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1.
Groups of photosensitive, unstimulated or stimulated, male blackheaded buntings were subjected to photoregimes of 15 hr of green light of three intensities and 9 hr of dark per day. In some groups green light was interrupted with 90 min of bright fluorescent light at different times in the subjective day. While gonads did not develop or regressed in some groups, birds in others behaved as if exposed to long daylengths. The results besides suggesting the involvement of endogenous circadian rhythm during initiation and maintenance of gonadal growth indicate that the reproductive rhythms are entrained and induced by environmental photoperiod.  相似文献   
2.
The production of d-aminoacylase by Alcaligenes denitrificans and Alcaligenes faecalis has been studied. The enzyme was inducibly produced and N-acetyl-d-leucine and N-acetyl-d-valine were the most effective inducers. d-methionine, d-valine, d-phenylalamine and d-leucine were produced by the enzymic hydrolysis of the appropriate N-acetyl-d-amino-acids with whole cell biomass. The hydrolysis of N-acetyl-d-methionine by A. denitrificans and N-acetyl-d-valine by A. faecalis was preferential. Maximum yields of d-methionine and d-valine were 94.3 and 84.7% at a specific product formation rate of 20.10 and 19.19 μmol min−1 mg−1 of wet cells at 20 mM substrate concentration and 5 mg ml−1 of cell density.  相似文献   
3.
Five popular but iron-inefficient cultivars were crossed with three efficient genotypes and both parents and F1s were evaluated for iron-efficiency in potted calcareous and noncalcareous soil. The iron-efficient genotypes were dark green or green in both noncalcareous and calcareous soils whereas inefficient types were light green to yellow in calcareous soil. The chlorophyll and active iron (Fe2+) concentration of leaves was less in iron-efficient genotypes compared to efficient types in calcareous soil and reduction of both the parameters from noncalcareous to calcareous soil was considerably high in iron-inefficient lines. There was significant correlation between visual scores, chlorophyll and active iron content. There were no differences among F1s for iron chlorosis and they were all iron-inefficient. The frequency of iron-inefficient plants was higher than the efficient plants in all F2 populations. But most of the productive plants came from iron-efficient segregants indicating strong association between iron-efficiency and productivity. Based on the results selection for iron-efficiency in early generations and extensive evaluation for productivity in advanced generations is suggested for developing varieties for cultivation in calcareous soils.  相似文献   
4.
The short-term and long-term effects of two most commonly used brown and black masheri were studied in Swiss mice and Syrian golden hamsters. In short-term studies, both the types of masheri extracts (ME) at 3/4 LD50 dose given ip did not have any effect on either liver or plasma vitamin C levels (both species). However, a decrease in liver vitamin A was observed only in hamsters injected with black ME. Similar effect was not observed in mice injected with both the types of masheri extracts. In long-term studies, when both the types of masheri were fed through diet at 10% level for 20 months, no effect was observed on hepatic or plasma vitamin C levels in mice (both sexes), while an increase in vitamin C levels was observed in black masheri diet fed hamsters. A depletion in liver vitamin A was observed in hamsters fed both the types of masheri. Such an effect was observed only in black masheri diet fed Swiss mice (both sexes) and brown masheri diet fed Swiss females.  相似文献   
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Adsorption of fungal spores on a synthetic polymer - High Density Polyethylene was successfully achieved using different pretreatments. Sonication of beads followed by ferric nitrate treatment or use of 0.1% tributyrin gave adsorption upto 46%. Use of dichloromethane as a solvent for sonication is recommended for its better performance in reuse studies (upto 5 times without much decrease in activity). 100 g of immobilized biocatabyst in a 7 L Fluidized Bed Bioreactor was found to perform better than shaker flask at a much lower power input.  相似文献   
8.
Changes in peroxidase activity during pregnancy were examined in CD-1 mice. Peroxidase activity was measured with guaiacol as the substrate in uterine extracts of nonpregnant mice and in uterine, placental, and fetal extracts of pregnant mice on days 9, 12, 14, 16, and 18 of gestation. Uterine peroxidase activity in nonpregnant mice was high, but declined logarithmically to only 0.2% by day 18 of pregnancy. In contrast to this decline, a concomitant 50-fold logarithmic increase in fetal peroxidase activity was observed between day 12 and 18. Activity in placental extracts did not change significantly throughout the gestational period examined. These results suggest that membrane bound peroxidase in mouse uterus and fetus undergoes major shifts during pregnancy.  相似文献   
9.
