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101.
102.
Hiroko AKIYAMA Atsushi HAYAKAWA Shigeto SUDO Seiichiro YONEMURA Takeshi TANONAKA Kazuyuki YAGI 《Soil Science and Plant Nutrition》2009,55(3):435-440
We describe an automated gas sampling system for monitoring trace gas fluxes from soils. The sampling system allows automated collection of gas samples in glass vials using a syringe pump connected to an automated static chamber installed in the field. The gas samples are transferred to a laboratory and then analyzed using a gas chromatography system. Comparisons between manual and automated sampling of standard gases showed good agreement ( r 2 = 0.99996 for N2 O, r 2 = 0.999 for CH4 and r 2 = 0.998 for CO2 ). In a field test, replicated flux measurements using two chambers generally showed good agreement. The sampling system allows frequent and long-term monitoring of fluxes under a wide range of weather conditions (tested temperatures ranged from –6.5 to 40°C; 127 mm day−1 max precipitation). The major advantages of the system are its increased portability, ease of operation and cost effectiveness compared with on-line automated sampling/analytical systems. 相似文献
103.
Yuichi SAEKI Hiroko OGURO Isao AKAGI Takeo YAMAKAWA Akihiro YAMAMOTO 《Soil Science and Plant Nutrition》2009,55(5):627-633
The soybean-nodulating Sinorhizobium fredii strain has been reported to possess three copies of rRNA gene operons. In the present study, we investigated the diversity of the 16S–23S rDNA internal transcribed spacer (ITS) regions of S. fredii strains. Based on the sequences of the ITS regions, we divided the sequences of the S. fredii strains into two groups, type A and type B. A dot-matrix analysis indicated that the region flanked by tRNA-Ile and tRNA-Ala is longer in type A than in type B, whereas type B sequences possess longer regions upstream of tRNA-Ile and downstream of tRNA-Ala than those of the type A sequence. Restriction fragment length polymorphism of polymerase chain reaction product (PCR-RFLP) of the ITS region in the cloned plasmids as templates could reconstruct the PCR-RFLP pattern from the total DNA as a template. The results of Southern hybridization using the insert sequence between tRNA-Ile and tRNA-Ala in type A as a probe indicated differences in the copy numbers of the type A ITS regions among the strains tested. These results indicated that S. fredii strains possess the type A and type B sequences of the ITS regions at ratios of 3:0, 2:1, 1:2 or 0:3. These S. fredii strains may be useful biological materials for the study of intraspecific variations. 相似文献
104.
Agricultural headwater ditches are an important source of indirect agricultural nitrous oxide (N2O) emissions, but their contribution is difficult to quantify. In the present study, the static chamber-gas chromatography technique was used for measurement of N2O emissions from vegetated (V, the whole ditch ecosystem) and non-vegetated (NV, the sediment-water interface only) zones in an agricultural headwater ditch in the Central Sichuan Basin in Southwestern China during 2014–2015. Annual N2O emissions from the agricultural headwater ditch were similar to direct N2O emissions from an adjacent N-fertilized purple soil cropland, suggesting nitrogen (N)-enriched ditches are important anthropogenic N2O sources. Mean cumulative N2O emissions during summer and autumn were higher than those in spring and winter. Overlying water nitrate (NO3 ?-N) concentration and sediment-water interface temperature were primary factors affecting seasonal N2O emissions. Heavy precipitation transported NO3 ?-N from cropland and increase NO3 ?-N in the agricultural headwater ditch water, and subsequently stimulate N2O emissions. A literature review of EF5r (the indirect N2O emission factor for rivers) revealed a mean value of 0.23%, similar to our values (0.27%), and also the default value (0.25%) proposed by the Intergovernmental Panel on Climate Change. The number of studies on indirect N2O emissions remains limited, and more in situ measurements are needed to have more accurate values of EF5r. 相似文献
105.
Jemai H Fki I Bouaziz M Bouallagui Z El Feki A Isoda H Sayadi S 《Journal of agricultural and food chemistry》2008,56(8):2630-2636
This study was designed to test the lipid-lowering and antioxidative activities of triacetylated hydroxytyrosol compared with its native compound, hydroxytyrosol, purified from olive tree leaves. Wistar rats fed a standard laboratory diet or a cholesterol-rich diet for 16 weeks were used. The serum lipid levels, the thiobarbituric acid-reactive substances (TBARS) level, as an indicator of lipid peroxidation, and the activity of superoxide dismutase (SOD) as well as that of catalase (CAT) were examined. The cholesterol-rich diet induced hypercholesterolemia that was manifested in the elevation of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C). Administration of hydroxytyrosol and triacetylated hydroxytyrosol (3 mg/kg of body weight) decreased the serum levels of TC, TG, and LDL-C significantly and increased the serum level of high-density lipoprotein cholesterol (HDL-C). Furthermore, the content of TBARS in liver, heart, kidney, and aorta decreased significantly when hydroxytyrosol and its triacetylated derivatives were orally administered to rats compared with those fed a cholesterol-rich diet. In addition, triacetylated hydroxytyrosol and hydroxytyrosol increased CAT and SOD activities in the liver. These results suggested that the hypolipidemic effect of triacetylated hydroxytyrosol and hydroxytyrosol might be due to their abilities to lower serum TC, TG, and LDL-C levels as well as to their antioxidant activities preventing the lipid peroxidation process. 相似文献
106.
