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991.
Evaluated, in 2 studies, which of 3 theoretical models best describes the interrelations of causal attributions, causal dimensions, and affective reactions to success and failure. Study 1 used an experimental methodology requiring 99 undergraduates to imagine themselves in different achievement situations, whereas Study 2 involved the investigation of the affective reactions of 161 undergraduates to performance on a midterm examination. Results indicate that causal attributions and causal dimensions had joint and independent effects on affective reactions to success and failure. Implications for a theoretical model of the relation between attribution processes and affect are discussed. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
Chronic myeloid leukemia course was evaluated versus sex in 271 patients. Chronic stage involved more pronounced leukocytosis, thrombocytosis and splenomegaly in females, the latter showing higher susceptibility to anemia. As a result, treatment has to deal with a greater mass of tumor. A relatively longer survival time in males (44 and 42 months, respectively) suggest a higher effectiveness of therapy in such patients. When diagnosed, leukocytosis, thrombocytosis, enhanced splenomegaly and anemia should be regarded as factors of unfavorable prognosis.  相似文献   
993.
Expository Text Comprehension in the Primary Grade Classroom.   总被引:1,自引:0,他引:1  
This study investigates the effectiveness of an instructional program designed to teach 2nd graders how to comprehend compare-contrast expository text. Along with introducing new content (animal classification), the program emphasizes text structure via clue words, a sequence of questions, and a graphic organizer, and via the close analysis of specially constructed exemplar paragraphs. The authors compared the program with (a) more traditional instruction that focused only on the new content and (b) a no instruction control; 128 7- and 8-year-olds participated. Classroom teachers provided the instruction. The program improved students' ability to comprehend compare-contrast texts. Students were able to demonstrate transfer to uninstructed compare-contrast texts though not to text structures other than compare-contrast. Moreover, the text structure instruction did not detract from their ability to learn new content. The results provide evidence, heretofore lacking, that explicit instruction in comprehension is feasible and effective as early as the 2nd grade. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
994.
995.
The capabilities of 1alpha, 25-dihydroxyvitamin D3 (1,25(OH)2D3), and two novel vitamin D analogues, EB1089 and KH1060, to induce the differentiation of two established leukaemia cell lines, U937 and HL-60, were assessed alone or in combination with the retinoid compounds, 9-cis retinoic acid (9-cis RA) and all-trans retinoic acid (ATRA). The vitamin D derivatives acted to increase the differentiation of U937 and HL-60 cell cultures in a dose-dependent manner, as determined by nitroblue tetrazolium (NBT) reduction, with EB1089 and KH1060 being more effective than the native hormone. As an additional index of leukaemic cell differentiation, induction of expression of the phenotypic cell surface antigen, CD14, and the beta2-integrins, CD11b and CD18 by the vitamin D and retinoid compounds were monitored using fluorescence activated cell sorting (FACS) analyses. Following 96-hr treatment of U937 and HL-60 cells with 5 x 10(-10) M of the vitamin D derivatives, a striking increase in CD14 antigen expression was apparent, indicating the promotion by these compounds of a monocyte/macrophage lineage of cells. CD11b and CD18 antigen expression were also raised above control levels. In contrast, both retinoid compounds used at the higher concentration of 1 x 10(-8) M were not effective inducers of CD14 antigen expression. However, CD11b and CD18 were both readily increased in U937 and HL-60 cell cultures. Treatment of U937 cell cultures with the vitamin D compounds and the retinoids resulted in cooperative effects on induction of differentiation, with correlation by both NBT reduction and FACS analyses of CD14 antigen expression. The presence of 9-cis RA or ATRA appeared to contribute to the further increase of CD14 in these cells. HL-60 cell cotreatment with these compounds also displayed enhanced cooperative effects in phagocytic function by NBT reduction. However, analysis of CD14 revealed a dramatic diminution in HL-60 cells treated with the combinations of the vitamin D derivatives and the retinoids. Assessment of HL-60 cell morphology treated with these combinations demonstrated the presence of a mixed population of monocytes and granulocytes. CD11b and CD18 antigen expression was also enhanced in both cell lines with cotreatment. The ability of EB1089 and KH1060 to induce leukaemic cell differentiation may provide an additional option for therapeutic use alone or together with other differentiation agents such as 9-cis RA or ATRA.  相似文献   
996.
Oligodendrogliomas are uncommon intracranial glial tumours in which extracranial spread is only rarely reported. Similarly, both intracranial and ocular medulloepitheliomas are also rare, with metastatic spread from the ocular neoplasm being less common than its intracranial counterpart. We report cases of an intracranial oligodendroglioma and an ocular medulloepithelioma both of which metastasised to the parotid gland. To our knowledge these are only the second oligodendroglioma and the third ocular medulloepithelioma to be reported as metastasising to this site.  相似文献   
997.
998.
This paper develops a mitre model for the shear strain distribution in steel members under uniform torsion. The mitre model provides reasonable approximations for the shear stress distributions, except near re-entrant corners, and accurate predictions of the fully plastic uniform torque. The elastic torque-twist relationship is predicted with high accuracy, and the inelastic relationship with reasonable accuracy. The mitre model uses a simple approximation to the shear strain distribution caused by uniform torsion. It can be expected to provide a relatively simple method of predicting the inelastic behaviour of steel members when uniform torsion acts in combination with axial force and bending moment.  相似文献   
999.
It is pointed out that writers and editors have powerful formatting and typographical tools available in word processing and desktop publishing software that can be applied to headings to visually reveal or signal the structure of text, and thus the author's perspective. Results of studies are presented which suggest that (1) visual discriminations among headings are easier for a reader to make when headings vary on fewer rather than more formatting and typographical dimensions, (2) size is the most powerful visual cue to a heading's hierarchical position, (3) relative size differences among different levels of headings of about 20% are more discriminable than are absolute size differences, and (4) formatting cues are perceived by readers consistently but not necessarily conventionally  相似文献   
1000.
Insulin receptors differing structurally from those in other tissues have been demonstrated in brain from many species. Subtle differences in binding properties have been reported between insulin receptors in brain and other tissues, including differences in affinity of pig brain receptors for human and porcine insulin. Insulin binding has been demonstrated in human cerebral cortex, but insulin binding has not been characterized in other areas of human brain. We have studied the binding of 125I labelled human insulin, and its displacement by unlabelled human and porcine insulin, in homogenates prepared from human hypothalamus, cerebral cortex and cerebellum obtained post-mortem from eight non-diabetic subjects. Specific binding was demonstrated in all brain regions studied, and displacement curves obtained with unlabelled human and porcine insulin were identical. By contrast, unlabelled insulin-like growth factor-1 did not significantly displace 125I labelled human insulin over the same concentration range. We therefore conclude that insulin receptors are widely distributed in human brain and do not differ in their affinity for human and porcine insulin.  相似文献   
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