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31.
A highly selective enzyme-linked immunosorbent assay (ELISA) has been developed for the quantitative detection of the Cry1Ac protein expressed in transgenic cotton. Two Cry1Ac-specific monoclonal antibodies (MAb), Kbt and 158E6, were developed and selected to form a sandwich format ELISA. The MAb Kbt was used as a capture antibody, and 158E6 was conjugated with horseradish peroxidase and served as a detection antibody. The assay was optimized and validated with different cotton matrices. Tissues were extracted with phosphate-buffered saline containing 0.05% Tween 20 and 1% polyvinylpyrrolidone. The extract was then treated with trypsin to truncate full-length Cry1Ac into the core toxin for quantitation. The resulting assay has good accuracy and precision with a validated limit of quantitation ranging from 0.1 to 0.375 mug/g dry weight of cotton tissues. This assay is highly specific for Cry1Ac protein and has no cross-reactivity with the nontarget proteins tested such as Cry1Ab and Cry1F. 相似文献
32.
ABSTRACT Fusarium oxysporum f. sp. lactucae, causal agent of Fusarium wilt of lettuce, is a serious pathogen recently reported in Arizona. Sequence analysis of the mitochondrial small subunit (mtSSU), translation elongation factor 1-alpha (EF-1alpha) gene, and the nuclear ribosomal DNA intergenic spacer (IGS) region was conducted to resolve relationships among f. sp. lactucae isolates, F. oxysporum isolates from other hosts, and local non-pathogenic isolates. Analysis of mtSSU sequences provided limited phylogenetic resolution and did not differentiate the lactucae isolates from 13 other F. oxysporum isolates. Analysis of EF-1alpha sequences resulted in moderate resolution, grouping seven formae speciales with the lactucae isolates. Analysis of the IGS region revealed numerous sequence polymorphisms among F. oxysporum formae speciales consisting of insertions, deletions, and single nucleotide transitions and substitutions. Repeat sequence analysis revealed several duplicated subrepeat units that were distributed across much of the region. Based on analysis of the IGS sequence data, lactucae race 1 isolates resolved as a monophyletic group with three other formae speciales of F. oxysporum. In all analyses, lactucae race 2 isolates composed a separate lineage that was phylo-genetically distinct and distantly related to the lactucae race 1 isolates. 相似文献
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Anthony Claes Barry A. Ball Cynthia J. Corbin Alan J. Conley 《Journal of Equine Veterinary Science》2014
Cryptorchidism is a developmental disorder which can be diagnosed by a variety of different tests. Still, equine field veterinarians often rely on endocrine markers to detect retained testicular tissue. This report describes the value of anti-Müllerian hormone (AMH) as a diagnostic marker for cryptorchidism in three stallions suspected of cryptorchidism, with equivalent serum testosterone concentrations. A single measurement of AMH identified cryptorchidism, with inconclusive testosterone concentrations as either gelding or stallion. Furthermore, a human chorionic gonadotropin (hCG) stimulation test or surgery was performed to support the diagnostic value of AMH. To conclude, the endocrine panel for cryptorchidism should be expanded to include determination of serum AMH, as this determination can increase the diagnostic accuracy of a single blood sample. 相似文献
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Sydney HughesKatheryn Cerny BS MS Juliana CamposMats Troedsson DVM PhD ACT Barry BallEdward Squires MS PhD ACT 《Journal of Equine Veterinary Science》2014
Equine chorionic gonadotropin (eCG), obtained from pregnant mares, is used for assisted reproductive technologies in laboratory rodents and livestock. The objective of the present study was to use equine follicle-stimulating hormone (eFSH) to increase the incidence of twin pregnancies, through multiple ovulations, and increase eCG. Nineteen light horse–type mares were enrolled in the study. The control group (n = 9) was bred with fresh or cooled semen and given human chorionic gonadotropin (hCG) at the time of breeding. The second group (n = 10) was given 12.5 mg of eFSH intramuscularly twice a day beginning 5–7 days after ovulation. Prostaglandin F2α was administered intramuscularly the second day of eFSH treatment. Treatment with eFSH continued until follicles were >35 mm in diameter, and mares were then given no treatment for 36 hours. The mares were then bred with fresh or cooled semen from the same stallion as the control group and given hCG. Blood samples were taken weekly from day 35 to day 105 after ovulation. Serum concentration of eCG was obtained, and data were analyzed with multivariate analysis using the mixed procedure. Significance was set at P < .05. Data were combined for all mares carrying twins and compared with those carrying singletons. The group of mares carrying twins had higher peak concentrations of eCG and higher values for area under the curve compared with mares carrying singletons (P < .05). These results suggest inducing twins could be a method used to increase eCG production. 相似文献
37.
