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排序方式: 共有1020条查询结果,搜索用时 31 毫秒
31.
Kyu‐Won Kwak Hong‐Soo Choi Sung‐Hee Nam Myung‐Sae Han Eunsun Kim Kwanho Park Heui‐Sam Lee 《Entomological Research》2019,49(12):534-538
This report reveals the structure of a virus extracted from the Korean horn beetle Allomyrina dichotoma. The purified virus particle was 100% identical to Allomyrina virus lef‐8 sequence registered as KM_233709.1. The structure of this virus was confirmed to be closely related to that of the Nudiviridae family, and it was rod shaped and enveloped, and observed to be of approximately the mean length of a single viral nucleocapsid of 200–210 nm and mean diameter of 100–110 nm. These results provide an insight into the structural characteristics of the Nudiviridae family that can be used for nudiviral identification. 相似文献
32.
Mesenchymal stem cells (MSCs) have been shown to down-regulate T-cell responses. However, the mechanisms underlying remain unknown. In this study, we report that BALB/c bone marrow-derived MSCs inhibit the proliferation of allogeneic T-cells in mixed lymphocyte reactions (MLR), This inhibition is dependent on cell-cell contact, and do not induce apoptosis. Furthermore, cell-cycle analyses reveal that T-cells, in the presence of MSCs, are arrested in the G0/G1 phase through. The blockage of phosphorylation of retinoblastoma protein (Rb), mediated by the p16(INK4A)-cyclin D1/cdk4 complex and p21(waf1), p27(kip1)-cyclin E/cdk2 complex pathway. Our results suggest that MSCs may perform a crucial function in the maintenance of immune homeostasis, via direct regulation of the clonal expansion of activated T-cells. The novel T-cell regulatory mechanism exhibited by MSCs may prove useful in a variety of therapeutic applications. 相似文献
33.
Kwak Mackenzie L. Gorecki Vanessa Markowsky Gregory 《Journal of Insect Conservation》2022,26(4):627-638
Journal of Insect Conservation - Urbanisation has a wide range of impacts on biodiversity, but its effects on parasitic arthropods, particularly those of bats, remain poorly studied. Ectoparasites... 相似文献
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35.
Human germinal center B cell tumors retain the ability of their nontransformed counterparts to somatically hypermutate Ig V genes by nucleotide substitution. Among a survey of 60 primary previously untreated, clonal, follicular lymphomas we have identified a rare V(H) rearrangement variant and two other in-frame nucleotide insertion/deletion variants within complementarity-determining region III of the Ig heavy chain. The neoplastic origin of the V(H) rearrangement variant was directly demonstrated in cells isolated by microdissection from malignant follicles. In all three cases a common clonal origin for the variants was demonstrated by complementarity-determining region III nucleotide sequence homology and shared somatic mutations in germline encoded positions in framework region IV. The monoclonal nature of the tumors was independently confirmed by demonstrating a single t(14;18) translocation breakpoint in the two cases with a detectable translocation. All the variants occurred in functional V(H) rearrangements, which in two cases were directly shown to encode functional Ab molecules. Both recombination-activating genes 1 and 2 were expressed in lymph node tumor cells containing the V(H) rearrangement variant, although recombination-activating gene expression among a panel of lymphomas was not limited to this variant. 相似文献
36.
