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991.
Asako Miyamoto Makoto Sano Hiroshi Tanaka Kaoru Niiyama 《Journal of Forest Research》2011,16(2):87-97
Land use and landscape changes, which have much effect on local biodiversity, are driven primarily by socioeconomic forces.
Understanding these forces is important for preservation of current biodiversity. In this study, we clarified the socioeconomic
forces that have brought about changes in the forest landscape around the Ogawa Forest Reserve in the southern Abukuma Mountains,
Japan, by interviewing local residents and reviewing local historical documents. Furthermore, we reconstructed past forest
landscapes and quantified the changes that have occurred from the beginning of the twentieth century until the present by
use of old land-use maps and past aerial photographs. The use of forest resources has dramatically changed during the past
hundred years, and it can be divided into three periods corresponding to the level of economic development. The main landscape
has changed significantly from one mainly composed of expansive grasslands and broad-leaved forests into a mosaic of fragmented
secondary forests and coniferous plantations. These landscape changes reflect shifts in both the use of forest resources by
local residents and the management of the national forests. Clarifying temporal–spatial landscape changes by understanding
the historical relationship between humans and the landscape provides useful information for optimizing conservation and management
planning. 相似文献
992.
Fragoulis G Merli A Reeves G Meregalli G Stenberg K Tanaka T Capri E 《Pest management science》2011,67(6):656-664
BACKGROUND: Quinoxyfen is a fungicide of the phenoxyquinoline class used to control powdery mildew, Uncinula necator (Schw.) Burr. Owing to its high persistence and strong sorption in soil, it could represent a risk for soil organisms if they are exposed at ecologically relevant concentrations. The objective of this paper is to predict the bioconcentration factors (BCFs) of quinoxyfen in earthworms, selected as a representative soil organism, and to assess the uncertainty in the estimation of this parameter. Three fields in each of four vineyards in southern and northern Italy were sampled over two successive years. RESULTS: The measured BCFs varied over time, possibly owing to seasonal changes and the consequent changes in behaviour and ecology of earthworms. Quinoxyfen did not accumulate in soil, as the mean soil concentrations at the end of the 2 year monitoring period ranged from 9.16 to 16.0 µg kg?1 dw for the Verona province and from 23.9 to 37.5 µg kg?1 dw for the Taranto province, with up to eight applications per season. To assess the uncertainty of the BCF in earthworms, a probabilistic approach was used, firstly by building with weighted bootstrapping techniques a generic probabilistic density function (PDF) accounting for variability and incompleteness of knowledge. The generic PDF was then used to derive prior distribution functions, which, by application of Bayes' theorem, were updated with the new measurements and a posterior distribution was finally created. CONCLUSION: The study is a good example of probabilistic risk assessment. The means of mean and SD posterior estimates of log BCFworm (2.06, 0.91) are the ‘best estimate values’. Further risk assessment of quinoxyfen and other phenoxyquinoline fungicides and realistic representative scenarios for modelling exercises required for future authorization and post‐authorization requirements can now use this value as input. Copyright © 2011 Society of Chemical Industry 相似文献
993.
Karasawa K Tanaka A Jung K Matsuda A Okamoto N Oida K Ohmori K Matsuda H 《Veterinary journal (London, England : 1997)》2011,190(2):e72-e77
Aquaporins (AQPs) function as water channels in many types of cells involved in fluid transport. More than 10 isoforms have been identified, and these are differentially expressed in many types of mammalian cells in the body. Six AQPs (AQP0, AQP1, AQP3, AQP4, AQP5, and AQP9) have been identified in the eyes of humans and/or rodents. The unique permeability characteristics and distribution of AQPs indicate their diverse roles in the regulation of water homeostasis in the eye. The aim of this study was to investigate the localisation of AQPs in normal canine eyes, with AQP0 protein expressed in the crystalline lens and retina. Although AQP1 mRNA was detected in various areas of the canine eye, its protein expression was limited to the cornea, iris and ciliary body. AQP4 was identified in the iris, retina and optic nerve. AQP3 and AQP5 were found in the cornea and conjunctiva, and their expression was particularly high in the limbus. AQP3 and AQP5 were present in the nictitating membrane indicating that they play a role in water transport within the membrane. The observations suggested that several subtypes of the AQP family are involved in the regulation of water homeostasis in the canine eye. 相似文献
994.
Hayashi A Tanaka H Kitamura M Nishida H Shimoda T Ohashi F Nakayama M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(3):419-422
A two-year-old dog having presented with neurological signs showed marked leukocytosis and appearance of blast cells in the peripheral blood. Hematological and bone marrow examination showed an increase in blasts having both myeloid and monocytic cells characteristics. The dog was diagnosed with acute myelomonocytic leukemia (AML-M4) on the basis of bone marrow findings. Although the dog was treated with a multi-combination chemotherapy, the neurological abnormalities progressed and the dog was euthanized. Myelographic examination and necropsy revealed the extradural lesion formed by AML-M4 around the cervical spinal cord and this lesion was considered as a cause of the neurological signs. 相似文献
995.
Nishino K Hattori N Sato S Arai Y Tanaka S Nagy A Shiota K 《The Journal of reproduction and development》2011,57(5):586-593
The Sry (sex determining region on Y chromosome) gene is a master gene for sex determination. We previously reported that the Sry gene has tissue-dependent and differentially methylated regions (T-DMRs) by analyzing the DNA methylation states at CpG sites in the promoter regions. In this study, we found unique non-CpG methylation at the internal cytosine in the 5'-CCTGG-3' pentanucleotide sequence in the Sry T-DMR. This non-CpG methylation was detected in four mouse strains (ICR, BALB/c, DBA2 and C3H), but not in two strains (C57BL/6 and 129S1), suggesting that the CCTGG methylation is tentative and unstable. Interestingly, this CCTGG methylation was associated with demethylation of the CpG sites in the Sry T-DMR in the developmental process. A methylation-mediated promoter assay showed that the CCTGG methylation promotes gene expression. Our finding shows that non-CpG methylation has unique characteristic and is still conserved in mammals. 相似文献
996.
