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71.
目的 探讨N-乙酰-5-羟色胺(N-acetylserotonin,NAS)对视网膜缺血-再灌注损伤(retina ischemia-reperfusion injury,RIRI)大鼠视网膜Fas、FasL蛋白表达的影响。方法 取健康成年Sprague Dawley大鼠54只,将大鼠随机分为正常组(6只)、RIRI组(24只)与NAS组(24只);采用高眼压法建立大鼠RIRI模型,依据造模后不同时间点将RIRI组与NAS组大鼠又分为6 h、12 h、24 h及72 h四个亚组。NAS组于造模前30 min腹腔注射NAS(5 mg·kg-1),RIRI组腹腔注射等剂量的生理盐水。通过HE染色在光学显微镜下观察各组大鼠视网膜形态学变化,并记录各组大鼠视网膜厚度及视网膜神经节细胞数,采用免疫组织化学染色法检测NAS对RIRI大鼠视网膜Fas、FasL蛋白表达的影响。结果 HE染色显示,正常组大鼠视网膜各层细胞分界清晰,形态正常,神经细胞排列整齐;RIRI组大鼠再灌注后6 h视网膜各层出现水肿,以神经节细胞层及内核层较显著,神经节细胞数较正常组减少;随后视网膜水肿进一步加重,神经节细胞继续减少;NAS组大鼠在再灌注后6 h、12 h、24 h 视网膜水肿程度较 RIRI组轻,NAS组在再灌注后72 h视网膜厚度较 RIRI组厚,NAS组各时间点神经节细胞数均较 RIRI组多,差异均有统计学意义(均为P<0.05)。免疫组织化学染色显示,正常组几乎未见 Fas+细胞。再灌注后6 h,RIRI组视网膜神经节细胞及内核层开始出现少量 Fas+细胞;再灌注后12 h,RIRI组视网膜 Fas+细胞表达逐渐增多;再灌注后24 h视网膜Fas+细胞数达到高峰,棕色阳性染色细胞分布在视网膜神经节细胞层、内丛状层、内核层及神经纤维层;再灌注后 72 h 视网膜 Fas+细胞较再灌注后 24 h 减少。NAS组在再灌注后6 h、12 h、24 h、72 h 视网膜 Fas+细胞数均较 RIRI组各时间点减少,再灌注后24 h,Fas+细胞数达较高水平,随后下降,差异均有统计学意义(均为P<0.05)。正常组视网膜可见 FasL 全层低表达。RIRI组再灌注后 6 h,视网膜神经节细胞层和神经纤维层存在少量 FasL+细胞;再灌注后12 h FasL蛋白表达逐渐增多;再灌注后24 h FasL+细胞数达高峰,可见深棕色的细胞膜及细胞质染色细胞分布在视网膜神经节细胞层、内丛状层、内核层及神经纤维层;再灌注后72 h FasL蛋白的阳性表达逐渐减少。NAS组再灌注后6 h、12 h、24 h、72 h 视网膜FasL+细胞数均少于 RIRI组各时间点阳性细胞数,差异均有统计学意义(均为P<0.05)。结论 NAS可通过抑制RIRI大鼠视网膜细胞Fas、FasL蛋白的表达,减轻缺血再灌注对大鼠视网膜细胞造成的损伤。  相似文献   
72.
A multitude of athletic injuries occur when the various tissues that make up the human body experience stresses and strains that exceed their material strength. The precise amount of stress and strain that any given tissue can withstand is determined by the mechanical properties and resultant strength of that particular tissue. These mechanical properties are directly determined by an individual’s physiology and acute regulation of these properties. A number of theoretical frameworks for athletic injury occurrence have been proposed, however, a detailed conceptual framework for injury aetiology that considers the interplay between the physiological and mechanical factors and outlines the causal pathways to tissue damage and injury is needed. This will guide injury research towards a more thorough investigation of causal mechanisms and understanding of risk factors. Further, it is important to take into account the considerable differences in loading patterns which can result in varying injury outcomes such as acute stress-related, strain-related, or overuse injury. Within this article a simplified conceptual model of athletic injury is proposed along with a detailed, evidence-informed, conceptual framework for athletic injury aetiology that focuses on stress-related, strain-related, and overuse injury.  相似文献   
73.
74.
Objective: The objective of this study was to gain greater insight into individuals’ quality of life (QOL) definitions, appraisals, and adaptations following spinal cord injury (SCI).

