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401.
Qi J Asano T Jinno M Matsui K Atsumi K Sakagami Y Ojika M 《Science (New York, N.Y.)》2005,309(5742):1828
Water molds of the genus Phytophthora include many plant pathogens responsible for epidemics such as potato blight and sudden oak death, causing global economic damages. Sexual reproduction is of biological importance in Phytophthora and has been believed to be stimulated by unknown endogenous factors named a hormones. We describe here the chemical characterization of a Phytophthora mating hormone, a1, which was obtained from approximately 2 tons of culture fluid of one mating type of a species and which induced sexual spores on the counter-mating type at a nanogram level. 相似文献
402.
以君迁子和美国柿为对照,在果实发育中期,对41个柿品种、45个样品的果实内单宁细胞,进行了组织学镜检。结果表明,一般甜柿较涩柿的单宁细胞数目少,个小,横径/纵径指数小。从果实顶部到基部,单宁细胞的横径变化不显著,但纵径从小到大,横径/纵径指数由大到小,甜柿一般较涩柿变化明显。作为砧木的君迁子和美国柿,果实内单宁细胞数量为普通柿的3~7倍,横径/纵径指数在0.7以上,但果实不同部位差异很小。 相似文献
403.
Journal of General Plant Pathology - A new disease on celery discovered in Japan caused extreme stunting, dwarfed and yellowed leaves, black rot of the celery “heart”, and root rot. A... 相似文献
404.
Demura H Kobayashi S Nemoto E Matsumoto N Furuya M Yukishita A Muranaka N Morita H Shirakawa K Maruya M Ohyama H Uo M Kubota T Hashimoto T Kawaguchi J Fujiwara A Saito J Sasaki S Miyamoto H Hirata N 《Science (New York, N.Y.)》2006,312(5778):1347-1349
The locations of the pole and rotation axis of asteroid 25143 Itokawa were derived from Asteroid Multiband Imaging Camera data on the Hayabusa spacecraft. The retrograde pole orientation had a right ascension of 90.53 degrees and a declination of -66.30 degrees (52000 equinox) or equivalently 128.5 degrees and -89.66 degrees in ecliptic coordinates with a 3.9 degrees margin of error. The surface area is 0.393 square kilometers, the volume is 0.018378 cubic kilometers with a 5% margin of error, and the three axis lengths are 535 meters by 294 meters by 209 meters. The global Itokawa revealed a boomerang-shaped appearance composed of two distinct parts with partly faceted regions and a constricted ring structure. 相似文献
405.
Masaomi Kimura Keigo Noda Tatsuya Makino Hijiri Yamagata Somphasith Douangsavanh Keoduangchai Keokhamphui Hiromasa Hamada Masashi Kiguchi Toshiaki Iida Kazuo Oki 《Paddy and Water Environment》2018,16(3):519-531
Vientiane, Lao PDR, has been subject to extensive and ongoing urbanization plans, including development of natural marshes and residentialization of paddy fields into suburban areas, despite natural marshes playing a vital role in treating wastewater from urban areas. Therefore, it is important to understand the current situation regarding the nutrient balance in these natural wastewater treatment systems to predict future conditions and design appropriate measures against water quality deterioration. However, limited data are available in Vientiane on the hydrological characteristics of water and nutrient runoff that flow into marshes through drainage canals. In this study, we conducted a periodic survey of drainage canals and Mak Hiao River in the wastewater catchment system surrounding Vientiane during the rainy and dry seasons. We monitored the discharge of surface water at 21 observation sites and analyzed water quality of nitrogen, phosphorus, and total organic carbon. These observations revealed that the concentrations of dissolved nitrogen and phosphorus were significantly higher at sites in urban areas, followed by sites in the main river basin and those in agricultural areas. Dissolved nitrogen and phosphorus concentrations varied with runoff discharge, especially in urban and river basin sites, with lower concentrations in the rainy season and higher concentrations in the dry season. On the other hand, we found no significant differences between the rainy and dry seasons in nutrient concentrations in the agricultural basin. Finally, we proposed measures to counteract the deterioration of water quality during dry seasons and simulated the impact of these measures. 相似文献
406.
Functional insulin‐like factor 3 (INSL3) hormone‐receptor system in the testes and spermatozoa of domestic ruminants and its potential as a predictor of sire fertility
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Ali M. Pitia Kyoko Uchiyama Hiroaki Sano Masashi Kinukawa Yoshiaki Minato Hiroshi Sasada Tetsuya Kohsaka 《Animal Science Journal》2017,88(4):678-690
Insulin‐like factor 3 (INSL3) is essential for fetal testis descent, and has been implicated in the testicular and sperm functions in adult males; however, similar functions in domestic ruminants remain largely unknown. This study investigated the functional INSL3 hormone‐receptor system in adult ruminant testes and spermatozoa, and explored its potential to diagnose the fertility of sires. Testes and spermatozoa were obtained from fertile bulls, rams and he‐goats, whereas subfertile testes and spermatozoa were obtained only from bulls. As expected, INSL3 was visualized in Leydig cells, while we clearly demonstrated that the functional receptor, relaxin family peptide receptor 2 (RXFP2), enabling INSL3 to bind was identified in testicular germ cells and in the sperm equatorial segment of bulls, rams and he‐goats. In comparison to fertile bulls, the percentage of INSL3‐ and RXFP2‐expressing cells and their expression levels per cell were significantly reduced in the testes of subfertile bulls. In addition, the population of INSL3‐binding spermatozoa was also significantly reduced in the semen of subfertile bulls. These results provide evidence for a functional INSL3 hormone‐receptor system operating in ruminant testes and spermatozoa, and its potential to predict subfertility in sires. 相似文献
407.
