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71.
A newborn Holstein female calf had neoplastic lesions in the skin and within the thoracic and abdominal cavities but not in the bone marrow, spleen, thymus, or most lymph nodes. Because the tumor cells were positive for CD79a (B cell marker), CD5 (B-1 cell marker) and terminal deoxynucleotidyl transferase (marker for immature lymphoid precursors), a diagnosis of precursor B-1 B cell lymphoma was made. The diagnosis was strongly supported by the fact that B-1 cells can develop in the fetus, unlike B-2 cells, which are produced after birth. The lymphoma was distinct from the typical calf form of lymphoma of B-2 cell origin, which does not express CD5 and is characterized by generalized lymphadenopathy and involvement of the bone marrow, blood and spleen.  相似文献   
72.
Muscular dystrophies, a group of inherited diseases with the progressive weakness and degeneration of skeletal muscle, contain genetically variable diseases. Though chicken muscular dystrophy with abnormal muscle (AM) has long been known, the gene responsible has not yet been identified. In this study, a resource family for AM was established with 487 F2 individuals and 22 gene markers, including microsatellite and insertion–deletion markers, were developed. The haplotypes were analyzed with these markers for the candidate region of GGA2q described in a previous study. The candidate region was successfully narrowed down to approximately 1Mbp. The region included seven functional genes predicted as the most likely AM candidates.  相似文献   
73.
In this study, we performed a molecular phylogenetic analysis of six bovine papular stomatitis virus (BPSV) field strains detected from Japanese beef calves kept on a farm in Saga prefecture, a southwest part of Japan, from 2017 to 2020. The phylogenetic analysis based on a partial B2L gene (554-nt) showed that these field strains were divided into two lineages, a lineage (A-lineage) constructed by a Saga strain and strains obtained from various regions of Japan and the world, and other lineage (B-lineage) constructed by five Saga strains and strains obtained from France, USA and Iwate prefecture (a north part of Japan). Furthermore, a Saga field strain named BPSV_SAGAbv2 and strains obtained from USA and Iwate prefecture belonged to a sub-lineage blanched from B-lineage. This is the first report elucidating molecular epidemiological characters of field BPSVs obtained from Saga prefecture. The existence of the multiple lineages was thought to be related to a history of calf introduction from various regions of Japan into Saga prefecture.  相似文献   
74.
Methyl‐mannosylerythritol lipid (MEL), a new sugar esterified lipid synthesized by Pseudozyma aphidis, was assessed for its functionality in modulating rumen fermentation and microbiota toward more propionate and less methane production. A pure culture study using rumen representatives showed that MEL selectively inhibited the growth of most Gram‐positive bacteria including Streptococcus bovis, ruminococci, and Fibrobacter succinogenes, but not Gram‐negative bacteria such as Megasphaera elsdenii, Succinivibrio dextrinosolvens, and Selenomonas ruminantium. A batch culture study revealed that MEL significantly decreased methane production in a dose‐dependent manner with accumulation of hydrogen, while propionate production was enhanced. A continuous culture (Rusitec) study confirmed all of these changes. A feeding study revealed that sheep fed a MEL diet showed an increased proportion of propionate, while proportions of acetate and butyrate were decreased without affecting total VFA level. These changes disappeared after cessation of MEL feeding. Based on these results, dietary application of MEL can favorably modify rumen fermentation in terms of the efficiency of dietary energy utilization.  相似文献   
75.
Ovarian developmental stages and serum steroid hormone levels were examined at six different times of day (0100, 0600, 1000, 1300, 1600, 2000 h) in a marine teleost, the Japanese whiting Sillago japonica, which has an asynchronous-type ovary containing oocytes at various stages of development and spawns every day during a period ranging up to three months. The largest oocytes in the ovaries at the active vitellogenic or post-vitellogenic stages were found between 0100 and 1300 h. Oocyte maturation indicated by germinal vesicle breakdown (GVBD) occurred at 1600 h, and ovulated oocytes were observed in the ovaries collected at 2000 h. These processes were accompanied by a significant daily change in serum steroid hormone levels. The serum level of estradiol-17β showed a peak in fish with mature oocytes sampled at 1600 h. In these fish, the second-largest oocytes in the ovaries were at the initial stage of vigorous vitellogenesis, the secondary yolk stage. Therefore the highest level of serum estradiol-17β was considered to be due to the second-largest oocytes. Testosterone levels remained low and constant throughout the experimental period. The serum levels of 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-diOHprog) peaked at 1600 h at which time all fish had mature oocytes. These results indicate that the Japanese whiting possesses a diurnal rhythm of oocyte development including vitellogenesis, oocyte maturation and ovulation, and further suggest that daily cycles in oocyte growth and maturation which simultaneously take place in an ovary are regulated by diurnal secretions of estradiol-17β and the maturation-inducing steroid, 17α,20β-diOHprog.  相似文献   
76.