Evaluation of the renin-angiotensin system in cardiac tissues of cats with pressure-overload cardiac hypertrophy 总被引:2,自引:0,他引:2
Uechi M Tanaka Y Aramaki Y Hori Y Ishikawa Y Ebisawa T Yamano S 《American journal of veterinary research》2008,69(3):343-348
OBJECTIVE: To clarify regulation of the renin-angiotensin (RA) system in cardiac tissues by measuring angiotensin-converting enzyme (ACE) and chymase activities in cats with pressure-overload cardiac hypertrophy. ANIMALS: 13 adult cats. PROCEDURES: Pressure-overload cardiac hypertrophy was induced by coarctation of the base of the ascending aorta in 6 cats, and 7 cats served as untreated control animals. Cats were examined before and 3 months and 2 years after surgery. Two years after surgery, cardiac hypertrophy was confirmed by echocardiography, and the blood pressure gradient was measured at the site of constriction. Cats were euthanized, and ACE and chymase activities were measured in cardiac tissues. RESULTS: Mean +/- SD pressure gradient across the aortic constriction was 63 +/- 6 mm Hg. Chymase activity predominated (75% to 85%) in the RA system of the cardiac tissues of cats. Fibrosis in the wall of the left ventricle was detected in cats with hypertrophy, and fibrosis of the papillary muscle was particularly evident. CONCLUSIONS AND CLINICAL RELEVANCE: Chronic pressure overload on the heart of cats can activate the RA system in cardiac tissues. A local increase in angiotensin II was one of the factors that sustained myocardial remodeling. 相似文献
997.
Tanaka Y Mori A Tazaki H Imai S Shiina J Kusaba A Ozawa T Yoshida T Kimura N Hayashi T Kenyon PR Blair H Arai T 《Research in veterinary science》2008,85(1):17-21
Plasma metabolite concentrations and activities of enzymes related to energy metabolism in plasma, peripheral leukocytes and liver of pregnant Romney ewes with restricted feeding were measured to assess those metabolites and enzymes as indicators for evaluating metabolic conditions in the ewes. The body weights and plasma lactate concentrations of the low-feeding ewes (about 1.0 times maintenance) were significantly lower than those of the high-feeding ewes (about 1.5 times maintenance). There were no significant differences in plasma protein, glucose, triglyceride, cholesterol, pyruvate and immunoreactive insulin concentrations and plasma and leukocyte enzyme activities between both groups. Hepatic malate dehydrogenase activities were significantly higher and hexokinase activities were significantly lower in the low-feeding ewes than in the high-feeding ewes. Restricted feeding could maintain pregnancy and some plasma metabolites and peripheral leukocyte enzymes may be useful indicators for evaluating metabolic changes in ewes. 相似文献
998.
Nine of 250 cows on a dairy farm initially developed severe dermatitis on parts of their bodies that touched the floor, and it then spread over their entire body. The cause was suspected to be calcium cyanamide, which had been added to the material spread on the floor to prevent environmental mastitis. Experimental exposure of the skin of a cow to calcium cyanamide induced the same type of contact dermatitis, and histopathological investigations showed that it caused irritant and allergic reactions. To identify the cause of the dermatitis, a patch test with calcium cyanamide and its breakdown products, cyanamide, urea and ammonium bicarbonate, was carried out on four cows. Three of them had a positive reaction to calcium cyanamide and cyanamide; delayed and amplified reactions suggesting an allergic response were observed. 相似文献
999.
Mori A Kenyon PR Mori N Yamamoto I Tanaka Y Suzuki N Tazaki H Ozawa T Hayashi T Hickson RE Morris ST Blair H Arai T 《Veterinary research communications》2008,32(2):159-166
Metabolite and immunoreactive insulin (IRI) concentrations, energy metabolism related enzymes activities and peripheral blood
mononuclear cell (PBMC) populations were measured in blood of pregnant Angus heifers with differing liveweight change profiles
(gaining or losing), in New Zealand to investigate the meanings of those parameters in the restricted feeding beef heifers.
Beef heifers losing liveweight (−412 g/day) showed significantly lower concentrations of plasma IRI, and higher concentrations
of plasma free fatty acid (FFA) than heifers gaining liveweight (483 g/day). The cytosolic and mitochondrial malate dehydrogenase
(MDH) activities and MDH/lactate dehydrogenase (M/L) ratio in leukocytes of the liveweight losing heifers were significantly
higher than those the liveweight gaining heifers. Percentages of cluster of differentiation (CD) 3 positive cells and natural
killer (NK) cells in PBMC decreased significantly in the liveweight losing heifers compared to those in the liveweight gaining
heifers. Plasma IRI and FFA concentrations, leukocyte cytosolic and mitochondrial MDH activities and CD3 positive and NK cell
populations may be useful markers to evaluate metabolic conditions and immunity in the restricted feeding beef heifers. 相似文献
1000.
Seijirow Goya Tomoki Wada Kazumi Shimada Daiki Hirao Ryou Tanaka 《Veterinary anaesthesia and analgesia》2018,45(4):432-442