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111.
112.
We report that in a leaf insect, Phyllium westwoodii Wood-Mason (Phasmatodea: Phylliidae), two differing apertures can be used for oviposition, the color of eggs being affected by which aperture is used. Eggs which are forcibly propelled from the internal space within the valvulae of the abdomen are brown, whereas white eggs emerge slowly from the opening between the eighth sternite and the valvulae, and are deposited close to the ventral surface of the female. This unusual oviposition system does not appear to have been previously reported in phasmatids or in other insects. 相似文献
113.
Field measurement of infiltration rate using an oscillating nozzle rainfall simulator in the cold, semiarid grassland of Mongolia 总被引:2,自引:0,他引:2
Recent intensive grazing in Mongolia may be significantly reducing the infiltration rate of rangeland. This study measured infiltration rates using simulated rainfall with high raindrop impact for small plots established on steppe grassland, desert grassland, and shrubland sites in Mongolia. The response of the infiltration rate to short-term livestock removal was also investigated. On the steppe grassland, a high infiltration rate was measured on an ungrazed plot with relatively dense vegetation cover; a statistically significant correlation was found between the total surface cover and final infiltration rate, indicating that surface cover by rock fragments also increased the infiltration rate to some extent. For desert grassland and shrubland, however, the surface cover condition was not a major factor controlling the final infiltration rate. After 4 years of livestock removal, the surface vegetation cover of the ungrazed plot was greater than that of the grazed plot, but no appreciable change occurred in soil penetration resistance. These results suggest that the high infiltration rate on the ungrazed plot was maintained mainly by the recovery of surface vegetation cover after the short-term livestock removal; this may indicate a potential mechanism of recovery from desertification processes for Mongolian rangeland. 相似文献
114.
Matsuo S Hayashi S Watanabe T Adachi K Miyoshi A Kato A Suzuki M 《Journal of toxicologic pathology》2009,22(4):289-292
Emphysematous cystitis is a rare disorder caused by bacterial infection and characterized by gas accumulation within the bladder wall with cyst formation. This report describes the histopathological characteristics of emphysematous cystitis found in a diabetic female beagle induced by streptozotocin and alloxan. Macroscopically, multiple cyst-like structures were observed on the cut surface of the urinary mucosa. During fixation, small specimens cut from the mucosa floated on the surface of the fixative solution. Histopathologically, multiple cysts were lined with a single layer of flattened cells found to be immunohistochemically positive for vimentin, partially positive for α-smooth muscle actin or macrophage scavenger receptor, class A, and thought to be myofibroblasts, fibroblasts or macrophages. Multinucleated giant cells were observed around the cysts, and gram-negative short bacilli were observed in the lumen of the urinary bladder. From these findings, this case was diagnosed as emphysematous cystitis. 相似文献
115.
Hiroaki Kato Shuta Asai Ayako Yamamoto-Katou Hirofumi Yoshioka Noriyuki Doke Kazuhito Kawakita 《Journal of General Plant Pathology》2008,74(1):15-23
During defense responses, plant cells produce nitric oxide (NO), which may control many physiological processes. In a previous
study, we reported that nitrate reductase (NR) is responsible in part for INF1 elicitor-induced NO production in Nicotiana benthamiana, but the possibility remains that other NO-generating system(s) contribute to NO production. In mammalian cells, NO production
is catalyzed by NO synthase (NOS). However, NOS-like enzyme(s) have never been identified in plants, and only the gene for
Arabidopsis thaliana nitric oxide-associated 1 (AtNOA1) has been identified as a putative regulator of NOS activity in plants. In this study, we cloned NbNOA1, a homolog of AtNOA1, from N. benthamiana and investigated its involvement in NO production induced by INF1. The NbNOA1 gene was silenced by a virus-induced gene-silencing (VIGS) technique. NbNOA1-silenced plants had yellowish leaves. Silencing NbNOA1 partially decreased INF1-induced NO production, while overexpressing NbNOA1 did not affect NO production. Silencing NbNOA1 suppressed INF1-induced PR1a gene expression and increased susceptibility to Colletotrichum lagenarium. These results suggest that NbNOA1 is involved in INF1-mediated NO production and is required for defense responses.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB303300. 相似文献
116.
Fui Fui Ching Yoshizumi Nakagawa Keitaro Kato Osamu Murata Shigeru Miyashita 《Aquaculture Research》2012,43(2):303-310
The effects of delayed first feeding on the survival and growth of tiger grouper, Epinephelus fuscoguttatus (Forsskål 1775), larvae were examined under controlled conditions. The total length, yolk sac volume, oil globule volume, yolk sac absorption time and nutritional transition period (NTP) of the larvae fed at different first times (0, 6, 12, 18 and 24 h after the mouth opening stage; h AMO) were compared. Larval first feed intake was observed at 54 h after hatching (h AH) at 27.5 ± 0.5 °C. The yolk sac was consumed more rapidly with an increase in delayed first feeding and was significantly different among treatments (P<0.05). Larvae first fed at 0 h AMO had the longest yolk sac absorption (72 h AH) and NTP (20 h) times and had the highest survival and growth rates at the end of the experimental period (360 h AH), being significantly higher (P<0.05) than the other treatments. First mortality was observed at 69 h AH, approximately 2 h after point of no return (PNR) occurred. This study suggests that first feeding of tiger grouper larvae should commence at 0 h AMO for enhancement of larval survival and growth. 相似文献
117.
