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71.
This paper describes an updated version of a screening tool for groundwater vulnerability assessment to evaluate pesticide leaching to groundwater, based on a revised version of the attenuation factor. The tool has been implemented in a geographical information system (GIS) covering the major islands of the state of Hawaii, USA. The Hawaii Department of Agriculture currently uses the tool in their pesticide evaluation process as a first-tier screening tool. The basic soil properties and pesticide properties necessary to compute the index, and estimates of their uncertainty, are included in the GIS. Uncertainties in soil and pesticide properties are accounted for using first-order uncertainty analysis. Classifications of pesticides as 'likely', 'uncertain' or 'unlikely' to leach are made on the basis of the uncertainty and a comparison of the revised attenuation factor with values and uncertainties of two reference chemicals. The reference chemicals represent what are considered to be a 'leachable' and a 'non-leachable' pesticide under Hawaii conditions. It is concluded that the tool is suitable for screening new and already used pesticides for the islands of Hawaii. However, the tool is associated with uncertainties that are not accounted for, so a conservative approach with respect to interpretation of the results and selection of pesticide parameters used in the tool is recommended.  相似文献   
72.
73.
We isolated endophytic fungi from living healthy leaves, petioles, and current-year twigs of Ginkgo biloba L. from April to November 2004 with the objective of identifying the dominant endophytic fungal taxa, and monitoring their occurrence and frequency. A total of 9 fungal taxa were identified to the genus level. Diversity measures inferred from the Shannon–Wiener, Morisita–Horn, and S?rensen indices indicated that leaves and petioles harbored more diverse endophytic fungal assemblages than twigs, and that fungal taxa involved in twigs shared less with those in leaves and petioles. Among the organs, the occurrence pattern of overall endophytic fungi differed significantly, and two taxa, Phomopsis sp. and Phyllosticta sp., were the most frequently isolated and thus regarded as the dominant endophytic fungi. Phomopsis sp. was isolated frequently from twigs (84.8%) but rather few from leaves (16.1%) and petioles (24.3%). Phyllosticta sp. was isolated frequently from leaves (72.9%) and petioles (65.7%) but was never isolated from twigs. Temporal changes in relative frequency of total endophytic fungi tended to differ among sampling dates for all three organs. The occurrence of Phyllosticta sp. in both leaves and petioles was first detected in August and peaked in October. Phomopsis sp. was detected in twigs throughout the growing season. These results suggest that the distribution of the two dominant endophytic fungi was organ-specific and differed within seasons.  相似文献   
74.
The stomach of the Pacific white-sided dolphin is divided into three parts: forestomach, proper gastric gland portion, and pyloric chamber. The histological features of the dolphin stomach are similar to those of terrestrial mammal stomachs, although the distribution of glycoconjugates in mucosal cells of the dolphin stomach is unknown. To learn about glycoconjugates in cetacean gastric mucosa, the glycoconjugate distribution in the mucous epithelium of the Pacific white-sided dolphin was studied using 21 lectins. Among the lectins tested, GSL-I and DBA specifically labelled the superficial layer of the forestomach epithelium. GSL-I, SBA, RCA-I, VVA, GSL-II, DSL, LEL, STL, s-WGA, WGA, PNA, and Jacalin labelled the luminal surface of the chief cells in the proper gastric gland. GSL-I, SBA, RCA-I, DSL, LEL, STL, s-WGA, PNA, and LCA labelled tubular structures in the cytoplasm of parietal cells. The surface portion of the pits in the pyloric chamber strongly reacted with RCA-I, GSL-II, WGA, PNA, LCA, PHA-L, and UEA-I, whereas the neck portion reacted weakly. Although lining one tubular portion, individual secretory cells in the pyloric gland displayed a heterogeneous reaction. This is the first report on the lectin histochemistry of a cetacean stomach and reveals GSL-I and DBA as specific marker lectins for the cornified stratified squamous epithelium cells of the Pacific white-sided dolphin. The stomachs of cetaceans and terrestrial mammals have similar histological features and mucous glycoconjugate content.  相似文献   
75.
In a previous study, we have developed several chicken monoclonal antibodies (mAbs) against Eimeria acervulina (EA) in order to identify potential ligand molecules of Eimeria. One of these mAbs, 6D-12-G10, was found to recognize a conoid antigen of EA sporozoites and significantly inhibited the sporozoite invasions of host T lymphocytes in vitro. Furthermore, some of these chicken mAbs showed cross-reactivities with several different avian Eimeria spp. and the mAb 6D-12-G10 also demonstrated cross-reactivities with the tachyzoites of Neospora caninum and Toxoplasma gondii. Cryptosporidium spp. are coccidian parasites closely related to Eimeria spp., and especially C. parvum is an important cause of diarrhea in human and mammals. In the present study, to assess that the epitopes recognized by these chicken mAbs could exist on Cryptosporidium parasites, we examined the cross-reactivity of these mAbs with Cryptosporidium spp. using an indirect immunofluorescent assay (IFA) and Western blotting analyses. In IFA by chicken mAbs, the mAb 6D-12-G10 only showed a immunofluorescence staining at the apical end of sporozoites of C. parvum and C. muris, and merozoites of C. parvum. Western blotting analyses revealed that the mAb 6D-12-G10 reacted with the 48-kDa molecular weight band of C. parvum and C. muris oocyst antigens, 5D-11 reacted the 155 kDa of C. muris. Furthermore, these epitopes appeared to be periodate insensitive. These results indicate that the target antigen recognized by these chicken mAbs might have a shared epitope, which is present on the apical complex of apicomplexan parasites.  相似文献   
76.
