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Sesbania grandiflora (L.) pers (Fabaceae) and Arabidopsis thaliana (L.) (Brassicaceae) were genetically engineered to constitutively express the rabbit cytochrome p450 2E1 enzyme aiming at increasing their activity toward trichloroethylene (TCE) and dichlorodiphenyltrichloroethane (DDT) removal Successful generation of Sesbania and Arabidopsis transgenic plants was verified using p450 2E1 specific PCR and confirmed by western blot analysis. Gas chromatography (GC) analysis revealed that small cuttings of Sesbania and third generation (F3) Arabidopsis transgenic plants exposed to TCE and DDT in small hydroponics' vessels accumulated more TCE and DDT compared to plants transformed with the empty vector. Furthermore, both transgenic plants were more effective in breaking down TCE and DDT with a 2-fold increase in TCE metabolism. Two independent Arabidopsis lines showed that DDT was metabolized about 4-fold higher than that detected in non transformed plants. Similarly, S. grandiflora cuttings removed 51 to 90% of the added DDT compared with only 3% removal in controls transformed with the null vector. Notably, stability of rabbit cytochrome p450 2E1 was confirmed using third generation Arabidopsis plants that displayed higher potential for the removal of two important pollutants, TCE and DDT compared with the controls.  相似文献   
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A new TaqI polymorphism of the complement factor B gene.   总被引:1,自引:0,他引:1       下载免费PDF全文
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The concentrations of free Na+, K+, Ca(+, and Cl(-)in endolymph and perilymph from the inner ear of the oyster toadfish, Opsanus tau, were measured in vivo using double-barreled ion-selective electrodes. Perilymph concentrations were similar to those measured in other species, while endolymph concentrations were similar to those measured previously in elasmobranch fish, though significantly different from concentrations reported in mammals. Perilymph concentrations (mean +/- std. dev.) were as follows: Na+, 129 mmol l(-1) +/- 20; K+, 4.96 mmol l(-1) +/- 2.67; Ca2+, 1.83 mmol l(-1) +/- 0.27; and Cl(-), 171 mmol l(-1) +/- 20. Saccular endolymph concentrations were Na+, 166 mmol l(-1) +/- 22; K+, 51.4 mmol l(-1) +/- 16.7; Ca2+, 2.88 mmol l(-1) +/- 0.27; and Cl(-), 170 mmol l(-1) +/- 12; and semicircular canal (utricular vestibule) endolymph concentrations were Na+, 122 mmol l(-1) +/- 15; K+, 47.7 mmol l(-1) +/- 13.2; Ca2+, 1.78 mmol l(-1) +/- 0.48; Cl(-), 176 mmol l(-1) +/- 27. The relatively high concentrations of Ca2+ and Na+ in the endolymph may have significant implications for the physiological function of the mechanoelectrical transduction channels in the vestibular hair cells of fish compared to those of their mammalian counterparts.  相似文献   
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Data of 56 normal and 9 abnormal estrous cycles were collected from 9 Egyptian buffaloes (Bublus bublis) to describe the follicular growth wave pattern. Heat was checked twice daily while, ovaries were scanned daily to monitor the patterns of follicular waves. Day of ovulation was determined when the largest follicle was replaced by corpus haemorrhgicum (CH). Number of waves/cycle, day of emergence of the follicular wave, characteristics of the dominant follicle and corpus luteum (CL) growth features were monitored. Buffaloes displayed mainly two types of follicular waves; two (46.4%) and three (53.6%). In cycles of three wave pattern, time of emergence of the 1st wave post-heat was longer (P < 0.05) and number of recruited follicles/wave were larger (P < 0.05) compared to the corresponding values of the two wave pattern. Number of recruited follicles in early follicular waves (1st or the 2nd) had larger number (P < 0.05) compared to the subsequent ones. Follicles that reached ovulation in both types of estrous cycle had shorter life-span (P < 0.05) than the previous ones. Life-span of CH, growing and regressed CL were 3.6 ± 0.6, 11.2 ± 0.8 and 4.4 ± 0.5 days, respectively with no difference in both types of follicular wave. Three types of ovarian disorders were observed. Follicular waves and CL growth features showed unique pattern for each individual. These results demonstrate that buffaloes display two main types of follicular waves with dominance of three wave type.  相似文献   
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