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11.
The aim of this study was to investigate the ethanolic leaf extract of Trianthema portulacastrum L. (Family: Aizoaceae) on aflatoxin induced hepatic damage in rats. Aflatoxin intoxication in rats significantly (p < 0.001) elevated the levels of serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), and total bilirubin, which indicated acute hepatocellular damage and biliary obstruction. Ethanolic leaf extract of T. portulacastrum showed dose dependent decrease in the levels of SGPT, SGOT, ALP and total bilirubin. Minimum effective dose of extract was found to be 100 mg/kg body weight. Results obtained from histopathological studies also supported hepatoprotective activity against aflatoxin-induced hepatotoxicity. Thus the study demonstrates that T. portulacastrum possess antihepatotoxic effect against aflatoxin.  相似文献   
12.
Science & Education - In this study, we report the results of the content analysis of preservice middle school science teachers’ own written science storybooks and middle school female...  相似文献   
13.
In the present study, oxidative stress and lymphocytic DNA damage in both pre-op and post-op benign prostrate hyperplasia (BPH) patients with age >50 years was evaluated and compared with normal healthy subjects (controls- without any evidence of disease) of the same sex and age group. From December 2007 to November 2009, oxidative stress in 45 BPH patients were evaluated both before (pre-op patients) and after 7 days of surgery (post-op patients) in terms of measurements of plasma levels of (1) various anti-oxidative enzymes, (2) non-enzymatic antioxidants and (3) malondialdehyde which is a product of lipid peroxidation. The lymphocyte DNA damage was also evaluated by single cell alkaline gel electrophoresis in terms of tail length migration in these patients. These values were compared with their respective control subjects of similar sex and age group. The activities of antioxidant enzymes and the levels of antioxidant, reduced glutathione were found significantly decreased (p < 0.05) in serum samples of pre-operative group of BPH patients as compared to the controls. These altered parameters increased significantly (p < 0.05) and returned to their near normal control values, but not up to baseline values, in post operative patients i.e. after the cancer load was decreased by surgery. Lymphocytic DNA damage was found to be significantly increased in pre-op group as compared to controls and was reduced after surgery in post-op group. The present study therefore, shows significantly increased levels of oxidative stress and DNA damage in BPH patients which were reduced after removal of tumour load. Thus oxidative damage plays an important role in prostate tumourogenesis and timely management of oxidative stress can be of importance in preventing the occurrence of BPH.  相似文献   
14.
Recent educational policies, national reports, and voluminous literature stress that critical thinking (CT) is an essential skill in any stage of schooling for producing critical thinkers and ensuring better learning. The importance of teaching CT has been raised in teacher education programmes because students are supposed to teach this skill in schools in the future. This study therefore assesses the effects of a CT-based pedagogical course on student teachers’ content knowledge and CT disposition. A pre-test–post-test experimental study was carried out in a vocational pre-service teacher education programme in Turkey. Although the students who were exposed to CT-based instruction showed better progress in both academic achievement and CT disposition than in traditional instruction, this result was not statistically significant according to the Mixed Factorial ANOVA and ANCOVA results.  相似文献   
15.
A quasi-experimental research design was used to investigate the effectiveness of synthetic phonics in the development of early reading skills among struggling young English as a second language (ESL) readers in a rural school. The pretest and posttest, adapted from the Phonological Awareness Literacy Screening (PALS) for Preschool Students and Grades 1 to 3 tests, assessed children’s early reading skills. A semi-structured interview was used to gather information. The findings indicated that the performance of students in the experimental group in decoding was significantly higher in the posttest, where t(39) = 31.441, p < .00005. Likewise, in comprehension, the experimental group achieved significantly higher scores in the posttest, where t(39) = 15.322, p < .00005. There was a significant difference in the achievement between the two groups, where t(78) = 31.010, p < .00005. This indicates that synthetic phonics could be effective in developing early reading skills for struggling readers.  相似文献   
16.
This study explored third-grade elementary students' conceptions of nature of science (NOS) over the course of an entire school year as they participated in explicit-reflective science instruction. The Views of NOS-D (VNOS-D) was administered pre instruction, during mid-school year, and at the end of the school year to track growth in understanding over time. The Young Children's Views of Science was used to describe how students conversed about NOS among themselves. All science lessons were videotaped, student work collected, and a researcher log was maintained. Data were analyzed by a team of researchers who sorted the students into low-, medium-, and high-achieving levels of NOS understandings based on VNOS-D scores and classwork. Three representative students were selected as case studies to provide an in-depth picture of how instruction worked differentially and how understandings changed for the three levels of students. Three different learning trajectories were developed from the data describing the differences among understandings for the low-, medium-, and high-achieving students. The low-achieving student could discuss NOS ideas, the medium-achieving student discussed and wrote about NOS ideas, the high-achieving student discussed, wrote, and raised questions about NOS ideas.  相似文献   
17.
This longitudinal study examined growth in the English productive vocabularies of bilingual and monolingual children between ages 24 and 36 months and explored the utility and validity of supplementing parent reports with teacher reports to improve the estimation of children's vocabulary. Low-income, English-speaking and English/Spanish-speaking parents and Early Head Start and Head Start program teachers completed the MacArthur–Bates Communicative Development Inventory, Words and Sentences for 85 children. Results indicate faster growth rates for monolingual than for bilingual children and larger vocabularies for bilingual children who spoke mostly English than mostly Spanish at home. Parent–teacher composite reports, like parent reports, significantly related to children's directly assessed productive vocabulary at ages 30 and 36 months, but parent reports fit the model better. Implications for vocabulary assessment are discussed.  相似文献   
18.
The serum and hepatic enzymes of rats were studied after exposed to country made liquor (CML) along with two chelating agents (glutathione and Selenium). There was a significant increase in several serum enzyme levels (viz., aspartate transaminase, alanine transaminase, alkaline phosphatase, sorbitol dehydrogenase, glutamate dehydrogenase, bilirubin) and decrease in various hepatic enzymes (Succinic dehydrogenase, Glucose 6-phosphatase, 5'Nucleotiease, Acid phosphatase, Acid ribonuclease, Cytochrome P-450) due to repeated administration of CML (2ml/100g of body weight). Results of this study revealed that the GSH and Se could give a significant protective action in serum and hepatic enzymes of CML exposed rats.  相似文献   
19.

