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221.
Hiroshi SUNAHARA Yoko FUJII Keisuke SUGIMOTO Takuma AOKI Gou SUGAHARA Kinji SHIROTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):95-99
A two-month-old female Chihuahua was diagnosed as severe pulmonary valvular
stenosis (PS). Although balloon valvuloplasty (BV) was successfully performed, restenosis
was observed 19 months after the procedure. Euthanasia was chosen due to low output
syndrome during the surgical repair attempted when the dog was 5 years old. Postmortem
examination revealed markedly thickened pulmonary valve due to the increase of
extracellular matrix which might be produced by increased α smooth muscle actin-positive
myofibroblasts. The thickening of the valve was associated with restriction of the valve’s
motion, resulting in restenosis in the present case. This is the first case report
documented histopathological and immunohistochemical findings of the restenotic pulmonary
valve in dogs with PS after BV. 相似文献
222.
Soil N transformation was investigated using15N dilution method along a slope on a conifer plantation forest. Although there was no significant difference in the net N
mineralization rates by laboratory incubation, net nitrification rates increased downslope. Gross N transformation by15N dilution method showed a distinct difference not only on the rates, but also on the main process between the lower and the
upper of the slope. Half of minelarized N was immobilized and the other half was left in NH
4
+
pool at the upper part of the slope, while all of mineralized N was used for immobilization or nitrification and NH
4
+
pool decreased at the lower of the slope. Soil N transformations were classified into two groups: one was shown below 773
m and the other was shown above 782 m. The incubation with nitrification inhibitor showed that nitrification was mainly conducted
by autotrophs irrespective of the position of the slope. Microbial biomass and microbial C/N were similar among the sites.
However, the gross mineralization rate was higher below 773 m than above 782 m under similar respiration rates. This suggests
that the substrate quality may be one of the controlling factors for soil N transformation. Extractable organic C/N was similar
to microbial C/N at the lower of the slope. It indicated that the substrate was more decomposable below 773 m. It is considered
that soil N transformation is affected by topographical gradient of moisture and nutrient which makes plant growth and decomposition
rate different. 相似文献
223.
224.
Influence of heating history on dynamic viscoelastic properties and dimensions of dry wood 总被引:2,自引:2,他引:0
To obtain new information about the mechanical and physical properties of dry wood in unstable states, the influence of heating
history on viscoelastic properties and dimensional changes of dry wood in the radial, tangential, and longitudinal directions
was studied between 100° and 200°C. Unstable states of dry wood still existed after heating at 105°C for 30 min and were modified
by activated molecular motion in the first heating process to temperatures above 105°C. This phenomenon is thought to be caused
by the unstable states reappearing after wetting and drying again. Dry wood components did not completely approach the stable
state in the temperature range tested, because they did not entirely surpass the glass transition temperatures in most of
the temperature range. In constant temperature processes at 135° and 165°C, E′ increased and E″ decreased with time regardless of the direction. This indicated that the unstable states of dry wood components were gradually
modified with time at constant temperatures. On the other hand, anisotropy of dimensional change existed and dimension increased
in the longitudinal direction, was unchanged in the radial direction, and decreased in the tangential direction with time
at constant temperatures.
Part of this report was presented at the 13th Annual Meeting of the Chubu Branch of the Japan Wood Research Society, Shizuoka,
August 2003 相似文献
225.
Yusuke TANAKA Keisuke SUGANUMA Kenichi WATANABE Yoshiyasu KOBAYASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(8):1212
Dourine, caused by infection with Trypanosoma equiperdum, is one of the trypanosomiasis in equids. The clinical course of dourine is long-term, ranging from 1–2 months to several years. Since the pathogenesis of dourine has not yet been elucidated, experimental studies using mouse infection models are needed. Although mice are not susceptible to most T. equiperdum strains, some strains can infect mice. Even in such strains, infected mice develop rapidly transient parasitemia and die within 2–8 days. Therefore, mice experimentally infected with these T. equiperdum strains are not suitable for mouse infection models to analysis the pathogenesis of dourine. A sequential method of isolating parasites from dourine-affected horses and adapting them to in vitro cultures using soft agarose media was recently developed. Various T. equiperdum strains adapted to in vitro conditions have been established using this technique. We used one of these strains, the T. equiperdum IVM-t2 strain. In the present study, T. equiperdum IVM-t2 strain inoculated mice developed periodic parasitemia during the experimental period of 60 days. Histopathologically, vaginitis and dermatitis were observed. These findings were comparable to those of dourine-affected horses. Therefore, mice infected with T. equiperdum IVM-t2 strain may be a valuable tool for pathological, immunological, and parasitological in vivo research, and will contribute to investigations on the mechanisms underlying the disease process and the host-parasite relationship. 相似文献
226.
