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Most disaster plans depend on using emergency physicians, nurses, emergency department support staff, and out-of-hospital personnel to maintain the health care system's front line during crises that involve personal risk to themselves or their families. Planners automatically assume that emergency health care workers will respond. However, we need to ask: Should they, and will they, work rather than flee? The answer involves basic moral and personal issues. This article identifies and examines the factors that influence health care workers' decisions in these situations. After reviewing physicians' response to past disasters and epidemics, we evaluate how much danger they actually faced. Next, we examine guidelines from medical professional organizations about physicians' duty to provide care despite personal risks, although we acknowledge that individuals will interpret and apply professional expectations and norms according to their own situation and values. The article goes on to articulate moral arguments for a duty to treat during disasters and social crises, as well as moral reasons that may limit or override such a duty. How fear influences behavior is examined, as are the institutional and social measures that can be taken to control fear and to encourage health professionals to provide treatment in crisis situations. Finally, the article emphasizes the importance of effective risk communication in enabling health care professionals and the public to make informed and defensible decisions during disasters. We conclude that the decision to stay or leave will ultimately depend on individuals' risk assessment and their value systems. Preparations for the next pandemic or disaster should include policies that encourage emergency physicians, who are inevitably among those at highest risk, to "stay and fight."  相似文献   
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Sensitive Schistosoma japonicum detection methods are needed to progress from schistosomiasis control to elimination. The sensitivity of the Kato-Katz thick smear and miracidium hatching tests decrease with infection intensity and serological tests cannot always identify current infections. We evaluated a fecal polymerase chain reaction (PCR) assay to detect S. japonicum infection in 106 humans and 8 bovines in China. PCR was highly sensitive, detecting S. japonicum DNA at 0.5 eggs/g of stool. Comparing PCR examination of a single stool sample to the miracidium hatching test using three consecutive stool samples, more humans were hatching test positive (20%) than PCR positive (15%). However, two individuals were PCR positive in a village where no infections were detected by coprological methods. The sensitivity of PCR makes it a promising tool for schistosomiasis diagnostics and screening, although egg shedding variability and stool sample size present challenges for any detection method in low-transmission areas.  相似文献   
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Background

The optimal time to initiate venous thromboembolism pharmacoprophylaxis after blunt abdominal solid organ injury is unknown.

Methods

Postinjury coagulation status was characterized using thromboelastography (TEG) in trauma patients with blunt abdominal solid organ injuries; TEG was divided into 12-hour intervals up to 72 hours.

Results

Forty-two of 304 patients (13.8%) identified underwent multiple postinjury thromboelastographic studies. Age (P = .45), gender (P = .45), and solid organ injury grade (P = .71) were similar between TEG and non-TEG patients. TEG patients had higher Injury Severity Scores compared with non-TEG patients (33.2 vs 18.3, respectively, P < .01). Among the TEG patients, the shear elastic modulus strength and maximum amplitude values began in the normal range within the first 12-hour interval after injury, increased linearly, and crossed into the hypercoagulable range at 48 hours (15.1 ± 1.9 Kd/cs and 57.6 ± 1.6 mm, respectively; P < .01, analysis of variance).

