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41.
A growing number of investigators have commented on the lack of models to inform the design of behavioral intervention technologies (BITs). BITs, which include a subset of mHealth and eHealth interventions, employ a broad range of technologies, such as mobile phones, the Web, and sensors, to support users in changing behaviors and cognitions related to health, mental health, and wellness. We propose a model that conceptually defines BITs, from the clinical aim to the technological delivery framework. The BIT model defines both the conceptual and technological architecture of a BIT. Conceptually, a BIT model should answer the questions why, what, how (conceptual and technical), and when. While BITs generally have a larger treatment goal, such goals generally consist of smaller intervention aims (the "why") such as promotion or reduction of specific behaviors, and behavior change strategies (the conceptual "how"), such as education, goal setting, and monitoring. Behavior change strategies are instantiated with specific intervention components or “elements” (the "what"). The characteristics of intervention elements may be further defined or modified (the technical "how") to meet the needs, capabilities, and preferences of a user. Finally, many BITs require specification of a workflow that defines when an intervention component will be delivered. The BIT model includes a technological framework (BIT-Tech) that can integrate and implement the intervention elements, characteristics, and workflow to deliver the entire BIT to users over time. This implementation may be either predefined or include adaptive systems that can tailor the intervention based on data from the user and the user’s environment. The BIT model provides a step towards formalizing the translation of developer aims into intervention components, larger treatments, and methods of delivery in a manner that supports research and communication between investigators on how to design, develop, and deploy BITs.  相似文献   
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This paper presents the synthesis, characterization, and multiscale modeling of hybrid composites with enhanced interfacial properties consisting of aligned zinc oxide (ZnO) nanowires and continuous carbon fibers. The atomic layer deposition method was employed to uniformly synthesize nanoscale ZnO seeds on carbon fibers. Vertically aligned ZnO nanowires were grown from the deposited nanoscale seeds using the low-temperature hydrothermal method. Morphology and chemical compositions of ZnO nanowires were characterized to evaluate the quality of synthesized ZnO nanowires in hybrid fiber-reinforced composites. Single fiber fragmentation tests reveal that the interfacial shear strength (IFSS) in epoxy composites improved by 286%. Additionally, a multiscale modeling framework was developed to investigate the IFSS of hybrid composites with radially aligned ZnO nanowires. The cohesive zone model (CZM) was implemented to model the interface between fiber and matrix. The damage behavior of fiber was simulated using the ABAQUS user subroutine to define a material’s mechanical behavior (UMAT). Both experimental and analytical results indicate that the hierarchical carbon fibers enhanced by aligned ZnO nanowires are effective in improving the key mechanical properties of hybrid fiber-reinforced composites.  相似文献   
44.
Secondary malignancies are a significant cause of non‐relapse mortality in patients who undergo allogeneic HCT. However, secondary liver cancer is rare, and ICC following HCT has never been reported in the literature. Secondary solid cancers typically have a long latency period, and cholangiocarcinoma is classically a malignancy occurring in older individuals. Here, we report the first case of secondary ICC, which presented just 3 years after HCT in a young adult with a history of childhood ALL. A 26‐year‐old male with history of precursor B‐cell ALL presented with asymptomatic elevated liver function tests 3 years after HCT. Laboratories were indicative of biliary obstruction. ERCP showed focal biliary stricturing of the common and left hepatic ducts. MRCP revealed left intrahepatic duct dilatation, suggestive of intrahepatic obstructing mass. Additional workup lead to a clinical diagnosis of ICC. The patient underwent left hepatectomy with extrahepatic bile duct resection and portal lymphadenectomy. Surgical pathology was consistent with moderately differentiated cholangiocarcinoma. Our case illustrates a rare SMN following HCT for ALL. It is the first case report of ICC occurring as a secondary cancer in this patient population. Although cholangiocarcinoma is characteristically diagnosed in the older population, it must remain on the differential for biliary obstruction in post‐HCT patients.  相似文献   
45.
The present study investigated the effects of aerial parts of Phlomis anisodonta methanolic extract (PAE) on streptozotocin (STZ)-induced diabetic rats by measuring fasting blood glucose, serum insulin, change in body weight, ferric reducing antioxidant power (FRAP), lipid peroxidation (LPO), and liver antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Male Wistar rats were randomly divided into six groups of six animals. Treatment of diabetic rats with oral administration of PAE at doses of 100, 200 and 400 mg kg(-1) for 10 days resulted in a significant reduction in fasting blood glucose, and an increase in serum insulin levels in comparison with diabetic control group. PAE also protected rats from STZ-induced loss in body weight. Hepatic FRAP increased and LPO in diabetic rats decreased after treatment by PAE at doses of 200 and 400 mg kg(-1). PAE-treated diabetic rats at three doses indicated a significant increase in hepatic SOD, CAT, and GPx activities. These results suggest that PAE is beneficial in the control of diabetes by reduction of blood glucose and increasing insulin levels and combating oxidative stress by activation of hepatic antioxidant enzymes.  相似文献   
46.
Objectives: To explore consumers’ attitudes towards, and expectations of, adherence support services in primary health care, specifically in community pharmacy; and to explore consumers’ attitudes towards the concept of concordance. Setting: An exploratory qualitative study conducted in Metropolitan Sydney, Australia. Method: Three focus group discussions with consumers on chronic therapy (n = 22) and two focus groups with consumer representatives (n = 15) were conducted in 2002. Consumer representatives were peer educators volunteering in an association which promotes quality use of medicines among elderly patients. All discussions were audio-taped, transcribed verbatim and thematically content analysed. Main outcome measures: Consumers’ experiences with adherence support services delivered by general practitioners and pharmacists, their expectations towards general practitioners’ and pharmacists’ role in adherence support; and attitudes towards concordance in consultations. Results: Participants expected an increased provision of medicine information and a reduction in the number of medications taken as the main strategies to promote adherence. They believed that once understandable information had been delivered, it was their responsibility to take their medications as prescribed. Yet participants frequently complained about the information received, especially from doctors. Only a subgroup of participants expected pharmacists to be involved in adherence support services. These participants generally relied on pharmacists for medicine information and were satisfied with the communication process when interacting with the pharmacists. All participants were positive about concordance, because they valued two-way communication and increased consideration of their needs and beliefs by healthcare professionals. However, they were hesitant about being involved in a shared treatment decision-making process. Many participants focused on concordance with doctors and identified barriers to the establishment of concordance: time pressures, financial constraints, the gap of competence and power between patients and doctors. Conclusions: Pharmacists should consider consumers’ needs for information and establishing concordance, as well as their expectations of the pharmacy profession, in delivering concordance based adherence support services. Given participants’ high demand for medicine information, an opportunity might exist for pharmacists to influence consumers’ expectations by offering information which is tailored towards their needs.  相似文献   
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Disseminated BCG infection is a rare complication of vaccination that occurs in patients with impaired immunity. In recent years, a series of inherited disorders of the IL-12-IFN- axis have been described that predispose affected individuals to disseminated disease caused by BCG, environmental Mycobacteria, and non-typhoidal Salmonella. The routine immunological work-up of these patients is normal and the diagnosis requires specific investigation of the IL-12-IFN- circuit. We report here the first two such patients originating from and living in Iran. The first child is two years old and suffers from complete IFN- receptor 2 deficiency and disseminated BCG infection. He is currently in clinical remission thanks to prolonged multiple antibiotic therapy. The other, a 28-year-old adult, suffers from IL-12p40 deficiency and presented with disseminated BCG infection followed by recurrent episodes of systemic salmonellosis. He is now doing well. A third patient of Iranian descent, living in North America, was reported elsewhere to suffer from IL-12R1 deficiency. These three patients thus indicate that various inherited defects of the IL-12-IFN- circuit can be found in Iranian people. In conclusion we recommend to consider the disorders of the IL-12-IFN- circuit in all patients with severe BCG infection, disseminated environmental mycobacterial disease, or systemic non-typhoidal salmonellosis, regardless of their ethnic origin and country of residence.  相似文献   
49.

