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51.
Wide-field specular microscopy, slit-lamp examination, and pachometry were performed on 22 successful hard contact lens wearers and 22 controls matched for age, race, sex, and refractive error. A minimum of 600 cells per control and 1200 per contact lens wearer were manually digitized from the specular photomicrographs. Frequency distributions of cell areas were compared between the two groups using the parameters of mean, median, standard deviation, coefficient of variation, skewness and kurtosis. Slit-lamp examination was normal and there was no significant difference in corneal thickness between the patient group and the control group. Comparison of mean, median, and standard deviation also revealed no significant difference, but skewness (P less than .001), kurtosis (P less than .001) and coefficient of variation (P less than .004) were greater in the hard contact lens wear group. Hard contact lens wearing time correlated with increasing pleomorphism (P less than .05). Specular microscopy also revealed morphologic changes including deep stromal striae, intra- and extracellular "blackout" areas, and clustering of extremely small and large cells. The possible relationship between endothelial hypoxia and structural stromal changes are discussed.  相似文献   
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Background: The coronavirus disease 2019 (COVID-19) pandemic has increased the already high levels of stress that higher education students experience. Stress influences health behaviors, including those related to dietary behaviors, alcohol, and sleep; yet the effects of stress can be mitigated by resilience. To date, past research studying the connections between dietary behaviors, alcohol misuse, sleep, and resilience commonly investigated singular relationships between two of the constructs. The aim of the current study was to explore the relationships between these constructs in a more holistic manner using mediation and moderation analyses. Methods: Higher education students from China, Ireland, Malaysia, South Korea, Taiwan, the Netherlands, and the United States were enrolled in a cross-sectional study from April to May 2020, which was during the beginning of the COVID-19 pandemic for most participants. An online survey, using validated tools, was distributed to assess perceived stress, dietary behaviors, alcohol misuse, sleep quality and duration, and resilience. Results: 2254 students completed the study. Results indicated that sleep quality mediated the relationship between perceived stress and dietary behaviors as well as the relationship between perceived stress and alcohol misuse. Further, increased resilience reduced the strength of the relationship between perceived stress and dietary behaviors but not alcohol misuse. Conclusion: Based on these results, higher education students are likely to benefit from sleep education and resilience training, especially during stressful events.  相似文献   
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Good nutritional support is crucial for the immune system to fight against coronavirus disease 2019 (COVID-19). However, in the context of a pandemic with a highly transmissible coronavirus, implementation of nutrition practice may be difficult. A multicenter electronic survey involving 62 dieticians was conducted, in order to understand barriers associated with dieticians’ adherence to nutrition guidelines for hospitalized COVID-19 patients in Indonesia. 69% of dieticians felt under stress when performing nutrition care, and 90% took supplements to boost their own immunity against the coronavirus. The concerns related to clinical practice included a lack of clear guidelines (74%), a lack of access to medical records (55%), inadequate experience or knowledge (48%), and a lack of self-efficacy/confidence (29%) in performing nutritional care. Half (52%) of the dieticians had performed nutrition education/counseling, 47% had monitored a patient’s body weight, and 76% had monitored a patient’s dietary intake. An adjusted linear regression showed that guideline adherence independently predicted the dieticians’ nutrition care behaviors of nutrition counselling (ß: 0.24 (0.002, 0.08); p = 0.04), and monitoring of body weight (ß: 0.43 (0.04, 0.11); p = 0.001) and dietary intake (ß: 0.47(0.03, 0.10); p = 0.001) of COVID-19 patients. Overall, adherence to COVID-19 nutrition guidelines is associated with better nutritional management behaviors in hospitalized COVID-19 patients.  相似文献   
