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31.
A new PCR/RFLP method is presented to identify all described alleles involved in resistance at the Ester locus in the mosquito Culex pipiens. The efficiency of this method as well as its advantages compared with the traditional identification technique (starch gel electrophoresis) have been tested in four natural samples from France, Tunisia and California. This simple and fast molecular test is a very convenient tool for studies in field populations and laboratory strains. © 2000 Society of Chemical Industry  相似文献   
32.
This study describes the clinical, immunologic, genetic, and pathologic features of Irish Wolfhounds with rhinitis/bronchopneumonia syndrome. The dogs examined were from Belgium, The Netherlands, UK, Canada, Germany, and Switzerland. Signs included transient to persistent mucoid or mucopurulent rhinorrhea, cough, and respiratory dyspnea. Radiographic, rhinoscopic, and bronchoscopic findings were variable. Analysis of ciliary ultrastructure was performed in 5 affected dogs, but no characteristic primary ciliary defects (primary ciliary dyskinesia) were detected. Serum and bronchoalveolar lavage fluid (BALF) concentrations of IgA, IgG, and IgM were determined in some affected dogs and clinically normal Irish Wolfhounds. Serum IgA concentration was below the reference range in 5 of 8 affected dogs tested, whereas BALF IgA concentration was above the normal range in 2 affected adult dogs. The CD4 to CD8 lymphocyte subset ratio (CD4:CD8) in peripheral blood was tested in 3 affected dogs and was within the normal range. BALF CD4:CD8 was tested in 1 affected dog and was higher than the normal range. Decreased neutrophil phagocytosis was observed in 1 of the 4 dogs tested. Analysis of pedigrees of the Belgian, Canadian, German, and Swiss dogs revealed common ancestry, suggesting a heritable syndrome.  相似文献   
33.
The physicochemical characteristics of bananas grown at two different altitudes (L: 50 m and H: 300 m) in Martinique, French West Indies (FWI) were compared at four harvest stages with the aim of potentially promoting mountain bananas – which differ from current standard bananas – or export to the European market. At an equivalent harvest stage, highland (H) bananas were significantly thicker in diameter (grade), denser and firmer than lowland (L) bananas. After ripening, H bananas were significantly firmer and their peel was harder as compared to L bananas. Their dry matter and dry soluble extract contents and citrate concentrations were significantly higher than noted in L bananas. P contents were significantly higher in L bananas whereas Zn contents were higher in H bananas. A principle component analysis differentiated H and L bananas on the basis of their physicochemical characteristics. It was found that the “altitude” factor had a more marked effect than the “harvest stage” factor on the physicochemical characteristics of ripe fruit.  相似文献   
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In the dogfish sharkSqualus acanthias different germ cell stages are topographically segregated within the testis. Using this species we have developed methods for the isolation and culture of Sertoli cells from premeiotic, meiotic and post-meiotic stages of spermatogenesis and present preliminary evidence for stage-dependent variations in cell morphology and behavior, thymidine incorporation, protein synthesis and steroidogenesis. The goal of future studies is to determine how maturational changes are regulated in Sertoli cells and, in turn, to elucidate Sertoli cell-germ cell interactions.  相似文献   
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Journal of Crop Science and Biotechnology - To evaluate the combined effect of different agricultural practices on photosynthetic nitrogen and water-use efficiency, winter wheat was grown in the...  相似文献   
39.
From germination until anthesis or flower bud abortion, seedlings from ‘Sonia’ × ‘Hadley’ were grown in both a greenhouse (full daylight, 20° C) and a growth room (8 Wm?2, 8 h, 20°C) of the IVT-phytotron. Plastochron was an external indication of the stage of flower differentiation. Flower differentiation in flowering and aborting seedlings ran parallel up to petal-segregation. Flower differentiation in aborting seedlings did not proceed beyond stamen formation. Early abortion, which also caused absence of the upper leaf, occurred without, later abortion with, an abscission zone in the flowerstalk.  相似文献   
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