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The role of integrins in osteoclast function   总被引:3,自引:0,他引:3  
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13.
OBJECTIVE AND IMPORTANCE: True duplication of the A1 segment of the anterior cerebral artery is extremely rare, as is finding a true A1 segment saccular aneurysm. We report the angiographic and surgical findings of such a case with the additional association of a hypoplastic ipsilateral M1 segment of the middle cerebral artery. CLINICAL PRESENTATION: A 68-year-old man presented with a Hunt and Hess Grade II subarachnoid hemorrhage and symptoms of headache, nuchal rigidity, and facial paresis. INTERVENTION: Angiographic evaluation with superselective exploration revealed a small ruptured aneurysm located on a duplicated hypoplastic A1 segment of the left anterior cerebral artery with associated middle cerebral artery stenosis and secondary early moyamoya changes. Surgical clipping of the aneurysm was performed successfully while sparing the hypoplastic A1 segment. CONCLUSION: A1 aneurysms occurring on a duplicated anterior cerebral artery segment probably develop from a congenital weakness of the parent vessel and increased local shear stress. Superselective angiography was helpful in the preoperative planning and facilitated the decision to treat with surgical clipping instead of embolization.  相似文献   
14.
Epidemiology of pneumothorax in England   总被引:9,自引:0,他引:9       下载免费PDF全文
BACKGROUND: Little is known of the epidemiology of pneumothorax. Routinely available data on pneumothorax in England are described. METHODS: Patients consulting in primary care with a diagnosis of pneumothorax in each year from 1991 to 1995 inclusive were identified from the General Practice Research Database (GPRD). Emergency hospital admissions for pneumothorax were identified for the years 1991-4 from the Hospital Episode Statistics (HES) data. Mortality data for England & Wales were obtained for 1950-97. Analyses of pneumothorax rates by age and sex were performed for all data sources. Seasonal and geographical analyses were carried out for the HES data. RESULTS: The overall person consulting rate for pneumothorax (primary and secondary combined) in the GPRD was 24. 0/100 000 each year for men and 9.8/100 000 each year for women. Hospital admissions for pneumothorax as a primary diagnosis occurred at an overall incidence of 16.7/100 000 per year and 5.8/100 000 per year for men and women, respectively. Mortality rates were 1. 26/million per year for men and 0.62/million per year for women. The age distribution in both men and women showed a biphasic distribution for both GP consultations and hospital admissions. Deaths showed a single peak with highest rates in the elderly. There was an urban-rural trend observed for hospital admissions in the older age group (55+ years) with admission rates in the conurbations significantly higher than in the rural areas. Analysis for trends in mortality data for 1950-97 showed a striking increase in the death rate for pneumothorax in those aged 55+ years between 1960 and 1990, with a steep decline in the 1990s. Mortality in the younger age group (15-34 years) remained low and constant. CONCLUSION: There is evidence of two epidemiologically distinct forms of spontaneous pneumothorax in England. The explanation for the rise and fall in mortality for secondary pneumothorax is obscure.  相似文献   
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16.
In order to stimulate antigen presentation and T cell activity against cancer, we treated three different tumor models in mice with the monoclonal antibodies anti-CD40 plus anti-CD137 (BiMab). In a subcutaneous transplantable MC38 colon cancer model, there was significant enhancement in the survival of mice following BiMab treatment. Anti-CD40 has shown considerable success against lymphoma in previous studies by other investigators, and we also showed in this study that, in a model of Eμ-Myc lymphoma, there was a statistically significant enhancement of survival of mice following BiMab treatment. Following the success of the BiMab treatment in the previous two models, we wished to determine if it would be successful in a mouse model of multiple myeloma. Firstly, we tested a transplantable model of disease in which multiple myeloma cells derived from Vk*MYC mice were injected intravenously. A minor proportion of anti-CD137 and BiMab treated mice experienced prolongation of life beyond 250 days. Then we tested the therapy in a spontaneously occurring multiple myeloma model, in Vk*MYC transgenic mice. The majority of mice treated survived longer than control mice, although statistical significance was not demonstrated.  相似文献   
17.
