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Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T2-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T2-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T2-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T2 relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T2 was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T2 relaxation time was derived (R2 = 0.98): T2 (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T2-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T2-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.  相似文献   
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AimThe aim of this study was to develop a Turkish version of the Pressure Ulcer Knowledge Assessment Tool 2.0 (PUKAT 2.0) and determine its validity and reliability.Materials and MethodsThis was a cross-cultural adaptation and validation study. The study sample included a total of 451 participants (232 nurses and 219 nursing students). The validity of the Turkish version of the PUKAT 2.0 was evaluated with linguistic validity, content validity, item validity (item difficulty, discriminating index), and construct validity (known-groups technique) analyses. The reliability of the tool was evaluated by conducting a test–retest analysis.ResultsContent validity index (CVI) for the items (Item-CVI) ranged from 0.83 to 1.00 and the CVI for the scale (Scale-CVI) was 0.95. The difficulty index for 21 items ranged from 0.10 to 0.63. Four items were found to be too difficult. Item discriminating index values ranged from 0.00 to 0.61. The overall intraclass correlation coefficient (ICC) was found to be 0.80.ConclusionThe Turkish version of the Pressure Injury Knowledge Assessment Tool 2.0 (PIKAT 2.0-Tr) is supported by acceptable psychometric properties and can be used to evaluate the knowledge of nurses and nursing students in Turkey about the prevention of PI.  相似文献   
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目的:通过给小鼠腹腔注射右旋糖酐铁,建立小鼠铁过载干眼模型并初步探索其可能的机制。

方法:将40只雄性C57BL/6小鼠(取右眼为实验眼)用随机数字表法将小鼠分为4组:对照组10只,每次腹腔注射生理盐水0.2mL; 低剂量组、中剂量组、高剂量组各10只为模型组,每次分别腹腔注射浓度为12.5、25、50mg/mL的右旋糖酐铁溶液0.2mL。每3d注射1次,共注射28d。注药后第7、14、28d观察各组小鼠眼表炎症指数、角膜荧光素染色、泪膜破裂时间(BUT)及泪液分泌量(SⅠt),评估干眼及眼表炎症程度。28d后处死小鼠,取角膜、结膜及泪腺组织,进行HE染色、普鲁士蓝染色以及组织铁检测,评估小鼠炎症反应及铁过载情况; 采用酶联免疫吸附试验(ELISA)检测炎症因子白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、基质金属蛋白酶-9(MMP-9)的表达情况。

结果:与对照组相比,模型组小鼠出现一系列干眼症状,小鼠眼表炎症指数增高,角膜荧光素染色评分增加,BUT缩短,泪液分泌量减少(均P<0.05); 模型组小鼠角膜、结膜及泪腺组织均受到不同程度的损伤,各组织眼表铁沉积情况较对照组加重,组织铁含量明显增加(均P<0.01); 模型组小鼠角膜、结膜及泪腺组织中炎症因子(IL-1β、TNF-α、MMP-9)的含量均高于对照组(均P<0.01),随着右旋糖酐铁注药时间及浓度增加,小鼠干眼及眼表炎症程度逐渐加重。