Blaise Ratcliffe Foster J. Hart Jaroslav Klápště Barry Jaquish Shawn D. Mansfield Yousry A. El-Kassaby 《Annals of Forest Science》2014,71(3):415-424
Context
Wood quality traits are important to balance the negative decline of wood quality associated with selection for growth attributes in gymnosperm breeding programs. Obtaining wood quality estimates quickly is crucial for successful incorporation in breeding programs.Aims
The aims of this paper are to: (1) Estimate genetic and phenotypic correlations between growth and wood quality attributes, (2) Estimate heritability of the studied traits, and (3) Assess the accuracy of in situ non-destructive tools as a representative of actual wood density.Methods
Wood density (X-ray densitometry), tree height, diameter, volume, resistance drilling, acoustic velocity, and dynamic modulus of elasticity were estimated, along with their genetic parameters, for 1,200, 20-year-old trees from 25 open-pollinated families.Results
Individual tree level heritabilities for non-destructive evaluation attributes were moderate ( $ {\widehat{h}}_i^2=0.37-0.42 $ ), wood density and growth traits were lower ( $ {\widehat{h}}_i^2=0.23-0.35 $ ). Favorable genetic and phenotypic correlations between growth traits, wood density, and non-destructive evaluation traits were observed. A perfect genetic correlation was found between resistance drilling and wood density (r G ?=?1.00?±?0.07), while acoustic velocity and dynamic modulus of elasticity showed weaker genetic correlations with wood density (r G ?=?0.25?±?0.24;?0.46?±?0.21, respectively).Conclusion
This study confirmed that resistance drilling is a reliable predictor of wood density in western larch, while the weak genetic correlations displayed by acoustic velocity and dynamic modulus of elasticity suggest limited dependability for their use as fast in situ wood density assessment methods in this species. 相似文献38.
Mark D. Needham Jerry J. Vaske Doug Whittaker Maureen P. Donnelly 《Human Dimensions of Wildlife》2014,19(3):288-299
Recreationists who encounter more people than their normative tolerance for seeing others usually feel more crowded than those encountering fewer than their norm. This research note extends this observation–norm–evaluation relationship (e.g., encounter–norm–crowding) to other evaluations and indicators. Data were from a survey of anglers on the Gulkana National Wild River in Alaska (n = 288). Respondents who encountered more people than their norm felt more crowded than those encountering fewer than their norm. When impacts from other social indicators (e.g., camping within sight or sound of other groups, fishing area competition) exceeded user norms, crowding was higher and satisfaction with overall trip quality was lower than for those experiencing less than their norms. When impacts from resource indicators (e.g., litter, impacted campsites) exceeded norms, satisfaction with both environmental quality and trip quality were lower than for those experiencing less than their norms. The encounter–norm– crowding generalization, therefore, extended to other indicators and evaluations. 相似文献
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Nicole L. Vollmer Patricia E. Rosel Keith D. Mullin Lori H. Schwacke Lance P. Garrison Brian C. Balmer Kevin Barry Anthony Martinez Brian M. Quigley Carrie Sinclair Todd R. Speakman Jesse Wicker Lynsey Wilcox Eric S. Zolman 《水产资源保护:海洋与淡水生态系统》2021,31(10):2951-2966
- Population structure of highly mobile marine organisms can be complex and difficult to study, but it is important to understand how populations partition themselves within their environment for accurate assessment of both natural and anthropogenic impacts and successful management. The 2010 Deepwater Horizon oil spill negatively impacted common bottlenose dolphins (Tursiops truncatus) within Mississippi Sound and the surrounding north central Gulf of Mexico (GOMx); however, little was known about their underlying population structure in these waters. Thus, it was unclear how many demographically independent populations were affected by the spill.
- Common bottlenose dolphin samples were collected throughout inshore waters of Mississippi Sound and coastal waters of the north-central GOMx. Mitochondrial DNA control region sequence data and 19 nuclear microsatellite loci were analysed to determine how many populations are present and characterize their range throughout these waters.
- Bayesian clustering and migration analyses identified two genetically distinct and demographically independent populations: one predominantly inhabiting Mississippi Sound and adjacent coastal waters, and a second population extending generally from offshore of Mobile Bay, Alabama, east along the Florida Panhandle. Neither of these populations align with the currently delineated management stocks previously used to estimate impacts from the oil spill on common bottlenose dolphins in this portion of the GOMx.
- These results suggest that revisions may be necessary so that management stocks accurately represent the demographically independent populations present in these waters. Furthermore, better comprehension of underlying population structure will enhance impact assessments on common bottlenose dolphins and provide more appropriate baseline data to support future restoration and conservation objectives.