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171.
Biogeochemical proton and base cation fluxes in a 30-year old white birch forest composed of Dystric Cambisols in northern Hokkaido, Japan were estimated using data on atmospheric deposition (AD), throughfall (TF), stemflow (SF), and discharge from soils (DS) and plant uptake (UP) from early June to November 1999. In the monitoring period, proton flux was 0.20kmolcha?1 for AD, 0.07 for TF+SF, and 0.03 for DS, indicating that atmospheric acid input was neutralized through plant and soil. Base cation flux was 1.29 for AD, 1.23 for TF+SF, and 0.99 for DS and plant base cation uptake was 2.14, indicating that the soil was the major source of base cation for plant. However, these seasonal fluxes showed various trends. Cumulative base cation flux in TF+SF showed constant increase trend during the whole period, which was similar to AD. Proton flux in AD jumped once just after a heavy rain of 255mm for 8 days at the end of July. Trends for the proton and base cation fluxes in TF plus SF were similar to that of AD. Although proton and base cation fluxes of DS were not found until middle July because of vegetation uptake and no flow, both fluxes increased suddenly after the heavy rain in July. After August, the base cation and proton fluxes in the DS increased continuously, due to the lack of plant uptake and intermittent rainfall. In this study, it is clear that plant activity and water flow are very important driving force for seasonal dynamics of biogeochemical cycling.  相似文献   
172.
Earthworms commonly dominate the soil fauna and they play important roles in terrestrial ecosystems, but their numbers decrease in acidic conditions. Their sensitivity to low pH was studied in Europe and their distributions were explained by their sensitivity. These kinds of studies have not been conducted in Japan. Sensitivity of a common Japanese earthworm, Allolobophora japonica, to acidified soils was studied. Worms withdrew its prostomium (oral organs) abruptly from Clark-Lubs buffer solutions of pH 3.9–4.1 when they were dipped into the solutions. The species did not burrow into soils of pH (H2O) < 3.6 and died on and in the soils of pH (H2O) < 4.0. It seemed that the species did not tolerate the soils of pH (H2O) < 4.0. The responses to acid soil were almost same as those of European species. Soils should be maintained above pH 4 for this species.  相似文献   
173.
Annual biogeochemical fluxes (bulk precipitation, throughfall, stem flow, soil solution and vegetation uptake) of inorganic elements were observed in eight cool temperature forested ecosystems in Hokkaido, northern Japan, in order to determine the mechanisms of acid neutralization in Japanese forest ecosystems. We compared our results with the other biogeochemical studies in Japan, north Europe and US from the literature. In many Japanese forests, the internal proton production (IPS) by base cation accumulation into the vegetation was a major proton source, rather than external acidic deposition, and the IPS also affected the base cation fluxes from the mineral. IPS in Japanese forest tended to be larger than that in north Europe and US. Our results suggested that the high acid neutralizing ability of Japanese forests could be attributed to the strong relationship between the base cation buffering of the soil and the larger contribution of IPS as a proton source. acidic deposition|biogeochemical cycling|forest ecosystem|Japan|proton budget  相似文献   
174.
A 27-year-old Arabian pony gelding presented for evaluation of weight loss, intermittent sheath oedema, persistent neutropenia and thrombocytopenia, and acute left hindlimb swelling and gait abnormality. Clinical findings included swelling, heat and sensitivity localised over the left greater trochanter, mild to moderate ventral and sheath oedema, a left hindlimb post-legged gait, and off-loading of weight from the left hindlimb at rest. Initially, neutropenia and thrombocytopenia were confirmed on bloodwork, but neutrophilia and thrombocytopenia persisted as the case progressed. Diagnostic imaging (radiography and percutaneous ultrasonography) of the left hindquarters revealed an aggressive, mixed proliferative and lytic bony lesion of the proximal left femur as well as associated muscle fibre disruption and a soft tissue mass. A percutaneous core biopsy of the lesion led to the diagnosis of osteoblastic osteosarcoma on histopathology. Pain and inflammation associated with the lesion was medically managed in the hospital with mild improvement. Additionally, palliative radiation was performed under general anaesthesia. Unfortunately, before a response to palliative radiation could be assessed, the patient was subjected to euthanasia due to development of acute neurological signs.  相似文献   
175.