Pirarat Nopadon Ponpornpisit Aranya Nakai Toshihiro Maita Masashi 《Research in veterinary science》2009,87(1):97-95
The present study characterized viral nervous necrosis in sea cage-reared adult spotted coralgroupers (Plectropomus maculatus). Histopathological study showed extensive vacuolation and neuronal necrosis of the olfactory bulb and the optic lobe of the forebrain and the inner and outer nuclear layer of retina. Mild necrosis was observed in the spinal cord. Homogeneous intranuclear inclusion bodies were noted in the hyperplastic and hypertrophic glandular epithelial cells of the swim bladder suggesting viral etiology. Etiological diagnosis of VNN was confirmed by RT-PCR, immunohistochemistry and in situ hybridization. The immunohistochemistry and in situ hybridization gave strongly positive staining in the same area of the infected cells of the brain, spinal cord and retina correlating with histopathological changes. No positive reaction was detectable in the affected gas glandular epithelium and other organs, confirming the consistent neurotropism of this nodavirus. Nodavirus was mainly detected in the olfactory bulb of the brain. The result suggests nasal transmission was the major route of infection. 相似文献
408.
The purpose of this study was to measure the dynamics of serum α1-acid glycoprotein (AGP) concentration in dogs with various
tumors, and to investigate the localization of AGP in some tissues using immunohistochemical staining. Sera were obtained
from 171 dogs bearing tumors of various types. Serum AGP concentration was measured by single radial immunodiffusion. Tumors
occurring in the liver and spleen were also investigated immunohistochemically using anti-canine AGP antibody. Mean serum
AGP levels were 749 ± 602 mg/L in dogs with carcinoma (n = 39), 1,014 ± 971 mg/L with sarcoma (n = 18), and 887 ± 935 mg/L with round cell tumors (n = 46), all significantly higher than serum AGP level in healthy dogs (n = 137, 364 ± 106 mg/L). Mean serum AGP levels were significantly higher than in healthy dogs in complex mammary gland carcinoma
(n = 5, 876 ± 721 mg/L), malignant melanoma (n = 7, 1,010 ± 821 mg/L), and hepatocellular carcinoma (n = 5, 936 ± 741 mg/L) among carcinomas, hemangiosarcoma (n = 5, 1,740 ± 1,323 mg/L) among sarcomas, and lymphoma (n = 19, 1,072 ± 965 mg/L) and histiocytic tumor (n = 6, 1,800 ± 1,387 mg/L) among round cell tumors. In an immunohistochemical investigation of AGP localization, both weak
and strong staining for anti-AGP antibody were seen in hepatic tissue in dogs with primary non-tumorous lesions originating
in the spleen (hematoma) and elevated serum AGP, but all tumor tissue in the spleen was negative. Among dogs with primary
tumor lesions of the spleen (hemangiosarcoma) and elevated serum AGP levels, both weak, moderate and strong staining for anti-AGP
antibody were seen in hepatic tissue, while strong positive staining was apparent in all tumorous tissue from the spleen.
In primary tumor lesions in the liver (hepatocellular carcinoma), both moderate and strong staining for anti-AGP antibody
were seen in normal hepatic tissue, and both weak, moderate and strong staining were seen in tumor tissues of the liver. AGP
levels thus appear to be elevated in dogs with carcinomas, sarcomas, and round cell tumors. With some of these malignant tumors,
localization of AGP in tumor tissue was seen. 相似文献
409.
Nattapong NINPETCH Dagvajamts BADRAKH HAY MAR KYAW Kohei KAWANO Yojiro YANAGAWA Masashi NAGANO Seiji KATAGIRI 《The Journal of reproduction and development》2022,68(3):209
Factors associated with high milk production levels have been linked to alterations in the endometrial epidermal growth factor (EGF) profile, a cause of reduced fertility in dairy cows. Therefore, we examined the leptin system that connects nutritional status and reproduction in dairy cattle related to reduced fertility in repeat breeder cows. Plasma leptin concentrations were measured in 18 heifers, 20 high-yielding control cows, and 26 repeat breeder cows, showing an altered EGF profile. Then, all repeat breeder cows were infused with seminal plasma (SP) into the vagina at the next estrus to normalize the EGF profile, while heifers and control cows were infused with vehicle alone. All animals were examined for EGF profiles. Eighteen repeat breeder cows, nine heifers, and nine control cows were also determined for leptin receptor (Ob-R) expression levels in the estrous cycle before and after the infusion. SP normalized the EGF profile in 53.8% of the repeat breeder cows. Leptin concentrations were similar in all groups, regardless of the treatment results for the EGF profile. In contrast, Ob-R levels in repeat breeder and control cows were similar and higher than those in heifers before SP treatment. Ob-R in repeat breeders showing a normal EGF profile after treatment decreased to an intermediate level between heifers and control cows and may provide a clue to take measures against repeat breeding in dairy cows. 相似文献