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981.
The population dynamics of Heterodera glycines as influenced by alachlor, fenamiphos, and ethoprop alone and in herbicide-nematicide combinations were studied in the field. Numbers of H. glycines juveniles and eggs were higher at midseason and harvest where nematicides were applied. Fenamiphos alone or in combination with alachlor provided better control of H. glycines and greater seed yields than treatments with ethoprop. Numbers of H. glycines eggs at harvest in 1980 were positively correlated with numbers of juveniles at planting in 1981 and negatively related to seed yield in 1981.  相似文献   
982.
G E Tranter 《Bio Systems》1987,20(1):37-48
The violation of parity by the weak interactions ensures that enantiomeric chiral molecules have inequivalent energies, one being inherently stabilized with respect to the other. These parity-violating energy differences have been calculated for a number of fundamental biomolecules including a series of alpha-amino acids, polypeptide structures, and a representative of the sugar series together with its variation over a possible prebiotic reaction path leading to alpha-amino acids. In each case the natural enantiomer found in terrestrial biochemistry was shown to be intrinsically stabilized and preferred over its unnatural enantiomer. The significance of these results in accounting for the prebiotic origins of the terrestrial biomolecular homochirality is discussed and the possible consequences of parity-violating energy differences in mineral catalysts during the prebiotic era considered.  相似文献   
983.
984.
985.
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   
986.
987.
988.
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   
989.
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   
990.
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   
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