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561.
Viruses exist everywhere on the planet. Recent development in viral genomics confirmed that genomic information is preserved among viral subsets and can be used for phylogenetic classification of viruses and for evaluation of viral diversity in the environment. The capsid gene of T4-type bacteriophages, g23, is the most widely applied gene for evaluating the diversity of the T4-type bacteriophage family. In this study, we applied denaturing gradient gel electrophoresis to PCR products of DNA with g23-specific primers that were extracted from a Japanese paddy field under long-term fertilizer trial and obtained 39 different g23 clones at the DNA level. They showed identities of 27–99% with the clones within the NCBI database at the amino acid level. They were quite distinctive from those obtained in marine environments and most of them formed six phylogenetically novel groups in the T4-type bacteriophage family with the clones obtained from another paddy field. The existence of six novel groups was confirmed from molecular analysis of all the amino acid sequences between the primers, of the amino acid sequences excluding hypervariable region, and of those of conserved regions. These findings indicate that T4-type bacteriophage communities in paddy fields consist of previously uncharacterized members phylogenetically distant from those in marine environments. The type of fertilizers and the stage during rice cultivation were not the major factors in determining T4-type bacteriophage communities in the paddy field.  相似文献   
562.
Pemphigus is an autoimmune blistering disease characterized by lesions on the skin and mucous membranes. To date, no spontaneous cases of this disease have been reported in cynomolgus monkeys. This report describes the histopathological characteristics of spontaneous pemphigus in a cynomolgus monkey. Macroscopically, redness and scaling with pruritus were observed on the skin of the entire body. Histopathologically, the epidermis showed intercellular edema, and eosinophils and mononuclear cells infiltrated the epidermis. There was no obvious acantholysis in the epidermis. The perivascular area showed edema, and eosinophils and mononuclear cells infiltrated the vessels in the dermis. Immunohistochemically, the intercellular area in the epidermis was positive for Immunoglobulin G and Complement component 3. Serologically, anti-desmoglein 1 and desmoglein 3 antibodies in the serum were negative. From these findings, this case was diagnosed as an autoimmune skin disease, suspected to be pemphigus, and concluded as lesions being similar to those in human “pemphigus herpetiformis”.  相似文献   
563.
Fisheries Science - To test whether stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) can be used to understand the ecological connectivity of Japanese flounder Paralichthys...  相似文献   
564.
565.
The distribution of aluminum components in cross sections of pulp fibers for alum-treated handsheets was successfully measured by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. In this case, gas-phase osmium coating of paper samples is necessary for the samples to have improved stability to long-term irradiation by electron beams at high magnification during the SEM-EDX measurements. The EDX line-analysis method was superior to the elemental mapping image method in the quantification of aluminum components. According to the SEM-EDX measurement for handsheets prepared from a pulp suspension by adding 2% (on dry weight of pulp) aluminum sulfate, the aluminum components were distributed almost homogeneously in the cross sections of pulp fibers. Aluminum species with smaller sizes than those of A1(OH)3 flocs could probably penetrate the pulp fibers. Thus, aluminum components present only at the pulp fiber surfaces may contribute to retention of colloidal substances in pulp suspensions. From this aspect, a large amount of aluminum components present in the inside pulp fibers may be wasted.This report was presented at the 49th annual meeting of the Japan Wood Research Society at Tokyo, April 1997  相似文献   
566.
海北高寒草甸地区能量平衡特征   总被引:16,自引:3,他引:13  
以微气候观测为基础,研究晴天状况下海北高寒草甸地区净辐射通量、土壤热通量、感热通量和潜热通量变化等特征。结果表明:(1)该地区总辐射的水平较高,2000年4~10月达4227.049W·m-2,地表反射率在4~10月平均为0.23,在植物生长盛期的5~9月为0.22。(2)正向净辐射约占天空总辐射的56%左右;一日间土壤热通量、感热通量和潜热通量所占净辐射通量的比例在不同季节变化差异较大,在所选择的6月到9月的4个晴天个例状况平均分别所占的比例为28.6%、68.0%和3.4%,表现出潜热通量在净辐射能量的分配中所占比例较大,感热通量次之,土壤热通量则很小。(3)各通量所通过零点的时间基本一致,一般在日出后的7:00和日落前的19:00。  相似文献   
567.
在Memuro城镇,位于日本北海道Tokachi地区中部,主要种植田间抗病品种Matida。1998年马铃薯晚疫病在此品种上发生较前几年早。为了了解Matilda品种抗性降低的原因,对1996-1999年Tokachi地区的晚疫病菌基因型的时间变化进行了研究及不同基因型间病菌产生病斑能力进行了比较。在1997年以前基因型JP-1在Tokachi地区占主导地位。在1997年基因型A首次在Tokachi地区被发现并且局限在Tokachi北部。在1998和1999年基因型A遍及整个Tokachi地区,1999年其比例上升至72%。用孢子囊悬浮液接种检测不同基因型病菌对Matilda品种的致病力结果发现,基因型A比基因型JP-1和基因型B产生更大的病斑。然而通过液滴接种所有3个基因型都可产生扩展的病斑。结果表明,Matilda减少的田间抗性是由于基因型A传播到Memuro城镇的Matilda品种上所致。  相似文献   
568.
569.
When tumor tissues collected from 12 hens suffering from so-called adenocarcinoma were stained with antisera by the indirect immunofluorescent method, all of the tissues appeared to contain ovalbumin. We suggest that most adenocarcinomas in the thoracoabdomen of mature hens are oviductal in origin.  相似文献   
570.
An improved enzyme-linked immunosorbent assay (ELISA) for detection of heterophile Hanganutziu-Deicher (HD) antibodies and antigens, which are frequently detected in sera and/or cancerous tissues from patients with various cancers was developed using biotinylated chicken anti-GM3(NeuGc) antibody and avidin-horseradish peroxidase conjugate. The N-glycolylneuraminyllactosyl-ceramide, GM3(NeuGc) ganglioside was purified from horse erythrocyte membranes. The ELISA procedure required 300 ng GM3(NeuGc) antigen to coat plastic microtiter plates and 190 ng biotinylated antibody per well to give optimum product formation. The technique could detect 6 ng antigen in tissue homogenate as compared to 0.6 ng of the pure compound by inhibition. Chicken anti-GM3(NeuGc) antibody quantitatively inhibited the biotinylated antibody, however, this procedure was not suitable to quantify lower affinity HD antibody in patient sera. Immunostaining specific for HD antigen-positive cells, in tissue sections was by 4 micrograms/ml biotinylated antibody and 200 dilution of Avidin-biotinylated peroxidase complex reagent using pig intestine and lymph node as positive tissues and chicken intestine and lung as negative tissues.  相似文献   
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