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11.
Dietary spice components ofCurcuma longa andAbroma augusta have been screened for their protective effect against reactive oxygen species induced lipid peroxidation. They have been found to be efficient antioxidant when administered in combination. The purpose of the study was to investigate the effect of oral administration (300mg/Kg) of the aqueous extract of turmeric whose active ingredient isCurcumin andAbromine powder as a hypoglycemic agent mixed with diet. The effect of this aqueous extract on blood glucose, lipid peroxidation (LPO) and the antioxidant defense system in rat tissues like liver, lung, kidney and brain was studied for 8 weeks in streptozotocin induced diabetic rats. The administration of an aqueous extract of turmeric and abromine powder resulted in a significant reduction in blood glucose and an increase in total haemoglobin. The aqueous extract also resulted in decreased free radical formation in the tissues studied. The decrease in thiobarbituric acid reactive substances (TBARS) and increase in reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) clearly showed the antioxidant property of the mixture. It is suggested that these changes initially counteract the oxidative stress in diabetes however, a gradual decrease in the antioxidative process may be one of the factors which results in chronic diabetes. These results indicate that the mixture of the two plants have shown antidiabetic activity and also reduced oxidative stress in diabetes. A combination ofAbroma augusta and Curcuma longa also restored the other general parameters in diabetic animals. The results were statistically analyzed and indicated that combination of herbal extracts showed better efficacy as compared to individual herbal plant extracts used.  相似文献   
12.
This study evaluated the effects of comorbid disorders of diabetes and hyperthyroidism in the adult male mice. In total, 32 ICR strain mice were equally distributed into four groups: control (C), diabetic (D), diabetic-plushyperthyroid (DH), and hyperthyroid (H). Mice allocated for diabetes received a single intraperitoneal injection of streptozotocin (STZ) at 200 mg/kg body weight. At the onset of diabetes, one group of mice was concomitantly injected levothyroxine (LT4; 0.3 mg/kg body weight) and the other set of animals received the same treatment independently on a daily basis. The body weight, as well as the testicular and epididymal weights, was reduced markedly in D and DH mice. Higher trends of blood glucose levels were seen in the DH group, in comparison to euthyroid diabetic mice. Thyroid hormones could exert a transient effect on blood glucose homeostasis by altering the serum blood glucose level in diabetic patients. Histomorphometric analysis showed increased luminal sizes of seminiferous tubules, along with decreased epithelial height and atrophic changes in germinal stem cells in the testis of DH and H mice. Caput epididymis of DH mice showed extensive compaction of principal cells, loss of stereocilia, lipid vacuolization, and inflammatory infiltrations; however, damaged tubular integrity, packed clear cells, exfoliated cells, and round spermatids were profoundly noticed in the cauda epididymis. Hyperthyroidism elevated the serum testosterone levels in H and DH mice and produced critical damages to the histoarchitecture of the epididymis. Collectively, this experiment endeavored to mimic the polyglandular autoimmune syndrome, which will be helpful to better understand the reasons for male infertility in diabetic-cum-hyperthyroid patients.  相似文献   
13.
Vitamin B12 is an important coordination compound in biology. It is an interesting biomolecule in the sense that no other vitamin contains a metal ion. This is the only naturally occurring organometallic compound found in biology. An intriguing aspect of vitamin B12 is the great stability of the metal-carbon bond. A great deal of new and interesting inorganic chemistry has been uncovered while studying systems pertinent to B12. In this article some salient features of this unique molecule (B12) and its model compounds are presented.  相似文献   
14.
This study reports on the algebraic generalization strategies used by elementary and middle/high school pre-service mathematics teachers in Kuwait. They were presented with 9 tasks that involved linear, exponential, and quadratic situations. The results showed that these pre-service teachers had difficulty in generalizing algebraic rules in all 3 types of tasks. The most difficult problems were those involving exponents; they seemed to confuse exponential growth with the multiplication of n. Although they used several strategies such as explicit, recursive, and chunking, they tended to rely on explicit reasoning. They saw the explicit rule as a quick and easy rule to be used. In order to improve students’ understanding of algebraic reasoning, we must improve the understating of generalization. Teachers’ programs should put more emphasis on the type of content that teachers need to learn rather than on how much mathematics credits teachers need.  相似文献   
15.