We examined in vivo efficiency of a gelatin film sheet with epidermal growth factor (EGF) for a novel therapeutic device for cutaneous wound repair. NIH3T3 fibroblasts and PAM212 keratinocytes proliferated when the cells were incubated with the homogenate of EGF containing gelatin sheets, indicating that the gelatin sheet retained biologic activity of EGF in the process of sheet formation. To evaluate therapeutic effects, the EGF containing gelatin sheets or control sheets were applied onto partial-thickness skin wounds made on dorsa of hairless dogs. Wound closure in wounds treated with EGF containing gelatin sheets was accelerated when compared to that of wounds treated with control sheets, exhibiting earlier reepithelialization of the epidermis and highly regulated repair of extracellular matrix in the dermis. Therefore, we concluded that the gelatin film is a useful material to keep EGF stable and the EGF containing sheet has the ability to become an efficient therapeutic agent for superficial or deep partial-thickness wounds in the skin.  相似文献   
77.
Leaves of tomato and barley were inoculated with conidia of Blumeria graminis f. sp. hordei race 1 (R1) or Oidium neolycopersici (KTP-01) to observe cytological responses in search of resistance to powdery mildew. Both conidia formed appressoria at similar rates on tomato or barley leaves, indicating that no resistance was expressed during the prepenetration stage of these fungi. On R1-inoculated tomato leaves, appressoria penetrated the papillae, but subsequent haustorium formation was inhibited by hypersensitive necrosis in the invaded epidermal cells. On the other hand, KTP-01 (pathogenic to tomato leaves) successfully developed functional haustoria in epidermal cells to elongate secondary hyphae, although the hyphal elongation from some conidia was later suppressed by delayed hypersensitive necrosis in some haustorium-harboring epidermal cells. Thus, the present study indicated that the resistance of tomato to powdery mildew fungi was associated with a hypersensitive response in invaded epidermal cells but not the prevention of fungal penetration through host papilla.  相似文献   
78.
Conidiogenesis by Oidium neolycopersici KTP-01 on tomato leaves was vitally monitored with a high-fidelity digital microscope. Conidiophores were initially formed 3 days after inoculation and then elongated to a maximum length within at least 12h. The apical part was split into two cells after two successive septations, accompanied by apical expansion. These cells subsequently developed into primary and secondary conidia. An additional septation at the stem portion of the conidiophores produced a generative and a foot cell. Subsequent conidiation occurred during repeated cycles of splitting of the generative cell, maturation of the apical cell into a conidium, and abstriction of the conidium. To our knowledge, this report is the first on the developmental process of conidiogenesis by powdery mildew on host leaves as revealed with the digital microscope.  相似文献   
79.
It is well known that chicken B cells develop in the bursa of Fabricius (BF), which is categorized as gut-associated lymphoid tissue (GALT). Chicken GALT also includes Peyer's patch (PP) and cecal tonsil (CT). The relationship between these tissues in GALT during B cell development is currently unknown. In this study, we conducted comparative examination of PP, CT and BF development during embryogenesis using immunohistochemical staining. On day 13 of embryogenesis (E13), accumulation of MHC class II(+) cells was observed in the intestine. Thereafter, Bu-1(+) cells and IgM(+) cells appeared, and their number continuously increased at the same sites where MHC class II(+) cells were present. Similar results were obtained in the CT. The locations of embryonic PP were limited to two sites; near the Meckel's diverticulum and the ileocecal junction. Anlage of bursal follicles first appeared at E13 and developed thereafter. Immigration of Bu-1(+) cells to bursal follicles began at E13, and the number of Bu-1(+) cell subsequently increased. When the follicle of BF was eliminated from the embryo by treatment with testosterone, development of PP and CT were observed. We concluded therefore that the development of PP and CT start during late embryogenesis at the same time as the follicle of BF, and that appearance of surface IgM(+) cells in PP and CT is independent form the development of the follicle of BF.  相似文献   
80.
The infectivity of a Japanese isolate of tomato powdery mildew, Oidium neolycopersici KTP-01, to tomato cultivars was examined using a resistant cultivar Grace bred in The Netherlands to O. lycopersici, which was recently proposed to be renamed O. neolycopersici. Grace was severely infected with KTP-01, and its susceptibility was similar to that on susceptible tomato cultivars Moneymaker and Ponderosa, suggesting that KTP-01 differs in pathogenicity on tomatoes from those of European and American isolates.  相似文献   
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