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91.
It has long been known that a bacterial leaf blight-resistant line in rice obtained from a crossing using ‘Asominori’ as a resistant parent also has resistance to blast, but a blast resistance gene in ‘Asominori’ has not been investigated in detail. In the present study, a blast resistance gene in ‘Asominori’, tentatively named Pias(t), was revealed to be located within 162-kb region between DNA markers YX4-3 and NX4-1 on chromosome 4 and to be linked with an ‘Asominori’ allele of the bacterial leaf blight resistance gene Xa1, tentatively named Xa1-as(t). An ‘Asominori’ allele of Pias(t) was found to be dominant and difference of disease severity between lines having the ‘Asominori’ allele of Pias(t) and those without it was 1.2 in disease index from 0 to 10. Pias(t) was also closely linked with the Ph gene controlling phenol reaction, suggesting the possibility of successful selection of blast resistance using the phenol reaction. Since blast-resistant commercial cultivars have been developed using ‘Asominori’ as a parent, Pias(t) is considered to be a useful gene in rice breeding for blast resistance.  相似文献   
92.
Invertebrate ligand-gated chloride channels are well recognized as important targets for several insecticides and anthelmintics. Hco-UNC-49 is a GABA-gated chloride channel from the parasitic nematode Haemonchus contortus and is an orthologue to the neuromuscular receptor (Cel-UNC-49) from the free-living nematode Caenorhabditis elegans. While the receptors from the two nematodes are similar in sequence, they exhibit different sensitivities to GABA which may reflect differences in in vivo function. The aim of the current study was to further characterize the pharmacology of the Hco-UNC-49 receptor by examining its sensitivity to various insecticides and anthelmintics using two-electrode voltage clamp. Specifically, the insecticides fipronil and picrotoxin appear to inhibit the channel in a similar manner. The IC(50) of picrotoxin on the homomeric channel was 3.65 ± 0.64 μM and for the heteromeric channel was 134.56 ± 44.12 μM. On the other hand, dieldrin, a well-known insect GABA receptor blocker, had little effect on the UNC-49 channel. The anthelmintics ivermectin and moxidectin both moderately potentiated the activation of Hco-UNC-49 by GABA, while piperazine was able to directly activate both the Hco-UNC-49 homomeric and heteromeric channels with EC(50) values of 6.23 ± 0.45 mM and 5.09 ± 0.32 mM, respectively. This piperazine current was reversibly blocked by picrotoxin which demonstrates that the anthelmintic specifically targets Hco-UNC-49. These results demonstrate that Hco-UNC-49 exhibits binding sites for several molecules including piperazine and macrocyclic lactone anthelmintics. In addition, this is the first report of the heterologous expression and subsequent characterization of a receptor for piperazine.  相似文献   
93.
The delineation of the fowl's hypoglossal nucleus was determined by severing the hypoglossal nerve or its branches and observing retrograde degeneration. Birds were killed 7 or 10 days after surgery, the brains embedded in paraffin and cut at 10 μm. Transection of the hypoglossal nerve stem resulted in chromatolysis near the obex and no chromatolysis was found in the Nuclei cervicales. Severing of the laryngolingual branch led to degeneration phenomena near the obex nearly similar to the degeneration observed after severing of the hypoglossal nervestem. Cutting of the superior laryngeal branch caused a degeneration of cells caudal to the obex, and cutting of the syringeal branch resulted in chromatolysis in about the same area. The origin of the anastomosing branch between the first cervical and hypoglossal nerve was not found because no chromatolytic cells could be detected. Similarly the cutting of several upper cervical nerves did not lead to chromatolysis in the areas we investigated.  相似文献   
94.
95.
Cordyceps militaris is a potential harbour of bio-metabolites for herbal drugs and evidences are available about its applications for revitalization of various systems of the body from ancient times. Amongst all the species, C. militaris is considered as the oldest source of some useful chemical constituents. Besides their popular applications for tonic medicine by the all stairs of the community, the constituents of C. militaris are now used extensively in modern systems of medicine. The current survey records the mysterious potentials of C. militaris are boosting up the present herbal treatments, as well as gearing up the green pharmacy revolution, in order to create a friendly environment with reasonable safety. Evidence showed that the active principles of C. militaris are beneficial to act as pro-sexual, anti-inflammatory, anti-oxidant/anti-aging, anti-tumour/anti-cancer/anti-leukemic, anti-proliferative, anti-metastatic, immunomodulatory, anti-microbial, anti-bacterial, anti-viral, anti-fungal, anti-protozoal, insecticidal, larvicidal, anti-fibrotic, steroidogenic, hypoglacaemic, hypolipidaemic, anti-angiogenetic, anti-diabetic, anti-HIV, anti-malarial, anti-fatigue, neuroprotective, liver-protective, reno-protective as well as pneumo-protective, let alone their other synergistic activities, which let it be marketable in the western countries as over-the-counter medicine. A number of culture techniques for this mushroom have been noticed, for example, storage/stock culture, pre-culture, popular/indigenous culture (spawn culture, husked rice culture and saw dust culture) and, special/laboratory culture (shaking culture, submerged culture, surface liquid culture and continuous/repeated batch culture). The prospects for herbal biotechnology regarding drug discovery using C. militaris delivering what it has promised are high, as the technology is now extremely more powerful than before. This study chiefly highlights the medicinal uses of the mushroom C. militaris including its culture techniques, also aiming to draw sufficient attention of the researchers to the frontier research needs in this context.  相似文献   
96.
