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91.
Antennal responses of male European corn borer moths, Ostrinia nubilalis, to their two pheromone components, (Z)- and (E)-11-tetradecenyl acetates (tda), were studied. The electroantennogram (EAG) response was highest when the ventral side and lowest when the dorsal side of the antenna faced the air stream carrying the chemical stimulus. Repetitive stimulation with one of the isomers resulted in adaptation which affected the amplitude of response in subsequent tests of both (Z)- and (E)-11-tda. This suggested that the receptors for the two tda isomers are either identical or highly interactive. Mixtures of the two pheromone components did not elicit higher responses than the major component, (Z)-11-tda. A significant difference was observed between London and New York strains of this insect in their relative responses to (Z)- and (E)-11-tda. EAG responses of hybrids of these two strains resembled those for the New York strain.  相似文献   
92.
93.
A seroepidemiological survey of varicella was made in the Nagoya area by the neutralization (NT) test. Of 1,473 recorded cases of varicella, 81.4% were under 6 years old and 9.6% were under one year old; of the 168 recorded cases under one year old, about 30% were under 5 months old. Examination of 11 pairs of mother and cord sera and 13 pairs of mother and infant sera showed that transfer of NT antibody was in general good, even in babies that were small for their age or smnall at birth after 28 weeks gestation. The transferred maternal antibody decreased rapidly, becoming undetectable in babies of 4 months old. Then with increase in age the percentgage of seropositive children gradually increased, being 53.3% at 4 to 5 years old, and 100% in those of over 9 years old, with a temporary decrease in young adults in their twenties.  相似文献   
94.
The proton nmr spectra of the synthetic valency hybrids, α2+CN)2, (α+CN)2β2 of hemoglobin A and the natural valency hybrids of the mutant hemoglobins Boston, Iwate and Milwaukee have led to the unambiguous assignment of the two proximal histidyl imidazole exchangeable proton signals at 64 and 76 ppm to individual α and β subunits, respectively. New single non-exchangeable proton resonances detected in the extreme downfield region of the spectra of Hbs Boston and Iwate are tentatively assigned to the coordinated tyrosine of the mutated α chains.  相似文献   
95.
Electron paramagnetic resonance (EPR) spectra of the glycosylated minor hemoglobins A1a-1, A1a-2, A1b and A1c and the major hemoglobin A0 in the nitrosyl form have been obtained in the absence and presence of inositol hexaphosphate. In the absence of inositol hexaphosphate, nitrosyl hemoglobins A1a-1, A1a-2 and A1b exhibited a triplet hyperfine structure centered at g = 2.009 which has been shown to be diagnostic of the low affinity (T) quaternary structure. Addition of inositol hexaphosphate to nitrosyl hemoglobins A0, A1c, A1b and A1a-2 developed a triplet hyperfine structure of the EPR spectra but the magnitude of the hyperfine was decreased in the order of hemoglobins A0, A1c, A1b and A1a-2. However, inositol hexaphosphate had essentially no effect on the EPR spectrum of nitrosyl hemoglobin A1a-1. The present results account qualitatively for the oxygen binding properties of these glycosylated minor hemoglobins in the framework of a two-state allosteric model.  相似文献   
96.
Summary As the hydrolysis of mandarin orange peel with macerating enzyme (40°C, 24 h) produced 0.59 g g–1 reducing sugar per dry peel compared to 0.36 by acid-hydrolysis (15 min at 120°C with 0.8 N H2SO4), the production of single cell protein (SCP) from orange peel was studied mostly using enzymatically hydrolyzed orange peel.When the enzymatically hydrolyzed peel media were used, the utilization efficiency of reducing sugars (%) and the growth yield from reducing sugars (g g–1) were: 63 and 0.51 for Saccharomyces cerevisiae; 56 and 0.48 for Candida utilis; 74 and 0.69 for Debaryomyces hansenii and 64 and 0.70 for Rhodotorula glutinis. SCP production from orange peel by D. hansenii and R. glutinis were further studied. Batch cultures for 24 h at 30°C using 100 g dried orange peel produced 45 g of dried cultivated peel (protein content, 33%) with D. hansenii and 34 g (protein content, 50%) with R. glutinis, and 38 g (protein content, 44%) with a mixture of both yeasts.  相似文献   
97.
Summary Correlated responses to selection for increased growth rate were compared in two mouse populations (M16 and H6) of distinct genetic origin. Traits studied were body composition, feed intake, constituent gains and energetic efficiency. When compared with their respective controls (ICR and C2) at 6 and 9 weeks of age, body weight increased more in M16 (57%and 69 % of the control mean) than in H6 (40 % and 34%). The M16 showed correlated responses in fat percent of 2.6% (P <.05), 8.4% (P <.01) and 11.2% (P <.01) at 3, 6 and 9 weeks, respectively, whereas corresponding values in H6 were –2.4% (P <.05), 3.3% (P <.05) and 2.09 % (P >.05). The correlated responses in fat percent were 2.7 and 4.7 times higher in M16 than H6 at 6 and 9 weeks. The regression of ln fat weight on ln empty body weight was larger in M16 (P <.05) compared to ICR and larger (P <.01) in H6 compared to C2. Both M16 and H8 exhibited positive correlated responses from 3 to 6 weeks of age in feed intake and gain and efficiency in fat, protein, calories and ash; fat and caloric gain and efficiency exhibited higher correlated responses in M16 than H6. During the 6- to 9-week interval, the M16 population continued to evince positive correlated responses in gains and efficiencies of fat, protein and calories, whereas H6 did not. Several possible explanations are presented to account for the differences in correlated responses between the selected populations. Partitioning of correlated response differences between M16 and H6 into average direct and average maternal genetic effects indicated that average direct genetic effects, favoring M16, were responsible for the major difference between the selected populations. Direct heterosis in F1 crosses of the selected populations were generally not significant, although there was a tendency for fat percent and fat weight to show heterosis.Paper No. 4929 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, North Carolina 27607, Animal Research Institute Contribution No. 624 and Agricultural University at Wageningen Contribution No. 654-490-10. The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Experiment Station of the Products named, nor criticism of similar ones not mentioned.On leave from Department of Animal Husbandry, Agricultural University, Wageningen, The Netherlands.On leave from Animal Research Institute, Agriculture Canada, Ottawa, Ontario K1A OC6.  相似文献   
98.