采用Chebyshev配置点法研究平行平板间的导电流体在外加横向磁场作用下的动力稳定性. 通过求解广义Orr-Sommerfeld方程的特征值问题,利用QZ法获取中性曲线,详细分析时间模式下磁流体线性稳定性,研究磁场Hartmann数、Reynolds数、波数和增长率对稳定性的作用.  相似文献   
16.
Silver carp, Hypopthalmichthys molitrix is one of the most economically valuable fish species in Bangladesh. However, its production is often hindered by parasite-induced mortality. The present study reports the intensity of parasitic infestation in 216 specimens of H. molitrix collected from different fish markets in Rajshahi City, Bangladesh. Nine different parasite species (Trichodina pediculatus, Dactylogyrus vastator, Ichthyophthirius multifilis, Gyrodactylus elegans, Lernaea sp., Apiosoma sp., Myxobolus rohitae, Camallanus ophiocephali, and Pallisentis ophiocephali) were recovered from the gill, skin, stomach, and intestine of host fish. The highest level of infection was observed for host skin, while lower levels were observed for host gill, stomach, and intestine. The results also revealed that the intensity of parasite infection in different organs of H. molitrix varied with the season. In particular, the highest levels of infection were recorded during the winter period (November-February), when fish are most susceptible to parasites. The findings of the study will help in the management and conservation of H. molitrix.  相似文献   
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18.
This paper applies and extends Valsiner’s ‘zone theory’ (zones of free movement and promoted actions) through an examination of an intervention to establish inquiry communities in primary mathematics classrooms. Valsiner’s zone theory, in a classroom setting, views students’ freedom of choice of action and thought as mediated by the teacher. The extension of this theory adds that teachers’ freedom of choice of action and thought is mediated by ‘significant others’ and also by the actions of students with new freedoms. The paper presents necessary theoretical constructs and provides extracts from lessons and from teacher-teacher collaboration to illustrate the theoretical extension.  相似文献   
19.
K. Hussain Reddy 《Resonance》2011,16(12):1273-1283
Vitamin B12 is an important coordination compound in biology. It is an interesting biomolecule in the sense that no other vitamin contains a metal ion. This is the only naturally occurring organometallic compound found in biology. An intriguing aspect of vitamin B12 is the great stability of the metal-carbon bond. A great deal of new and interesting inorganic chemistry has been uncovered while studying systems pertinent to B12. In this article some salient features of this unique molecule (B12) and its model compounds are presented.  相似文献   
20.
This research documents Kuwaiti eighth grade students’ performance in recognizing reasonable answers and the strategies they used to determine reasonableness. The results from over 200 eighth grade students show they were generally unable to recognize reasonable answers. Students’ performance was consistently low across all three number domains (whole numbers, fractions, and decimals). There was no significant difference in students’ performance on items that focused on the practicality of the answers or on items that focused on the relationships of numbers and the effect of operations, or on both. Interview data revealed that 35% of the students’ strategies were derived from two criteria for judging answers for reasonableness: the relationships of numbers and the effect of operations, and the practicality of the answers. They used strategies such as estimation, numerical benchmarks, real-world benchmarks, and applied their understanding of the meaning of operations. However, over 60% of the students’ strategies were procedurally driven. That is, they relied on algorithmic techniques such as carrying out paper-and-pencil procedures. Additionally, some of the students’ strategies reflected misunderstandings of how and when to apply certain procedures. Given these findings, mathematics education in Kuwait should shift the emphasis from paper-and-pencil procedures and provide systematic attention to the development of number sense and computational estimation so Kuwaiti students will be more adept at recognizing reasonable answers.  相似文献   
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