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141.
Sodium MRI of the human kidney at 3 Tesla.   总被引:6,自引:0,他引:6  
The sodium concentration gradient in the kidney (from the cortex to the medulla) serves to regulate fluid homeostasis and is tightly coupled to renal function. It was previously shown that renal function and pathophysiology can be characterized in rat kidneys by measuring the sodium gradient with (23)Na MRI. This study demonstrates for the first time the ability of (23)Na MRI to map the distribution of sodium in the human kidney and to quantify the corticomedullary sodium gradient. The study was performed on a 3T Signa LX scanner (GE) using an in-house-built quadrature surface coil. (23)Na images of volunteers were acquired using a 3D coronal gradient-echo sequence at a spatial resolution of 0.3 x 0.3 x 1.5 cm(3) in a 25-min scan time. The signal intensity (relative to the noise) increased linearly from the cortex to each of the medullae with a mean slope of 1.6 +/- 0.2 in relative arbitrary units per mm (Rel.u./mm, N = 6) and then decreased, as expected, toward the renal pelvis. Water deprivation (12 hr) induced a significant increase of 25% (P < 0.05) in this gradient. Based on these results, we suggest that sodium MRI can serve as a valuable noninvasive method for functional imaging of the human kidney.  相似文献   
142.
Krause I, Snir M, Cleper R, Fraser A, Kovalski Y, Axer Siegel R, Bar-Nathan N, Davidovits M. Ocular complications in children and adolescents following renal transplantation.
Pediatr Transplantation 2010: 14: 77–81. © 2009 Wiley Periodicals, Inc.
Abstract:  Ocular complications after renal transplantation are common in adults. Nevertheless, data regarding these complications in children are insufficient. The purpose of the present study was to assess ocular morbidity in pediatric renal graft recipients. A retrospective observational study of 71 patients aged 11.2 ± 5.5 yr was conducted. Mean duration of follow-up was 5.6 ± 3.5 yr. A total of 16 ocular complications were found in 12 (17%) of the patients. Three patients suffered from more than one complication. Cataract was the most common finding (six patients, 8.4%) followed by swollen disk and hypertensive retinopathy in four patients (5.7%) each and increased intra-ocular pressure in two patients (3%). Mean time interval between transplantation and occurrence of first abnormal ocular finding was 37 ± 34.5 months. The follow-up time was significantly longer in patients with ophthalmological problems than in those without complications (7.8 yr vs. 5.2 yr, p < 0.02). No statistically significant association was found between the occurrence of ocular complications and the age of the patients at transplantation, donor source, duration of dialysis prior to transplantation, previous corticosteroid therapy or presence of acute rejection episodes. The results of the study point to the importance of regular concurrent ophthalmological follow-up in pediatric renal graft recipients to reduce/prevent ocular morbidity.  相似文献   
143.
In response to physiological or psychological challenges, the brain activates behavioral and neuroendocrine systems linked to both metabolic and emotional outputs designed to adapt to the demand. However, dysregulation of integration of these physiological responses to challenge can have severe psychological and physiological consequences, and inappropriate regulation, disproportional intensity, or chronic or irreversible activation of the stress response is linked to the etiology and pathophysiology of mood and metabolic disorders. Using a transgenic mouse model and lentiviral approach, we demonstrate the involvement of the hypothalamic neuropeptide Urocortin-3, a specific ligand for the type-2 corticotropin-releasing factor receptor, in modulating septal and hypothalamic nuclei responsible for anxiety-like behaviors and metabolic functions, respectively. These results position Urocortin-3 as a neuromodulator linking stress-induced anxiety and energy homeostasis and pave the way toward better understanding of the mechanisms that mediate the reciprocal relationships between stress, mood and metabolic disorders.  相似文献   
144.
Objectives: To evaluate peak systolic velocity (PSV) in the umbilical artery (UA) among patients with single umbilical artery (SUA) as compared with patients with three vessel cords.

Methods: A prospective case-control study was performed. UA blood flow velocimetry was obtained from fetuses with SUA and from a control group with three vessel cord. PSV and pulsatility index (PI) were measured. Patients’ characteristics were compared for statistical differences and a linear regression model was constructed for the different groups.

