variable and substandard (0–80%) in adults. Therefore, novel and effective tuberculosis vaccine that can overcome the limitations from BCG vaccine need to be developed.

Results

A novel approach of utilizing an in-trans protein surface display system of Lactobacillus plantarum carrying and displaying combination of Mycobacterium tuberculosis subunit epitope antigens (Ag85B, CFP-10, ESAT-6, Rv0475 and Rv2031c) fused with LysM anchor motif designated as ACERL was constructed, cloned and expressed in Esherichia coli Rossetta expression host. Subsequently the binding capability of ACERL to the cell wall of L. plantarum was examined via the immunofluorescence microscopy and whole cell ELISA where successful attachment and consistent stability of cell wall binding up to 4 days was determined. The immunization of the developed vaccine of L. plantarum surface displaying ACERL (Lp ACERL) via the oral route was studied in mice for its immunogenicity effects. Lp ACERL immunization was able to invoke significant immune responses that favor the Th1 type cytokine response of IFN-γ, IL-12 and IL-2 as indicated by the outcome from the cytokine profiling of spleen, lung, gastrointestinal tract (GIT), and the re-stimulation of the splenocytes from the immunized mice. Co-administration of an adjuvant consisting of Lactococcus lactis secreting mouse IL-12 (LcIL-12) with Lp ACERL was also investigated. It was shown that the addition of LcIL-12 was able to further generate significant Th1 type cytokines immune responses, similar or better than that of Lp ACERL alone which can be observed from the cytokine profiling of the immunized mice’s spleen, lung and GIT.

Conclusions

This study represents a proof of concept in the development of L. plantarum as a carrier for a non-genetically modified organism (GMO) tuberculosis vaccine, which may be the strategy in the future for tuberculosis vaccine development.
  相似文献   
49.
Molecular Biology Reports - Structural mutations providing herbicide resistance may cause a modification of the three dimensional structure of a protein which will lead to a decrease in the...  相似文献   
50.
Osteoarthritis is mediated by various types of cytokines, growth factors, and inflammatory factors that the role of the interleukin-17 family in this disease is becoming increasingly apparent. The aim of this study is to determine the association between the common polymorphisms of IL17A (including rs2275913) and IL17F (including rs2397084 and rs763780) genes with the knee osteoarthritis risk which was followed by a bioinformatics approach. In a case-control study, 254 participants consisting of 127 healthy individuals and 127 subjects with knee osteoarthritis referring to Shahid Beheshti Hospital dependents on Kashan University of Medical Sciences (Kashan, Iran) were enrolled. After samples collection, the polymorphisms genotyping was determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Finally, some bioinformatics tools were used to analyze the molecular effects of the three studied polymorphisms. Data analysis showed a significant association between rs2275913-GA genotype and the decreased risk of knee osteoarthritis (OR = 0.57, 95% CI = 0.33-0.97, P = .040). However, rs763780-AG genotype (OR = 2.29, 95%CI = 1.11-4.69, P = .024) and rs763780-G allele (OR = 2.01, 95% CI = 1.09-3.72, P = .026) were associated with an increased risk of knee osteoarthritis. However, no significant associations were found between the rs2397084 polymorphism and knee osteoarthritis risk. Our structural analysis revealed that the rs2275913 polymorphism could create a new binding site for TFII-I at the promoter region of IL17A. Also, rs2397084 and rs763780 could significantly affect the function and structure of IL17A. Based on our findings, rs2275913 and rs763780 could be considered as protective and risk factors for knee osteoarthritis, respectively. Therefore, these polymorphisms can be considered as biomarkers for the screening of knee osteoarthritis susceptible persons.  相似文献   
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