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We investigated the synthesis and herbicidal activity of 23 toxoflavin analogs, 1a–w, in which aromatic rings (R) were introduced into the C-3 position. In paddy field conditions, 1k (R=2-CF3–C6H4) and 1w (R=2-thienyl) showed excellent herbicidal activity. Under upland field conditions, we found that toxoflavin analogs 1a (R=C6H5), 1n (R=2-CH3O–C6H4), and 1p (R=4-CH3O–C6H4) exhibited wide herbicidal spectrum against Echinochloa crus-galli (L) var. crus-galli (ECHCG), Chenopodium album, and Amaranthus viridis (AMAVI). The analog with the 2-fluoro group on benzene ring 1b also showed high herbicidal activity against both ECHCG and AMAVI.  相似文献   
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Five primer/probe sets to identify the tomato wilt pathogen, Fusarium oxysporum f. sp. lycopersici (FOL), and its three races selectively were designed based on the rDNA-intergenic spacer and avirulence genes. Real-time PCR using genomic DNA from mycelia and soil DNA with the primer/probe sets allowed the successful identification of FOL and its races.  相似文献   
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The relationship between pulmonary hypertension and lesions was examined in 41 dogs infested naturally with heartworms, which consisted of 28 cases with pulmonary heartworm disease and 13 cases with caval syndrome. Pulmonary arterial pressure (PAP) was measured before and 1 or 7 days after heartworm removal with a flexible alligator forceps. In these dogs, lesions were examined after the last measurement of PAP. The mean PAP was 28.2 +/- 16.0 mmHg (10.9 to 81.4 mmHg in range) at post-removal phase. Pulmonary arterial intimal lesions, pulmonary thromboemboli, pneumonic lesions, tricuspid valvular lesions and mitral valvular lesions were macroscopically recognized in 95, 59, 39, 54 and 56% of cases, respectively. These lesions were classified by severity and the relationship with PAP was examined by the multiple correlation analysis. The multiple coefficient correlation was found the highest between PAP and thromboemboli, followed by mitral valvular lesion, tricuspid valvular lesion, and pneumonic lesion. There was no significant correlation between PAP and intimal lesions. The coefficient of determination showed the highest value in thromboemboli when one variable was used, and increased only very slightly when a variable of thromboemboli was added to those of other lesions. The cases with high PAP had fresh thromboemboli in large pulmonary arteries. From these evidences, it was concluded that thromboemboli following natural death of heartworm was the most important factor causing an increase in PAP and developing clinical signs in canine heartworm disease.  相似文献   
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Three-dimensional reconstruction of the equine ovary   总被引:1,自引:0,他引:1  
The equine ovary has a very unique structure in terms of its extreme large size, the presence of the ovulation fossa and the inverted location of its cortex and medulla. In the previous study, it was recognized that the application of three-dimensional internal structure microscopy (3D-ISM) to observe the mare ovary is very effective. Three-dimensional reconstruction of serially sliced images made by 3D-ISM was successful in this study with the aid of the sophisticated image processing technique. The rotation of the reconstructed ovary has been carried out with and without the application of the transparency technique in the ovarian stromal region. The spatial localization of follicles and corpus luteum was clearly visualized by rotating the reconstructed image of the ovary. The extraction of the images of follicles and corpus luteum was also available and gave a quantifiable understanding of their structure.  相似文献   
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The breeding season was investigated in 174 female cats that were acclimated under a natural photoperiod, and determined the interval between birth and initial estrus (puberty) was determined in 125 cats. Although the breeding season differed noticeably among individual animals, the mean was 180.4 +/- 3.0 (SE) days between the end of January and the end of July. The interval between birth and first estrus ranged from 181 to 560 days, with a mean of 345.0 +/- 0.9 days. With respect to month of birth, the mean interval was 343.0 +/- 9.5 days in cats born between March and June. Among cats that were born between July and October, the mean intervals were 242.0 +/- 6.3 days in cats that exhibited estrus the year after birth and 519.2 +/- 5.8 days in those that exhibited estrus 2 years after birth.  相似文献   
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