77.
The arching and high-rack culture systems were developed and patented by Japanese rose growers. Both culture systems have bent canopies (lower bent shoots). In the arching culture system, shoots sprouting from the crown are harvested as cut flowers. However, the high-rack culture system also has a bent canopy originating from the mother stem (upper bent shoots) and flower stems sprout and is harvested at the top of each mother stem. Partitioning of photosynthates originating from bent shoots in arching and high-rack culture systems of rose production was investigated to elucidate how carbohydrates are re-allocated from the bent shoots in different culture systems of roses. At the flowering stage in both culture systems, 50–70% of 13C-photosynthates originated from bent shoots were exported to other parts within 72 h after 13CO2 feeding to the bent shoot. In the arching culture system, photosynthates from lower bent shoots were partitioned mainly to the roots and crown. Similarly, in the high-rack culture system, between 71 and 86% of the exported carbon from the bent shoots were allocated to below the point of bending (roots + crown + mother stems) and only 9–28% was allocated to flowering shoots above the point of bending. In both culture systems, photosynthate translocation from the lower bent shoot directly to flowers was low. Accordingly, bent shoots in rose plants acted as a source of photosynthates, independent of culture system. The height of the bent shoots determined for a great deal in the re-allocation of the photosynthates, and provides a partial explanation for difference in production of cut roses.  相似文献   
78.
Calves (n = 106) on four dairy farms were observed for their approachability to humans. All calves experienced similar rearing conditions: Beginning individual pen, after birth until weaning at about 2 months, where they were housed individually and fed milk and a milk replacement; Late individual pen, after weaning until grouping at about 3.5 months, where they were housed individually and fed hay, silage and concentrate feed; Beginning group pen, after grouping until 5 months, where they were housed in groups of 2–5 animals and fed hay, silage and concentrate feed; later group pen, from 5 to 7 months. The number of calves that contacted an experimenter who stood in front of their pens for 10 min was recorded on 6 separate days over 3 months. Latency to touch and time spent in activities during touching such as sucking, licking, biting and rubbing were also measured. There were no significant differences in the latency to touch and the ratio of touch to non‐touch calves between the rearing conditions and the farms. The time spent touching was significantly affected by the interaction between the rearing condition and the farm (P < 0.01). In detail, the time spent sucking (P < 0.001) and licking (P < 0.01) was different between the rearing condition × farm variables. The proportion of calves that approached and touched the experimenter tended to be higher in the farms in which a stockperson worked longer inside and outside their pens (both ρ = 0.95, P = 0.051). These results were interpreted according to the perspectives of early positive reinforcement with food and the habituation process to humans existing nearby.  相似文献   
79.
Chemical investigations of the Egyptian soft coral Sarcophyton ehrenbergi have led to the isolation of compounds 1–3 as well as the previously reported marine cembranoid diterpene sarcophine (4). Structures were elucidated by comprehensive NMR and HRMS experimentation. Isolated compounds were in vitro assayed for cytotoxic activity against human hepatocarcinoma (HepG2) and breast adenocarcinoma (MCF-7) cell lines.  相似文献   
80.
In the field of agriculture, development of evaluation techniques for environmental changes is urgently required for the purpose of finding a balance between growth in agricultural productivity and environmental considerations. The habitat evaluation procedures (HEP) constitute one technique for habitat assessment. While HEP is widely applied to estimate both habitat quality and quantity in an environment, it appears to be necessary to develop an accurate habitat prediction model in order to evaluate environments precisely. In fact, habitat selection by fish is affected by complicated interaction between multiple environmental factors, which makes it difficult to relate physical environments to habitat preference. In the present study, we utilize artificial neural networks (ANNs), which are commonly applied to model complex systems, to predict the habitat selection of Japanese medaka (Oryzias latipes) in agricultural canals. Considering the essential vagueness of fish behavior, fuzzy membership functions are introduced into the input layer, which advances ANN to fuzzy neural network (FNN). In addition, symmetric triangular fuzzy numbers are employed to account for uncertainty in measurement errors and dispersions of physical environment. The FNN model precisely predicts the habitat preference of Japanese medaka in an agricultural canal, and the results show a good agreement between the calculated and observed habitat suitability indices (HSI). Finally, the habitat quality of two different reaches at the same point in time is compared using HEP, with a view of suitable habitat for Japanese medaka.  相似文献   
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