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991.
Infertility is well-established harmful effect in chronic alcoholism and so far, there is no effective treatment for this condition. The study was conducted to determine the effects of alpha tocopherol on ethanol induced testicular injuries in male albino rats of Wistar strain. Five groups (n=6) of animals were used. Group I served as control. Group II received daily 1.6g ethanol/kg body weight/day for 4 weeks orally. Group III received 1.6g ethanol+80mg alpha tocopherol/kg body weight/day for four weeks orally. Group IV received 1.6g ethanol/kg body weight for/day 4 weeks and followed by 80mg alpha tocopherol/kg body weight/day for four weeks orally. Group V received 1.6g ethanol/kg body weight/day orally for 4 weeks, followed by 4 weeks abstinence. Twently-four hours after the last treatment the rats were sacrificed using anesthetic ether. Testes were removed and used for the estimation of extent of lipid peroxidation and tissue levels of antioxidants and steroidogenic enzymes. Alpha tocopherol treatment increased the activities of testicularΔ 5, 3β-HSD. Moreover, the treatment was also associated with significant decrease in testicular oxidative stress. Ethanol-induced oxidative stress and decreased steroidogenesis can be reversed by treatment with alpha tocopherol.  相似文献   
992.
任何一个复杂的问题都是近乎无数的事实和关系的组合。商业行为尤其受到方方面面的影响,包括过去的、非逻辑的和不可知的事物的影响。这种复杂性又因目标不同与服务于各种各样的顾客的需要而更加盘根错节,而顾客的许多目标不得不经过权衡后放弃。在这样复杂的条件下解决问题需要井井有条的、系统的方法以试图优化最后的决定。  相似文献   
993.
994.
It is shown that a p+q node graph Gc representation can be drawn for a chessboard C(p,q) i.e. an array of p rows and q columns. It is shown further that the coefficients of the rook polynomial for C(p,q) correspond 1:1 inversely with the coefficients of the chromatic polynomial for Gc written in factorial form.  相似文献   
995.
Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis specially tubercular in initial stages.  相似文献   
996.
For some 300 years the modelling of uncertainty in the sciences has been totally dominated by probabilistic methods. Now, following major criticism of the theoretical foundations of probability theory, other approaches to dealing with uncertainty are being explored.  相似文献   
997.
998.
In response to both problematic and extant gaps in Bachelor??s degree completion rates, this mixed methods study investigated whether a theoretically based undergraduate course intervention measurably contributed to participants?? competence as self-regulated learners. Respective quantitative and qualitative analyses of data collected from two samples showed that intervention participants experienced growth in the targeted self-regulatory constructs. Moreover, differential effects by race/ethnicity and gender were not observed. We conclude with a discussion of this study??s implications for institutions of higher education, pertinent considerations in designing and implementing this self-regulated learning intervention, and a review of the literature on effective practices for doing so.  相似文献   
999.

Purpose

Preschooler instruction for speech sound awareness typically teaches a progression of speech units from sentences to phonemes, ending at simple first phoneme activities. This study investigates the effects of teaching advanced tasks of phoneme blending and segmenting with and without the larger speech unit of the syllable.

Method

Thirty-nine 4-5-year-old typically developing children received twice-weekly small-group instruction in three conditions: two weeks of syllable tasks then four weeks of multiple phoneme tasks (SP), four weeks of multiple phoneme tasks only (MP), or an active control condition of first phoneme instruction (FP).

Results

The conditions SP and MP showed large significant gains on blending and segmenting and no significant differences on first phoneme isolating compared to the FP condition. A comparison of SP and MP did not show significant differences on phoneme blending and segmenting, but SP showed significantly more confusion during early sessions of phoneme instruction.

Conclusion

This preliminary evidence suggests that preschoolers can improve understanding of phoneme blending and segmenting, without first being taught syllable blending and segmenting, and with no negative effects on first sound awareness. These findings support a more efficient way of teaching preschoolers awareness of the individual sounds of speech. Replication with a larger sample, including children at-risk for literacy difficulties, is recommended before firm conclusions should be drawn.  相似文献   
1000.
P. D. Anoop 《Resonance》2011,16(1):29-37
This article deals with the timekeepers of the past, the sundials. Apart from discussing the structure of a few common sundials, we point out the reasons for the variation between sundial time and the time shown by mechanical timekeepers.  相似文献   
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