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1.

Background  

Knowledge of the structure and character of inter-organizational relationships found among health promotion organizations is a prerequisite for the development of evidence-based network-level intervention activities. The Alberta Healthy Living Network (AHLN) mapped the inter-organizational structure of its members to examine the effects of the network environment on organizational-level perceptions. This exploratory analysis examines whether network structure, specifically partnership ties among AHLN members, influences organizational perceptions of support after controlling for organizational-level attributes.  相似文献   
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A cross-sectional survey and subsequent longitudinal study among diabetic residents of Rochester, MN--The Rochester Diabetic Neuropathy Study (RDNS)--is population-based and uses quantitative, validated, and unique end points to detect, classify, and stage neuropathy. Nondiabetic persons, drawn from the same population, serve as controls. For patients 10 to 70 years old, the RDNS cohort is representative of diabetics living in Rochester, MN. We assessed reproducibility of tests used to characterize and quantitate severity of neuropathy in 20 diabetic subjects without neuropathy and with varying severities of neuropathy. Using intraclass correlation coefficient (rI) as a measure of test reproducibility, we found high rI (usually 0.9 or better) with small confidence intervals for the Neurologic Disability Score (NDS); weakness subset of NDS (W-NDS); vibratory and cooling detection thresholds (using computer-assisted sensory examination [CASE] IV); compound muscle action potentials; sensory nerve action potentials; and motor nerve conduction velocities. There was good agreement among three trained observers for NDS and the W-NDS.  相似文献   
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Two soluble invariant chain (Ii) peptides with overlapping sequences had contrasting effects on the presentation of antigenic peptides by murine Ad, Ak, Ed, and Ek major histocompatibility complex (MHC) class II molecules. Naturally produced class II-associated invariant chain peptides human (h)Ii81–104/murine (m)Ii80–103 inhibited antigen presentation on these MHC class II alleles in a manner consistent with competitive inhibition. The Ii-4 peptides hIi77–92/mIi76–91 enhanced presentation of antigenic peptides on I-E class II alleles by promoting the exchange of peptides at the cell surface. Treatment of antigenpresenting cells (APC) with Ii-4 before the addition of antigenic peptide greatly enhanced subsequent T cell responses, while treatment of APC with Ii–4 after antigenic peptide binding decreased subsequent T cell responses. The hIi81–104 and mIi80–103 peptides inhibited T cell responses in both types of assays. The binding of biotinylated antigenic peptide to MHC class II-transfected L cells, as measured by flow cytometry, was inhibited by mIi80-103 and enhanced by mIi-4. Segments of Ii fragments remaining associated with MHC class II, or released Ii peptides, appear to regulate the formation of stable antigenic peptide/MHC class II complexes either positively or negatively through interactions at or near the antigenic peptide binding site. These findings open a pathway for the design of novel therapeutics based on the structure and function of natural and rationally designed fragments of Ii.  相似文献   
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The mothers and fathers of 11 preschool autistic children were taught operant procedures used in teaching speech to nonverbal children. The children's speech skills were assessed twice before and once after their parents were trained. At posttreatment, the children showed significant gains in prespeech and speech skills as measured by a 21-step hierarchy of speech behaviors. Those children who had acquired at least verbal imitative skill after training made greater progress than those who had not. Although children maintained their gains in a 1-year follow-up assessment, there was no evidence of significant improvement beyond that achieved at the end of training. The importance of support for parents in continuing to do formal teaching after the training program ends was stressed.Support for this research came in part from a grant from the National Institute of Mental Health (MH 29897-04) to the first author. Our thanks to Elayne Weitz, who co-led one of the groups, to Beverly Brysk for data processing, and to Rona Milch for statistical consultation.  相似文献   
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Introduction: Scarring and non-scarring alopecias have rarely been described to occur together in the same patient. Distinguishing these two different types of alopecia is important as treatment and prognosis can be different.Case presentation: Here, we report the first case of simultaneous alopecia areata (AA) and central centrifugal cicatricial alopecia (CCCA) in a 35-year-old woman. New alopecic patches were noted on her frontal and vertex scalp. Biopsy of the frontal scalp revealed miniaturi...  相似文献   
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This study explores the interaction between working memory systems and language processing by examining how differences in working memory capacity (WMC) modulates neural activation levels and functional connectivity during sentence comprehension. The results indicate that two working memory systems may be involved in sentence comprehension, the verbal working memory system and the episodic buffer, but during different phases of the task. A sub-region of the left inferior frontal gyrus (BA 45) was correlated with WMC during the probe and not during sentence reading while the only region to reveal a correlation with WMC during sentence reading was the posterior cingulate/precuneus area, a region linked to event representation. In addition, functional connectivity analysis suggests that there were two distinct networks affected by WMC. The first was a semantic network that included the middle temporal cortex, an anterior region of the inferior frontal gyrus and the inferior parietal region. The second included the posterior cingulate and BA 45 of the inferior frontal gyrus. We propose here that high capacity readers may generate an event representation of the sentence during reading that aids in comprehension and that this event representation involves the processing of the posterior cingulate cortex.  相似文献   
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