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The lymphocytotoxic activity (LCA) of sera from patients with infectious mononucleosis (IM) was tested against lymphocytes under various experimental conditions. Firstly, lymphocytes from 11 healthy donors were preincubated with pools of normal human sera (NHS) or IM sera at 37°C and then tested for (a) reactivity with the same IM sera in a standard lymphocytotoxin assay at 15°C; (b) rosetting with various sheep erythrocyte (E) preparations (E, EA and EAC) and (c) stimulation by non-specific activators (phytohaemagglutinin, pokeweed mitogen and concanavalin A). These experiments showed that preincubation of normal cells with IM sera caused significant reduction in subsequent lymphocyte killing at 15°C (P<0·01) compared to unincubated cells or those preincubated with pooled NHS. There was no change in the binding of E, EA and EAC or mitogen stimulation following incubation. Culture of preincubated lymphocytes in lymphocytotoxin-free medium for 24 hr did not restore LCA at 15°C. Secondly, a pool of normal lymphocytes was incorporated into media containing either 2,4-dinitrophenol or sodium azide and tested for LCA against 11 acute IM sera and two NHS at both 15 and 37°C. No significant change in cell killing was observed at 15°C in the presence of these inhibitors, but there was a significant return of LCA at 37°C. Finally, normal lymphocytes and cells from two patients with IM were cultured at 37°C in lymphocytotoxin-free medium to determine the role of down-regulation of lymphocyte surface receptors in reducing autolymphocytotoxicity during the acute phase of the illness. There was no change in cell killing by IM sera after culture for 24 hr. These experiments show that lymphocytotoxic sera from patients with infectious mononucleosis interact with normal lymphocytes at 37°C without causing cell killing. This interaction caused a change in surface-binding characteristics that was not reversed by culture in ligand-free medium for 24 hr. Studies using metabolic inhibitors suggested that the failed lymphocytotoxicity at 37°C resulted, at least in part, from lymphocyte metabolism, although this did not inhibit the reaction between cytotoxic material and the lymphocyte surface.  相似文献   
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Journal of Public Health - Depression is a major morbidity and the most common mental disorder among the medical students in medical schools globally. Undergraduate students suffer stress more due...  相似文献   
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Transgender (trans) women experience barriers to access to HIV care, which result in their lower engagement in HIV prevention, treatment and support relative to cisgender people living with HIV. Studies of trans women's barriers to HIV care have predominantly focused on perspectives of trans women, while barriers are most often described at provider, organisation and/or systems levels. Comparing perspectives of trans women and service providers may promote a shared vision for achieving health equity. Thus, this qualitative study utilised focus groups and semi-structured interviews conducted 2018–2019 to understand barriers and facilitators to HIV care from the perspectives of trans women (n = 26) and service providers (n = 10). Barriers endorsed by both groups included: (a) anticipated and enacted stigma and discrimination in the provision of direct care, (b) lack of provider knowledge of HIV care needs for trans women, (c) absence of trans-specific services/organisations and (d) cisnormativity in sexual healthcare. Facilitators included: (a) provision of trans-positive trauma-informed care, (b) autonomy and choice for trans women in selecting sexual health services and (c) models for trans-affirming systems change. Each theme had significant overlap, yet nuanced perspective, between trans women and service providers. Specific recommendations to improve HIV care access for trans women are discussed. These recommendations can be used by administrators and service providers alike to work collaboratively with trans women to reduce barriers and facilitators to HIV care and ultimately to achieve health equity for trans women.  相似文献   
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Continued smoking in cancer patients is commonly observed in Jordan. In a country that exhibits some of the highest smoking rates globally, enhancing patient education regarding the value of smoking cessation for cancer care is vital. The objectives of our study were to describe sociodemographic and clinical factors associated with continued smoking in Jordanian smokers after a cancer diagnosis; to identify reasons for smoking and knowledge regarding smoking’s impact on care; to examine in a multivariable manner the factors associated with continued smoking, and to accordingly generate patient counseling recommendations. An interviewer-administered survey using the Theoretical Domains Framework was employed. Among 350 subjects (mean age 51.0, median 52.7), approximately 38% of patients had quit or were in the process of quitting; 61.7% remained smokers. Substantial knowledge gaps with regard to the impact of continued smoking on cancer care were observed. Remaining a smoker after diagnosis was associated with being employed, not receiving chemotherapy or surgery, having lower confidence in quitting, and having a lower number of identified reasons for smoking. Interventions to promote cessation in Jordanian cancer patients who smoke should focus on enhancing patient awareness about the impact of smoking in cancer care and raising perceived self-efficacy to quit.  相似文献   