Kwak E Gerald N Larochelle DA Vithalani KK Niswonger ML Maready M De Lozanne A 《Molecular biology of the cell》1999,10(12):4429-4439
We isolated a Dictyostelium cytokinesis mutant with a defect in a novel locus called large volume sphere A (lvsA). lvsA mutants exhibit an unusual phenotype when attempting to undergo cytokinesis in suspension culture. Early in cytokinesis, they initiate furrow formation with concomitant myosin II localization at the cleavage furrow. However, the furrow is later disrupted by a bulge that forms in the middle of the cell. This bulge is bounded by furrows on both sides, which are often enriched in myosin II. The bulge can increase and decrease in size multiple times as the cell attempts to divide. Interestingly, this phenotype is similar to the cytokinesis failure of Dictyostelium clathrin heavy-chain mutants. Furthermore, both cell lines cap ConA receptors but form only a C-shaped loose cap. Unlike clathrin mutants, lvsA mutants are not defective in endocytosis or development. The LvsA protein shares several domains in common with the molecules beige and Chediak-Higashi syndrome proteins that are important for lysosomal membrane traffic. Thus, on the basis of the sequence analysis of the LvsA protein and the phenotype of the lvsA mutants, we postulate that LvsA plays an important role in a membrane-processing pathway that is essential for cytokinesis. 相似文献
37.
The effect of sugar,amino acid,metal ion,and NaCl on model Maillard reaction under pH control 总被引:3,自引:0,他引:3
Summary. The color intensities was determined of Maillard reaction products (MRPs) prepared by heating each of five sugars (maltose, fructose, glucose, arabinose, and xylose) with each of 12 amino acids (aspartic acid, glutamic acid, alanine, leucine, isoleucine, valine, proline, serine, cysteine, phenylalanine, arginine, and lysine). The remaining percentages of glucose and rate of change of color intensity due to the addition of a metal ion and NaCl were monitored for nine MRPs that had been formed between glucose and each of nine amino acids (aspartic acid, glutamic acid, alanine, valine, serine, cysteine, phenylalanine, arginine, and lysine). Model MRPs were prepared in a block heater at 100°C for 1–12h with the pH value controlled at 6.5. The resulting color intensity of each MRPs formed from the basic amino acids was greater due to the higher reactivity than those from the acidic amino acids. The remaining percentage of glucose in each MRPs from the basic amino acids was lower than those from the acidic amino acids. The MRPs from the nonpolar amino acids showed an intermediate color intensity and remaining percentages of glucose between those formed from the basic and acidic amino acids. Browning tended to be accelerated in the presence of metal ions, especially Fe2+ and Cu2+, although it was affected by the property of the amino acid and heating time as well as by the type of metal ion. On the other hand, browning was greatly inhibited by a high concentration of NaCl. 相似文献
38.
Homolasonolide A and 10-desmethyllasonolide A are biologically less active than lasonolide A. The ethyl ester analogue of lasonolide A exhibited higher activity than the parent compound in some biological test. 相似文献
39.
In situ hybridization (ISH) protocols including different pre-treatment regimes were developed and compared for their effects on detecting bovine herpesvirus 4 (BoHV-4) in formalin fixed, paraffin embedded tissue. Results were compared for the hybridization and background signal intensities, and cellular morphology. We found that optimum results were obtained using enzyme treatment-thermal cycling as a pre-treatment of ISH. The results showed that the combination of protease and thermal cycling would be recommended as a means of supplementing in situ hybridization methods, especially when using long-term formalin fixed, paraffin-embedded tissue. 相似文献
40.
Escharectomy has been shown to improve the survival rates and the outcomes in burns. This observational study was conducted to assess the role of escharectomy on the inflammatory mediators in major burns. Seventeen ASA physical status II or status III adult surviving major burn patients were recruited. When the escharectomy was scheduled, a series of blood samples was obtained at -3 and -1 days preoperation, and +1 and +3 postoperation. The changing levels of endotoxin, cytokines, and adhesion molecules were measured with a quantitative sandwich immunoassay. Extensive escharectomy did not appear to have any significant impact on the levels of tumor necrosis factor alpha, interleukin-10, soluble intracellular adhesion molecule-1 and soluble vascular adhesion molecule-1. Meanwhile, endotoxin and E-selectin were significantly decreased after escharectomy. Escharectomy appeared to have a limited immunomodulatory effect on the inflammatory mediators in systemic inflammatory responses induced by major burns. This is probably related to the timing and extent of surgery, and the complex nature of burn-related inflammation. 相似文献