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961.
962.
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 下载免费PDF全文
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
963.
Effect of ensiling process of total mixed ration on fermentation profile,nutrient loss and in situ ruminal degradation characteristics of diet 下载免费PDF全文
This experiment aimed to determine the changes in chemical composition, fermentation profile, in situ disappearance characteristics, and nutrient losses of ensiled total mixed ration (TMR) containing steam‐flaked corn or brown rice (BR) during storage. TMRs for dairy cows, containing either steam‐flaked corn or BR at 31.9% with 15.2% rye silage, 40.5% alfalfa silage, 5.0% beet pulp and 7.0% soybean meal, were prepared (dry matter (DM) basis). Each TMR was placed in a plastic drum silo, stored at 23°C in an air‐conditioned room and sampled 0, 7, 14, 30, 90 and 210 days after preparation. In both grain sources, the fermentation products increased, while DM and starch storage losses increased and starch content greatly decreased during storage. The rapidly degradable fraction and effective ruminal degradability of DM, crude protein and starch increased during storage. These changes of dietary characteristics were large during 30 days of storage, but small after 90 days of storage. Replacing corn with BR led to increased fermentation products, starch loss and effective ruminal degradability of the ensiled TMR. These results indicate that the ensiling process of TMR changes the dietary characteristics and replacing corn with BR in TMR had a large impact on these dietary characteristics. 相似文献
964.
Apple dimple fruit viroid was detected from an apple tree (‘Jonagold’) bearing apples with mild dapple apple symptom. The isolates in Japan were distinct from those in apples in Italy and China and in fig in Italy. Graft-inoculation experiments showed that the symptoms were variable depending on the cultivar, and the symptom on ‘Starking Delicious’ was virtually similar to those reported in Italy. Symptoms induced by apple dimple fruit viroid were similar in part to those by apple fruit crinkle viroid or apple scar skin viroid, indicating that they cannot be discriminated by symptoms on any specific variety. 相似文献
965.
Sakae Horisawa Makoto Yoshida Kiwamu Umezawa Tomoko Wada Hisashi Abe Shuichi Doi Masahiro Samejima Ikuo Momohara 《Journal of Wood Science》2017,63(4):369-378
The diversity and community structures of wood-inhabiting fungi in 16 decayed wood samples from ten wooden houses in Japan were analyzed using a next-generation sequencing (NGS) to determine the fungi responsible for wood decay. DNA of fungi in decayed wood was extracted directly, the internal transcribed spacer (ITS) region in ribosomal DNA (rDNA) was amplified by polymerase chain reaction (PCR), and then, sequences of tagged ITS fragments were analyzed by NGS. Results of sequencing indicated that 68 species of ascomycetes, 37 species of basidiomycetes, and one fungus each from Mortierellales and Mucoromycetes were detected. The fungal community structures showed diversity and included various species of ascomycetes. A microscopic examination of cell wall structure in decayed wood samples suggested that some ascomycetes were soft-rot fungi. Heat map analysis indicated that the similarity in the structures of fungal communities was influenced to a greater extent by the wood species of samples than where they were used as a component. 相似文献
966.
Makoto Higashino Andrew J. Erickson Francesca L. Toledo-Cossu Scott W. Beauvais Heinz G. Stefan 《Water, air, and soil pollution》2017,228(2):80
Saline melt water from road salt applications that has percolated into a fine sandy soil in winter is rinsed out of the soil by infiltrating rainwater in the following warmer seasons. This sequence of saturated and unsaturated flow processes associated with saline water transport in a fine sandy soil was studied by simulation and exploratory laboratory experiments. Experiments in soil columns of 300-μm sand revealed that two rinses of pure water, each of one pore volume, were sufficient to reduce the salt concentration by 99% of its original value in the soil column. Simulated time variations of salt concentration in the effluent from the column agreed with experimental results. Based on simulated and experimental results, a sandy soil must become saturated to experience pore water flow in order to efficiently rinse saline snowmelt water. Depending on the saturated hydraulic conductivity and the soil depth, days, weeks, or months of freshwater infiltration in summer are needed to rinse saline melt water from an unsaturated sandy soil after road salt applications in winter. This explains findings of significant salt concentrations in surface and shallow groundwater during summer months, long after road salt application and infiltration has ceased. 相似文献
967.