Neurotropism of the 1997 Hong Kong H5N1 influenza virus in mice 总被引:12,自引:0,他引:12
Tanaka H Park CH Ninomiya A Ozaki H Takada A Umemura T Kida H 《Veterinary microbiology》2003,95(1-2):1-13
The direct transmission of H5N1 influenza A viruses from chickens to humans in Hong Kong in 1997 emphasized the need to have information on the pathogenesis of avian influenza virus infection in mammals. H5N1 influenza viruses isolated from patients during the incident killed experimentally infected mice. The principal lesions of the mice were broncho-interstitial pneumonia and nonsuppurative encephalitis. Infectious viruses and/or viral antigens were detected in the brain as well as in the trigeminal and vagal ganglia but not in the blood of the mice. These findings suggest that the virus reached the brain through the vagus and/or trigeminal nerves following replication in the respiratory mucosa. The results imply that neurotropism of the H5N1 virus in mice is a novel characteristic in the pathogenesis of infection by human influenza virus isolates. 相似文献
107.
Taniguchi K Obitsu T Ohmura H Hiraga A Hata H Aida H Akiyama K Tanaka K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):927-930
A rigid-type of polyethylene T-cannula was fitted into the anterior ileum of six horses in order to improve the cannulation techniques. A piece of polyethylene net was fastened onto the intestinal wall around the cannula to prevent dislodgment of the cannula by promoting a secure adhesion between the ileum and the abdominal wall. The cannula barrel sheathed with silicone tubing was exteriorized through a stab incision at the lateral ventral wall on the transverse line of the second lumber vertebra, and a flange was screwed onto the barrel. The feeding regime gradually increased concentrate without roughage prevented any colic signs. The use of these techniques succeeded in the ileal cannulation with no leakage of digesta. 相似文献
108.
109.
Kazunori Kuwata Itsuko Nakamura Mika Ide Hiroko Sato Satomi Nishikawa Masaharu Tanaka 《Journal of toxicologic pathology》2015,28(3):151-164
To investigate useful biomarkers associated with proximal tubular injury, we assessed
changes in levels of a focused set of biomarkers in urine and blood. Male rats
administered a single dose or four doses of gentamicin (GM, 240 mg/kg/day) or a single
dose of cisplatin (CDDP, 5 mg/kg) were euthanized on days 2 (the day after initial dosing)
5, or 12. At each time point, histopathological examination of the kidney and
immunohistochemistry for biomarkers, kidney injury molecule-1 (Kim-1), lipocalin (NGAL),
clusterin (CLU), cystatin C (CysC) and β2-microglobulin (β2M) were performed. Biomarker
levels were measured in urine and blood. In both treatment groups, degenerated/necrotic
proximal tubules and regenerated tubules were mainly observed on days 5 and 12,
respectively. At the same time as these tubular injuries, urinary Kim-1, CysC and β2M
levels were increased. Moreover, urinary levels of CysC and β2M in GM-treated animals and
Kim-1 in CDDP-treated animals increased (on day 2) prior to tubular injury on day 5. This
was considered to reflect the characteristics of drug toxicity. Although almost all of the
biomarkers in blood were not sufficiently sensitive to detect proximal tubular injury,
urinary and plasma β2M levels simultaneously increased. Therefore, in addition to urinary
Kim-1, CysC and β2M levels, plasma β2M levels were also considered useful for detecting
proximal tubular injury. 相似文献
110.
Prayuth SAEKHOW Shingo KISHIZUKA Natsuha SANO Hiroko MITSUI Hajime AKASAKI Takahiro MAWATARI Hidetoshi IKEDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1581-1586
The infection status of 15 viruses in 120 pigs aged about 6 months was investigated based
on tonsil specimens collected from a slaughterhouse. Only 5 species of porcine
parvoviruses and porcine circovirus type 2 (PCV2) were detected at high frequencies; 67%
for porcine parvovirus (PPV) (PPV-Kr or -NADL2 as the new abbreviation), 58% for PPV2
(CnP-PARV4), 39% for PPV3 (P-PARV4), 33% for PPV4 (PPV4), 55% for PBo-likeV (PBoV7) and
80% for PCV2. A phylogenetic analysis of PPV3 suggested that Japanese PPV3s showed a
slight variation, and possibly, there were farms harboring homogeneous or heterogeneous
PPV3s. Statistical analyses indicated that the detection of PCV2 was significantly
coincidental with each detection of PPV, PPV2 and PPV3, and PPV and PPV4 were also
coincidentally detected. The concurrent infection with PCV2 and porcine parvoviruses in
the subclinically infected pigs may resemble the infection status of pigs with the
clinical manifestations of porcine circovirus associated disease which occurs in 3–5
months old pigs and is thought to be primarily caused by the PCV2 infection. 相似文献