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111.
The complete genome sequences of two Brazilian wild-type rabies viruses (RABV), a BR-DR1 isolate from a haematophagous bat (Desmodus rotundus) and a BR-AL1 isolate from a frugivorous bat (Artibeus lituratus), were determined. The genomes of the BR-DR1 and BR-AL1 had 11,923 and 11,922 nt, respectively, and both encoded the five standard genes of rhabdoviruses. The complete nucleotide sequence identity between the BR-DR1 and BR-AL1 isolates was 97%. The BR-DR1 and BR-AL1 isolates had some conserved functional sites revealed by the fixed isolates, whereas both isolates had unique amino acid substitutions in the antigenic region IV of the nucleocapsid gene. Therefore, it is speculated that both isolates were nearly identical in virologic character. According to our phylogenetic analysis based on the complete genomes, both isolates belonged to genotype 1, and to the previously defined "vampire bat-related RABV lineage" which consisted of mainly D. rotundus- and A. lituratus-isolates; however, a branch pattern with high bootstrap values suggested that BR-DR1 was more closely related to the 9001FRA isolate, which was collected from a dog bitten by a bat in French Guiana, than to BR-AL1. This result suggests that the vampire bat-related RABV lineage includes Brazilian vampire bat and Brazilian frugivorous bat RABV and is further divided into Brazilian vampire bat and Brazilian frugivorous bat RABV sub-lineages. The phylogenetic analysis based on the complete genomes was valuable in discriminating among very closely related isolates.  相似文献   
112.
An immunoglobulin G (IgG) subclass response against equine herpesvirus type 1 (EHV-1) infection was investigated in horses that were na?ve to EHV-1/4 and those that had previously been exposed to EHV-4. The IgG subclass response was determined by an ELISA using EHV-1-specific recombinant gG protein as an antigen. In most horses na?ve to EHV-1/4, IgGa, IgGb, and IgG(T) were induced after experimental infection with EHV-1. In contrast, a subclass response dominated by IgGa and IgGb, with no apparent increase in IgG(T), was observed after EHV-1 infection in horses previously infected with EHV-4. Horses naturally infected with EHV-1 in the field showed similar responses. These results indicated that pre-infection with EHV-4 induced a Th-1-biased IgG subclass response against subsequent EHV-1 infection.  相似文献   
113.
A 28-month-old African hedgehog was referred to our hospital with progressive tetraparesis. On the first presentation, the hedgehog was suspected as having wobbly hedgehog syndrome (WHS) and the animal was treated with medication and rehabilitation. The animal died 22 days after onset. Pathological examination revealed that the animal was involved in astrocytoma between the medulla oblongata and the spinal cord (C1). This report indicates that a primary central nervous system tumor should be considered as one of the differential diagnoses for hedgehogs presenting with progressive paresis, together with WHS.  相似文献   
114.
In terrestrial mammals, the surface molecule CD34 is used as a marker to identify hematopoietic progenitor cells. To clarify whether CD34 expression can be used to confirm the undifferentiated state of hematopoietic-like cells isolated from the bone marrow of bottlenose dolphin, Tursiops truncates, we determined in this study the sequence of dolphin CD34 cDNA and analyzed its mRNA expression. Dolphin CD34 cDNA can be expressed as two forms, one that encodes a full-length version and a variant, truncated version of the gene. Both forms were detected in bone marrow mononuclear cells and in various tissues using RT-PCR. The truncated form was not detected in peripheral blood mononuclear cells, and neither form was detected in polymorphonuclear leukocytes. This is the first report on CD34 in marine mammals and our results suggest that dolphin CD34 may be a useful marker to identify hematopoietic progenitor cells.  相似文献   
115.
This study aimed to investigate the ability of single nucleotide polymorphism (SNP) haplotypes in chicken mtDNA for presumption of the origins of chicken meat. We typed five SNPs of the D‐loop region in mtDNA by allele‐specific PCR (AS‐PCR) in 556 hens, that is 233 White Leghorn (WL), 50 Dekalb‐TX35 (D‐TX), 140 Barred Plymouth Rock (BPR) and 133 Rhode Island Red (RIR) kept in the National Institute of Livestock and Grassland Science (NILGS, Tsukuba, Japan). Five haplotypes were observed among those chickens by AS‐PCR. WL, D‐TX, BPR and RIR displayed three, two, one and four SNP haplotypes, respectively. By a combination of the haplotypes by AS‐PCR and the breeds, these chickens were classified into 10 groups. After the D‐loop was sequenced in two chickens from every group (20 individuals), 15 SNP sites (including one insertion) and eight sequence haplotypes were observed. In conclusion, haplotype variation was observed in and among the layer breeds of the NILGS. This study demonstrates that SNP haplotypes in mtDNA should be appropriate for the presumption of the origins of chicken meat.  相似文献   
116.
