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81.
82.
PurposeTo investigated the effect of vibratory stimulus on masseter muscles during oral fine motor biting tasks.MethodsSixteen healthy individuals (age: 24.5 ± 2.4 years) participated in experiment I during which the participants were asked to “hold and split” half a roasted peanut placed on a force transducer with their front teeth. The participant performed ten series with ten trials of the “hold and split” behavioral task while vibratory stimulus was applied on the masseter muscle every alternate series. Further, fourteen participants participated (age: 25.2 ± 4.8 years) in experiment II during which they performed a series each of the behavioral task at baseline, an adjusted baseline without and with vibration as well as with and without visual feedback. Hold and split forces along with the variability of hold force and duration and force rate during the split were measured.ResultsThe results of the study showed an increase in the magnitude of the hold force (P = 0.002), force rate during the split (P < 0.001) and a significant decrease in the duration of split (P < 0.001) due to the vibratory stimulus. However, there was no significant effect of the vibratory stimulus on the variability of hold forces (P = 0.879) or mean split force (P = 0.683) during the “hold and split” behavioral task. The results of experiment II also showed an increase in hold force due to the vibratory stimulus (P < 0.001).ConclusionsVibratory stimulus to the masseter muscles impairs the oral force control during a standardized biting task and provide further insight into the sensorimotor regulation of the masticatory system.  相似文献   
83.
目的探究面肌痉挛患者微血管减压术(MVD)中异常肌反应(AMR)的变化特点与术后疗效的关系。方法回顾性分析73例MVD术中采用AMR全程定量化监测患者的AMR变化特点,减压操作前AMR阈值较基础阈值升高≥1倍为A1组、1倍为A2组,手术结束时AMR完全消失为B1组、未消失为B2组,B2组中AMR阈值较基础阈值升高≥1倍为B2a组、1倍为B2b组,对各组的术后疗效进行对比分析。结果 A1组21例中,19例立即治愈,1例延迟治愈,1例未愈; A2组52例中,35例立即治愈,9例延迟治愈,8例未愈。A1组较A2组疗效好(P=0. 046)。B1组50例中,42例立即治愈,5例延迟治愈,3例未愈; B2组23例中,12例立即治愈,5例延迟治愈,6例未愈。B1组较B2组疗效好(P=0. 003)。B2 a组的治愈比例较B2 b组高(分别为14/16、3/7),差异有统计学意义(P=0. 045)。结论 AMR在术中的变化特点对术者有重要参考意义,AMR在减压前升高、在手术结束时完全消失、未消失但升高较基础阈值≥1倍者术后疗效相对较好。  相似文献   
84.
85.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
86.
87.
Cutaneous leiomyomas are rare benign smooth‐muscle tumors. These lesions are distinguished based on their cell of origin and are subclassified as pilar leiomyoma, angioleiomyoma, and genital‐type leiomyoma. Nipple leiomyoma is the least common genital‐type leiomyoma, arising from the dartoic muscle cell of the nipple. Histologic examination of the lesion is necessary for definitive diagnosis, and these uncommon tumors can pose a diagnostic challenge. We describe herein a series of six nipple leiomyomas with a spectrum of histologic appearances.  相似文献   
88.
Introduction: This study explores the reliability and responsiveness of neuromuscular ultrasound in amyotrophic lateral sclerosis (ALS). Methods: Investigations were conducted with 10 healthy controls, 10 patients with ALS (single point in time), and 10 different patients with ALS (followed over 6 months; 4 completed follow-up). Ultrasound was used to measure the thickness of the geniohyoid, bilateral biceps/brachialis, bilateral tibialis anterior, and bilateral hemidiaphragms (at inspiration and expiration). Interrater and intrarater reliability and change in muscle thickness over 6 months were measured. Results: Interrater correlation coefficients ranged between 0.80 and 0.99 in healthy controls and between 0.78 and 0.97 in patients with ALS. Intrarater correlation coefficients ranged between 0.83 and 0.98 in healthy controls. The mean percentage decline in muscle thickness over 6 months was 20.25%. Discussion: Muscle ultrasound appears to be a reliable technique for measuring important muscles in patients with ALS. Larger studies with age-matched controls should be conducted to assess further the responsiveness of this biomarker in ALS. Muscle Nerve 59 :181–186, 2019  相似文献   
89.
