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1.
Inflammation of the cardiac coronary artery in ICR mice is occasionally observed in toxicity studies; however, this has not been well explored histologically. Herein, we investigated the detailed histology of the associated lesions in 6–8-week-old ICR mice. Coronary artery inflammation in the right ventricular wall was observed in 10 of 142 mice (7.0%). Histopathological examination revealed hypertrophy of the vascular smooth muscle cells and perivascular infiltration of macrophages in mild cases. In moderate to marked cases, single-cell necrosis of vascular smooth muscle cells, hemorrhage of the tunica media, and fibrinoid necrosis of the vessel wall were observed, in addition to the changes seen in mild cases. Electron microscopic examination of moderate cases revealed a discontinuous internal elastic lamina suggestive of rupture, and vascular smooth muscle cells beneath the elastic lamina showed degeneration and necrosis. These findings suggest that the lesions developed as a rupture of the internal elastic lamina and necrosis of vascular smooth muscle cells, while leaked plasma components caused vascular and perivascular inflammation. In ICR mice, dystrophic calcinosis (DCC) is known to occur rarely in the right ventricle. DCC is defined as focal calcification in necrotic myocardial fibers, the pathogenesis of which is considered to involve ectopic calcification. Since calcification was not observed in any part of the heart, including the inflammation region, the pathophysiology of cardiac arterial inflammation seen in our ICR mice was considered to differ from that of DCC.  相似文献   
2.
Innovations in precision agriculture (PA) have created opportunities to achieve a greater understanding of within-field variability. However, PA adoption has been hindered by uncertainty about field-specific performance and return on investment. Uncertainty could be better addressed by using innovative analyses that provide insights into variability among fields and across a region. The objectives of this research were to: (1) generate a within-field soil clay-content variability index (VIc), (2) create a regional-scale growing-season precipitation variability index (VIp), and (3) integrate the soil and weather indices with the USDA NRCS soil erosion vulnerability index (SVI) to produce a final index that incorporated both variability and vulnerability (VVI). The interpretation of the outcomes represented by each objective supports unique decisions that land managers may consider for reducing uncertainty about implementing PA. All indices were derived using publically available information for Missouri, USA. The VIc was the ratio between the maximum and minimum clay content within fields. The VIp was calculated as the standard deviation of the total growing-season precipitation from 2006 to 2015. Significant clustering of VIc and VIp were observed along the Missouri River corridor, northeast and northwest Missouri. Fields with high VVI were mostly in the claypan soil region of northeast Missouri, and along a portion of the Missouri River dominated by loess soils on steep slopes. Southeast Missouri displayed the greatest diversity in soil and weather variability, but had low vulnerability. This research could be used as a decision-support tool to aid producers and PA service and product providers in determining where PA opportunities exist.  相似文献   
3.
It has been suggested that certain morphological traits of Japanese pines function as resistance factors against the pine wood nematode (PWN), Bursaphelenchus xylophilus. The aim of this study was to verify this concept, and to determine the relationships between traits and resistance at both the individual and family levels. Relationships between survival rate and morphological traits of Pinus densiflora and Pinus thunbergii were studied after inoculation with PWN. Morphometric parameters used were height, basal diameter of the axis, and the number of branches from the axis. Three indices of relationships were analysed: (1) among individuals within a family (survival difference between smaller and larger morphometric populations within each family); (2) among individuals (correlation between each morphometric average and survival rate in quintile populations of all subjects within each pine species based on the order of morphometric values); and (3) among families (correlation between each morphometric average and survival rate in the family). Both significant and non-significant differences were detected within a family, indicating a need for macro techniques. Among individuals, a thicker axis and more branches were correlated with increased survival, indicating that they are resistance factors. However, these correlations were not significant among different families. These results indicate that morphological traits cannot be used to evaluate resistance at a family level, even if they are significant at an individual level. Further studies on traits associated with resistance should be conducted at a family rather than an individual level, to breed for Japanese pines with resistance to PWN.
Taro YamanobeEmail:
  相似文献   
4.