Samet Can Söylemez Keisuke Murakami Carlos Augusto Strüssmann Masashi Yokota Seiichi Watanabe 《Fisheries Science》2010,76(3):437-444
This study examined the ability of late stage (instar XXVI) Japanese spiny lobster Panulirus japonicus phyllosoma larvae to uptake seven l-type amino acids (AAs; aspartic acid, Asp; threonine, Thr; glutamic acid, Glu; glycine, Gly; alanine, Ala; valine, Val; and
methionine, Met) from the rearing medium. The time course uptake during incubation for 5 h in solutions containing 1, 2, 5,
10, or 20 μM of each AA was determined using high performance liquid chromatography. There was considerable individual variation
in uptake rates and even occasional release of AAs, but larvae showed net uptakes of all seven AAs. Two polar acidic AAs (Glu
and Asp) were readily taken up whereas neutral AAs, including three considered as essential for crustaceans (Val, Met, and
Thr), had lower uptake rates. Transient releases of AAs by the larvae were common for the AAs with the lowest uptake rates
at 1–2 h of incubation. Uptake rates increased with increasing AA concentration but less so for those taken up in larger amounts.
Larvae took up AAs to a total of 16.4 μmol/g/h for incubation in the 20 μM solution. The ability to uptake nutrients directly
from the medium may be important for the well-being of the larvae. 相似文献
227.
The neuropeptide cubifrin-I and its derivative cubifrin-L have recently been shown to be potent substances that induce in
vitro oocyte maturation and spawning in the Japanese common sea cucumber Apostichopus japonicus. We have examined the reproductive behavior of A. japonicus in vivo following the injection of cubifrin-L into the body cavity with the aim of determining the practical value of using
this peptide to induce spawning in the hatchery setting. The responsiveness of ovarian fragments with oocytes >155 μm in diameter
to cubifrin-L in vitro was well correlated with the spawning success induced in vivo by a cubifrin-L injection. Mature sea
cucumbers injected with cubifrin-L displayed sequential reproductive behaviors, which comprised climbing up the side wall
of the tank toward the water surface, waving of the head, and shedding of gametes. Gamete shedding started about 60 and 80 min
after the injection of cubifrin-L in males and females, respectively, and was completed almost simultaneously in the two sexes
about 2 h post-injection. Repeated injections of cubifrin-L at intervals of about 10 days successfully induced multiple spawnings
in males and females. These results demonstrate that cubifrin-L can be used as an effective inducer of spawning in Japanese
sea cucumber cultivation. 相似文献
228.
229.
[目的]采取淋洗、冲洗或两者并用措施,对恰布拉村牧民定居点盐碱土壤进行改良,为改良盐碱化土壤,提高现有土地生产能力提供科学依据.[方法]分别在排碱渠临界条田20、40、60和80 m处采取0~80cm土样(20 cm为1层)测定其土壤电导率变化(试验1).对盐碱化土壤进行冲洗(A区)、淋洗(B区)或两者并用(AB区)处理和对照区(CK区),测定0~80 cm处(10 cm为1层)土壤电导率、阳离子含量变化,与对照区进行比较分析(试验2).[结果]排碱渠的排盐碱有效距离为0~40 m;B区的电导率ECe值每一层基本都在11~12 ms/cm,与A区相比表层土ECe值明显降低;50 cm以下的土壤ECe值变化幅度各处理间差异不大.0~50 cm土壤的pH值变化无规则,但下层土壤pH值均呈下降趋势,其顺序为B、AB、A、CK.A区表层土Na+含量降低,但下层土壤中含量比A、AB和CK区高,表明盐碱溶解后被冲至下层.[结论]淋洗对盐碱土壤改良的效果最佳,降低了土壤电导率和Na+含量. 相似文献
230.
采用CCN6000水稻叶片氮素快速测定仪,以籼型常规早稻中早39为材料,研究了水稻叶片氮含量化学分析值、CCN值及SPAD值的关系。结果表明,早稻倒1叶叶片CCN值与含氮量呈近1.0∶1.0的关系,倒2叶叶片CCN值与含氮量呈近1.0∶1.1的关系,倒3叶叶片CCN值与含氮量呈近1.0∶1.2的关系,倒1叶CCN值与含氮量之间最为吻合,CCN值与SPAD值显著相关。水稻孕穗期叶片含氮量为倒3叶倒2叶倒1叶。研究表明,CCN值可以作为叶片含氮量的快速诊断依据。 相似文献