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121.
White plastic insect traps (manufactured by Sankei Chemical Co., Ltd.) equipped with four chemicals with floral scents, namely, benzyl acetate, methyl benzoate, methyl phenylacetate and linalool, were set from June 28 to August 9, 1996. The traps were placed in a Japanese beech (Fagus creata) forest, Minakami, Gunma Prefecture, Central Japan, and trapped longicorn beetles were collected weekly. The greatest number of species and individuals belonged to the subfamily Lepturinae dominated by the genusPidonia. No significant differences were observed in the performances of the above four chemicals in either the total number of species or of individuals. However, more Lamiinae species were captured in the traps with methyl phenylacetate, than in those with methyl benzoate. A part of this paper was presented at the 48th Meeting of the Kanto Branch of the Jpn. For. Soc. (1996).  相似文献   
122.
The brain nanopeptide arginine vasotocin (AVT) and its mammalian homolog arginine vasopressin are involved in the regulation of social and reproductive behavior. We investigated the relationship between social rank formation and the brain AVT system in the false clown anemonefish (Amphiprion ocellaris), which forms a social rank that leads to sex differentiation in higher-ranked individuals. Tanks of three sexually immature fish were kept for 90 days and each fish’s behavior was observed once a month. The social rank of each individual was distinguishable by behavior, but gonadosomatic index (GSI) did not differ significantly. The number of AVT neurons in the magnocellular layer in the preoptic area (POA) increased in subordinate individuals and declined with increasing hierarchical dominance. These results suggest that social rank formation modulates AVT production in the brain of the clown anemonefish and may influence their later sex differentiation.  相似文献   
123.
The research field of “Toxicologic Pathology” evaluates potentially toxic chemical exposures and chemically mediated illnesses in humans and experimental animals. Comparative studies of chemical exposures between model organisms and humans are essential for the risk assessment of chemicals and human health. Here we review the development and activities of the Japanese Society of Toxicologic Pathology (JSTP) during its 37-year history. Toxicological pathology studies provide many interesting and valuable findings. Rodent cancer bioassay data demonstrate the importance of dose levels, times, and duration of exposures to chemicals that possibly cause human cancers. Studies of toxic injuries in the nasal cavity demonstrate that specific chemical compounds affect different target cells and tissues. These observations are relevant for current air pollution studies in the preventive medicine field. Future toxicological pathology studies will be enhanced by applying molecular pathology with advanced observation techniques. In addition to the nasal cavity, another sense organ such as the tongue should be a potential next program of our mission for risk assessment of inhaled and ingested chemicals. As a message to the younger members of the JSTP, interdisciplinary and global cooperation should be emphasized. Elucidating the mechanisms of toxicologic pathology with a combination of advanced expertise in genetics and molecular biology offers promise for future advances by JSTP members.  相似文献   
124.
Method of lymphocytotoxic crossmatch test for feline renal transplantation.   总被引:1,自引:0,他引:1  
The optimal condition for methods of lymphocytotoxic crossmatch test for feline renal transplantation was investigated. On separation of viable lymphocytes from whole blood, the best results were obtained when Ficoll-diatrizoate with 1.078 of a specific gravity at 20 degrees C was centrifuged with 800 x g for 30 min at 4 degrees C. A nylon wool column was used to separate T and B cells from lymphocyte fraction. The ratio of T cells in nylon wool effluent cells was 95%, while the ratio of B cells in adherent cells was 41%. Lymphocytotoxic crossmatch tests were performed by using the effluent cells as T cells and the adherent cells as B cells, at 37 degrees C (warm) and 4 degrees C (cold). The ratio of B cells in adherent cells was low, however, the result was utilized as a matching test before transplantation by combining with the T cell result. The trypan blue stain method made it easier than the eosin stain method to distinguish living and dead cells. The lymphocytotoxic crossmatch tests were performed on 15 pairs of healthy cats, and only one pair showed doubtful positive against anti-B cell cold antibodies. During acute rejection after renal transplantation in two pairs which were negative on any anti-lymphocyte antibodies before the transplantation, the anti-T cell warm antibodies became positive in both pairs, and the anti-T cell cold antibodies became positive on one of the two pairs.  相似文献   
125.
