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991.
The recent epidemic spread of the North American powdery mildew Erysiphe elevata in Europe is described and discussed. Since 2002, this plant pathogenic fungus has been collected on Catalpa bignonioides, C. erubescens and C. speciosa in the Czech Republic, Germany, Hungary, Slovakia and Switzerland. The diagnostically important anamorph of E. elevata, so far unknown, is described and illustrated in detail. Type material of Erysiphe catalpae and two specimens of E. catalpae recently collected in Poland have been examined and compared with E. elevata. The anamorph as well as the teleomorph of E. catalpae proved to be easily distinguishable from E. elevata. The supposition that E. catalpae, introduced in Armenia, was based on immature ascomata of E. elevata proved to be wrong. The origin and distribution of E. catalpae are discussed, and a key to powdery mildew fungi on Catalpa spp. in Europe is provided.  相似文献   
992.
Recent increases in the incidence of primary central nervous system lymphoma (PCNSL), a rare non-Hodgkin's lymphoma arising in the brain, have been noted in both immunodeficient and immunocompetent patients. Compared with lymphomas originating outside the central nervous system, the biology of PCNSL at the molecular or cytogenetic level has not been well characterized, yet it is important to thoroughly understand the etiology of this rare malignant lymphoma if effective therapies are to be developed. This review will focus on the epidemiology, clinical aspects, histopathology, pathogenesis, and molecular genetics of this aggressive, extranodal lymphoma in immunocompetent patients.  相似文献   
993.
The seroprevalence of Hantaan virus (HTNV) in wild rodents in South Korea was analyzed. Wild rodents were trapped in 18 cities in eight provinces during 2005-2007 and on three islands and four mountains during 2008-2010. Sera were collected from 629 out of 933 trapped wild animals and examined for immunoglobulin G antibodies to HTNV using indirect immunofluorescence assays. Apodemus agrarius (80.1%) was the most frequently captured species at almost all trapping sites. The overall prevalence of HTNV antibodies was 0.26 (162/629). Seropositive individuals were more frequent in cities (32.2%, n=410) than on islands (14.0%, n=57) or mountains (13.6%, n= 162). HTNV antibody-positive rate was higher in the fall (29.6%, n=253) than in the spring (23.1%, n=376). A. agrarius had the highest prevalence of HTNV antibodies (26.9%, n=561) of all tested species. Considering all the individuals, the prevalence of HTNV antibodies was higher in males (29.2%, n=250) than in females (22.3%, n=305). Our results show that HTNV is widely distributed throughout South Korea, and that HTNV infection of wild rodents is affected by their habitat, species, sex, and season.  相似文献   
994.
995.
We report an allele-specific sequencing method using allele-specific long-range polymerase chain reaction (PCR) to determine if multiple (specifically, more than three) single nucleotide polymorphisms (SNPs) are located on the same allele. We sequenced the glucocorticoid receptor (GR) gene as a model and detected four nucleotide changes, including two novel variations, in intron 4 and exons 6, 8, and 9 alpha in four of the investigated cell lines. The terminal SNPs (intron 4 and exon 9 alpha) were separated by 19 kb. Following SNP identification, the first round PCR allele-specific primers are designed at the both distal SNP sites (intron 4 and exon 9 alpha), placing the SNP positions at the primer 3'-end. Using these first round PCR products as template, the second round PCR was performed to separately amplify exons 6 and 8. These second round PCR products were subsequently sequenced. The sequencing results showed that the four SNPs were located on the same allele, i.e., forming a haplotype. This allele-specific long-range PCR/sequencing (ALP/S) method is rapid and applicable to the allelic assignment for more than three SNPs.  相似文献   
996.
GTP-bound Ras adopts two interconverting conformations, "inactive" state 1 and "active" state 2. However, the tertiary structure of wild-type (WT) state 1 remains unsolved. Here we solve the state 1 crystal structures of H-Ras WT together with its oncogenic G12V and Q61L mutants. They assume open structures characterized by impaired interactions of both Thr-35 in switch I and Gly-60 in switch II with the γ-phosphate of GTP and possess two surface pockets of mutually different shapes unseen in state 2, a potential target for selective inhibitor development. Furthermore, they provide a structural basis for the low GTPase activity of state 1.  相似文献   
997.
Shin  Jong-ahm  Miura  Akio 《Hydrobiologia》1990,(1):397-400
Crosses between genotypically distinct thalli of the monoecious species Porphyra yezoensis were carried out using immature thallus fragments from green- and red-type color mutants and also wild-type thalli. As the genes governing the mutants are monogenic, recessive to the wild-type, and belong to the same linkage group, the degree of self-fertilization could be estimated based on the pigmentation of the resultant diploid conchocelis. The degree of self-fertilization in the cross between the green-type and the wild-type was 48.5–55.0%, and in the cross between the red-type and the wild-type was 45.1–56.5%. In the cross between the green- and red-type mutants, the degree of self-fertilization was 46.0–54.5% when the green-type was the female parent, and was 44.8–55.6% when the red-type was the female parent.  相似文献   
998.
999.
YKL-40, a chitinase-3-like protein 1 (CHI3L1) or human cartilage glycoprotein 39 (HC gp-39), is expressed and secreted by various cell-types including macrophages, chondrocytes, fibroblast-like synovial cells and vascular smooth muscle cells. Its biological function is not well elucidated, but it is speculated to have some connection with inflammatory reactions and autoimmune diseases. Although having important biological roles in autoimmunity, there were only attempts to elucidate relationships of YKL-40 with a single or couple of diseases in the literature. Therefore, in order to analyze the relationship between YKL-40 and the overall diseases, we reviewed 51 articles that discussed the association of YKL-40 with rheumatoid arthritis, psoriasis, systemic lupus erythematosus, Behçet disease and inflammatory bowel disease. Several studies showed that YKL-40 could be assumed as a marker for disease diagnosis, prognosis, disease activity and severity. It is also shown to be involved in response to disease treatment. However, other studies showed controversial results particularly in the case of Behçet disease activity. Therefore, further studies are needed to elucidate the exact role of YKL-40 in autoimmunity and to investigate its potential in therapeutics.  相似文献   
1000.
Transforming growth factor-beta1 (TGF-beta1) is a key mediator in tissue repair and fibrosis. Using small interference RNA (siRNA), the role of Smad2 and Smad3 in TGF-beta stimulation of human lung fibroblast contraction of collagenous matrix and induction of alpha-SMA and the role of alpha-SMA in contraction were assessed. HFL-1 cells were transfected with Smad2, Smad3 or control-siRNA, and cultured in floating Type I collagen gels +/- -TGF-beta1. TGF-beta1 augmented gel contraction in Smad2-siRNA- and control-siRNA-treated cells, but had no effect in Smad3-siRNA-treated cells. Similarly, TGF-beta1 upregulated alpha-SMA in Smad2-siRNA- and control-siRNA-treated cells, but had no effect on Smad3-siRNA-treated cells. Alpha-SMA-siRNA-treated cells did not contact the collagen gels with or without TGF-beta1, suggesting alpha-SMA is required for gel contraction. Thus, Smad3 mediates TGF-beta1-induced contraction and alpha-SMA induction in human lung fibroblasts. Smad3, therefore, could be a target for blocking contraction of human fibrotic tissue induced by TGF-beta1.  相似文献   
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