Design: A mixed-methods design, applying the Schwartz and Sprangers response shift (RS) model. RS is a cognitive process wherein, in response to a change in health status, individuals change internal standards, values, or conceptualization of QOL

Setting: Community-dwelling participants who receive medical treatment at a major Midwestern medical system and nearby Veterans’ Affairs hospital.

Participants: A purposive sample of participants with SCI (N?=?40) completed semi-structured interviews and accompanying quantitative measures.

Interventions: Not applicable.

Outcome Measures: Qualitative data were analyzed using content analysis to identify themes. Analysis of variance were performed to detect differences based on themes and QOL, well-being, and demographic and injury characteristics.

Results: Four RS themes were identified, capturing the range of participant perceptions of QOL. The themes ranged from complete RS, indicating active engagement in maintaining QOL, to awareness and comparisons redefining QOL, to a relative lack of RS. Average QOL ratings differed as a function of response shift themes. PROMIS Global Health, Anxiety, and Depression also differed as a function of RS themes.

Conclusion: The RS model contextualizes differences in QOL definitions, appraisals, and adaptations in a way standardized QOL measures alone do not.  相似文献   

75.
IntroductionThis article deals with the occurrence of health problems due to gunshot wounds to the face among military police officers, in the metropolitan region of Rio de Janeiro, who were submitted to surgery at the Oral and Maxillofacial Surgery and Traumatology Clinic of Hospital Central da Polícia Militar.ObjectiveTo identify the profile of patients submitted to surgery as a result of gunshot wounds, the anatomical distribution of maxillofacial fractures, the identified sequelae and complications, the health specialties involved in the rehabilitation of these patients, and to discuss the social, emotional and work performance-related effects of work among these subjects.MethodsA retrospective epidemiological study was carried out based on secondary data from military police officers who were submitted to surgery at Hospital Central da Polícia Militar due to gunshot wounds from June 2003 to December 2017.ResultsDuring the study period, 778 surgeries were performed in the operating room by the Oral and Maxillofacial Surgery and Traumatology service at Hospital Central da Polícia Militar, 186 of which were due to gunshot wounds (23.9%). All patients were males and the mean age 34.7 years. Bone segment loss was the most common sequela. Facial esthetic impairment and reports of insomnia were the most often identified late consequences of impact on health and social life. Regarding the occupational impacts of the sustained injury, the mean time away from work due to medical leave for the treatment of maxillofacial injuries was 11.7 months.ConclusionThe treatment of gunshot wounds patients with facial injuries requires multiple surgical interventions and their rehabilitation requires the involvement of different health specialties. Further studies are needed to qualitatively analyze the impact of this type of facial trauma on the patients' lives and their social consequences.  相似文献   
76.

Background Context

Long-term follow-up of patient-reported outcome measures (PROM) is essential in both modern spinal care and research. Lack of time and staff are commonly reported barriers to implementing long-term follow-up of PROM. Automated and digital follow-up systems for PROM collection are seeing widespread use, yet their validity and comparative effectiveness have never been evaluated.

Purpose

The present study aimed to assess the validity of digital follow-up systems in comparison with the conventional paper-based follow-up (PB-FU).

Study Design

This is a retrospective analysis of prospectively collected double follow-up data.

Patient Sample

Patients who underwent lumbar spinal fusion for spondylolisthesis or degenerative disc disease between 2013 and 2016 were included in the study.

Outcome Measures

The study determined the Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS) for back and leg pain severity at baseline, 6 weeks, 12 months, and 24 months.

Materials and Methods

After lumbar spinal fusion surgery, a double follow-up of PROM was carried out by conventional PB-FU during clinical visits, while simultaneously completing an automatically dispatched digital follow-up questionnaire. As the primary end point, we assessed the intraindividual discrepancy in PROM between PB-FU and automated digital follow-up (AD-FU).

Results

Forty patients completed all parts of the dual follow-up trajectory and were analyzed. We detected no discrepancy in ODI or NRS for back and leg pain severity at any of the baseline, 6-week, 12-month, or 24 month follow-ups (all p>.05). This was confirmed in a sensitivity analysis.