Summary Direct and maternal genetic effects were evaluated for maturing patterns of body weight in mice using a crossfostering design. Crossfostering was performed in one group using dams from populations selected for rapid growth rate (M16 and H6) and their reciprocal F1. crosses. A second crossfostering group consisted of dams from the respective control populations (ICR and C2) and their reciprocal F1. 's. Population differences were partitioned into direct and maternal effects due to genetic origin, correlated selection responses, heterosis and cytoplasmic or sex-linked effects. Degree of maturity was calculated at birth, 12, 21, 31 and 42 days of age by dividing body weight at each age by 63-day weight. Absolute and relative maturing rates were calculated in adjacent age intervals between birth and 63 days. Genetic origin effects (ICR vs. C2; M16 vs. H6) were significant for many maturity traits, with average direct being more important than average maternal genetic effects. In general, correlated responses to selection for maturity traits were larger in the M16 population (M16 vs. ICR) than in the H6 population (H6 vs. C2) and correlated responses in average direct effects were larger than average maternal effects. Positive correlated responses in average direct effects were found for relative maturing rates at all ages and for absolute maturing rates from 31 to 63 days. Apparent correlated responses in degree of maturity were negative for M16 and H6. However, further analysis suggested that the correlated response for degree of maturity in H6 may be positive at later ages and negative at earlier ages. Direct and maternal heterosis for degree of maturity was positive in the selected and control crosses. Absolute and relative maturing rates showed positive heterosis initially, followed by negative heterosis. Reciprocal differences due to the cytoplasm or sex-linkage were not important for patterns of maturity.Paper No. 5244 the Journal Series of the North Carolina Agricultural Experiment Station, Ealeigh, Animal Research Institute Contribution No. 683 and Agricultural University at Wageningen Contribution No. 654–490–12On leave from the Animal Research Institute, Agriculture Canada at Ottawa, OntarioOn leave from the Department of Animal Husbandry, Agricultural University at Wagenitgen, the Netherlands  相似文献   
99.
During the course of immunization of (C3H × DBA/2)F1 mice (genotype H-2k/b) with L cell (H-2k/k)/L1210 leukemia cell (H-2d/d) hybrids and L1210 leukemia cells, some of them produced a good titer of anti-self-H-2 (H-2d) antibodies. Antigens recognized by this anti-self-H-2 antiserum were shown to be controlled by the H-2K-IA-IB-IJ-IE subregions of the H-2d but not H-2k nor H-2b haplotypes of parental as well as F1 origins and to have a tissue distribution identical to that of class 1 H-2 (H-2K/D) antigens.  相似文献   
100.
The nuclear restructuring that occurs between insemination and full pronuclear formation in pig eggs is accompanied by posttranslational changes to specific egg proteins. Sperm penetration begins in vitro at 3 hr postinsemination (hpi). By 5 hr, decondensing sperm heads and anaphase II plates are observed in 50% of eggs, and, by 8 hpi, both male and female pronuclei have formed. Three consistent changes to the pattern of newly synthesised proteins are triggered in this period; they affect the 46K, 25K, and 22K polypeptides. Changes are also triggered in the 180-200K polypeptides and in the 14K polypeptides, but these are highly variable. The same changes in the prefertilization pattern were observed when prelabelled eggs were used and new protein synthesis was suppressed. The first and most abrupt change involves the apparent catabolic elimination of a group of 46K unphosphorylated polypeptides (pl 7.3-6.4), whose synthesis was greatest before germinal vesicle breakdown but declined slowly in the final phase of maturation, then declined precipitously after activation. Ageing (beyond maturation) also leads to the disappearance of these polypeptides. The progressive disappearance of a set of 25K polypeptides and the concomitant appearance of a dominant 22K polypeptide is the most characteristic fertilization-induced modification to porcine egg proteins. These modifications begin within 1 hr of sperm penetration or activation, are specific to the pig, and involve heavily phosphorylated polypeptides (25K, pl 6.7-6.0) whose synthesis is begun in the early metaphase I stage. Dual ([35S] and [32P]) labelling, protein blocking experiments, and use of alkaline phosphatase suggest that dephosphorylation selectively affects these 25K polypeptides and is mainly or wholly responsible for converting them (completely within 6 hr) to a single, new (22K, pl 7.6) species that is positively charged. The 25K/22K polypeptide modification has a close temporal relationship with the formation of the male and female pronuclei.  相似文献   
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