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991.
目的:探讨基于第3代双源CT动态心肌灌注成像(CT-MPI)定量的正常心肌血流量(MBF)与负荷后心率增量的关系。方法:回顾性分析2016年10月至2019年11月于上海交通大学附属第六人民医院行动态CT-MPI及冠状动脉CTA(CCTA)检查的冠状动脉正常或冠状动脉轻微狭窄(定义为任一心外膜血管直径狭窄<25%)44...  相似文献   
992.
Pancreatic islet transplantation can replace functional insulin-secreting beta cells for patients with type 1 diabetes. More than 300 patients who have received islet transplantation have returned to a euglycemic condition without using insulin. Therefore, islet transplantation has gained public attention and interest. Unfortunately, shortages in organ donations, suboptional antirejection regimens, and difficulties in islet isolation limit clinical utilization of this therapy. Recently, successful islet transplantation has been reported using a centralized islet isolation facility. The advantage of this experience is that it avoids the high costs in building an isolation facility and maintaining an experienced technical team. However, a private airplane carrier was required for transporting islets back to the transplantation site in a remote hospital. The cost of this specialized transportation was still too high to be considered as a routine procedure. In this study, we report our experience using commercial carriers to deliver isolated human islets from an established isolation facility to a remote medical center.  相似文献   
993.
Recent improvements in isolated islet transplantation indicate that this therapy may ultimately prove applicable to patients with type I diabetes. An obstacle preventing widespread application of islet transplantation is an insufficient supply of cadaveric pancreata. Non-heart-beating donors (NHBDs) are generally not deemed suitable for whole-organ pancreas donation and could provide a significant source of pancreata for islet transplantation. Isolated pancreatic islets prepared from 10 NHBDs were compared with those procured from 10 brain-dead donors (BDDs). The success of the isolation for the two groups was analyzed for preparation purity, quality, and recovered islet mass. The function of NHBD and BDD islets was evaluated using in vitro and in vivo assays. On the basis of the results of this analysis, an NHBD isolated islet allograft was performed in a type I diabetic. The recovery of islets from NHBDs was comparable to that of control BDDs. In vitro assessment of NHBD islet function revealed function-equivalent BDD islets, and NHBD islets transplanted to non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice efficiently reversed diabetes. Transplantation of 446,320 islet equivalents (IEq) (8,500 IEq/kg of recipient body weight) from a single NHBD successfully reversed the diabetes of a type I diabetic recipient. Normally functioning pancreatic islets can be isolated successfully from NHBDs. A single donor transplant from an NHBD resulted in a state of stable insulin independence in a type I diabetic recipient. These results indicate that NHBDs may provide an as yet untapped source of pancreatic tissue for preparation of isolated islets for clinical transplantation.  相似文献   
994.
Objectives: The goal of this study was to evaluate the effects of middle ear packing agents (MEPA) on post-operative hearing improvement and complications after tympanoplasty in patients with adhesive otitis media (OM).

Materials and methods: Patients with adhesive OM who underwent tympanoplasty surgery were enrolled in the study between January 2012 and January 2015. A total of 205 patients who received canal wall-down tympanoplasty with ossicular chain reconstruction were randomized into one of the three groups with different MEPA. Group 1 (n?=?72) received MeroGel as the MEPA, Group 2 (n?=?64) cartilage, and Group 3 (n?=?69) both. Air conduction (AC) and bone conduction (BC) thresholds at 0.5, 1, 2, and 4?kHz were measured, and air-bone gaps (ABG) were analyzed before and after the surgery for each patient.

Results: Mean pre- and post-operative ABG was 30.9?dB and 17.6?dB in Group 1, 31.4?dB and 21.9?dB in Group 2, and 32.2?dB and 19.1?dB in Group 3. The ABG closure was 13.3?±?7.5 in Group 1, 9.5?±?5.9 in Group 2, and 13.1?±?9.3 in Group 3. The improvement of ABG after surgery was statistically significant in all three groups (p?p?Conclusions: Tympanoplasty using esterified hyaluronic acid (i.e. MeroGel) or cartilage as the MEPA resulted in improved hearing for patients with conductive hearing loss due to adhesive OM. Using MeroGel as the MEPA appeared to achieve a better post-operative outcome than using cartilage.  相似文献   
995.