For nutritional purposes, a survey of the vitamin B6 levels from a variety of commercial presentations of table olives was carried out, taking into account the three main processing types (Spanish-style, directly brined, and ripe olives). The analysis was performed by HPLC, following the official French method for vitamin B6 determination in foodstuffs. In-house validation data for two commercial table olives showed that the method precision was good (coefficient of variation <6%) and recovery was quantitative (104% on average). There was a wide range of values for vitamin B6 in table olives (0–69.3 μg/100 g edible portion). The highest mean content was found in directly brined olives (33.9 μg/100 g edible portion) followed by Spanish-style (14.4 μg/100 g) and ripe olives (4.3 μg/100 g). On average, samples of the Gordal and Carrasqueña cultivars showed the highest vitamin B6 content in the case of Spanish-style olives, but in directly brined olives as well as in ripe olives the effect of cultivar was not statistically significant (p?相似文献   
5.
To determine how stock abundance fluctuations of walleye pollock Theragra chalcogramma are related to variations in reproductive characteristics, the length at 50% maturity of the fish sampled off the Pacific coast of northern Japan from 1990 to 1999 was examined. In both sexes, the fish density increased, and the body length of age-3-5 fish decreased, but the condition factor and the age at 50% maturity showed no clear trend during this period. Male length at 50% maturity decreased, while value for females showed no clear trend. In both sexes, significant negative correlations were found between density index (combined age-3-5) and each body length at age-3-5. Significant positive correlations were seen between each body length at age-3-5 and length at 50% maturity in males. Positive correlation between body length at age-5 and length at 50% maturity was significant in females from 1990 to 1999, except for the samples in 1998. We suggest that the fish density might affect the length at maturity in males and possibly also in females.  相似文献   
6.
Effects of sodium nitroprusside (SNP; nitric oxide donor) treatments on enhancement of secondary metabolites production, oxidative stress mediators (\(\mathrm{O}_{2}^{-}\)) accumulation and antioxidant defense enzymes of Potato Spunta Sp. suspension culture cells elicited by a fungal extract from phytophthora infestans mycelium. The obtained data confirmed the significant increase in various oxidative burst (super oxide anion, hydrogen peroxide and total glutathione) contents. The administration of various NO concentrations strongly decreased hydrogen peroxide concentration and superoxide anion levels. Moreover, the SNP treatments regulate elicitor-induced activation of phenylalanine ammonium-lyase and total soluble phenols accumulation. The highest concentrations of NO donor sodium nitroprusside potentiated elicitor-induced H2O2 production. On the other hand, the lowest H2O2 contents coincided with elicitation regulated various activities of enzymes superoxide-dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and Phenyl alanine ammonia lyase (PAL) activity, the decrease in H2O2 concentration was probably due to a direct reduction interaction of NO-H2O2. On the other hand, the addition of these previous NO treatments affects mRNA peroxidase gene expression using RT-PCR techniques. In general, the addition of lower concentrations of nitric oxide reduce the mRNA peroxidase activity on contrary, the higher concentrations induced the mRNA peroxidase activity, which induce the hypersensitive reactions against fungus infection.  相似文献   
7.
8.
The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   
9.
The root parameters of forest trees can be indicators of a changing environment. We summarize the results of root studies with regard to the effects of acidifying pollutants, especially soil acidification and aluminum toxicity, on various root parameters of Japanese forest trees under experimentally controlled conditions. All root parameters such as biomass, morphology, nutritional status, and physiology can be regarded as indicators, because, under laboratory conditions, root responses occur prior to the responses in the aboveground parts. However, considering the conditions of forest sites, the nutritional status and physiological changes are better indicators of soil acidification and Al stress than the biomass and morphological response. The currently available data suggest that the most important indicator is the Ca/Al molar ratio in roots of Japanese tree species. In order to predict and detect the initial effects of soil acidification, we postulate that the specific root response to the Ca/Al molar ratio of tree roots should be considered as a parameter for use in long-term forest monitoring sites.  相似文献   
10.
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