For the first time, activated carbon from a durian shell (ACDS) activated by H2SO4 was successfully synthesized in the present study. The fabricated ACDS has a porous surface with a specific surface area of 348.0017 m2·g−1, average capillary volume of 0.153518 cm3·g−1, the average pore diameter of 4.3800 nm; ash level of 55.63%; humidity of 4.74%; density of 0.83 g·cm−3; an iodine index of 634 mg·g−1; and an isoelectric point of 6.03. Several factors affecting Methylene Blue (MB) adsorption capacity of ACDS activated carbon was investigated by the static adsorption method, revealing that the adsorption equilibrium was achieved after 90 min. The best adsorbent pH for MB is 7 and the mass/volume ratio is equal to 2.5 g·L−1. The MB adsorption process of ACDS activated carbon follows the Langmuir, Freundlich, Tempkin, and Elovich isotherm adsorption model, which has determined the maximum adsorption capacity for MB of ACDS as qmax = 57.47 mg·g−1. The MB adsorption process of ACDS follows the of pseudo-second-order adsorption kinetic equation. The Weber and Morris Internal Diffusion Model, the Hameed and Daud External Diffusion Model of liquids have been studied to see if the surface phase plays any role in the adsorption process. The results of thermodynamic calculation of the adsorption process show that the adsorption process is dominated by chemical adsorption and endothermic. The obtained results provide an insight for potential applications of ACDS in the treatment of water contaminated by dyes.  相似文献   
18.
Osteoporosis is a common bone health disorder in hemodialysis patients that is linked with a higher morbidity and mortality rate. While previous studies have explored the associated factors of osteoporosis, there is a lack of studies investigating the impacts of health literacy (HL) and digital healthy diet literacy (DDL) on osteoporosis. Therefore, we aimed to investigate the associations of HL, DDL, and other factors with osteoporosis among hemodialysis patients. From July 2020 to March 2021, a cross-sectional study was conducted on 675 hemodialysis patients in eight hospitals in Vietnam. The data were collected by using the osteoporosis self-assessment tool for Asians (OSTA) and the 12-item short form of the health literacy questionnaire (HLS-SF12) on digital healthy diet literacy (DDL) and hemodialysis dietary knowledge (HDK). In addition, we also collected information about the socio-demographics, the clinical parameters, the biochemical parameters, and physical activity. Unadjusted and adjusted multinomial logistic regression models were utilized in order to investigate the associations. The proportion of patients at low, medium, and high levels of osteoporosis risk was 39.6%, 40.6%, and 19.8%, respectively. In the adjusted models, women had a higher likelihood of osteoporosis risk than men (odds ratio, OR, 3.46; 95% confidence interval, 95% CI, 1.86, 6.44; p < 0.001; and OR, 6.86; 95% CI, 2.96, 15.88; p < 0.001). The patients with rheumatoid arthritis (OR, 4.37; 95% CI, 1.67, 11.52; p = 0.003) and stomach ulcers (OR, 1.95; 95% CI, 1.01, 3.77; p = 0.048) were more likely to have a higher likelihood of osteoporosis risk than those without. The patients who had a higher waist circumference (WC), HL, and DDL were less likely to have a medium level of osteoporosis risk (OR, 0.95; 95% CI, 0.92, 0.98; p = 0.004; OR, 0.92; 95% CI, 0.88, 0.96; p < 0.001; OR, 0.96; 95% CI, 0.93, 0.99; p = 0.017, respectively) and a high level of osteoporosis risk (OR, 0.93; 95% CI, 0.89, 0.97; p = 0.001; OR, 0.89; 95% CI, 0.84, 0.94; p < 0.001; OR, 0.95; 95% CI, 0.91, 0.99; p = 0.008, respectively) compared with a low level of osteoporosis risk and to those with a lower WC, HL, and DDL. In addition, higher levels of hemoglobin (Hb) (OR, 0.79; 95% CI, 0.66, 0.95; p = 0.014), hematocrit (Hct) (OR, 0.95; 95% CI, 0.92, 0.99; p = 0.041), albumin (OR, 0.91; 95% CI, 0.83, 0.99; p = 0.030), and education (OR, 0.37; 95% CI, 0.16, 0.88; p = 0.025) were associated with a lower likelihood of a high level of osteoporosis risk. In conclusion, osteoporosis risk is highly prevalent in hemodialysis patients. Improved HL, DDL, education, WC, albumin, Hb, and Hct levels should be considered in preventing hemodialysis patients from developing osteoporosis.  相似文献   
19.