Conclusions

Patients sustaining blunt abdominal solid organ injuries transition to a hypercoagulable state approximately 48 hours after injury. In the absence of contraindications, pharmacoprophylaxis should be considered before this time for effective venous thromboembolism prevention.  相似文献   
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Radial glia‐like cells (RGCs) are the hypothesized source of adult hippocampal neurogenesis. However, the current model of hippocampal neurogenesis does not fully incorporate the in vivo heterogeneity of RGCs. In order to better understand the contribution of different RGC subtypes to adult hippocampal neurogenesis, we employed widely used transgenic lines (Nestin‐CreERT2 and GLAST::CreERT2 mice) to explore how RGCs contribute to neurogenesis under basal conditions and after stimulation and depletion of neural progenitor cells. We first used these inducible fate‐tracking transgenic lines to define the similarities and differences in the contribution of nestin‐ and GLAST‐lineage cells to basal long‐term hippocampal neurogenesis. We then explored the ability of nestin‐ and GLAST‐lineage RGCs to contribute to neurogenesis after experimental manipulations that either ablate neurogenesis (i.c.v. application of the anti‐mitotic AraC, cytosine‐β‐D‐arabinofuranoside) or stimulate neurogenesis (wheel running). Interestingly, in both ablation and stimulation experiments, labeled RGCs in GLAST::CreERT2 mice appear to contribute to neurogenesis, whereas RGCs in Nestin‐CreERT2 mice do not. Finally, using NestinGFP reporter mice, we expanded on previous research by showing that not all RGCs in the adult dentate gyrus subgranular zone express nestin, and therefore RGCs are antigenically heterogeneous. These findings are important for the field, as they allow appropriately conservative interpretation of existing and future data that emerge from these inducible transgenic lines. These findings also raise important questions about the differences between transgenic driver lines, the heterogeneity of RGCs, and the potential differences in progenitor cell behavior between transgenic lines. As these findings highlight the possible differences in the contribution of cells to long‐term neurogenesis in vivo, they indicate that the current models of hippocampal neurogenesis should be modified to include RGC lineage heterogeneity. © 2013 Wiley Periodicals, Inc.  相似文献   
36.
BACKGROUND: Research to address clinical symptoms and the way they change over time in an individual is of paramount importance to healthcare researchers who are interested in improving the quality of life for ill patients. However, typical statistical methods that rely on means can obscure individual trajectories of change. Visual graphical analysis (VGA) is a technique that can provide researchers with an alternative method of quantitative statistical analysis that is more sensitive to individual change and variation. OBJECTIVES: To (a) describe the use of VGA as a method to evaluate longitudinal data, (b) discuss challenges to using this method, and (c) offer recommendations for future research in which the method could be implemented. APPROACH: This methodological article uses data collected from a primary study to present the method of VGA. Daily self-reported sore mouth severity scores from patients receiving outpatient chemotherapy were used in this VGA. The steps of VGA include (a) determining inclusion criteria, (b) managing missing data, (c) creating visual graphs, (d) identifying specific patterns, and (e) performing validation and verification. DISCUSSION: Because symptoms occur differently for each patient, this method allows researchers to see symptom trajectories on an individual basis. Creation and analysis of longitudinal graphs could be used also to inspect other symptoms or clinical problems such as headaches, fatigue, constipation, nausea and vomiting, and psychological difficulties. The value of VGA is that it allows a researcher to study the patterns of an individual's experience, as opposed to averaging all individuals' responses over time. Although graphical analysis is exploratory in nature, it may lead to enhanced longitudinal recognition of symptoms that might not be identified otherwise by quantitative data analysis using summary statistics.  相似文献   
37.
The possible pronociceptive role of peripheral and spinal 5-HT7 receptors in the formalin test was assessed. Local administration of 5-HT7 (SB-269970, 2.5-77.1 nmol/paw), but not 5-HT(1A) (WAY-100635, 1-60 nmol/paw), receptor antagonist significantly reduced formalin-induced flinching. Local 5-hydroxytryptamine (5-HT, 3-100 nmol/paw) or 5-carboxamidotryptamine (5-CT, 0.3-3 nmol/paw) (a 5-HT7/1A receptor agonist) augmented, in a dose-dependent manner, 0.5% formalin-induced nociceptive behavior. The local pronociceptive effect of 5-HT or 5-CT was significantly reduced by SB-269970 (25 and 77.1 nmol/paw), but not by WAY-100635 (10 nmol/paw). 5-HT7 receptors were observed in myelinated and unmyelinated axons of the digital nerves in rat hindpaw. Intrathecal SB-269970 (2.5-77.1 nmol/rat) or WAY-100635 (1-50 nmol/rat) did not modify 1% formalin-induced nociceptive behavior. Spinal 5-HT (25-200 nmol/rat) significantly reduced formalin-induced flinching behavior during phase 2. At lower doses (0.1-3 nmol/rat) intrathecal 5-CT dose-dependently increased flinching during phase 2. In contrast, higher doses (10-30 nmol/rat) of 5-CT reduced formalin-induced nociceptive behavior during both phases. The spinal pronociceptive effect of 5-CT was reduced by SB-269970 (7.7-77 nmol/rat), but not by WAY-100635 (10 nmol/rat). In addition, the spinal antinociceptive effect of 5-CT was partially reversed by WAY-100635 (10 nmol/rat). The spinal antinociceptive effect of 5-HT was unaffected either by SB-269970 (77 nmol/rat) or WAY-100635 (10 nmol/rat). Data suggest that 5-HT7, but not 5-HT1A, receptors play a pronociceptive role in peripheral and spinal sites in the rat formalin test.  相似文献   
38.
Clostridium perfringens enterotoxin (CPE) is a three-domain polypeptide, which binds to Claudin-3 and Claudin-4 with high affinity. Because these receptors are highly differentially expressed in many human tumors, claudin-3 and claudin-4 may provide an efficient molecular tool to specifically identify and target biologically aggressive human cancer cells for CPE-specific binding and cytolysis. In this review we will discuss these surface proteins as targets for the detection and treatment of chemotherapy-resistant gynecologic malignancies overexpressing claudin-3 and -4 using CPE-based theranostic agents. We will also discuss the use of fluorescent c-CPE peptide in the operative setting for real time detection of micro-metastatic tumors during surgery and review the potential role of CPE in other medical applications.  相似文献   
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