Changes in ovarian follicular kinetics were studied in relation to aging in the Indian skipper frog Rana cyanophlyctis.Age was determined by skeletochronology, by counting the number of growth rings and lines of arrest of growth from the cross sections of 4th phalange of 4th toe. For follicular kinetics study oocytes were counted under binocular using 10% of Bouin’s fixed ovary and they were classified into first growth phase, medium-sized second growth phase, large-sized second growth phase and atretic follicles. Analysis of phalangeal cross sections indicated that frogs ranging 14–54 g in body weight and 4.9–8.9 cm in body size showed 1–7 year rings. Frogs that weighed 14–16 g showed 1 year ring, and contained immature ovaries; those with 18 g body weight had one to two year rings, in which second growth phase oocytes appeared for the first time in the primiparous ovary. Frogs with 20–54 g body weight showed 2–5 year rings in which ovary contained 5–24% of second growth phase oocytes. Further, body weight, body size, ovarian weight, number and size of second growth phase oocytes and total number of oocytes showed a significant (P < 0.05) positive correlation, while, the number of first growth phase and atretic follicles showed a poor correlation with age. The results suggest that in nature, the age of Rana cyanophlyctis ranges between 1–7 years. Phalangeal growth rings are formed annually. Females attain sexual maturity in 2nd year. Frogs with 2–5 years of age may constitute breeding females. Body weight, body size, ovarian mass, number of second growth phase and total oocytes, and egg size increase with age up to 5 years.  相似文献   
10.
Since the positive charge on the lysine residues plays an important role in the receptor recognition ability of oLH, the hormonotoxin has been synthesised with the use of 2-iminothiolane HC1 (2IT) and N-Succinimidyl-3-(2-pyridyldithio)-propionate (SPDP). The oLH activated with 2IT (oLH-10) was then mixed with SPDP activated gelonin (gelonin-30) in order to obtain a oLH-S-S-gelonin hormonotoxin. The conjugation mixture containing hormonotoxin was purified by gel-filtration chromatography according to the molecular weight and a complete physico-chemical, immunochemical and biochemical analysis were performed. The linkage occured through the -NH2 groups of -subunit of oLH as judged from RP-HPLC analysis. A 11 (oLH:gelonin) molar ratio was obtained when determined with the use of several techniques. The hormonotoxins retained substantial receptor binding, steroidogenic activity and immunoreactivity. The competitive displacement analysis indicate that the binding occurs via the hormone part leaving the gelonin free which was probed with the gelonin antibodies. The presently described (C150A-02, C160A-02 and C170A-02) hormonotoxins exhibited higher receptor binding and toxicity to the target cells than the hormonotoxins prepared with the use of SPDP only. Therefore it is concluded that higher receptor binding and cytotoxicity may be due to the retention of positive charge on the lysine residues of oLH which was preserved during the conjugation process.Abbreviations BSA Bovine Serum Albumin - CMC Carboxy methyl Cellulose - DTT Dithiothreitol - DMEM Dulbeco's Modified Eagle's Medium - DTNB Ellman's reagent [5,5-dithio-bis-(2-nitrobenzoic acid)] - EDTA Ethylenediaminetetraacetic acid - FPLC Fast Protein Liquid Chromatography - FCA Freund's Complete Adjuvant - FCS Fetal Calf Serum - Gelonin-30 Gelonin modified by SPDP - GnRH Gonadotropin-Releasing Hormone - Gelonin-SPDP SPDP modified derivative of gelonin - HEPES (N-[2-hydroxyethyl] piperazine-N-[-2-ethanesulphonic acid]) - IFA Incomplete Freund's Adjuvant - 2IT 2-Iminothiolane - IODOGEN 1,3,4,6-tetrachloro 3,6-diphenylglycouril - oLH Ovine Luteinizing Hormone - oLH-SPDP SPDP modified derivative of oLH - oLH-10 oLH modified by 2IT - oLH2IT Molar ratio of oLH and 2IT - PDP 2-Pyridyl-dithiopropionate - PAP Pokeweed Antiviral Protein - RIP Ribosome Inactivating Protein - RP-HPLC Reverse-Phase High Performance Liquid Chromatography - RPMI Roswell Park Memorial Institute - RIA Radioimmunoassay - RRA Radioreceptor Assay - SPDP N-Succinimidyl-3(2-pyridyldithio)propionate - SDS-PAGE Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis - TCA Trichloroacetic acid - TFA Trifluroacetic acid  相似文献   
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