Results: UA Doppler velocimetry measurements were obtained from 29 patients with SUA and from 29 controls matched for gestational age. The differences between UA PI with and without SUA were significant (F?=?3.471; p?=?0.0379) showing a lower PI in the SUA group. However, no significant statistical difference was found in PSV between these two groups (F?=?0.149; p?=?0.86).

Conclusions: While the impedance in the UA of patients with a SUA was lower compared with patients with a normal umbilical cord, the PSV did not differ.  相似文献   
145.
To understand the pattern of utilization of ambulatory care by parents of children with special health care needs (CSHCN) and to explore parental challenges in coping with health maintenance of their infants after discharge from a neonatal intensive care unit (NICU). CSHCN require frequent utilization of outpatient ambulatory clinics especially in their first years of life. Multiple barriers are faced by families in disadvantaged populations which might affect adherence to medical referrals. Our study attempts to go beyond quantitative assessment of adherence rates, and capture the influence of parental agency as a critical factor ensuring optimal utilization of healthcare for CSHCN. A prospective, mixed-methods, cohort study followed 158 Jewish and Bedouin-Arab infants in the first year post discharge from NICU in southern Israel. Rates of utilization of ambulatory clinics were obtained from medical records, and quantitative assessment of factors affecting it was based on structured interviews with parents at baseline. Qualitative analysis was based on home visits or telephone in-depth interviews conducted about 1 year post-discharge, to obtain a rich, multilayered, experiential perspectives and explained perceptions by parents. Adherence to post-discharge referrals was generally good, but environmental, cultural, and financial obstacles to healthcare, magnified by communication barriers, forced parents with limited resources to make difficult choices affecting utilization of healthcare services. Improving concordance between primary caregivers and health care providers is crucial, and further development of supportive healthcare for CSHCN in concordance with parental limitations and preferences is needed.  相似文献   
146.

Background

The social–ecological environment of undocumented children of migrant workers includes varying levels of risk factors. Growing up in these conditions compromises children’s development on all levels. Many of these children are in need of psychotherapy, however, due to limited resources, only a few of them receive mental health aid.

Objective

The present research undertook to construct and examine the effectiveness of a specialized group intervention program to enhance children’s self-efficacy and mental health.

Methods

Participants were 70 children aged 8–12 of illegal migrant workers in Israel. The repeated measures design included completion of a self-efficacy scale and emotional, behavioral and social difficulties child-report and teacher-report measures. Children were randomly allocated to either an intervention or control group.

Results

The first hypotheses predicting a greater improvement in self-efficacy between the pre-test and post-test for children in the intervention as opposed to control group was confirmed. The second hypothesis predicting a greater reduction in the self- and teacher-reports of emotional, social and behavioral difficulties was confirmed. The third hypothesis predicting a moderating relation between self-efficacy, group type and time on the dependent variables was confirmed only for children’s self-report of their difficulties.

Conclusions

Findings provide evidence for the effectiveness of this short term playful intervention program for this group of disadvantaged children, suggesting its application to other at-risk groups of children.  相似文献   
147.
Obesity, a chronic low-grade inflammatory condition is associated with the development of many comorbidities including dyslipidemia. This review examines interactions between single nucleotide polymorphisms (SNP) in the inflammatory genes tumor necrosis alpha (TNFA) and interleukin-6 (IL-6) and dietary fatty acids, and their relationship with obesity and serum lipid levels. In summary, dietary fatty acids, in particular saturated fatty acids and the omega-3 and omega-6 polyunsaturated fatty acids, impact the expression of the cytokine genes TNFA and IL-6, and alter TNFα and IL-6 production. In addition, sequence variants in these genes have also been shown to alter their gene expression and plasma levels, and are associated with obesity, measures of adiposity and serum lipid concentrations. When interactions between dietary fatty acids and TNFA and IL-6 SNPs on obesity and serum lipid were analyzed, both the quantity and quality of dietary fatty acids modulated the relationship between TNFA and IL-6 SNPs on obesity and serum lipid profiles, thereby impacting the association between phenotype and genotype. Researching these diet–gene interactions more extensively, and understanding the role of ethnicity as a confounder in these relationships, may contribute to a better understanding of the inter-individual variability in the obese phenotype.  相似文献   
148.

