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1.
Protein-calorie malnutrition (PCM) adversely affects more or less all immune competent cells. Nonspecific immunity is impaired, particularly adherence and chemotaxis of phagocytes, although the responsiveness of circulating cells may not be the same as that of noncirculating cells. PCM results in numerical and functional impairment in lymphocytes. PCM markedly affects IgG class antibodies which have the highest affinity when directed against T-dependent antigens. These impairments are interrelated, since cooperation between T-helper cell and B-cells is depressed, and the antigen presentation to T-helper cells by macrophages is deficient.  相似文献   
2.
The prevalence of cardiovascular disease (by EKG criteria) in patients with rhegmatogenous retinal detachments has been reported to be more than four times that found in age-matched controls. Adhesion between the retinal pigment epithelium (RPE) and the photoreceptors is facilitated by RPE transport. Because RPE transport is driven by a Na-K ATPase, it has been suggested that the correlation of EKG abnormalities and retinal detachment may be due to clinical use of digoxin, a Na-K ATPase inhibitor frequently given to patients with cardiovascular disease. The prevalence of EKG abnormalities in 299 consecutive patients with primary retinal detachment is about the same as that reported previously. However, 92% of these patients with EKG abnormalities did not take digoxin. Therefore, clinical use of digoxin cannot account for the reported association of EKG abnormalities and rhegmatogenous retinal detachment.  相似文献   
3.
Summary An aberrant crossed corticotectal pathway can be generated by removal of one visual cortex and the contralateral superior colliculus from newborn rats. This aberrant crossed corticotectal projection arises from the pyramidal neurons located in layer V of the visual cortex and terminates in a spatially orderly manner in the appropriate laminae of the cortically deafferented contralateral colliculus. Comparable results cannot be reproduced by unilateral collicular lesions alone. The significance of these findings and the possible mechanisms involved in the formation of the aberrant pathway are discussed and compared with the retinotectal system.The research was supported by USPHS Grant EY-00596 from the National Institutes of Health  相似文献   
4.
This study explores marital processes that may underlie the apparent decline in satisfaction with marriage in partners becoming parents for the 1st time. The study assessed 47 couples expecting a 1st child and 15 couples not yet decided about having a child at pretest, post 1 (6 months post partum of 9 months after pretest) and post 2 (18 months postpartum or 21 months after pretest). Questionnaires examined: 1) psychological sense of self; 2) partners' role arrangements and communication; 3) parenting ideology; 4) perceptions of the family of origin; and 5) social support and life stress, including parents' work patterns. Parenthood seems to bring more change, and more negative change, in each of the 5 domains of family life that were investigated for comparable couples not having a 1st child experience over a similar period of time. Quantitative data support this conclusion in 4 of the 5 domains (individuals sense of self, marital, parent-child, and outside the family). Interview data suggest that new parents' relationships with their families of origin also undergo change at this time. Although shifts within domains often showed patterns similar to change in overall satisfaction with the marriage, the connection between the 2 was not linear and direct, especially for women. Men and women in transition to parenthood become increasingly different from one another; the results suggest that increased gender differentiation accompanying the transition to parenthood is a factor in accounting for marital satisfaction decline.  相似文献   
5.
Global versus local processing: Is there a hemispheric dichotomy?   总被引:1,自引:0,他引:1  
D B Boles 《Neuropsychologia》1984,22(4):445-455
A major dichotomy proposed for lateralized information processing is that the right and left cerebral hemispheres are "global" and "analytic" processors respectively. Here three experiments employed a tachistoscopic recognition paradigm with letter patterns varying in size and composition. No visual field asymmetries in RT were found in the first two experiments, although statistical power was high and a Stroop-like effect ("global precedence") was supported. Experiment 3 resulted in a right field advantage for vocal naming responses yet no asymmetry for manual responses, suggesting that both hemispheres can recognize global and local patterns, but that introduction of a laterally controlled response independently determines asymmetry.  相似文献   
6.
7.