The osmoregulatory ability of chum salmon (Oncorhynchus keta), reared in fresh water for a prolonged period, was examined by transferring them directly to seawater and then back to fresh water. When fry and juveniles weighing 0.3–125g, reared in fresh water for 1.5–13 months, were transferred directly to seawater, they adjusted their plasma Na+ concentration to the seawater-adapted level within 12–24h. When they were transferred back to fresh water after having been adapted to seawater for 2 weeks, the plasma Na+ level gradually decreased during the first 12–24h, and then increased to reattain the initial freshwater level after 5–7 days. No mortality was observed during the experiment except among the smallest fry weighing about 0.3g after transfer to seawater (2.1%). The maintenance of good osmoregulatory ability of the chum salmon for a prolonged period in fresh water seems to be unique among Pacific salmon, with the possible exception of the pink salmon.Changes in plasma levels of hormones during the transfer experiments were recorded in juveniles reared in fresh water for 13 months. Prolactin levels increased maximally 3 days after transfer from seawater to fresh water, as would be expected from its well-established role in freshwater adaptation in several euryhaline teleosts. In addition, an increase in plasma growth hormone was observed during the first 12h after seawater transfer, along with a tendency towards a decrease during freshwater transfer, suggesting an important role for this hormone in seawater adaptation. There were no consistent changes in plasma levels of thyroxine and cortisol during freshwater to seawater or seawater to freshwater transfer.  相似文献   
126.
Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the plant to assess the marketable product (fruit). In this article, we describe the potential of genomics-assisted breeding, which uses these novel genomics-based approaches, to break through these barriers in conventional fruit tree breeding. We first introduce the molecular marker systems and whole-genome sequence data that are available for fruit tree breeding. Next we introduce the statistical methods for biparental linkage and quantitative trait locus (QTL) mapping as well as GWAS and GS. We then review QTL mapping, GWAS, and GS studies conducted on fruit trees. We also review novel technologies for rapid generation advancement. Finally, we note the future prospects of genomics-assisted fruit tree breeding and problems that need to be overcome in the breeding.  相似文献   
127.
Mitochondrial numbers increase during oocyte growth. In this study, we collected oocytes and granulosa cell complexes (OGCs) from early antral follicles (EAFs) of aged cows (> 120 months of age) and examined the effects of resveratrol on mitochondrial generation, degradation, and quality in oocytes grown in vitro. We also examined the effects of resveratrol on gene expression of the granulosa cells. Resveratrol (20 µM) enhanced the expression of SIRT1 and induced autophagy in both granulosa cells and oocytes derived from aged cows. Culturing the OGCs with resveratrol increased mitochondrial DNA copy numbers in oocytes grown in vitro. Furthermore, resveratrol increased the ATP content in oocytes and improved the developmental ability of the oocytes to the blastocyst stage. Gene expression profiles in granulosa cells, as evaluated by next-generation sequencing technology, revealed that resveratrol enhanced the expression of EIF2-related genes but downregulated the expression of mammalian target of rapamycin (mTOR)-, inflammation-, and cholesterol homeostasis-related genes in granulosa cells. In conclusion, resveratrol affected both oocytes and granulosa cells derived from aged cows and improved the quality of oocytes grown in vitro through upregulation of mitochondrial biogenesis and degradation in growing oocytes and conditioning of granulosa cells.  相似文献   
128.
In Primula sieboldii E. Morren, many cultivars have been bred with the purpose of obtaining various petal colour patterns. Colour pattern is an important breeding target in this species, and the availability of an objective and quantitative evaluation method is of vital importance for both genetic analysis and variety registration. Our objective was to establish a new quantitative evaluation method of P. sieboldii flower colour patterns in regions of interest (ROIs) by principal component analysis (PCA). We first set a ROI in each petal as a region that represented the petal colour pattern and defined the maximum square on each petal as the ROI. We then converted each ROI image to a 10 × 10 pixel mosaic image and defined a total of 300 variables (the colour values for red, green and blue components of the 100 pixels) per mosaic image. Finally, we summarized the information on the 300 variables by PCA, and redrew the mosaic images to correspond to some typical principal component scores to determine the effect of each principal component on colour pattern. By this method, we detected five different features of petal colour pattern, four of which were revealed to be mainly genetically controlled. Thus, we successfully established a procedure for evaluating petal colour patterns in P. sieboldii cultivars. This new procedure can be used as a basis for an objective and efficient variety registration system.  相似文献   
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