BackgroundSchool principals have been reported to have a higher prevalence of burnout and psychological problems than their colleagues. During the pandemic, extra workload and pressure from unprecedented situations potentially cause fear, stress and depression. Therefore, we aimed to explore associated factors of stress, fear of COVID-19 (F-CoV-19S) and depressive symptoms among school principals.MethodsA cross-sectional online survey was conducted in Taiwan from 23 June to 16 July 2021. Data of 413 school principals were collected, including socio-demographic factors, COVID-19-related factors, work-related information, health status, sense of coherence (SoC), health literacy (HL), F-CoV-19S, stress and depression. Multiple linear and logistic regression models were utilized to explore associations.ResultsSchool principals with symptoms like COVID-19 (S-COVID-19-S), or with health-related activity limitations had a higher score of stress (B = 0.92; p = .039) (B = 1.52; p < .001) and a higher depression likelihood (OR = 3.38; p < .001) (OR = 3.06; p < .001), whereas those with a better SoC had a lower stress score (B = −1.39; p < .001) and a lower depression likelihood (OR = 0.76; p = .020). School principals confusing about COVID-19-related information had a higher score of stress (B = 2.47; p < .001) and fear (B = 3.77; p < .001). The longer working time was associated with a higher fear score (B = 1.69; p = .006). Additionally, school principals with a higher HL score had a lower stress score (B = −1.76; p < .001), a lower fear score (B = −1.85; p < .001) and a lower depression likelihood (OR = 0.53; p = .043).ConclusionsHealth-related activity limitations, S-COVID-19-S, COVID-19-related information confusion and longer working hours were positively associated with at least one mental health problem (e.g. stress, fear and depression), whereas better SoC and HL showed the benefits to mitigate fear, stress and depressive symptoms in school principals. Our study provides evidence for appropriate strategies to improve principals’ mental health during the pandemic.

Key messages:

  • School principals with health-related activity limitations or with symptoms like COVID-19 were more likely to be stressed and depressed.
  • Higher levels of stress and fear were observed in school principals who confused about COVID-19-related information, and who had longer working time than before the pandemic.
  • Better sense of coherence and higher health literacy could potentially mitigate the fear, stress and depressive symptoms in school principals.
  相似文献   
20.
Transport properties of the halogeno-alkali oxides A3OX (A = Li, Na, X = Cl, Br) nanocrystalline samples with the presence of ∑3(111) grain boundaries were computed using large-scale molecular dynamic simulations. Results on the diffusion/conduction process show that these nanocrystalline samples are characterized with higher activation energies as compared to previous theoretical studies, but closer to experiment. Such a performance can be attributed to the larger atomic density at the ∑3(111) grain boundary regions within the nanocrystals. Despite a minor deterioration of transport properties of the mixed cation Li2NaOX and Na2LiOX samples, these halogeno-alkali oxides can also be considered as good inorganic solid electrolytes in both Li- and Na-ion batteries.

Transport properties of the halogeno-alkali oxides A3OX (A = Li, Na, X = Cl, Br) nanocrystalline samples with the presence of ∑3(111) grain boundaries were computed using large-scale molecular dynamic simulations.  相似文献   
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