结论:腹腔注射右旋糖酐铁可成功建立小鼠铁过载干眼模型,其机制可能与铁过载加重眼表炎症反应有关。  相似文献   

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ObjectivesTo compare time to incidence, extent of incidence and severity of heel pressure injury with a heel off-loading boot (intervention) or pillows (control).Research methodology/designMulti-centre, single-blinded randomised controlled trial of 394 critically ill patients. Patients were randomised to the intervention or control for heel offloading.SettingThree hospital intensive care units; two in greater Sydney, Australia and one in regional New South Wales, Australia.Main outcome measuresTime to intensive care unit-acquired pressure injury in heels of patients without pre-existing heel pressure injury within 28 days from intensive care unit admission. Secondary outcomes: incidence of heel pressure injury within 28 days of intensive care unit admission; severity of intensive care unit-acquired heel pressure injuries; occurrence of plantar contractures (a change in ankle dorsiflexion of 5° or greater) within 28 days of admission.ResultsWithin 28 days of admission, one pressure injury was recorded in the intervention group and 11 in the control group. Hazard of pressure injury incidence within 28 days of admission was significantly lower (p = 0.0239) in heels assigned to the intervention (hazard ratio 0.0896 [95% CI 0.0110, 0.727]). Odds of pressure injury incidence within 28 days of admission were significantly lower (p = 0.0261) in the intervention group (odds ratio 0.0883 [95% CI 0.0104, 0.749]). The pressure injury recorded in the intervention group was superficial (stage 1) whereas those recorded in the control group were more severe (stage 2 to 4).ConclusionThe heel-offloading boot used in this study significantly reduced heel pressure injury occurrence compared with heel offloading using pillows.  相似文献   
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《Indian heart journal》2022,74(4):302-306
BackgroundThe alarming rise in prevalence of hypertension warrants psychosocial methods supplementing pharmacotherapy for better management and prevention of cardiac emergencies. The objective of the study was to assess the differential impact of the form and frequency of knowledge intervention on management of primary hypertension.Materials and methodThe study was conducted on 256 hypertensive patients recruited through purposive sampling at health centers in Hyderabad, India. Pretest post-test control group quasi-experimental design was adopted for the study. There were two forms of the knowledge intervention, namely ‘Direct Interaction’ and ‘Audio-Visual’. Each form was presented in two frequencies namely ‘single exposure’ and ‘double exposure’. The four groups were labelled as Direct Intervention Single (DIS), Direct Intervention Double (DID), Audio-Visual Single (AVS) and Audio-Visual Double (AVD). Adherence and management of hypertension were assessed at baseline and six weeks post experiment. Analysis of Covariance (ANCOVA) was applied using IBM SPSS Statistics version 20.ResultsANCOVA followed by Bonferroni Multiple Group Comparison Test revealed significant differences between the four intervention groups and control group on adherence (p< .001). In case of hypertension management significant differences were observed between Control group and DIS, DID (p < .001), Control and AVS (p < .01). Control group did not differ from AVD.ConclusionThere was a positive impact of Knowledge Intervention on adherence and management of hypertension. Double exposure in audio visual form was counterproductive in hypertension management.  相似文献   
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总结1例直肠癌患者术后继发腹壁多处坏死性软组织感染的护理经验。护理要点:感染性休克的早期识别和有效控制;坏死性软组织感染的识别及护理,控制全身性感染再次发生;分阶段落实个体化镇痛,改善疼痛症状;分阶段动态落实营养支持方案;实施全程心理干预。经过122 d的精心护理,8处伤口全部愈合,患者恢复良好。  相似文献   
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目的探讨微创手术和开腹手术治疗胆道结石患者的临床疗效及对胆道压力和胃肠道功能的影响,分析胆道压力与胃肠功能的相互关系。 方法回顾性分析2016年1月至2018年1月收治的124例胆道结石患者。开腹组60例患者采用开腹手术治疗,微创组64例患者采用腹腔镜下胆道镜内镜联合钬激光碎石术治疗。采用SPSS18.00统计软件分析,术中术后指标、炎性因子检测、术后胆道压测定和胃肠动力指标检测,以均数( ±s)形式录入,采用独立t检验;净石率、术后并发症比较采用χ2检验;胆道压力与胃肠动力指标相关性分析采用Spearman相关分析,以P<0.05表示差异有统计学意义。 结果微创组手术时间、住院天数、住院费用、净石率、并发症率均优于开腹组(P<0.05);微创组术后3 d、 5 d血清IL-6、 IL-8、 TNF-α浓度、 MTL、 CCK、 VIP水平和胆道压力和均显著低于开腹组(P<0.05);患者术后胆道压力与胃肠动力指标MTL、 CCK程负相关(r=-0.632, -0.678; P均<0.05);VIP水平与胆道压力程正相关(r=0.712; P<0.05)。 结论腹腔镜下胆道镜内镜联合钬激光碎石术治疗胆道结石临床效果明显,术后机体炎症反、胆道压力、胃肠动力指标更优,且胆道压力与胃肠动力指标具有一定相关性。  相似文献   
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