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A C Pandey 《Ecotoxicology and environmental safety》1988,15(2):221-225
Histomorphological responses of the ovary of a freshwater percoid fish, Colisa (T.) fasciatus, to endosulfan or thiodan EC 35 treatment, a popular pesticide, have been described. In addition, general behavioral changes of the fishes after treatment have also been recorded. Adult sexually mature females were used in the present study and all fish were in the prespawning phase of the ovarian cycle. The experiment was conducted under natural room temperature and day-night length for 30 days. Experimental fish were maintained in 1 ppm endosulfan solution, which was changed on alternate days after feeding with minced goat liver. Treated fish revealed that (a) the ovarian activity was retarded; (b) the ovarian wall became thicker; (c) the diameter of oogonia and stage I oocytes was not altered but that of stage II and III oocytes was greatly reduced; (d) the percentage of oogonia, stage I, and atretic oocytes increased considerably but that of stage II and III oocytes diminished significantly; and (e) yolk in the stage III oocytes appeared clumped and damaged. 相似文献
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H Pandey 《Journal of tropical pediatrics》1991,37(5):235-239
Integrated Child Development Services (ICDS) is India's most comprehensive programme to increase the survival rate and enhance the health, nutrition, and learning opportunities of pre-school children and their mothers through a package of services. The present study was carried out to measure the impact of the preschool education component of the ICDS on the cognitive development of children in the age group of 3-5 years. The study design used was case/control (ICDS attending children v. Non-ICDS). Results of the study revealed the ICDS Anganwadi attendance had positive influence on the cognitive development of children. The mean cognitive score of the attenders was 40.7 as against a mean score of 30.3 in the case of non-attenders. 相似文献
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Cyclohexanone was condensed with N-hydroxymethyl benzamide in conc. sulphuric acid to give alpha-methyl-benzamido-cyclohexanone (I). The reaction of (I) with thiosemicarbazide in ethanol resulted in alpha-methyl-benzamido-cyclohexanone thiosemicarbazone (II). Condensation of (II) with various aromatic aldehydes in the presence of ethanol afforded alpha-methyl-benzamido-alpha'-substituted-styryl-cyclohexanone thiosemicarbazones (III) in yields ranging from 40 to 50 percent. The compounds exhibited pronounced antiimplantation activity in female albino rats. 相似文献
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A Monte Carlo calculation for the initial electron energy spectra produced in semi-infinite and finite water phantoms irradiated by photons of energies up to 2 MeV and photons from 60Co are presented incorporating successive Compton scattering, photoelectric absorption and Auger effect. The backscattering of photons through the top of the phantom and transmission of photons out of the finite phantom through the sides also are considered. The results are compared with the earlier calculation for infinite water phantom of Turner et al. who assumed that all the photons remained in the water until they were absorbed. It is found that inclusion of backscattering in a semi-infinite phantom yields significantly different results from those of Turner et al. for the infinite phantom. It is also found that backscattering and transmission of the photons through the sides of the finite phantom further alter the initial energy spectra of electrons, as well as the average number of electrons per photon at different photon incident energies. 相似文献
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C McKenzie BAppSc P Megaw BAppSc I Morgan PhD MK Boelen PhD 《Clinical & experimental ophthalmology》1997,25(4):79-81
Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth. 相似文献
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