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BackgroundPatients with neuroblastoma, a common childhood malignancy, often have poor prognosis. It is mandatory to develop an accurate and efficient diagnostic tool for neuroblastomas, so that the treatment can be started early. Graphene quantum dot (GQD), a nanomaterial, can be used to carry proteins, genetic materials, or drugs. GD2, a disialoganglioside, is a surface antigen expressed on neuroblastoma. This study investigated the in vivo targeting and imaging of neuroblastomas using GD2-targeting GQDs.MethodsGQDs were synthesized and conjugated with anti-GD2 antibody (anti-GD2/GQDs). In vitro cytotoxicity of GQDs and anti-GD2/GQDs was studied in human neuroblastoma cells by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide)-based colorimetric assay. The tumor tracking and imaging of anti-GD2/GQDs in mice were investigated by in vivo imaging system (IVIS).ResultsTreatment with GQDs or anti-GD2/GQDs induced no or mild cytotoxicity in fibroblasts and neuroblastoma cells. After co-incubation, GQDs and anti-GD2/GQDs were located in the cytoplasm and nucleus of neuroblastoma cells, with GQDs showing a blue fluorescence and anti-GD2/GQDs an orange/red emission. The IVIS images demonstrated accumulation of the fluorescence of anti-GD2/GQDs in the subcutaneous tumors in mice 24 h after intravenous injection of anti-GD2/GQDs.ConclusionsAnti-GD2/GQDs may potentially be used for the targeting and imaging of neuroblastomas in vivo.  相似文献   
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BackgroundThyroid surgeons are offering their patients less aggressive diagnostic and therapeutic management strategies for thyroid nodules and low-risk thyroid cancer in an effort to decrease overdiagnosis and overtreatment of indolent disease. Explaining the rationale for less aggressive management plans requires physicians to be effective communicators. We aimed to assess the communication skills of thyroid surgeons with the Makoul Communication Assessment Tool and to identify risk factors for poor communication.MethodsNew adult patients with thyroid nodules or thyroid cancer presenting to a single tertiary-referral endocrine surgery clinic were enrolled from July 2018 through December 2019. Patients were administered the Communication Assessment Tool immediately after their clinical encounter. Outlier communication scores were identified, and clinical characteristics were compared between outlier and nonoutlier groups.ResultsA total of 107 patients completed the Communication Assessment Tool. Mean (standard deviation) total and top box scores were 67 (6) and 86% (29%), respectively. Twenty-five patients (23%) were in the low-outlier group, defined by a total score below 67.5/70 or top box score below 82.25%. Other race and non-Hispanic patients (versus white race) were more likely low outliers (odds ratio 3.58, P = .048). The lowest scoring Communication Assessment Tool item overall was “the doctor encouraged me to ask questions” (78.5% top box).ConclusionWe found communication to be perceived as excellent in the majority of patients; however, an opportunity for improvement was identified in 29% of participants. Significant differences in race and ethnicity between low outlier and nonoutlier communication score patients were observed, which warrants additional investigation. These findings support the utility of the Communication Assessment Tool in studying the effectiveness of communication improvement initiatives.  相似文献   
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The hERG channel has an unusually long (39 amino acids) extracellular loop between the transmembrane S5 segment and the pore region that may play a role in channel function. We explored this possibility by mutating two histidine residues in this region (H578 and H587, referred to as H1 and H2) to various residues and examined the resulting changes in channel function. Both positions could tolerate drastic changes in side-chain properties (proline, cysteine, glutamate and lysine), indicating that they are solvent exposed. None of the H1 mutations affected hERG channel function. On the other hand, although replacing H2 with glutamate had little or no effect on hERG properties, putting a proline or lysine at this position disrupted the C-type inactivation process and the pore's K selectivity. There was also a hyperpolarizing shift in the voltage dependence of activation. The phenotype of the H2C mutant was similar to that of H2P or H2K. However, dithiothreitol (DTT, a thiol-reducing agent) treatment converted the H2C phenotype to that of the wild-type channel. These observations suggest that the peptide backbone conformation around position 587 in the extracellular S5-P loop of hERG channel can affect the channel's gating and ion selectivity functions.  相似文献   
60.
The term of "cloacogenic anal carcinoma", "cloacogenic zone" and "cloacal membrane" have been widely used, but the term of "inflammatory cloacogenic polyp" (ICP) was first applied and published by Lobert PF and Henry DA in 1981. Here we present three cases of ICP to stress its inflammatory property, predilection to invade cloacogenic zone of anus and polypoid shape, and to differentiate it from its related lesions as concise as possible.  相似文献   
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