Correctional facilities now house unprecedented numbers of women with complex treatment needs. This investigation applied the Behavioral Model for Vulnerable Populations to study 168 jailed women with alcohol use disorders. It described the sample’s predisposing (age, race, victimization), enabling (health insurance), and need (self-reported medical, substance use, and mental health problems) factors and examined associations of these factors with pre-incarceration services utilization. Most participants had clinically significant levels of depression and PTSD symptoms, most took psychiatric medications, and most had been victimized. Participants reported considerable health services utilization. Younger, Black, and uninsured women utilized fewer medical and mental health services. Drug use was associated with less use of medical services, but more use of alcohol and drug services. High rates of health services use support the need for integrated, ongoing care for substance-using women before, during, and after incarceration.

  相似文献   
149.
Findings in previous studies investigating the beneficial effect of risperidone and olanzapine versus typical antipsychotics on quality of life (QOL) are controversial since they did not adjust for various factors contributing to QOL. To test this assumption in a naturalistic cross-sectional design, we evaluated general and domain-specific QOL scores for baseline data of schizophrenia outpatients stabilized on atypical (N = 78, risperidone or olanzapine) and typical (N = 55) agents. Self-report and observer-rated QOL outcomes of both risperidone and olanzapine with typical antipsychotic therapy were compared across demographic, illness-related, and treatment-related factors using analysis of variance, multivariate analysis of variance, and correlation analysis. No significant differences were found in QOL outcomes of risperidone-treated and olanzapine-treated patients. Both self-report and rater-observed QOL measures indicated superiority of atypical over typical antipsychotic agents after adjusting for daily doses, duration of treatment, subjective tolerability, and adjuvant antidepressants. Lower daily doses and longer antipsychotic treatment were associated with better QOL. Self-report and observer-rated QOL scores correlated positively (r = 0.64, P < 0.001). Gender, marital status, age, education, living arrangement and employment status, age of onset, illness duration, symptom severity, emotional distress, subtypes of schizophrenia, and side effects did not affect QOL outcomes in either group. Risperidone and olanzapine revealed an advantage over typical agents in terms of QOL. Findings suggest that when calculating the beneficial effects of atypical antipsychotic therapy on QOL outcomes, daily doses, duration of treatment, and subjective tolerability may be intervening variables and should be adjusted accordingly to clearly appreciate benefits of atypical antipsychotics.  相似文献   
150.
Attachment is a behavioral and physiological system, which enables individual’s dynamic adaptation to its environment. Attachment develops in close interaction between an infant and his/her mother, plays an important role in the development of the infant’s brain, and influences the quality of interpersonal relationships throughout life.Security of attachment is believed to influence individual response to stress, exposing insecurely organized individuals to deregulated autonomic nervous system and exaggerated hypothalamic-pituitary-adrenal activity, which, in turn, produces increased and prolonged exposure to stress-hormones. Such stress responses may have considerable implications for the development of diverse health-risk conditions, such as insulin resistance and hyperlipidemia, shown by numerous studies.Although the mechanisms are not yet fully understood, there is compelling evidence highlighting the role of psychological stress in the development of type 1 diabetes (T1D). One of the possible contributing factors for the development of T1D may be the influence of attachment security on individual stress reactivity. Thus, the suggestion is that insecurely attached individuals are more prone to experience increased and prolonged influence of stress hormones and other mechanisms causing pancreatic beta-cell destruction.The present paper opens with a short overview of the field of attachment in children, the principal attachment classifications and their historic development, describes the influence of attachment security on individual stress-reactivity and the role of the latter in the development of T1D. Following is a review of recent literature on the attachment in patients with T1D with a conclusion of a proposed role of attachment organization in the etiology of T1D.  相似文献   
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