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21.
角膜移植为治疗角膜盲的主要手段,而角膜移植排斥则是决定角膜植片存活时间和病人术后视力的关键。角膜得益于其特殊的眼前节“免疫赦免”状态,使得角膜移植能够在众多器官移植中享有极低的排斥率,然而排斥反应发生的风险依然存在。当机体处于遗传物质异常的特殊状态时,宿主将通过宏观调控“免疫赦免”状态对植片的保护作用或受体对移植物排异产生的有害作用,延迟或促进角膜移植排斥反应的发生,进而影响移植物的存活时间和透明度。该文综述与角膜移植排斥相关的多种全身性遗传疾病,总结全身性遗传疾病对角膜移植排斥的影响,浅析其发生的病理生理学机制以及诊疗的特殊性。 相似文献
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《Research in social & administrative pharmacy》2022,18(9):3694-3698
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area. 相似文献
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《Injury》2023,54(6):1702-1710
IntroductionPatients with cirrhosis are at higher risk for morbidity after injury. Acetabular fractures represent a highly morbid injury pattern. Few studies have specifically examined an effect of cirrhosis on risk of complications after acetabular fracture. We hypothesized that cirrhosis is independently associated with increased risk of inpatient complications following operative treatment of acetabular fractures.MethodsAdults patients with acetabular fracture who underwent operative treatment were identified from Trauma Quality Improvement Program data from 2015 to 2019. Patients with and without cirrhosis were matched on a propensity score predicting cirrhotic status and inpatient complications based on patient, injury, and treatment characteristics. The primary outcome was overall complication rate. Secondary outcomes included serious adverse event rate, overall infection rate, and mortality.ResultsAfter propensity score matching, 137 cirrhosis+ and 274 cirrhosis- remained. No significant differences existed in observed characteristics after matching. Compared to cirrhosis- patients, cirrhosis+ patients experienced 43.4% (83.9 vs 40.5%, p < 0.001) greater absolute risk difference of any inpatient complication, 29.9% (51.8 vs 21.9%, p < 0.001) greater absolute risk difference of serious adverse events, 28.5% (41.6 vs 13.1%, p < 0.001) greater absolute risk difference of any infection, and 2.9% (2.9% vs 0.0%, p = 0.02) greater absolute risk difference of inpatient mortality.ConclusionCirrhosis is associated with higher rates of inpatient complications, serious adverse events, infection, and mortality among patients undergoing operative repair of acetabular fracture.Level of EvidencePrognostic Level III. 相似文献
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《Vaccine》2022,40(7):1001-1009
Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases. 相似文献
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《Gait & posture》2022
BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η2 = 0.114) and liftoff (p = 0.122, η2 = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η2 = 0.648) and liftoff (p < 0.001, η2 = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η2 = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion. 相似文献
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Adjuvant irradiation is the standard treatment after breast conservative surgery. Normofractionated regimen with an overall treatment time of 5 to 6 weeks is often considered as a limiting factor for irradiation compliance. In order to answer this issue, moderate and more recently extreme hypofractionated protocols appeared. We report here oncological outcomes and toxicity of hypofractionated breast irradiation. After defining the frame of moderate and extreme hypofractionated breast irradiations based on overall treatment time, patient selection criteria were listed. According to their levels of proof, the results of moderate and extreme hypofractionated breast irradiation were analysed. Overall treatment time for moderate hypofractionated breast irradiation ranged from 3 to 4 weeks, while for extreme hypofractionated breast irradiation, it was less than 1 week. For moderate hypofractionated breast irradiation, whole breast irradiation was currently performed with or without lymph node irradiation. Moderate hypofractionated breast irradiation has proven to be as safe and as efficient as normofractionated breast irradiation with level IA evidence. For extreme hypofractionated breast irradiation, phase III randomized trials confirmed that accelerated partial breast irradiation was non-inferior in terms of local control compared to normofractionated whole breast irradiation (with external beam radiation therapy and multicatheter brachytherapy), with similar acute and late toxicity. While the use of intraoperative breast irradiation remains under debate, new very accelerated partial breast irradiation (overall treatment time not exceeding 2 days) protocols emerged with encouraging results. Accelerated partial breast irradiation is warranted for extreme hypofractionated breast irradiation and is indicated for low-risk breast cancers. Moderate and extreme hypofractionated breast irradiation regimens are validated and can be routinely proposed according to patient selection criteria. 相似文献