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681.
Electron microscopy of the cells of the follicle duct of Triops cancriformis shows that the follicular ducts are lined by a single-layered epithelium which also produces the eggshell material. The cytoplasm is rich in rough endoplasmic reticulum that synthesizes the eggshell material which subsequently aggregates into preformed vacuoles. Newly formed spheres of eggshell material are then excreted into the lumen. At the end of vitellogenesis the oocytes descend toward the longitudinal oviduct and pass through the eggshell material which fills the follicle ducts. The production of the eggshell and its chemical composition in some Phyllopoda are compared. The paper discusses the relationship between the eggshell construction and the reproductive biology of the population. 相似文献
682.
Franca Dagna Bricarelli M. Fraccaro J. Lindsten U. Müller P. Baggio Laura Doria Lamba Carbone A. Hjerpe F. Lindgren Antonia Mayerová H. Ringertz E. M. Ritzén D. C. Rovetta C. Sicchero U. Wolf 《Human genetics》1981,57(1):15-22
Summary Three families with infants affected with campomelic dysplasia, a genetically determined mesenchymal disease frequently associated with sex reversal were studied. Two XY famales with ovarian gonadal differentiation and typical clinical features of campomelic dysplasia could be tested for H-Y antigen and were found to be H-Y negative. 相似文献
683.
Roberto Alves de Lima Nidia Cavalcanti Franca Pedro Diaz Diaz Otto R. Gottlieb 《Phytochemistry》1975,14(8):1831-1833
The trunk wood of Iryanthera coriacea Ducke (Myristicaceae) contains six compounds which belong to the recently discovered 1,3-diarylpropane type of flavonoids, 1-(2-hydroxy-4-methoxyphenyl)-3-(3,4-methylenedioxyphenyl)-propane, 1-(2,4-dihydroxyphenyl)-3-(3,4-methylenedioxyphenyl)-propane, 1-(4-methoxyphenyl)-3-(2-hydroxy-4,5-methylenedioxyphenyl)-propane, 1-(4-hydroxy-2-methoxy-phenyl)-3-(4-hydroxy-3-methoxyphenyl)-propane, 1-(2,4-dihydroxyphenyl)-3-(2-methoxy-4,5-methylene-dioxyphenyl)-propane, 1-(2,4-dihydroxy-3,5-methylphenyl)-3-(2-hydroxy-4,5-methylenedioxyphenyl)-propane. 相似文献
684.
Kathlyn Vasconcelos Gevú Maura Da Cunha Claudia Franca Barros Sabrina Magna Pereira Helena Regina Pinto Lima 《Plant Systematics and Evolution》2014,300(5):1089-1098
Xylem structural characteristics are rarely used to separate tribes. This study aims to characterize the morphology of subterranean organs and determine both the occurrence and distribution of the vessel elements in ten species, belonging to Alpinieae and Zingibereae tribes. Species were from protected areas in the Brazilian Atlantic Rain Forest or from private cultivation areas. Roots and rhizomes processing followed both light and scanning electron microscopy procedures. According to morphological and anatomical characteristics, Euclidean distances among taxa were calculated, resulting in a dendrogram based on the unweighted pair group method with arithmetic mean (UPGMA) clustering. Despite our results indicating a similarity among all the species studied, they could be segregated by using qualitative and special metabolites characters in both the rhizome and the root. Vessel elements were found to be confined to the roots, presenting several basal characters in most of species, except for Alpinia purpurata and Etlingera species. 相似文献
685.
Arduino Oratore Grazia Banchelli Franca Buffoni Stefania Sabatini Bruno Mondovi Alessandro Finazzi-Agro 《Biochemical and biophysical research communications》1981,98(4):1002-1007
Antibodies have been raised against purified beef plasma, pig plasma and pig kidney amine oxidases. Despite the overall similarity, no immunological cross-reactivity was observed among these enzymes, even using a very sensitive light-scattering technique. The presence of substrate affects the rate of the reaction between kidney diamine oxidase and its antibody, but not that of other amine oxidases. 相似文献
686.
Chiarella Sforza Maria Morini Claudia Dolci Laura Vizzotto Franca Carandente 《Chronobiology international》1990,7(5):377-382
Orcadian rhythmicity of the structural morphometric model of rat endocrine pancreas has been studied in 24 Wistar female rats, four months old, kept in LD 12:12. The following parameters were evaluated: the volume fractions of nucleus and cytoplasm of exocrine cells, the size distribution and number in unit tissue volume of acinar cell nuclei, the mean nuclear diameter, the shape coefficient of glandular acini (that is the ratio acinar area/perimeter2 which indicates the shifting of structures from circularity). A statistically significant circadian rhythm was demonstrated for the shape coefficient of glandular acini. Results obtained in the present experiment are compared with data recorded in a previous study. 相似文献
687.
Marisa Berti Roberto Scotti Franca Ripamonti Vittorio Arioli 《Current microbiology》1979,2(4):223-225
The activity of the combination rifampin plus trimethoprim againstHaemophilus influenzae was studied from the point of view of synergism, bactericidal activity, and inhibition of the selection of rifampin-resistant
cells. At concentrations of the two drugs that are easily attainable in human serum after oral treatment with 600 mg of rifampin
plus 160 mg of trimethoprim, the combination acted synergistically on all of the strains tested, was remarkably bactericidal,
and inhibited the selection of rifampin-resistant cells. 相似文献
688.