Variations in the sugar, organic acid, and amino acid composition of table grape berries were determined in three successive years in 129 grape cultivars. Three regional groups were represented among these cultivars; European, North American, and Japanese. All cultivars are conserved at the Fukuoka Agricultural Research Center in Japan. Three representative ripe average-sized bunches were selected from one vine per cultivar. Ripeness was judged by visual observation of seed color change to dark brown, without senescence of berry tissue. Soluble solids content (SSC) was weakly correlated with other berry traits, but strongly correlated with total sugar content. Genotypic variance (σ g 2) was significant for all berry traits, especially for α ratio (sugar composition) and γ ratio (amino acid composition). The yearly effect (σ y 2) was significant for SSC, total sugar content, and total amino acid content but not for α ratio, titratable acidity, β ratio (organic acid composition) and γ ratio. Repeatabilities over the 3 years were very high for α ratio and γ ratio, while they were low for SSC, total sugar content, titratable acidity, β ratio, and amino acid content. Correlation coefficients between the values of each individual year and the 3-year mean were relatively high for the α ratio and γ ratio. We highlight the varietal differences in the α ratio and γ ratio because of the low environmental variation. Two types of grape were distinguished on the basis of sugar composition: hexose accumulators (α ratio ≥ 0.81) and sucrose accumulators (α ratio ≤ 0.80). The hexose- and sucrose-accumulating traits were related to genetic or regional differences. Cultivars were classified into five types on the basis of the γ ratio. Like the α ratio, variation in the γ ratio is closely related to cultivar parentage and regional differences. Vitis vinifera cultivars exhibited a skewed distribution with a γ ratio below 1.0 because they contain low levels of sweet amino acids. In contrast, the γ ratio frequently exceeded 1.5 in American hybrid cultivars because they contain high levels of sweet amino acids.  相似文献   
97.
We evaluated the behavior of skipjack (Katsuwonus pelamis), yellowfin (Thunnus albacares) and bigeye tuna (T. obesus) associated with drifting fish aggregating devices (FADs) in the equatorial central Pacific Ocean. A total of 30 skipjack [34.5–65.0 cm in fork length (FL)], 43 yellowfin (31.6–93.5 cm FL) and 32 bigeye tuna (33.5–85.5 cm FL) were tagged with coded transmitters and released near two drifting FADs. At one of the two FADs, we successfully monitored the behavior of all three species simultaneously. Several individuals remained around the same FAD for 10 or more days. Occasional excursions from the FAD were observed for all three species, some of which occurred concurrently for multiple individuals. The detection rate was higher during the daytime than the nighttime for all the species, and the detection rate for bigeye tuna was higher than for yellowfin or skipjack tuna. The swimming depth was deeper during the daytime than nighttime for all species. The fish usually remained shallower than 100 m, but occasionally dived to around 150 m or deeper, most often for bigeye and yellowfin tuna during the daytime. The swimming depth for skipjack tuna was shallower than that for bigeye and yellowfin tuna, although the difference was not large, and is probably not sufficient to allow the selective harvest of skipjack and yellowfin tuna by the purse seine fishery. From the detection rate of the signals, bigeye tuna is considered to be more vulnerable to the FAD sets than yellowfin and skipjack tuna.  相似文献   
98.
99.
The systemic activity of simeconazole (RS-2-(4-fluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-3-trimethylsilylpropan-2-ol) and a number of its derivatives in plants has been investigated to establish which portion of the structure of the molecule contributes to this outstanding activity. The results revealed that the hydroxyl group of the simeconazole moiety is essential for vapour-phase activity and translocation from roots of the compound. They showed that the presence of a fluorine atom in the structure was not indispensable for vapour-phase activity or translocation from roots, although the fluorine atom contributed to these systemic movements. In addition, it was found that the fungicidal activity of simeconazole against Rhizoctonia solani Kühn and Blumeria graminis DC fsp hordei Marchal is potentiated by the fluorine atom, since the activity of a compound which lacked fluorine in the 4-position of the phenyl ring was inferior to that of simeconazole. A compound in which the silicon atom of simeconazole was replaced by a carbon atom showed lower antifungal activity than simeconazole, while phytotoxicity was caused in rice plants by soil drench of the compound. Therefore, the silicon atom of simeconazole may contribute to its selectivity between fungi and plants.  相似文献   
100.
Testis size, seminiferous tubules and plasma testosterone concentrations showed conspicuous annual changes in Sika deer of Hokkaido, Japan. The onset of the spermatogenic process occurred in July or August. Spermatogenic activity had already reached its height in late October, at the beginning of the rutting season, and had begun to decline in late December. Spermatogenesis had stopped in February or March. Plasma testosterone concentrations showed very high levels in late October and early November, but was almost at the basal level in February, March, June and December. The wide individual variation of the plasma levels in October suggest pulsatile secretions of testosterone.  相似文献   
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