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991.
Endogenous oestrogens are thought to be involved in breast cancer, but few studies could show the direct relationship between hormones and pathological process of the disease. In the present study, oestradiol was estimated in the serum of pre-and postmenopausal breast cancer patients along with normal healthy controls and patients with carcinoma of the uterine cervix which is not dependent on oestrogens. Premenopausal patients with breast cancer showed higher levels of oestradiol as compared to premenopausal control women as well as cervical cancer patients. Whereas, no statistically significant differences were observed in serum oestradiol levels amongst postmenopausal groups of breast cancer, cervical cancer and normal women. The result of the study reflects the association of oestradiol as well as its difference in the pathological events of pre and postmenopausal breast cancer.  相似文献   
992.
One of the fundamental problems in information science is to distinguish various objects (such as books or journal articles) on the basis of associated values (such as authors and titles). Where the values fail to distinguish two distinct objects we say that the objects are ambigious under the given value assignment. To obtain a measure of ambiguity, it is only necessary to count the number of ways that the objects can be arranged for each set of ambiguous objects, multiply these counts and take logarithms. It is shown that such an approach leads to a measure in the formal sense and that the measure depends only on the definition of equality of values so that it can be simply extended to sets of values and ordered sets of values. It is also shown that it is possible to construct a function of ambiguity that one can call “information” and that the information loss that occurs when distinct values are grouped into equivalence classes (as in the use of search and sort keys) is also a measure. Finally, it is shown that ambiguity and information as here defined are directly related to Shannon's definition of “information” thus tieing this approach to that portion of information theory associated with the derivation of optimal distributions frequently used in information science models.  相似文献   
993.
994.
995.
Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood lipid profile which could promote atherogenesis.  相似文献   
996.
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   
997.
A diverse sample of doctoral students completed an on-line questionnaire assessing their supervisors' academic, personal and autonomy support and their research self-efficacy. The more task-related help and personal support students received, the more positively they evaluated their supervision. The degree to which supervisors encouraged students to think and act autonomously (autonomy support) was not uniquely associated with students' supervision satisfaction but predicted greater research self-efficacy. A combination of high levels of autonomy and academic support was associated with the highest levels of research self-efficacy, whereas when greater levels of personal support were accompanied by low levels of autonomy support, students reported lower research self-efficacy. These results indicate that effective doctoral supervision involves supporting students to voice and act on their own ideas while simultaneously providing guidance on how to complete research tasks.  相似文献   
998.
Although progress has been made, greater efforts are needed to promote faculty diversity at the college and university levels, especially in STEM fields. Thus, it is important to elucidate best practices both for increasing awareness of diversity issues pertaining to higher education and for implementing change. This article focuses on the outcomes of a diversity workshop for college and university faculty hosted by the West Virginia Higher Education Policy Commission, Division of Science and Research. More specifically, it elucidates how participation in the workshop translated into practice at the faculty participants’ home institutions.  相似文献   
999.
This study examines whether levels of father engagement (e.g., verbal stimulation, caregiving, and physical play) vary by race/ethnicity using a model that controls for fathers' human capital, mental health, and family relationships. It also tests whether the models work similarly across race/ethnic groups. Its sample of N=5,089 infants and their families is drawn from the Early Childhood Longitudinal Study - Birth Cohort (ECLS-B). We found that, after including controls, African American and Latino fathers had higher levels of engagement in caregiving and physical play activities than White fathers. There were no differences in verbal stimulation activities across race/ethnicity. Fathers' education (college level) predicted more verbally stimulating activities whereas fathers' report of couple conflict predicted less caregiving and physical play. Although levels of engagement differed across the groups, the overall models did not differ by race/ethnicity, except for physical play. African American mothers who reported high levels of depressive symptoms had partners who engaged in more physical play than White mothers with high levels of depressive symptoms.  相似文献   
1000.
This paper describes the implementation and evaluation for scaling up a comprehensive early childhood teacher professional development program into 11 communities across 2 years with funding through state legislative actions. The comprehensive program had four major components based on results from a previous multi-condition random assignment study across four states. The previous results demonstrated that the most optimum approach for supporting children??s school readiness included: (1) teacher on-line professional development with facilitation, (2) classroom mentoring, (3) implementation of a research-based curriculum, and (4) technology-driven progress monitoring that informed instruction. The comprehensive professional development program was evaluated in a new state program designed to bring childcare, Head Start, and public school pre-kindergarten together into integrated partnerships. In Year 1, 220 teachers serving 3834 children were randomly assigned to either receive the comprehensive program or not. Teachers who served as controls in Year 1 received the program in Year 2, and those who received the program in Year 1 participated for an additional year in Year 2, allowing for examination of the effects of one versus 2 years of participation. The program improved teachers instructional practices relative to controls, and a second year of participation resulted in greater gains in children??s language and literacy. Results support the need for well-integrated, comprehensive professional development for early childhood educators.  相似文献   
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