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11.
Thirty-seven patients with major affective disorders according to DSM-III and on continuous lithium treatment were followed during a 7-year period. Outcome was assessed by use of the Comprehensive Psychopathological Rating Scale and by the need for additional psychotropic medication and for hospital and outpatient care. Anamnestic variables and patient's attitudes to their lithium medication were also included in the analysis of outcome, as were laboratory data, including lithium parameters. An increase in psychopathology was demonstrated in a significant number of patients and was attributed mainly to an increase in the depressive symptoms, with a significant increase in the rated scores for fatiguability, pessimistic thoughts, reduced sleep, and inner tension. Suicidal thoughts were common, but no suicide attempts were made. A significant number of patients complained of failing memory, but no significant progression was demonstrated during the 7-year study period. The increase in the depressive symptoms was closely correlated with the number of hospital admissions for depressive recurrence and with the number of days in hospital. The following factors showed a significant relationship with the increase in depressive symptoms: serum lithium levels, large increase in the elimination half-life of lithium, low level of social functioning, low TSH values, and need of concomitant administration of antidepressants and benzodiazepines.  相似文献   
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The parents of 14 individuals with severe/profound mental disabilities were interviewed one and three years after their children graduated or aged out of high school. Two categories of information were sought concerning the adult adjustment of these individuals. General status variables included marital status, place of residence, agencies contacted concerning employment opportunities, financial resources, leisure activities, means of transportation, sources of help in resolving problems, and amount of postsecondary training. Employment variables included location of employment, wages, number of hours worked per week, and job benefits received. Results indicated that three years after exiting high school, all participants were very dependent upon others for housing, transportation, and financial assistance. Ten of the 14 individuals were employed 3 years after exiting high school, all in sheltered workshops.  相似文献   
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Summary Vestibulocollic (VCR) and vestibulo-ocular (VOR) reflexes were studied during angular rotation in the horizontal plane in precollicular decerebrate cats. Angular position was modulated by sinusoids or sums of sinusoids with frequencies ranging from 0.05 to 5 Hz.Reflex motor output was measured by recording electromyographic (EMG) activity of the lateral rectus and dorsal neck muscles and discharge of abducens motoneurons. Measured with respect to input angular acceleration VCR motor output displayed a second order lag at low frequencies, bringing mean EMG phase (–136 °) and gain slope (–35 dB/ decade) close to those of an angular position signal at 0.2 Hz. At higher frequencies the lag was counteracted by a second order lead bringing mean phase (–52 °) and gain slope (–5.6 dB/decade) back close to those of an angular acceleration signal at 3 Hz. By contrast, mean phase (–113 ° to –105 °) and gain slope (–21 to –28 dB/decade) of the VOR motor output remained close to those of an angular velocity signal across the entire frequency range.The data suggest that neural pathways producing the VCR receive selective input from irregular type horizontal semicircular canal afferents which provide one lag and one lead in the overall transfer function while the other lag and lead are produced by central pathways.Transaction of the medial longitudinal fasciculus (MLF), which eliminates all of the most direct (three neuron) arcs of the horizontal VCR, did not cause any detectable change in the horizontal VCR at either low or high frequencies. Reductions in overall gain occurred in some cases but these could be attributed to damage to axons outside the MLF. Less direct pathways, probably including vestibulo-reticulospinal pathways, are thus able to produce both the low-frequency, phase-lagging and high-frequency, phase-leading components of the horizontal VCR.Supported in part by NIH grants EY 02249, EY 00100, and NS 02619Recipient of NIH Fellowship NS 06030  相似文献   
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This study investigated the contribution of genetic and environmental influences on the stability of aggressive behavior from early childhood to adolescence. Two developmental models, the simplex model and the common factor model, were tested to study the underlying processes of stability and change. Measures of aggressive behavior (AGG) were obtained from maternal CBCL data as part of a large ongoing longitudinal study of the Netherlands Twin Registers (NTR) and included data from 6488 three-year-old twin pairs, 5475 seven-year-old twin pairs, 2983 ten-year-old twin pairs, and 1509 twelve-year-old twin pairs. AGG showed moderate to high stability during childhood. The stability coefficients ranged from 0.41 to 0.77 across varying intervals. Averaged across boys and girls, genetic factors accounted for approximately 65% of the total stability. Longitudinal genetic analysis indicated a simplex model for genetic effects, which suggests a dynamic development process consisting of transmission of existing genetic effects interacting with new genetic influences. This is especially true at age 7, when the influence of new genetic factors was large. Shared environmental factors accounted for approximately 25% of phenotypic stability, and it seemed that a stable set of the same shared environmental factors underlay the development of AGG. Nonshared environmental factors, when important, are age specific. Sex-specific differences for stability were identified. For boys, genetic influences were greater, whereas for girls shared environmental factors were more important. These data support the idea that both genetic and environmental influences play a role in the stability of AGG from age 3 to 12.  相似文献   
15.