Conclusions

In an analysis of dual paper-based and digital follow-up after lumbar fusion surgery, patients report highly similar values using either method of follow-up. It appears that AD-FU without incentives produces lower response rates. To reassess the validity of these systems for data collection in spinal patient care, a prospective validation with higher statistical power is warranted.  相似文献   
77.
Amyotrophic lateral sclerosis is a fatal neurodegenerative disorder characterized by upper and lower motor neuron degeneration, which leads to progressive paralysis of skeletal muscles and, ultimately, respiratory failure between 2–5 years after symptom onset. Unfortunately, currently accepted treatments for amyotrophic lateral sclerosis are extremely scarce and only provide modest benefit. As a consequence, a great effort is being done by the scientific community in order to achieve a better understanding of the different molecular and cellular processes that influence the progression and/or outcome of this neuropathological condition and, therefore, unravel new potential targets for therapeutic intervention. Interestingly, a growing number of experimental evidences have recently shown that, besides its well-known physiological roles in the developing and adult central nervous system, the Wnt family of proteins is involved in different neuropathologica conditions, including amyotrophic lateral sclerosis. These proteins are able to modulate, at least, three different signaling pathways, usually known as canonical(β-catenin dependent) and non-canonical(β-catenin independent) signaling pathways. In the present review, we aim to provide a general overview of the current knowledge that supports the relationship between the Wnt family of proteins and its associated signaling pathways and amyotrophic lateral sclerosis pathology, as well as their possible mechanisms of action. Altogether, the currently available knowledge suggests that Wnt signaling modulation might be a promising therapeutic approach to ameliorate the histopathological and functional deficits associated to amyotrophic lateral sclerosis, and thus improve the progression and outcome of this neuropathology.  相似文献   
78.
正枕骨、寰椎和枢椎共同构成了枕颈部活动的结构功能单位,即枕颈交界区~([1-2])。炎症、创伤、肿瘤及畸形等因素会导致枕颈交界区失稳,从而引起颈脊髓或神经根的损伤、麻痹及难以忍受的疼痛,甚至危及生命~([3-4])。后路内固定融合技术是治疗枕颈部失稳的重要手段,目前常用术式为枕骨螺钉技术,该技术较钢丝固定技术有更好的生物力学稳定  相似文献   
79.
Inflammation plays a critical role in the development of ventilator-induced lung injury (VILI). Endoplasmic reticulum (ER) stress is associated with a variety of diseases through the modulation of inflammatory responses. However, little is known about how ER stress is implicated in VILI. In this study, murine mechanical ventilation models were constructed. Total protein and inflammatory cytokines were measured in bronchoalveolar lavage fluid (BALF), and lung tissue injury was assessed by histology. Our data revealed that mice subjected to high tidal ventilation (TV) for 4 h showed more severe pulmonary edema and inflammation than those of mice with spontaneous breathing and low TV-treatment. In addition, the high TV-treated animals upregulated the ER stress markers GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB expression at both the mRNA and protein levels in lung tissue. Administration of thapsigargin exacerbated the histological changes, inflammation and expression of GRP78 and CHOP after high TV, but treatment with ER stress and IRE1α kinase inhibitors attenuated the pathological damage and downregulated the high expression of GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB, suggesting that ER stress is involved in VILI though the IRE1α/TRAF2/NF-κB signaling pathway in mice.  相似文献   
80.
ObjectivesThis study aimed to validate the skin temperature on sacral region and vascular attributes as early warning signs of pressure injury.MethodsTotally 415 patients admitted to the adult intensive care unit from August 2018 to April 2019 were prospectively screened. Daily blood pressure and blood glucose affecting vascular attributes and the relative skin temperature of sacral region were measured for 10 consecutive days. Collect the changes of these indicators during the occurrence of pressure injury. The optimal cut-off values of indicators were determined by X-tile analysis. The risk ratios of indicators associated with pressure injury were compared using the Cox proportional hazards regression model.ResultsThere were no obvious interactions among blood pressure, blood glucose and relative skin temperature (P > 0.05). The optimal cutoff value for above indicators was 63.5 mmHg, 9.9 mmol/L and −0.1 °C, respectively. The incidence of pressure injury peaked on the 4th and 5th day after hospitalization when categorizing the patients into low- and high-risk groups according to the cutoff values (P < 0.05). Based on relative skin temperature, patients in the high-risk group were more likely to develop pressure injury (hazard ratio = 6.36, 95% confidence interval = 3.91, 10.36), when compared to the other two indicators of blood pressure and blood glucose.ConclusionStringent skin temperature and vascular attributes measurements were necessary for preventing pressure injury. Nursing measures should be taken according to warning sings to reduce the incidence of pressure injury.  相似文献   
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