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The isolation of (+)-uleine (1) and (+)-demethoxyaspidospermine (2) from the bark of Plumeria lancifolia is reported along with (1)H- and (13)C-NMR data. 相似文献
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D. E. Hudson M. D. Volz B. B. DePhillips Gene A. Mathia Frank Haynes N. A. Wynn Allen E. Abrahams Lewis A. Schaper Paul H. Orr Earl C. Yaeger Combs Joseph Robert L. Mercer T. O. Diener W. B. Raymer R. P. Singh T. J. Morris F. E. Manzer J. A. Frank Otto E. Schultz J. E. Huguelet D. Corsini G. F. Stallknecht J. J. Pavek P. Jatala P. R. Rowe S. J. Turner S. S. Leach Raymon E. Webb D. R. Douglas 《American Journal of Potato Research》1975,52(8):239-248
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Summary Several types of outcrossing mechanisms in cowpeas are observed in breeding plots at IITA. Two of these have been studied. One is genetic male sterility controlled by the simple recessive conditions of a gene designated as ms
2
ms
2. The other is mechanical male sterility involving petals constricted in such a way as to provide an opening for stigma and style to emerge at an early, pre-receptive stage of development; while simultaneously restricting stamen development. It is also inherited as a recessive character with the gene symbol designation of Cp-as normal and cp cp as constricted petal. The flower structure is unique and is easily recognized in large populations. Because fruit set is extremely poor it appears less promising than the genetic male sterility at present. 相似文献
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Alvarado-Esquivel C Liesenfeld O Márquez-Conde JA Cisneros-Camacho A Estrada-Martínez S Martínez-García SA González-Herrera A García-Corral N 《Zoonoses and public health》2008,55(6):306-312
Municipal waste is a potential source of infection for Toxoplasma gondii as it may contain contaminated meat with parasite tissue cysts and cat excrement with parasite oocysts. Therefore, we sought to determine the prevalence of T. gondii infection and associated characteristics in two populations exposed to municipal solid waste in Durango, Mexico. Ninety waste pickers and 83 waste workers of Durango City, Mexico were examined for T. gondii infection. They were tested for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. In addition, socio-demographic and behavioural characteristics from each participant were obtained. Nineteen (21.1%) of the 90 waste pickers and seven (8.4%) of the 83 waste workers were positive for anti-T. gondii IgG antibodies. The difference in prevalence among the groups was statistically significant (P =0.03). Waste pickers aged 31-50 years showed a significantly higher prevalence (40.9%) than waste workers of the same age group (2.9%, P < 0.001). Anti-T. gondii IgM antibodies were found in two (2.2%) of the waste pickers but in none of the waste workers. The seroprevalence of T. gondii was significantly higher in workers of the waste transfer station (25.0%) than in drivers or helpers of waste vehicles (2.5%) (P =0.03). Multivariate analysis showed that T. gondii infection was associated with consuming food found in the garbage [adjusted odds ratio (OR) = 4.4; 95% confidence interval (CI) 1.6-11.8] and with lack of education (adjusted OR = 3.2; 95% CI 1.1-8.8). From this study, we conclude: (i) waste pickers may represent a risk group for T. gondii infection; (ii) lack of education might be a contributing factor for T. gondii infection; (iii) the higher the exposure to garbage, the higher the seroprevalence of T. gondii infection; (iv) Eating food products from the garbage may represent an important route for T. gondii infection. 相似文献