117.
The structure and tree species diversity of a subtropical evergreen broad-leaved forest in northern Okinawa Island, Japan, were studied. Enumeration of the six sampling plots revealed an average density of 5,580 individuals with DBH≧3.0 cm/ha, having an average basal area of 55 m2. The large-size trees of DBH≧20 cm contributed 10% of the total individuals, and 49% of the total basal area. The forest showed a high diversity of tree species, which is comparable to some tropical rain forests. A total of 54 over-story species of 24 families and a total of 63 understory species of 26 families were identified in the six sampling plots. Fagaceae and Theaceae were the most important families;Castanopsis sieboldii, Schima wallichii andDistylium racemosum were the most important species. The diversity index and equitability index of species were 4.15 and 0.72 for the overstory plots, and 4.72 and 0.79 for the understory subplots, respectively. The diversity index for the overstory was significantly correlated to the total basal area of trees over 20 cm DBH (p<0.05) and the importance value ofC. sieboldii (p<0.001), while for understory, the diversity index was not correlated to the structural parameters (allp>0.16). The size distribution pattern and age structure indicated differences in regeneration strategies for canopy dominants. In population dynamics of the succession process,C. sieboldii andD. racemosum were self-maintaining types, andS. wallichii was a gap- or opening-dependent type. This study was made possible by support from the Japanese Ministry of Education, Sciences, Sports and Culture, which provided a Monbusho scholarship to X.N. Xu.  相似文献   
118.
To investigate the potential effects of nitrogen (N) deposition on Japanese forests, a chronic N-addition experiment that included three treatments (HNO3, NH4NO3, and control) was carried out in a 20-year-old Japanese cedar (Cryptomeria japonica D. Don) stand in eastern Japan over 7 years. The amount of N applied was 168 kg N ha−1 year−1 on the HNO3 plots and 336 kg N ha−1 year−1 on the NH4NO3 plots. Tree growth, current needle N concentration, and soil solution chemistry were measured. Nitrogen application decreased the pH and increased NO3 , Ca2+, Mg2+, and Al concentrations in the soil solution. The needle N concentration increased in both of the N plots during the first 3 years. Nevertheless, the annual increments in height and in the diameter at breast height of the Japanese cedars were not affected by N application, and no visible signs of stress were detected in the crowns. Our results suggest that young Japanese cedar trees are not deleteriously affected by an excess N load.  相似文献   
119.
盐分再分配条件下河套灌区冲洗水量的数值模拟   总被引:7,自引:6,他引:7  
该文旨在探讨干旱缺水地区长期灌溉条件下,合理解决节水灌溉与冲洗灌溉间矛盾的途径,为在该地区实施节水灌溉战略提供理论依据。采用修正的对流扩散模型(SOTR)及特征有限元方法对中国内蒙古河套灌区冲洗—蒸发条件下的冲洗定额进行数值模拟研究。并用γ射线测定土柱土壤水盐运移结果标定了数值模拟结果。重点分析了基于土壤水动力学与溶质动力学原理,再灌溉冲洗与再分配条件下,均质垂直剖面上溶质运移过程;长期灌溉条件下,干旱地区土壤盐分布与冲洗定额、初始土壤盐分含量、地下水位埋深及地下水矿化度间的内在联系;在此基础上,确定节水灌溉条件下河套灌区最优的冲洗定额。该成果对于促进该地区农业可持续发展具有一定的指导意义  相似文献   
120.
Atherosclerosis is a vascular disorder involving inflammation, a narrowed vascular lumen in the entire tunica intima, and reduced elasticity of the arterial wall. It has been found that Hsp60 from Chlamydia pneumoniae, an obligate bacterial pathogen associated with atheroma lesions, mimics human Hsp60, thereby causing attacks by immune cells on stressed endothelial cells expressing endogenous Hsp60 on their surface. Furthermore, Hsp60 from C. pneumoniae has been shown to promote the growth of vascular smooth muscle cells (VSMCs). To explore probes that can be used for studying signal transduction elicited by the chlamydial Hsp60, we have tested several natural products for their inhibitory actions on the Hsp60-induced proliferation of rat arterial smooth muscle cells. Sesamol, vanillyl alcohol, and trans-ferulic acid exhibited moderate inhibitory actions on the Hsp60-induced cell proliferation; zerumbone, humulene, and caryophylene effectively inhibited it at low concentrations with IC(50) values of 529, 122, and 110 nM, respectively. The results indicated that the 11-membered alicyclic ring is favorable for interactions with receptors involved in the Hsp60-induced VSMC proliferation.  相似文献   
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