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91.
Despite an improving regulatory framework and policies governing compensation and resettlement, the majority of the millions displaced worldwide each year by hydropower dam construction continue to experience marginalisation and impoverishment, suggesting that external financial support must be supplemented by strengthened community‐based resilience. In order to understand more about the innate resources of displaced rural communities, we applied a community resilience approach to two resettled Co‐tu ethnic minority villages in an upland area in central Vietnam to identify their community capitals and their application in improving livelihoods and living conditions. We found that weak human and financial capital constrained the ability of the resettled residents to adopt new livelihoods or migrate to seek employment. Reduced forest and river access also problematised responses to a lack of agricultural land. However, traditionally strong village affinity and social networks were retained. In addition, indigenous skills such as housing construction, honed by a highly mobile traditional lifestyle, allowed residents to construct culturally significant structures like community houses and modify or augment received housing stock. These elements of social and cultural capital eased the process of post‐resettlement adaptation. We conclude that governments should reassess current resettlement policies that prioritise financial compensation and should incorporate awareness of the adaptive resilience and limitations fostered by indigenous knowledge and practices in resettlement action plans.  相似文献   
92.
Intrathecal (IT) immunization involves injecting antigens directly into the intraventricular or subarachnoid spaces, or brain, to induce antigen-specific antibodies (Ab) in the cerebrospinal fluid (CSF). In the present study, rabbits were immunized IT with inactivated rabies virus to investigate the origins of CSF Ab. The time course of Ab induction and tumor necrosis factor-alpha expression suggested the possibility that the CSF Ab originated in the serum. In addition, Ab-producing cells infiltrated around the blood vessels of the brain, suggesting local production of Ab within the central nervous system (CNS). Furthermore, subcutaneous (SC) immunization prior to IT immunization induced a rapid and magnified Ab response in the CSF compared with IT immunization alone. These results were confirmed by the fact that mice immunized SC prior to IT were more resistant to intracerebral challenge with rabies virus than mice immunized via the IT route alone. Taken together, these results suggest that combined SC and IT immunization is a more effective vaccination protocol for prophylaxis and treatment of rabies.  相似文献   
93.
ABSTRACT: Group A rotaviruses (GARs) are one of the most common causes of diarrhea in suckling pigs. Although a number of G and P genotypes have been identified in porcine GARs, few attempts have been made to study the molecular epidemiology of these viruses associated with diarrhea outbreaks within a farm over an extended period of time. Here, we investigated the molecular characteristics of GARs that caused four outbreaks of diarrhea among suckling pigs in a farrow-to-finish farm over the course of a year. G and P genotyping of GARs detected at each outbreak demonstrated genetic diversity in this farm as follows: G9P[23] was detected at the first outbreak, G9P[13]/[22] and G9P[23] at the second, G3P[7] at the third, and G9P[23], G5P[13]/[22], and P[7] combined with an untypeable G genotype at the fourth. Sequence analysis of the detected GARs revealed that such genetic diversity could have resulted not only from the introduction of new GAR strains, but also from gene reassortment between GAR strains within the farm. Further, the GAR strain carrying the untypeable G genotype was shown to be a novel porcine GAR bearing a new G26 genotype, as confirmed by the Rotavirus Classification Working Group.  相似文献   
94.
Seven rabbits experimentally infected with rabbit haemorrhagic disease virus were examined haematologically and histologically. Haematologically, activated partial thromboplastin time and prothrombin time were markedly prolonged in the terminal phase of the disease, just prior to death (all the animals died between 27 and 40 hr after inoculation with rabbit haemorrhagic disease virus). There was an increase in the titre of fibrin degradation products and a decrease in antithrombin III activity during the same interval. Acute necrotic hepatitis and disseminated intravascular coagulation (DIC) in many organs, including the lung, kidney, spleen and heart were the characteristic histopathological changes. Thus, the haematological and histological changes suggested that DIC was induced by rabbit haemorrhagic disease virus infection. Severe liver necrosis was considered to be a factor causing DIC by inducing a hypercoagulable condition in the systemic blood circulation.  相似文献   
95.
Mitsuyoshi  Takiguchi  BVSc  MS  Jun  Yasuda  DVM  PhD  Kenji  Ochiai  DVM  PhD  Yutaka  Morita  DVM  Akira  Hashimoto  DVM  PhD 《Veterinary radiology & ultrasound》1997,38(5):398-399
A three-year-old, intact male, Siberian husky was evaluated for a two day history of dysuria. Sonographically there was an anechoic cyst-like structure in the urinary bladder. The abnormality appeared to be a'cyst within a cyst', which is a characteristic ultrasonographic feature of ureterocele in humans. Ultrasonography may be a useful means of establishing a diagnosis of ureterocele in dogs.  相似文献   
96.
97.