Introduction:

Preanalytical errors, along the process from the beginning of test requests to the admissions of the specimens to the laboratory, cause the rejection of samples. The aim of this study was to better explain the reasons of rejected samples, regarding to their rates in certain test groups in our laboratory.

Materials and methods:

This preliminary study was designed on the rejected samples in one-year period, based on the rates and types of inappropriateness. Test requests and blood samples of clinical chemistry, immunoassay, hematology, glycated hemoglobin, coagulation and erythrocyte sedimentation rate test units were evaluated. Types of inappropriateness were evaluated as follows: improperly labelled samples, hemolysed, clotted specimen, insufficient volume of specimen and total request errors.

Results:

A total of 5,183,582 test requests from 1,035,743 blood collection tubes were considered. The total rejection rate was 0.65 %. The rejection rate of coagulation group was significantly higher (2.28%) than the other test groups (P < 0.001) including insufficient volume of specimen error rate as 1.38%. Rejection rates of hemolysis, clotted specimen and insufficient volume of sample error were found to be 8%, 24% and 34%, respectively. Total request errors, particularly, for unintelligible requests were 32% of the total for inpatients.

Conclusions:

The errors were especially attributable to unintelligible requests of inappropriate test requests, improperly labelled samples for inpatients and blood drawing errors especially due to insufficient volume of specimens in a coagulation test group. Further studies should be performed after corrective and preventive actions to detect a possible decrease in rejecting samples.  相似文献   
20.
Four hundred and fifty‐one students' attitudes towards science were investigated. Two types of instruments (questionnaire and Attitude Scale) were used to collect the data. The results show that the students in general hold a favourable attitude towards science; male students have more positive attitude towards science than female students; the type of school (science‐school, single‐sex school or general secondary school) attended have an effect on the students' attitudes to science. The low enrollment in science is not due to the lack of interest or negative attitudes to the subject but may be due to some other variables that need to be investigated.  相似文献   
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