An immunohistochemical and histopathological study using the ABC technique was carried out to examine time-sequential virus spread in the central nervous system (CNS) of mice after inoculation with the CVS strain of fixed rabies virus by different routes; intracerebral (ic), intraocular (io), intranasal (in), intramuscular (im) and subcutaneous (sc). Only the ic and io inoculations caused fatal infections, so that detailed analysis was conducted on mice inoculated by these two routes. In ic-inoculated mice, viral antigens were detected mainly in neurons in the cerebral cortex and in the pyramidal cells and granular cells of the hippocampus. After io inoculation, viral antigen was first detected in the trigeminal nerve ganglia, following which it spreads to the cerebral cortex and cerebellum. In the hippocampus only a few cells were viral antigen-positive at the early stage after io inoculation. There were no inflammatory lesions or Negri bodies in the CNS of mice infected by either route. This suggests that clinical signs such as ataxia or depression leading to death may be due to the direct effect of the virus on the functions of neural cells, but not to inflammatory reactions. The ABC method will be useful for the early diagnosis of suspected patients or animals to have the disease when conventional histopathological and immunofluorescent antibody techniques can not detect lesions or viral antigens.  相似文献   
176.
SUMMARY: The relationship between mean weights of hatchery-reared masu salmon Oncorhynchus masou smolts at release and the subsequent recovery rates by coastal commercial fisheries in Hokkaido, northern Japan, was investigated using the maximum likelihood method. A strongly positive correlation was observed, showing smolts with a mean of 32.6 g obtained an approximately 20-fold recovery rate of those with a mean of 14.8 g. The model with log-transformed independent variable ( Yi = –11.237 + 4.239 ln Xi ) was selected as the most parsimonious model to represent the release size ( Xi ) and recovery rate ( Yi ) relationship.  相似文献   
177.
178.
The dose of 2% chlorhexidine acetate (2CA; Nolvasan® Surgical Scrub; Fort Dodge Animal Health, Fort Dodge, IA, USA) for canine superficial pyoderma was evaluated. The first trial compared three doses (group 1, 57 mL/m2 body surface area; group 2, 29 mL/m2 body surface area; and group 3, 19 mL/m2 body surface area) in a randomized, double‐blind, controlled fashion. Twenty‐seven dogs with superficial pyoderma were treated with 2CA at the allocated doses every 2 days for 1 week. The owners and investigators subjectively evaluated the dogs, and investigators scored skin lesions, including erythema, papules/pustules, alopecia and scales, on a 0–4 scale. There were no significant differences in response between the treatment groups. The second trial established a practical dose‐measuring method for 2CA. Sixty‐eight owners were asked to apply 2CA on their palm in an amount corresponding to a Japanese ¥500 coin, 26.5 mm in diameter. This yielded an average dose of 0.90 ± 0.40 mL. Mathematically, the doses used in groups 1, 2 and 3 can be represented as one coin per approximately one‐, two‐ and three‐hand‐sized lesions, respectively. The results therefore suggest that owners instructed to apply one coin of the product per two‐hand‐sized areas of superficial pyoderma would use the range of doses evaluated in this trial.  相似文献   
179.
The aims of this study were to investigate the diversity of lactic acid bacteria (LAB) isolated from traditional Mongolian dairy products, and to estimate the probiotic potential of the isolated strains. We collected 66 samples of the traditional Mongolian dairy products tarag (n = 45), airag (n = 7), aaruul (n = 8), byasulag (n = 1) and eezgii (n = 5), from which 543 LAB strains were isolated and identified based on 16S ribosomal DNA sequence. The predominant species of those products were Lactobacillus (L.) delbrueckii ssp. bulgaricus, L. helveticus, L. fermentum, L. delbrueckii ssp. lactis and Lactococcus lactis ssp. lactis. However, we could not detect any LAB strains from eezgii. All LAB isolates were screened for tolerance to low pH and to bile acid, gas production from glucose, and adherence to Caco‐2 cells. In vitro, we found 10 strains possess probiotic properties, and almost identified them as L. plantarum or L. paracasei subspecies, based on 16S ribosomal DNA and carbohydrate fermentation pattern. These strains were differentiated from each other individually by randomly amplified polymorphic DNA analysis. Additionally, it was notable that 6/10 strains were isolated from camel milk tarag from the Dornogovi province.  相似文献   
180.
Effect of interferon-alpha 1 from E. coli on some cell functions   总被引:8,自引:0,他引:8  
Interferon-alpha 1 from Escherichia coli transformed with a hybrid plasmid containing a human leukocyte complementary DNA insert, induces resistance to virus in appropriate target cells. It also shares the following properties with natural leukocyte interferon (IFN). (i) It enhances natural killing activity of human lymphocytes, (ii) it enhances antibody-dependent cell-mediated cytotoxicity, (iii) it suppresses antigen- and mitogen-induced leukocyte migration inhibition, (iv) it inhibits growth of IFN-sensitive Burkitt lymphoma cells. Since these activities are exhibited by a cloned protein species, they are due to IFN itself and not to other human proteins.  相似文献   
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