目的 :分析退行性脊柱侧凸(adult degenerative scoliosis,ADS)患者椎旁肌(多裂肌、竖脊肌)MRI影像退变程度与脊柱-骨盆参数之间的关系,为ADS患者矢状位失平衡评估提供新的线索。方法:回顾性分析在我院就诊的女性ADS患者52例,年龄55~65岁,收集患者人口统计学资料,分别测量患者腰椎MRI上L1~S1椎间盘层面椎旁肌(多裂肌、竖脊肌)横截面积(cross-sectional area,CSA)、脂肪化比例(fat saturation fraction,FSF),并在患者脊柱全长X线片上测量冠状位和矢状位的影像学参数,包括冠状位Cobb角、矢状位垂直偏距(sagittal vertical axis,SVA)、胸椎后凸角(thoracic kyphosis,TK)、腰椎前凸角(lumbar lordosis,LL)、骨盆倾斜角(pelvic tilt,PT)、骨盆入射角(pelvic incidence,PI)、骶骨倾斜角(sacral slope,SS)、PI-LL,对椎旁肌L1~S1各层面FSF行单因素方差分析并进行LSD事后多重比较,利用Pearson相关分析比较椎旁肌退变程度和脊柱-骨盆参数之间的关系。结果:L1~S1各层面FSF有显著性差异(P0.01),L5/S1层面椎旁肌FSF明显大于其他层面(P0.05)。冠状位Cobb角与L1/2、L2/3、L3/4、L4/5椎间盘层面CSA呈负相关(r=-0.358、-0.367、-0.329、-0.283,P0.05)。椎旁肌FSF与PT在L1~S1各层面呈正相关(r=0.487、0.394、0.354、0.356、0.355,P0.05),而与SS呈负相关(r=-0.494、-0.440、-0.373、-0.301、-0.300,P0.05)。椎旁肌FSF与LL在L1/2、L2/3层面呈负相关(r=-0.398、-0.328,P0.05)。椎旁肌总体FSF(TFSF)与PT呈正相关(r=0.395,P0.01),与LL呈负相关(r=-0.345,P0.05)。L1~S1各层面椎旁肌CSA、FSF与SVA、PI、TK的Pearson相关分析结果无统计学意义(P0.05)。BMI与L1~S1各层面椎旁肌CSA呈正相关(P0.05),而与椎旁肌各层面FSF的Pearson相关分析结果无统计学意义(P0.05)。结论:在ADS患者中,椎旁肌FSF与PT有明显的正相关性,提示椎旁肌的退变可能参与了脊柱退变和代偿机制的过程,椎旁肌FSF可能反映了ADS患者矢状位失平衡的严重程度。  相似文献   
90.
Atherosclerosis has long been known as an inflammatory disease. However, whether targeting inflammation improves outcomes was unproven until the recent results of CANTOS (Canakinumab Anti-Inflammatory Thrombosis Outcomes Study). In this review, we reflect on why it has taken a long time to prove the inflammatory hypothesis of atherosclerosis and derive important lessons for the future. In particular, we discuss the off-target immune-modulatory effects of approved cardiovascular therapies, review the attempted anti-inflammatory therapies including the recently published CIRT (Cardiovascular Inflammation Reduction Trial), and discuss the likely reasons for their failures. We further build on CANTOS to review the immune-modulatory therapies for atherosclerosis currently in trials, and discuss the likelihood of their added value as well as the potential hazard associated with their use. We finally argue for a critical approach to the use of animal models, coupled with the use of humans as model organisms to accelerate the identification of the most appropriate targets.  相似文献   
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