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991.
Background
Abscission is the regulated dropping of plant organs, such as leaves or flower petals. This process involves a break down of the cell wall between layers of cells in the abscission zone, causing the organ to become detached. The model plant Arabidopsis thaliana undergoes floral organ abscission. Various experimental methods have been used to study Arabidopsis floral organ abscission, including measuring the petal breakstrength, or the amount of force required to pull a petal from the receptacle. Petal breakstrength provides a quantitative insight into the physical integrity of the petal abscission zone. 相似文献992.
Relationship between DNA ploidy and proliferative cell nuclear antigen index in canine hemangiopericytoma. 总被引:2,自引:0,他引:2
Seong-Kwi Kang Nam-Yong Park Ho-Sung Cho Sung-Shik Shin Mun-Il Kang Sang-Ki Kim Changbaig Hyun In-Chul Park Jong-Tack Kim Cheol Jeong Sung-Hee Park Su-Jin Park Jae-Ho Jeong You-Jung Kim Kenji Ochiai Takashi Umemura Kyoung-Oh Cho 《Journal of veterinary diagnostic investigation》2006,18(2):211-214
The mitotic index is reported to be correlated with recurrence, mean patient survival, and metastasis of canine hemangiopericytoma (CHP). However, to the authors' knowledge, studies investigating the parameters that can predict recurrence or metastasis of CHP with low mitotic index have not been done. To evaluate growth kinetics of CHP with low mitotic index, a retrospective analysis of the proliferative activity by antiproliferative cell nuclear antigen monoclonal antibody and DNA contents by flow cytometry (FCM) was performed with 21 formalin-fixed and paraffin-embedded CHP samples. Of the 21 tumors evaluated by FCM, 6 (26.6%) were aneuploid tumors, and 15 (71.4%) were diploid tumors. There was significant correlation between the PCNA index and ploidy pattern. The diploid group had 39.1 +/- 9.2 PCNA index, whereas the aneuploid group's proliferative cell nuclear antigen (PCNA) index was 63.1 +/- 8.2. The diploid group had mean mitotic index value of 1.140 +/- 0.855, and the aneuploid group had a mean value of 1.067 +/- 0.767. From these results, the CHP samples with low mitotic index were classified into either the aneuploid group with higher PCNA index or the diploid group with lower PCNA index, suggesting that DNA ploidy and proliferative activity may give an indication about malignancy of CHPs with a low mitotic index. 相似文献
993.
Evaluation of concurrent shedding of bovine coronavirus via the respiratory tract and enteric route in feedlot cattle 总被引:4,自引:0,他引:4
Cho KO Hoet AE Loerch SC Wittum TE Saif LJ 《American journal of veterinary research》2001,62(9):1436-1441
OBJECTIVE: To assess the relationship between shedding of bovine coronavirus (BCV) via the respiratory tract and enteric routes and the association with weight gain in feedlot cattle. ANIMALS: 56 crossbred steers. PROCEDURES: Paired fecal samples and nasal swab specimens were obtained and were tested for BCV, using antigen-capture ELISA. Paired serum samples obtained were tested for antibodies to BCV, using antibody-detection ELISA. Information was collected on weight gain, clinical signs, and treatments for enteric and respiratory tract disease during the study period. RESULTS: Number of samples positive for bovine respiratory coronavirus (BRCV) or bovine enteric coro navirus (BECV) was 37/224 (17%) and 48/223 (22%), respectively. Some cattle (25/46, 45%) shed BECV and BRCV. There were 25/29 (86%) cattle positive for BECV that shed BRCV, but only 1/27 (4%) cattle negative to BECV shed BRCV. Twenty-seven of 48 (56%) paired nasal swab specimens and fecal samples positive for BECV were positive for BRCV. In contrast, only 10/175 (6%) paired nasal swab specimens and fecal samples negative for BECV were positive for BRCV. Only shedding of BECV was associated with significantly reduced weight gain. Seroconversion to BCV during the 21 days after arrival was detected in 95% of the cattle tested. CONCLUSIONS AND CLINICAL IMPLICATIONS: Feedlot cattle infected with BCV after transport shed BCV from the respiratory tract and in the feces. Fecal shedding of BCV was associated with significantly reduced weight gain. Developing appropriate control measures for BCV infections could help reduce the decreased weight gain observed among infected feedlot cattle. 相似文献
994.
Khurana HK Cho IK Shim JY Li QX Jun S 《Journal of agricultural and food chemistry》2008,56(3):778-783
Aspartame is a low-calorie sweetener commonly used in soft drinks; however, the maximum usage dose is limited by the U.S. Food and Drug Administration. Fourier transform infrared (FTIR) spectroscopy with attenuated total reflectance sampling accessory and partial least-squares regression (PLS) was used for rapid determination of aspartame in soft drinks. On the basis of spectral characterization, the highest R2 value, and lowest PRESS value, the spectral region between 1600 and 1900 cm(-1) was selected for quantitative estimation of aspartame. The potential of FTIR spectroscopy for aspartame quantification was examined and validated by the conventional HPLC method. Using the FTIR method, aspartame contents in four selected carbonated diet soft drinks were found to average from 0.43 to 0.50 mg/mL with prediction errors ranging from 2.4 to 5.7% when compared with HPLC measurements. The developed method also showed a high degree of accuracy because real samples were used for calibration, thus minimizing potential interference errors. The FTIR method developed can be suitably used for routine quality control analysis of aspartame in the beverage-manufacturing sector. 相似文献
995.
Yong-Jin Park Anupam Dixit Kyung-Ho Ma Ju-Kyung Lee Myoung-Hee Lee Chan-Sik Chung Miyuki Nitta Kazutoshi Okuno Tae-San Kim Eun-Gi Cho V. Ramanatha Rao 《Genetic Resources and Crop Evolution》2008,55(4):523-535
The present study demonstrates utilization of 11 microsatellite markers to explore genetic diversity held in Perilla frutescens (L.) Britt. landrace accessions growing on farms in different parts of Korea and Japan and to assess their genetic relationships.
All microsatellite loci were polymorphic and produced a total of 96 alleles ranging from 4 to 20, with an average of 8.7 alleles
per locus. Of the 96 alleles found, a total of 15 unique landrace-specific alleles were observed at 9 different loci. The
locus GBPFM203 provided the highest number of alleles (20), of which five were unique and each specific to a particular landrace
accession. The occurrence of unique, accession-specific alleles presented molecular evidence for the generation of new alleles
within on-farm collection of Perilla. The mean values of observed (H
O) and expected heterozygosity (H
E) were 0.39 and 0.68, respectively, indicating a considerable amount of polymorphism within this collection. A genetic distance-based
phylogeny grouped the two Perilla varieties, var. frutescens and var. crispa (Thunb.) Decne into two distinct groups. Accessions belonging to var. frutescens could also be divided into two subgroups at a close genetic distance (GD = 0.432). The overall clustering pattern did not
strictly follow the grouping of accessions according to their geographic origins. These observations are indicative of extensive
germplasm exchange among farms from different geographical regions. The genetic similarity observed among the Perilla landraces may be useful for future Perilla crop variety identification, conservation, and improvement programs. 相似文献
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