Background

Recently, it has been observed that Video Display Terminals (VDTs) usage for long periods can cause some dermatological manifestations on the face. An analytical cross-sectional study was designed in order to determine this relationship.

Methods

In this study, 600 office workers were chosen randomly from an organization in Tehran (Iran). The subjects were then divided into two groups based on their exposure to VDTs. 306 workers were considered exposure negative (non VDT user) who worked less than 7 hours a week with VDTs. The remainders 294 were exposure-positive, who worked 7 hours or more with VDTs. The frequency of dermatologic manifestations was compared in these two groups.

Results

In the exposure-positive and exposure-negative groups, the frequency of these dermatologic manifestations were 27 and 5 respectively. After statistical analysis, a P.value of < 0.05 was obtained indicating a statistically significant difference between these two groups for dermatological manifestations.

Conclusion

According to our study, there is a relationship between dermatologic manifestations on the face and exposure to VDTs.  相似文献   
50.
PURPOSE: Because retinal pigment epithelium (RPE) constitutively expresses class I major histocompatibility complex (MHC) molecules, and CD95 ligand and secretes immunosuppressive factors, the vulnerability of these cells to attack by immune T cells is open to question. This study was conducted to determine the vulnerability of allogeneic RPE to damage by specifically sensitized T cells, both in vivo within the subretinal space, and in vitro. METHOD: BALB/c lymphocytes presensitized to C57BL/6 antigens were injected into the subretinal space of eyes of C57BL/6 and gld/gld mice, and the eyes were examined clinically and histologically. RPE eyecups were produced from mouse eyes by removing the anterior segment and neuronal retina, leaving an intact monolayer of RPE. Sensitized BALB/c lymphocytes were placed in the RPE eyecup and incubated for 4 hours. The RPE layer of the eyecups was assessed by confocal microscopy for viability, after staining with propidium iodide and acridine orange. RESULT: Eyes that received T cells sensitized to C57BL/6 antigens displayed a circumscribed patch of persistent choroidal "whitening" clinically and a disrupted RPE cell layer histologically at the injection site at 5 days after injection. By 14 days, only RPE cells at the injection site were lost. RPE in eyecup preparations was relatively resistant in vitro to cytolysis by sensitized T cells, whether the eyecups were obtained from CD95-deficient or wild-type mice. CONCLUSIONS: RPE monolayers, both in vivo and in vitro, are relatively resistant to immune-mediated attack by specifically sensitized T cells. This relative lack of vulnerability is independent of the expression of CD95 ligand by target RPE cells and implies that immune barriers to acceptance of allogeneic RPE transplants may be less than if transplanted cells are from nonocular tissues.  相似文献   
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