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41.
Measures of heart rate and forehead temperature on 238, 21-month-old children exposed to mild laboratory stressors revealed 2 provocative results. More children were cooler on the left side of the forehead than on the right side of the forehead, and those with a cooler left side of the forehead had lower heart rates. These data suggest that some aspects of cerebral asymmetry and cardiovascular reactivity may be mediated by a common set of processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
The 6 resolutions adopted by the Conference on Education in Professional Psychology were concerned with standards in the education of professional psychologists. Some of the issues addressed included the need for an increase in the number of professional psychologists, the assessment and prediction of professional competence, and the curricula of practitioner-model programs in professional psychology. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
In contrast to sessile cell types, lymphocytes migrate through the vasculature to become diffusely distributed in tissues or organized in lymphoid structures. A complex array of adhesion molecules including selectins, integrins and their counter-receptors mediate lymphocyte homing and migration into tissues and may be constitutively expressed or induced. However, the molecules that mediate the tissue-specific retention of lymphocytes within the parenchyma have not been identified. Along the epithelium at the basolateral surface of enterocytes, intestinal intraepithelial lymphocytes are found. These T cells of the mucosal immune system serve as a model for the tissue-specific compartmentalization of lymphocytes. We investigated whether the localization of these intestinal intraepithelial lymphocytes could be mediated by specific interactions between adhesion molecules expressed selectively on this subpopulation of T cells and tissue-restricted adhesion molecules on epithelial cells. Here we show that heterotypic adhesive interactions between epithelial cells and intraepithelial lymphocytes in vitro are mediated by E-cadherin and the alpha E beta 7 integrin.  相似文献   
44.
To examine the associations between intakes of calcium, Vitamin D, and dairy foods and the risk of colon cancer, the authors analyzed data from a prospective study of 47,935 US male professionals, 40-75 years of age and free of cancer in 1986. Within this cohort, 203 new cases of colon cancer were documented between 1986 and 1992. After adjusting for age and total energy intake, the authors found that the intake of calcium from foods and supplements was inversely associated with colon cancer risk (relative risk (RR) = 0.58, 95% confidence interval (CI) 0.39-087 between high and low intakes of calcium). However, after adjusting for confounding variables, they found that the trend was no longer statistically significant (p = 0.22), and the relative risk for the highest quintile group of intake was attenuated: 0.75 (95% CI 0.48-1.15). Similar results were observed for total vitamin D intake; the age- and energy-adjusted relative risk was 0.54% (95% CI 0/34-0/85) for the highest versus lowest quintile group, and this was attenuated in the multivariate model (RR = 0.66, 95% CI 0.42-1.05). The inverse association was weaker for dietary vitamin D (RR highest vs. lowest quintile = 0.88. 95% CI 0.54-1.42) and strongest for vitamin D arising from vitamin supplements (RR = 0.48, 95% CI 0.22-1.02). Thus, it is possible that other components of multivitamin use rather than vitamin D accounted for the reduction in risk. Consumption of milk and fermented dairy products was not significantly associated with the risk of colon cancer; individuals consuming two or more glasses of "whole" or skim milk per day had a relative risk of 1.09 (95% CI 0.69-1.72), compared with those who consumed "whole or skim milk less than once a month. These prospective data do not support the hypothesis that calcium intake is strongly protective against colon cancer risk, although a modest association cannot be excluded.  相似文献   
45.
We have analysed the replication of the heterochromatic megachromosome that was formed de novo by a large-scale amplification process initiated in the centromeric region of mouse chromosome 7. The megachromosome is organized into amplicons approximately 30 Mb in size, and each amplicon consists of two large inverted repeats delimited by a primary replication initiation site. Our results suggest that these segments represent a higher order replication unit (megareplicon) of the centromeric region of mouse chromosomes. Analysis of the replication of the megareplicons indicates that the pericentric heterochromatin and the centromere of mouse chromosomes begin to replicate early, and that their replication continues through approximately three-quarters of the S-phase. We suggest that a replication-directed mechanism may account for the initiation of large-scale amplification in the centromeric regions of mouse chromosomes, and may also explain the formation of new, stable chromosome segments and chromosomes.  相似文献   
46.
PROBLEM: Recurrent spontaneous abortion occurs in 1 in 500 random matings and usually results in abortion of all pregnancies. If absence of antibody to a paternally derived antigen caused abortion, the woman would be expected to make antibody to the other paternal antigen and abort only half her pregnancies. METHODS: Microvesicles were prepared from equine placentae. Acid-eluted IgG antibody was eluted from the polymorphic R80K antigen and used to type the residual R80K antigen on vesicles or on peripheral blood leucocytes. RESULTS: In several equine sibships all the half-sibs had the same paternal R80K alloantigen. In the extended horse family descended from the stallion Nearco, three allotypes were found. The allele present was usually the grandpaternal one, but exceptions are seen. Whichever allele is transmitted all the progeny have the same alloantigen (probability of this occurring by chance = 2(-45)). CONCLUSION: Because only one paternal allotype is present in all progeny, lack of antibody to the R80K antigen would result in loss of all pregnancies, not one half.  相似文献   
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