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In this case study, we describe a method that has potential to provide systematic support for public health information management. Public health agencies depend on specialized information that travels throughout an organization via communication networks among employees. Interactions that occur within these networks are poorly understood and are generally unmanaged. We applied organizational network analysis, a method for studying communication networks, to assess the method's utility to support decision making for public health managers, and to determine what links existed between information use and agency processes. Data on communication links among a health department's staff was obtained via survey with a 93% response rate, and analyzed using Organizational Risk Analyzer (ORA) software. The findings described the structure of information flow in the department's communication networks. The analysis succeeded in providing insights into organizational processes which informed public health managers' strategies to address problems and to take advantage of network strengths.  相似文献   
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Influence of nanoporous alumina membranes on long-term osteoblast response   总被引:8,自引:0,他引:8  
A major goal of bone tissue engineering is to design better scaffold configuration and materials to better control osteoblast behavior. Nanoporous architecture has been shown to significantly affect cellular response. In this work, nanoporous alumina membranes were fabricated by a two-step anodization method to investigate bone cell response. Osteoblasts were seeded on nanoporous alumina membranes to investigate both short-term adhesion and proliferation and long-term functionality and matrix production. Cell adhesion and proliferation were characterized using a standard MTT assay and cell counting. The total protein content was measured after cell lysis using the BCA assay. Matrix production was characterized in terms of surface concentrations of calcium and phosphorous, components of bone matrix, using X-ray photoelectron spectroscopy (XPS). The results from nanoporous alumina membranes were compared with those of amorphous alumina, aluminum, commercially available ANOPORE and glass. Results indicate improved osteoblast adhesion and proliferation and increased matrix production after 4 weeks of study.  相似文献   
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Laparoscopic cholecystectomy is usually a low‐risk procedure associated with a short stay and a low rate of conversion to open surgery. Complications are sometimes associated with anomalous vascular or biliary anatomy. Outlined below are the variations in vascular and biliary anatomy which may result in complications either due to involvement in the inflammatory process or inadvertent division during dissection. Clin. Anat. 30:1103–1106, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
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In hamsters (Mesocricetus auratus), anabolic-androgenic steroid (AAS) exposure during adolescence facilitates offensive aggression that is modulated, in part, by serotonin (5-HT) signaling and development and by signaling and expression of 5-HT1B receptors. To examine whether these effects are persistent or reversible, the authors administered AAS to hamsters, then examined them for aggression at 1, 4, 11, 18, or 25 days following cessation of AAS treatment. Then, 1 day later, hamsters were killed by transcardial perfusion and examined for 5-HT afferents to and 5-HT1B receptor-containing neuronal puncta and somata in areas of the brain altered by AAS, namely, the anterior hypothalamus, ventrolateral hypothalamus, and medial amygdala. Although aggression resulting from AAS exposure returned to control, nonaggressive levels by 18 days following cessation of AAS treatment, alterations in 5-HT afferent innervation and 5-HT1B receptor localization were observed throughout the extended time period examined. These data suggest that adolescent AAS exposure may have long-term, irreversible effects on 5-HT neural systems and that return to nonaggressive behavioral phenotypes following adolescent AAS exposure may not be a function of plasticity in central 5-HT systems.  相似文献   
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SARS-CoV-2 NSP12, the viral RNA-dependent RNA polymerase (RdRp), is required for viral replication and is a therapeutic target to treat COVID-19. To facilitate research on SARS-CoV-2 NSP12 protein, we developed a rat monoclonal antibody (CM12.1) against the NSP12 N-terminus that can facilitate functional studies. Immunoblotting and immunofluorescence assay (IFA) confirmed the specific detection of NSP12 protein by this antibody for cells overexpressing the protein. Although NSP12 is generated from the ORF1ab polyprotein, IFA of human autopsy COVID-19 lung samples revealed NSP12 expression in only a small fraction of lung cells including goblet, club-like, vascular endothelial cells, and a range of immune cells, despite wide-spread tissue expression of spike protein antigen. Similar studies using in vitro infection also generated scant protein detection in cells with established virus replication. These results suggest that NSP12 may have diminished steady-state expression or extensive posttranslation modifications that limit antibody reactivity during SARS-CoV-2 replication.  相似文献   
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Drug abuse researchers have noted striking similarities between behaviors elicited by Pavlovian sign-tracking procedures and prominent symptoms of drug abuse. In Pavlovian sign-tracking procedures, repeated paired presentations of a small object (conditioned stimulus, CS) with a reward (unconditioned stimulus, US) elicits a conditioned response (CR) that typically consists of approaching the CS, contacting the CS, and expressing consummatory responses at the CS. Sign-tracking CR performance is poorly controlled and exhibits spontaneous recovery and long-term retention, effects that resemble relapse. Sign-tracking resembles psychomotor activation, a syndrome of behavioral responses evoked by addictive drugs, and the effects of sign-tracking on corticosterone levels and activation of dopamine pathways resemble the neurobiological effects of abused drugs. Finally, the neurobiological profile of individuals susceptible to sign-tracking resembles the pathophysiological profile of vulnerability to drug abuse, and vulnerability to sign-tracking predicts vulnerability to impulsive responding and alcohol self-administration. Implications of sign-tracking for models of drug addiction are considered.  相似文献   
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