Masahiro Kaneda Shinya Watanabe Satoshi Akagi Yasushi Inaba Masaya Geshi Takashi Nagai 《Animal Science Journal》2017,88(11):1678-1685
Epigenetic abnormalities in cloned animals are caused by incomplete reprogramming of the donor nucleus during the nuclear transfer step (first reprogramming). However, during the second reprogramming step that occurs only in the germline cells, epigenetic errors not corrected during the first step are repaired. Consequently, epigenetic abnormalities in the somatic cells of cloned animals should be erased in their spermatozoa or oocytes. This is supported by the fact that offspring from cloned animals do not exhibit defects at birth or during postnatal development. To test this hypothesis in cloned cattle, we compared the DNA methylation level of two imprinted genes (H19 and PEG3) and three non‐imprinted genes (XIST, OCT4 and NANOG) and two repetitive elements (Satellite I and Satellite II) in blood and sperm DNAs from cloned and non‐cloned bulls. We found no differences between cloned and non‐cloned bulls. We also analyzed the DNA methylation levels of four repetitive elements (Satellite I, Satellite II, Alpha‐satellite and Art2) in oocytes recovered from cloned and non‐cloned cows. Again, no significant differences were observed between clones and non‐clones. These results suggested that imprinted and non‐imprinted genes and repetitive elements were properly reprogramed during gametogenesis in cloned cattle; therefore, they contributed to the soundness of cloned cattle offspring. 相似文献
118.
Changes in muscle fiber type and expression of mRNA of myosin heavy chain isoforms in porcine muscle during pre‐ and postnatal development
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Masaya Katsumata Tomomi Yamaguchi Aiko Ishida Akane Ashihara 《Animal Science Journal》2017,88(2):364-371
The purpose of this study is to elucidate developmental changes in muscle fiber type in the pig during pre‐ and postnatal development. For this purpose, we performed a histochemical analysis for myosin adenosine triphosphatase activity to assess muscle fiber type and determined abundances of messenger RNA (mRNA) of myosin heavy chain (MHC) isoforms. Samples of Longissimus dorsi (LD) muscle were taken from fetuses on day 90 of the fetal stage. Further, samples of LD, Rhomboideus and Biceps femoris (B. femoris) muscles were taken from pigs when they were 1, 12, 26, 45 or 75 days old. Expression of MHC 2b mRNA in the LD and the B. femoris muscles rapidly and considerably increased from the late fetal stage to the early postnatal stage and this increase was associated with the development of type 2b fibers at least in the LD muscle. As shown by the rapid and considerable changes in expression of MHC 2b mRNA, it seems that a certain plasticity of muscle fiber type still remains in this developmental stage. 相似文献
119.
Hirofumi Ido Hirofumi Nagao Hideo Kato Atsushi Miyatake Yasushi Hiramatsu 《Journal of Wood Science》2010,56(5):422-428
Tests of compression perpendicular to the grain were carried out on laminated veneer lumber (LVL) and timber. The species
tested were sugi, radiata pine, karamatsu, akamatsu, and dahurian larch; two sets of sugi specimens were tested, with the
sugi LVL products being manufactured in different plants. The strength properties of the materials for different loading directions
were compared for LVL and timber. At 5% compressive strain in the same materials, the average stress in the tangential direction
of timber was larger than that in the radial direction for all species except for radiata pine, and the average stress in
the edge-wise direction of LVL was larger than that in the flat-wise direction for all species except for radiata pine. When
the stress at 5% strain was compared in the same direction, the average stress of LVL in the edge-wise direction was larger
than that in timber in the tangential direction for all species, but there were no great differences between the average stress
of LVL in the fl at-wise direction and that of timber in the radial direction for all species except for radiation pine. There
was a close relationship between density and stress at 5% strain in LVL, especially in the edge-wise direction. For all results,
radiata pine did not follow the trend of the other species; The large annual ring width of radiata pine was considered to
have affected the results. 相似文献
120.
This study on dried shiitake mushroom [Lentinula edodes (Berk.) Pegler] focuses on the behavior of the aromatic lenthionine compound and its precursor, lentinic acid, during the
drying process. Only a small amount of lenthionine was present after the drying process, regardless of the drying temperature
or time; however, the amount increased during the rehydration process using pH 8.0 buffer. The lenthionine content after incubation
in the buffer was correlated with the lentinic acid content in the dried shiitake mushroom. The lentinic acid content increased
signifi cantly during the drying process at 40°C up to 4 h. The results show that the characteristic smell of dried shiitake
mushroom was weak after drying, and that rehydration in a mild alkaline solution was necessary to increase the smell. The
lentinic acid content of dried shiitake could serve as an indicator of the smell produced by rehydration and would be useful
in screening to select odor-rich strains. Moderate heating likely caused the increase in lentinic acid content, which might
be related to a reaction to heat. 相似文献