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991.
Calyptospora n. g. was erected for Eimeria funduli because the sporocyst of that species lacks Stieda and sub-Stieda bodies, has a veil supported by sporopodia, and has an anterior apical opening. A suture may be present, but it does not completely divide the sporocyst into two valves. Because C. funduli has an obligatory invertebrate intermediate host, we established Calyptosporidae n. fam. to accommodate Calyptospora and tentatively to accept Goussia. A new subgenus, Plagula, is erected for species of Goussia with a sporocystic veil not supported by sporopodia. We consider the family more primitive than Eimeriidae, Sarcocystidae, and possibly Lankesterellidae.  相似文献   
992.
993.
994.
The finger and palmar prints of 60 women with breast carcinoma were studied. The results were compared with two groups of healthy women, the first consisted of old women and the second of young women. The dermatoglyphics seem to be of little use in the diagnosis of cancers of ectodermic origin. Supported by M.P.I. 60%, 1983  相似文献   
995.
D. Higuet 《Genetica》1986,69(2):107-110
Under the hypothesis that heterosis may be due to a greater flexibility of heterozygotes, we have measured in a Drosophila melanogaster strain, polymorphic at the sepia locus, female productivity of the homozygotes and heterozygotes for this locus, in constant as well as in fluctuating temperature conditions. It was expected that the heterozygotes, being more flexible, would be better adapted to a fluctuating temperature than to a constant one. At none of the three temperature regimes (18°C; 28°C; 18–28°C) heterosis or rather overdominance was evident. However, fluctuating temperature results reveal a greater performance of all genotypes than constant-temperature ones do.  相似文献   
996.
Nuclear genes that appear to encode both cytosolic and plastid isozymes of phosphoglucose isomerase (PGI), an essential glycolytic enzyme, have been isolated from three diploid species of the annual wild flower genus Clarkia (Onagraceae). The genes do not contain introns and are expressed to varying degrees in Escherichia coli when cloned in either Charon 35 phage or pUC plasmid vectors. The PGI proteins synthesized in E. coli form dimers, are catalytically active, and their electrophoretic mobilities are similar to those of appropriate Clarkia PGIs. The nucleotide sequence of a gene encoding a plastid isozyme of C. unguiculata is described.  相似文献   
997.
TUCKER  D. J. 《Annals of botany》1980,45(5):555-560
The rogue tomato differs from the normal plant in that it exhibitsa lesser degree of apical dominance. Grafting techniques andmeasurements of the endogenous levels of growth substances inthe two types have been used in order to establish whether thisdifference is due to an altered hormonal balance in the roguetype. The results suggest that root-produced cytokinins play no rolein the control of apical dominance in the tomato plant, andthat lateral bud out-growth is influenced by a balance betweenapically-produced auxin, abscisic acid produced at the sitesof bud development and cytokinins synthesized within the budsthemselves. Lycopersicon esculentum L., tomato, apical dominance, abscisic acid, auxins, cytokinins, growth regulation  相似文献   
998.
α-Synuclein (α-syn) amyloid filaments are the major ultrastructural component of pathological inclusions that define several neurodegenerative disorders, including Parkinson disease and other disorders that are collectively termed synucleinopathies. Since the aggregation of α-syn is associated with the etiology of these diseases, defining the molecular elements that influence this process may have important therapeutics implication. The deletions of major portions of the hydrophobic region of α-syn (Δ74-79 and Δ71-82) impair the ability to form amyloid. However, mutating residue E83 to an A restored the ability of these proteins to form amyloid. Additionally supporting an inhibitory role of residue E83 on amyloid formation, mutating this residue to an A enhanced amyloid formation in the presence of small molecule inhibitors, such as dopamine and EGCG. Our data, therefore, suggest that the presence and placement of the highly charged E83 residue plays a significant inhibitory role in α-syn amyloid formation and these findings provide important insights in the planning of therapeutic agents that may be capable of preventing α-syn amyloid formation.  相似文献   
999.
Inheritance of barley nuclear genes responsible for various morphological marker traits was studied in hybrid populations F2 and Fa. Nine marker genes showed deviation from Mendelian monogenic inheritance depending on the cross direction and maternal cytoplasm. Segregation biases to both recessive mutant and dominant normal phenotypes were observed. Mechanisms of the segregation bias related to cytoplasm substitution in iso- and alloplasmic lines are discussed.  相似文献   
1000.
The composition of the phospholipid-bound fatty acids in the spermatozoa of the turkey, Meleagris gallopavo, and fowl, Gallus domesticus, was studied. The types of fatty acids were similar in the two birds. The ratio of polyunsaturated : saturated fatty acids was generally low but slightly higher in the turkey than in the fowl. The significance of the findings in relation to the origin of the semen collected in these gallinaceous birds and the greater difficulty of freezing turkey spermatozoa was discussed.  相似文献   
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