The affinity of anti-gag antibody was studied for up to 9 years (1984-1993) in sera from 15 HIV-1+ patients with haemophilia. On the basis of their 1993 clinical status patients were divided into two groups: (i) patients who remained asymptomatic (n = 9); and (ii) those who progressed to AIDS between late 1987 and 1993. The affinity constants of antibody for p24 and p17 were determined by a double isotope fluid-phase radioimmunoassay; and the relationships between antibody affinity and titre, patient clinical course, CD4 cell counts and p24 antigenaemia were analysed. The affinity of p24- and p17-specific antibody was up to 100 times greater in asymptomatic patients than in patients who progressed to AIDS. Patients who developed AIDS either lost or failed to develop high-affinity antibodies early in the infection. Asymptomatic patients maintained high-affinity antibodies for several years; however, in some of these patients the affinity of anti-p24 and p17 antibodies subsequently fell later in the study period. The presence of low-affinity antibody and progressive reduction in the titre of specific antibody were earlier predictors of disease onset than CD4 cell counts. The failure to either develop or maintain high affinity gag-specific antibody suggests an early impairment of T helper function in individuals who progressed to AIDS. The presence of antibody of high affinity could be essential in controlling virus replication and the onset of AIDS.  相似文献   
16.
Scope: B vitamers are co-enzymes involved in key physiological processes including energy production, one-carbon, and macronutrient metabolism. Studies profiling B vitamers simultaneously in parent–child dyads are scarce. Profiling B vitamers in parent–child dyads enables an insightful determination of gene–environment contributions to their circulating concentrations. We aimed to characterise: (a) parent–child dyad concordance, (b) generation (children versus adults), (c) age (within the adult subgroup (age range 28–71 years)) and (d) sex differences in plasma B vitamer concentrations in the CheckPoint study of Australian children. Methods and Results: 1166 children (11 ± 0.5 years, 51% female) and 1324 parents (44 ± 5.1 years, 87% female) took part in a biomedical assessment of a population-derived longitudinal cohort study: The Growing Up in Australia’s Child Health CheckPoint. B vitamer levels were quantified by UHPLC/MS-MS. B vitamer levels were weakly concordant between parent–child pairs (10–31% of variability explained). All B vitamer concentrations exhibited generation-specificity, except for flavin mononucleotide (FMN). The levels of thiamine, pantothenic acid, and 4-pyridoxic acid were higher in male children, and those of pantothenic acid were higher in male adults compared to their female counterparts. Conclusion: Family, age, and sex contribute to variations in the concentrations of plasma B vitamers in Australian children and adults.  相似文献   
17.
The COVID-19 pandemic has had a significant impact on populations at an economic, health, and on an interpersonal level, it is still unclear how it has affected health-risk behaviors, such as comfort food consumption over time. This study longitudinally examines the effect of the perceived impact of COVID-19 on comfort food consumption and whether this effect is mediated by emotional distress. A convenience sample of 1048 students and university staff (academic and non-academic) from two universities completed monthly online surveys during the COVID-19 pandemic across six waves (W; W1 to W6). Participants reported their perceived impact of COVID-19 (economic, interpersonal, and health), comfort food consumption, and emotional distress (DASS-21). Using structural equation models, we found an indirect longitudinal effect of the perceived impact of COVID-19 (W1) on comfort food consumption (W3 to W6) through increased emotional distress (W2). The perceived negative impact of COVID-19 on comfort food consumption was fully mediated by the emotional distress during the first waves (W3 and W4), ending in a partial mediation in the last waves (W5 and W6). These findings contribute to disentangling the mechanisms by which the perceived impact of COVID-19 affects comfort food consumption over time, and highlight the role of emotional distress. Future interventions should address comfort food consumption by focusing on handling emotional distress during a crisis.  相似文献   
18.
本文针对学生在学习核磁共振的过程中 ,在理解纵向弛豫时间T1和横向弛豫时间T2 时经常提出的疑问 ,建构两个物理模型 ,以便于学生能深刻理解T1、T2 的物理学 ,生物学意义 ,为读释图像 ,挖掘生物信息奠定更牢固的理论基础。  相似文献   
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