Effects of growth factors on development of fetal islet B-cells in vitro   总被引:1,自引:0,他引:1  
To investigate the role of growth factors (epidermal growth factor [EGF], betacellulin, and activin A) in the development of islet B cells of rat fetal pancreatic explants in vitro, pancreases from rat fetuses at day 18 of gestation were cultured for 96 hr, with or without these growth factors. Culture medium was changed every 24 hr, and the level of insulin released in the culture medium was measured. After 72 hr of culture, pancreases were examined histologically. As a result, EGF promoted cell proliferation, but reduced B cell volume. Whereas, betacellulin and activin A inhibited cell division, but promoted increased B cell volume and insulin secretion, especially activin A, which stimulated insulin release in a time dependent manner. These results suggest that EGF, betacellulin, and activin A promote pancreatic cell proliferation, islet B-cell differentiation, and islet B-cell differentiation and functional maturation, respectively, and that EGF, betacellulin, and activin A, in this order, regulate islet B-cell neogenesis.  相似文献   
98.
Infectious bursal disease (IBD) is characterized by immunosuppression due to the depletion of lymphocytes in the atrophied bursa of Fabricius (BF). We have sometimes encountered contradictory findings: chickens infected with the vaccine IBD virus (IBDV) strain have sometimes exhibited a highly atrophied BF, but not immunosuppression. In this study, chickens administered vaccine or wild-type strains of IBDV were later vaccinated with the B1 strain of the Newcastle disease virus (NDV). Bursal changes were examined histologically with a focus on the bursal follicle. The immunoreactivity to NDV was also evaluated with the hemagglutination inhibition test. In gross examination, we observed a few chickens with a severely atrophied BF in vaccine strain-administered groups (vaccine groups), and the level of severity was the same as that in the wild-type strain-administered group (wild-type group). However, these chickens retained humoral antibody responses to NDV and were revealed to possess a higher number of bursal follicles than those of the wild-type group. These results indicated that macroscopic evaluation dose not accurately reflect the immunoreactivity and degree of bursal damage in IBDV-administered chickens. We also found non-immunosuppressed chickens in the wild-type group. These non-immunosuppressed chickens retained a significantly higher number of normal follicles and total follicles according to our statistical analysis. Furthermore, a high correlation coefficient between the NDV-HI titer and the number of normal follicles was found in the wild-type group. These results implied that the retained number of normal follicles is important for the immunoreactivity of chickens infected with IBDV.  相似文献   
99.
Effects of goat manure application combined with charcoal and tannins, added as feed additives or mixed directly, on microbial biomass, microbial residues and soil organic matter were tested in a 2-year field trial on a sandy soil under Omani irrigated subtropical conditions. Soil microbial biomass C revealed the fastest response to manure application, followed by microbial residue C, estimated on the basis of fungal glucosamine and bacterial muramic acid, and finally soil organic C (SOC), showing the slowest, but still significant response. At the end of the trial, microbial biomass C reached 220 μg g?1 soil, i.e. contents similar to sandy soils in temperate humid climate, and showed a relatively high contribution of saprotrophic fungi, as indicated by an average ergosterol to microbial biomass C ratio of 0.35 % in the manure treatments. The mean fungal C to bacterial C ratio was 0.55, indicating bacterial dominance of microbial residues. This fraction contributed relatively low concentrations of between 20 and 35 % to SOC. Charcoal added to manure increased the SOC content and the soil C/N ratio, but did not affect any of the soil microbial properties analysed. Tannins added to manure reduce the 0.5 M K2SO4-extractable N to N total ratio compared to manure control. These effects occurred regardless of whether charcoal or tannins were supplied as feed additive or directly mixed to the manure.  相似文献   
100.
Many corals establish symbiosis with Symbiodiniaceae cells from surrounding environments, but very few Symbiodiniaceae cells exist in the water column. Given that the N-acetyl-d-glucosamine-binding lectin ActL attracts Symbiodiniaceae cells, we hypothesized that corals must attract Symbiodiniaceae cells using ActL to acquire them. Anti-ActL antibody inhibited acquisition of Symbiodiniaceae cells, and rearing seawater for juvenile Acropora tenuis contained ActL, suggesting that juvenile A. tenuis discharge ActL to attract these cells. Among eight Symbiodiniaceae cultured strains, ActL attracted NBRC102920 (Symbiodinium tridacnidorum) most strongly followed by CS-161 (Symbiodinium tridacnidorum), CCMP2556 (Durusdinium trenchii), and CCMP1633 (Breviolum sp.); however, it did not attract GTP-A6-Sy (Symbiodinium natans), CCMP421 (Effrenium voratum), FKM0207 (Fugacium sp.), and CS-156 (Fugacium sp.). Juvenile polyps of A. tenuis acquired limited Symbiodiniaceae cell strains, and the number of acquired Symbiodiniaceae cells in a polyp also differed from each other. The number of Symbiodiniaceae cells acquired by juvenile polyps of A. tenuis was correlated with the ActL chemotactic activity. Thus, ActL could be used to attract select Symbiodiniaceae cells and help Symbiodiniaceae cell acquisition in juvenile polyps of A. tenuis, facilitating establishment of symbiosis between A. tenuis and Symbiodiniaceae cells.  相似文献   
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