Atsuko Imaoka Makoto Ueno Junichi Kihara Sakae Arase 《Journal of General Plant Pathology》2008,74(2):109-116
When exposed to light, the Sekiguchi lesion (sl) rice mutant has an enhanced resistance to Magnaporthe grisea infection responsible for Sekiguchi lesion formation and tryptamine accumulation. Glyphosate [N-(phosphonomethyl) glycine] pretreatment suppressed Sekiguchi lesion formation and tryptamine accumulation in the sl mutant after M. grisea infection even under light. This inhibition by glyphosate was blocked by the supply of exogenous tryptophan, but not by exogenous
phenylalanine. In glyphosate-pretreated leaves, 5-enol-pyruvyl-shikimate-3-phosphate synthase gene expression and tryptophan
biosynthesis were significantly suppressed. During tryptophan starvation, catalase activity was maintained at a high level
even under light, leading to the suppression of H2O2 generation and DNA fragmentation. These results show a strong relationship between the tryptophan and tryptamine pathways
in the induction of light-enhanced resistance to M. grisea infection in the sl mutant. 相似文献
968.
Hiroaki Kurogi Noritaka Mochioka Makoto Okazaki Masanori Takahashi Michael J. Miller Katsumi Tsukamoto Daisuke Ambe Satoshi Katayama Seinen Chow 《Fisheries Science》2012,78(3):525-532
The common Japanese conger Conger myriaster is an important commercial coastal fisheries species in East Asia, but its spawning area has not been determined. A larval
sampling survey was conducted in September 2008 along 136°E between 13°N and 22°N, which roughly followed the Kyushu-Palau
Ridge in the western North Pacific. Twenty larval specimens were confirmed to be C. myriaster using DNA analysis. Two were newly hatched larvae (preleptocephali) 5.8 and 7.8 mm in total length (TL), which were caught
at 17°N. The 5.8 mm TL larva was estimated to be 3–4 days after hatching, the youngest preleptocephalus (i.e., the earliest
stage) of this species ever collected. Eighteen other leptocephali were caught at 18°N and 21°N, and these ranged from 18.6
to 40.0 mm TL. Based on these collections, we discerned that there is a spawning area of C. myriaster in the area along the Kyushu-Palau Ridge approximately 380 km south of Okinotorishima Island. Similar to the Japanese eel
spawning area along the West Mariana Ridge, the Kyushu-Palau Ridge may play an important role as a landmark of the spawning
area. The discovery of this offshore spawning area should lead us to a better understanding of the recruitment mechanisms
of C. myriaster, and help to facilitate future international management efforts. 相似文献
969.
Kawai K Sakairi T Tanaka M Shinozuka J Ide M Sato H Fujiwara T Sano F Kume E 《Journal of toxicologic pathology》2010,23(1):59-62
A hepatic nodule was noted in a C57BL/6J mouse with diet-induced obesity at 53 weeks of age. Macroscopically, a protruding yellowish white nodule was observed on the visceral surface of the left lateral lobe. Light microscopy demonstrated clear demarcation from the compressed adjacent parenchyma, with loss of the distinct lobular pattern. The proliferating cells of the lesion varied in shape and showed cellular atypia and prominent nucleoli along with vacuoles of various sizes. Some of the cells contained various-sized eosinophilic inclusion bodies in their cytoplasm, and electron microscopy revealed the presence of lipid droplets in the rough endoplasmic reticulum. Eosinophilic inclusions were observed as electron dense granular material in the rough endoplasmic reticulum, with one or a few low density central cores. A diagnosis of hepatocellular adenoma was made based on these findings. 相似文献
970.
Morita R Jin M Ogawa B Kuwata K Shibutani M Mitsumori K 《Journal of toxicologic pathology》2010,23(2):95-98
A 10-year-old female miniature poodle had a mass in its carpal joint of the left forelimb. The tumor was divided into small multiple lobules by delicate connective tissues, and necroses were found in some of the central lobules. In some connective stromal areas, chondroid and osteoid tissues were formed. The tumor cells were similar to the structure of apocrine gland epithelial cells with apical blebs resembling apocrine secretion and eosinophilic secretary materials within the luminal space, and spindle cells were sometimes found in the basal area of the glandular structure. In some areas, tumor cells invaded in the blood vessels, bone and bone marrow. Immunohistochemically, the tumor cells forming tubulo-acinar to solid structures were intensely positive for cytokeratin and keratin K8/K18, and the spindle cells were positive for vimentin and alpha-smooth muscle actin. This case was diagnosed as a malignant mixed apocrine gland tumor with metastases to the bone and bone marrow. 相似文献