The evaluation of telemedicine activity in rural communities is complicated by the fact that most telemedicine sites are chosen because of their existing telecommunications infrastructure and institutional relationships, not by a random selection process. In addition, it is difficult to draw conclusions about the effects of telemedicine without a careful analysis of parallel changes in communities which do not have access to telemedicine services. We have developed a method of identifying comparable counties based on an aggregate measure of health status. A set of 66 variables was collected in a previous project to develop a model to evaluate the relative health status of the population in Missouri. A stepwise regression was used to identify a subset of 15 variables that had the highest predictive value for the health status of a county. Distance measures were then used to identify six counties which were most similar to three telemedicine counties. The method can be used with any study set chosen non-randomly, to identify similar objects that can be used for comparative purposes.  相似文献   
8.
OBJECTIVE: Whether chronicity of illness produces progressive neural abnormality is an important question in current schizophrenia research. Positron emission tomography (PET) offers an opportunity to visualize and measure blood flow in vivo to address this issue. The authors previously compared healthy volunteers with neuroleptic-naive patients experiencing their first episode of schizophrenia and reported that abnormalities in blood flow, including lower flow in prefrontal regions and higher flow in the thalamus and cerebellum, are present at the early stage of schizophrenic illness. The goal of the present study was to measure blood flow with PET in patients with chronic schizophrenia. METHOD: PET was used to examine regional cerebral blood flow (rCBF) in 30 patients with chronic schizophrenia and 30 normal comparison subjects. To determine if the patterns of flow abnormality in the patients with chronic schizophrenia were similar to those of patients experiencing their first episode of schizophrenia, the same cognitive condition was examined as in the earlier study. The patients with chronic schizophrenia in the current study had been neuroleptic-free for at least 3 weeks. RESULTS: As in the authors' previous study, the chronically ill patients showed lower flow in prefrontal areas and higher flow in thalamic and cerebellar regions than normal comparison subjects, suggesting that a similar neural dysfunction occurs in both first-episode and chronic schizophrenia. CONCLUSIONS: rCBF abnormalities in patients with chronic schizophrenia are not due to chronicity of illness or the effects of medication. These results provide evidence that the primary neural abnormalities in schizophrenia may occur in cortical, cerebellar, and thalamic regions and that the dysfunction in these regions may explain the "loosening of associations" that Bleuler considered to be the fundamental cognitive phenotype of schizophrenia. These abnormalities can be reconceptualized as "cognitive dysmetria."  相似文献   
9.
This pilot study examined the relationship between substance dependence and violence in a sample of severely mentally ill adults. Subjects were 42 psychiatric outpatients enrolled in a clinical case management program in San Francisco, California. Almost 40% of the participants reported perpetrating at least one violent act in the past 12 months. Comorbid participants were over 4% times more likely to commit a violent act in the past 12 months than noncomorbid participants. Substance dependence was also more frequently associated with perpetration of a violent act by female than by male participants and by Caucasian than by African American participants. Comorbid mentally ill participants appear more likely to perpetrate violent acts than those with mental illness alone. The dangers of substance dependence in terms of the perpetration of violence may not be in mental illness or substance dependence alone but in their co‐occurrence. Further investigation is needed to assess risk factors for violence and victimization in multiple environmental and situational domains. It will be important to explore the moderating effects of gender and race on the co‐occurrence of mental illness, substance dependence, and the perpetration of violent acts.  相似文献   
10.
Short sleep duration has increased in tandem with rising obesity levels in all age groups. Research on parent mental health and its relationship with childhood obesity has been growing in recent years. This cross-sectional study assessed children’s zBMI (Body Mass Index adjusted for age and sex) and parent-reported children’s sleep behaviors, parents’ negative emotional state, and parents’ marital status in a sample of 4- to 5-year-old children. Eight-hundred seventy-seven parents answered the DASS (Depression Anxiety Stress Scales) and CSHQ (Children’s Sleep Habit Questionnaire) and reported children’s height and weight. Children in the ≥ 85th percentile weight category had significantly more sleep behavior problems than children in the < 85th percentile weight category. Mothers of children in the ≥ 85th percentile weight category were more likely to be in the overweight/obese category and had more depressive symptoms than mothers of children in the < 85th percentile weight category. Single fathers had higher levels of anxiety and depression and their children had greater sleep behavior problems than fathers in a relationship/married. The findings indicate a difference between children below and above the 85th BMI percentile in terms of children’s sleep habits and parents’ negative emotional state.  相似文献   
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