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The development of cost-effective co-catalysts of high photocatalytic activity and recyclability is still a challenge in the energy transformation domain. In this study, 0D/2D Schottky heterojunctions, consisting of 0D ZnO and 2D Ti3C2, were successfully synthesized by the electrostatic self-assembling of ZnO nanoparticles on Ti3C2 nanosheets. In constructing these heterojunctions, Ti3C2 nanosheets acted as a co-catalyst for enhancing the transfer of excitons and their separation to support the photocatalytic response of ZnO. The as-prepared ZnO/Ti3C2 composites demonstrate an abbreviated charge transit channel, a huge interfacial contact area and the interfacial electrons’ transport potential. The extended optical response and large reactive area of the ZnO/Ti3C2 composite promoted the formation of excitons and reactive sites on the photocatalyst’s surface. The ZnO/Ti3C2 Schottky heterojunction showed significantly high photocatalytic activity for hydrogen production from a water–ethanol solution under the light illumination in the visible region. The hydrogen evolution overoptimized the ZnO/Ti3C2 composition with 30 wt.% of Ti3C2, which was eight times higher than the pristine ZnO. These findings can be helpful in developing 0D/2D heterojunction systems for photocatalytic applications by utilizing Ti3C2 as a low-cost co-catalyst.  相似文献   
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Background:Virtual reality (VR) is an advanced technique used in physical rehabilitation of neurological disorders, however the effects of VR on balance, gait, and motor function in people with Parkinson’s (PD) are still debated. Therefore, the systematic review aimed to determine the role of VR on motor function, balance and gait in PD patients.Methods:A comprehensive search to identify similar randomised controlled trials was conducted targeting 5 databases including Web of Science, PubMed, CINHAL, Cochrane Library, and Physiotherapy Evidence Database. A total of 25 studies were found eligible for this systematic review, and the methodological assessment of the quality rating of the studies was accomplished using the physiotherapy evidence database scale by 2 authors.Results:Out of the 25 included studies, 14 studies reported on balance as the primary outcome, 9 studies were conducted to assess motor function, and 12 assessed gait as the primary outcome. Most studies used the Unified Parkinson disease rating scale UPDRS (part-III) for evaluating motor function and the Berg Balance Scale as primary outcome measure for assessing balance. A total of 24 trials were conducted in clinical settings, and only 1 study was home-based VR trainings. Out of 9 studies on motor function, 6 reported equal improvement of motor function as compared to other groups. In addition, VR groups also revealed superior results in improving static balance among patient with PD.Conclusion:This systemic review found that the use of VR resulted in substantial improvements in balance, gait, and motor skills in patients with PD when compared to traditional physical therapy exercises or in combination with treatments other than physical therapy. Moreover, VR can be used as a supportive method for physical rehabilitation in patients of PD. However, the majority of published studies were of fair and good quality, suggesting a demand for high quality research in this area.  相似文献   
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This study was undertaken to determine the influence of Aloe vera (AV) on changes induced in pulmonary tissue of cigarette smoke (CS) inhaling mice. CS inhalation for 4 weeks caused pulmonary damage as evident by histoarchitectural alterations and enhanced serum and tissue lactate dehydrogenase (LDH) activities. CS inhalation also led to increased mucin production as revealed by mucicarmine and Alcian Blue‐Periodic Acid Schiff (AB‐PAS) staining. Studies on bronchoalveolar lavage fluid (balf) of CS exposed animals revealed structural changes in phospholipids and increase in surface tension when compared with control counterparts. These changes were accompanied by enhanced nitric oxide (NO) levels, citrulline levels, peroxidative damage, and differential modulation of antioxidant defense system. AV administration (seven weeks, 500 mg/kg b.w. daily) to CS inhaling mice led to modulation of CS induced pulmonary changes as revealed by lesser degree of histoarchitectural alterations, lesser mucin production, decreased NO levels, citrulline levels, peroxidative damage, and serum LDH activity. AV treatment to CS inhaling mice was associated with varying response to antioxidant defense system, however balf of CS + AV treated animals did not exhibit appreciable changes when compared with that of CS exposed animals. These observations suggest that AV has the potential to modulate CS induced changes in the pulmonary tissue which could have implications in management of CS associated pulmonary diseases, however, further investigations are required to explore its complete mechanism of action. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 999–1013, 2015.  相似文献   
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