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Anxiety disorders and anxiety symptoms are highly prevalent in the general population and more so in the medically ill. They have a number of negative consequences for these patients and may worsen the outcome of the medical illness and increase health care utilization. In the evaluation of these patients, it is of paramount importance to identify the etiology of the anxiety and, in particular, to differentiate primary from secondary anxiety. Management includes medications (especially benzodiazepines and selective serotonin reuptake inhibitors) and psychotherapy (particularly cognitive-behavioral therapy).  相似文献   
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BACKGROUND: The periodontal ligament (PDL) is a soft tissue interposed between the tooth and the alveolar bone. It is responsible for transmission of forces in vivo; this promotes bone remodeling. The purpose our study was to use fractal analysis to quantify the complex morphology of the PDL-bone interface. METHODS: We used Scion Image (Scion Corp, Frederick, Md) and Benoit fractal analysis (Tru Soft International, St. Petersburg, Fla) programs to calculate the fractal dimension of the PDL-bone interface in rats via the box-counting method. Rats in the experimental groups received an initial force of 0.1N or 0.5N with customized springs for 6 hours. RESULTS: Our studies showed an increase in normal fractal dimension at the root apices of the rats' maxillary molars. We also found evidence that the fractal dimension varies along the entire root length from the apex to the cementoenamel junction. CONCLUSIONS: Mechanical loading might lead to an increase in fractal dimension at the PDL-bone interface apart from mechanisms of bone cell directed remodeling. These changes in fractal dimension are proportional to loading and could provide a new parameter for force determination in orthodontic tooth movement.  相似文献   
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Dendritic cells and autoimmunity   总被引:7,自引:0,他引:7  
Dendritic cells (DC) are professional antigen-presenting cells that are specialized in the uptake of antigens and their transport from peripheral tissues to the lymphoid organs. Because of their capacity to stimulate naive T cells, DC have a central role in the initiation of primary immune responses and are considered promising tools and targets for immunotherapy. Emerging data suggest a role for DC in initiating autoimmune attacks. Direct analysis of DC phenotypes and DC-T-cell interactions in rodent and human autoimmune diseases should shed light on how pathogenesis occurs, and suggest novel avenues of treatment aimed at alleviating deviant DC function.  相似文献   
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Current treatment modalities available for hepatitis B virus (HBV) or hepatitis C virus (HCV) infections are not efficient. The enormous disease burden caused by these two infections makes the development of novel therapies critical. For HCV, the development of an effective vaccine is urgent in view of the escalating number of infected individuals. Molecular therapies for HBV and HCV infection can be directed at reducing viral load by interfering with the life cycle of the viruses or at generating immune response against viral epitopes. The antiviral approaches consist of the delivery or expression of antisense RNAs, ribozymes or dominant negative proteins. Viral biology can be interrupted by attacking various potential targets within the two viruses. DNA-based vaccination strategies are being explored for both prevention and treatment of these diseases. Both non-viral and recombinant viral vectors are being developed for safe, effective and long-term gene transfer to the liver. Although no "ideal" vector is available at this time, the ingenuity of numerous investigators is leading to the improvement of the vector systems, promising successful application of gene therapy to the prevention and treatment of viral hepatitis in the foreseeable future.  相似文献   
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Alveolar overdistension during mechanical ventilation causes leukocyte sequestration, leading to lung injury. However, underlying endothelial cell (EC) mechanisms are undefined. In a new approach, we exposed isolated blood-perfused rat lungs to high tidal volume ventilation (HV) for 2 h, then obtained fresh lung endothelial cells (FLEC) by immunosorting at 4 degrees C. Immunoblotting experiments indicated that as compared with FLEC derived from lungs ventilated at low volume (LV), HV markedly enhanced tyrosine phosphorylation (TyrP). The tyrosine kinase blocker, genistein, inhibited this response. HV also induced focal adhesion (FA) formation in FLEC, as detected by immunofluorescent aggregates of the alpha(v)beta(3) integrin that co-localized with aggregations of focal adhesion kinase (FAK). Immunoprecipitation and blotting experiments revealed that HV increased TyrP of the FA protein, paxillin. In addition, HV induced a paxillin-associated P-selectin expression on FLEC that was also inhibited by genistein. However, HV did not increase lung water. These results indicate that in HV, EC signaling in situ causes FA formation and induces TyrP-dependent P-selectin expression. These signaling mechanisms may promote leukocyte-mediated responses in HV.  相似文献   
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The COVID-19 pandemic has exposed the medical and social vulnerability of an unprecedented number of people. Consequently, there has never been a more important time for clinicians to engage patients in advance care planning (ACP) discussions about their goals, values, and preferences in the event of critical illness. An evidence-based communication tool—the Serious Illness Conversation Guide—was adapted to address COVID-related ACP challenges using a user-centered design process: convening relevant experts to propose initial guide adaptations; soliciting feedback from key clinical stakeholders from multiple disciplines and geographic regions; and iteratively testing language with patient actors. With feedback focused on sharing risk about COVID-19–related critical illness, recommendations for treatment decisions, and use of person-centered language, the team also developed conversation guides for inpatient and outpatient use. These tools consist of open-ended questions to elicit perception of risk, goals, and care preferences in the event of critical illness, and language to convey prognostic uncertainty. To support use of these tools, publicly available implementation materials were also developed for clinicians to effectively engage high-risk patients and overcome challenges related to the changed communication context, including video demonstrations, telehealth communication tips, and step-by-step approaches to identifying high-risk patients and documenting conversation findings in the electronic health record. Well-designed communication tools and implementation strategies can equip clinicians to foster connection with patients and promote shared decision making. Although not an antidote to this crisis, such high-quality ACP may be one of the most powerful tools we have to prevent or ameliorate suffering due to COVID-19.  相似文献   
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Takayasu’s arteritis (TA) is a granulomatous large vessel vasculitis more commonly seen in India. The vascular inflammation in TA results in stenoses of affected vessels. Usually this is a slow process with good collateral circulation; only rarely does critical limb ischemia result. We present two patients of TA who presented with gangrene of extremities, and review eight prior such patients reported in the literature. With appropriate diagnosis and treatment with oral corticosteroids and low-dose aspirin, none of our patients had recurrence at a mean follow-up of 3.8 ± 2.8 years. Although rare, TA can present with gangrene and rheumatologists need to be aware of this unusual but limb-threatening manifestation of TA to institute appropriate therapy in a timely manner.  相似文献   
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