目的 评估宁夏地区儿童头颅、胸部CT检查的辐射剂量水平,为不同年龄段儿童的CT辐射剂量优化提供基础。方法 采用分层整群抽样的方法,实地采集宁夏地区不同市、县、区不同规模医院1~2周内儿童(≤15岁)头颅、胸部CT的扫描参数、容积CT剂量指数(CTDIvol)及剂量长度乘积(DLP),计算患者有效剂量(E)值;并将CTDIvol、DLP的第75百分位数(P75)与其他国家推荐的DRL值进行比较;所有儿童分4个年龄组:<1岁、1~5岁、6~10岁、11~15岁。结果 走访调查39家医院,调查CT设备47台,采集头颅断层扫描1 134例,胸部平扫636例。头颅CTDIvol、DLP的P75分别为:<1岁:44.2 mGy、456.2 mGy·cm;1~5岁:57.2 mGy、659.6 mGy·cm;6~10岁:61.1 mGy、668.7 mGy·cm;11~15岁:63.6 mGy、849.3 mGy·cm。胸部CTDIvol、DLP的P75分别为:<1岁:5.0 mGy、89.2 mGy·cm;1~5岁:5.9 mGy、124.8 mGy·cm;6~10岁:6.0 mGy、167.9 mGy·cm;11~15岁:7.1 mGy、235.0 mGy·cm。结论 宁夏地区儿童胸部CT的辐射剂量与其他报道相近,但头颅CT的辐射剂量相对偏高,且各年龄段均存在偏高现象,尤以婴儿患者较著;应加强宁夏地区儿童头颅CT的辐射剂量优化与监管,增强儿科医生、放射科医生的剂量控制意识,提高对辐射相关风险的认识。  相似文献   
996.
目的确定我国民航飞行学员飞行训练的应激源。方法采用德尔菲法形成量表初步维度并在此基础上编制初测量表,从不同训练分院及国外训练归校的学员中采取分层随机取样;选取524名飞行学员进行测试,对所得数据进行分析形成正式问卷。对所获数据进行探索性因素分析和验证性因素分析,并分别检验量表的内部一致性系数、重测信度、内容效度与结构效度。结果训练环境、职业前景、飞行教员、座舱环境4个维度共解释了总变异的57.154%。量表总体的Cronbach’sα系数为0.830,各因子的Cronbach’sα系数为0.751~0.782,重测的相关系数均在0.806(P<0.01)以上。维度间的相关系数为0.134~0.438(P<0.05),各维度与总体的相关系数在0.617~0.748(P<0.01)。一阶4因素模型(GFI=0.929、IFI=0.989、TLI=0.986、CFI=0.989、RMSEA=0.013)拟合效果较好。结论民航飞行学员飞行训练应激源量表符合心理测量学标准,具有良好信效度,民航飞行学员飞行训练应激源主要来源于训练环境、职业前景、飞行教员、座舱环境。  相似文献   
997.
目的 探讨甲状腺乳头状癌(PTC)患者术后首次131I治疗后影响辐射剂量率降低的相关因素,并预估其住院隔离时间。方法 选取2015年5月至2018年11月于南方医科大学珠江医院住院并首次行131I治疗的PTC患者167例,其中男性43例、女性124例,年龄(37.14± 12.00)岁。将所有患者按治疗剂量分为高剂量组(63例)和低剂量组(104例),于治疗后24、48、72、96 h时测量距离患者1 m处的辐射剂量率,将治疗后患者体内滞留131I活度为400 MBq时的时间点定为出院时间。采用多重线性回归方法分析影响辐射剂量率降低的相关因素。组间比较采用两独立样本非参数检验或两独立样本t检验。结果 PTC患者首次行131I治疗后的辐射剂量率随时间推移迅速下降,高剂量组治疗后的24、48 h辐射剂量率[(70.62±34.45)、15.64 μSv/h]明显高于低剂量组[(11.27±5.13)、2.03 μSv/h],且差异均有统计学意义(t=-13.581、-7.952,均P <0.01)。81.0%(51/63)和90.5%(57/63)的高剂量组患者分别可在治疗48 h和72 h后出院,99%(103/104)的低剂量组患者可在治疗24 h后出院。多重线性回归分析显示,131I剂量和2 h摄碘率对高剂量组24 h辐射剂量率的影响有统计学意义(F=9.23,复相关系数R2=0.212,P<0.01),高剂量组24 h辐射剂量率与2 h摄碘率和131I剂量呈正相关;性别、24 h摄碘率和残甲法3对高剂量组48 h辐射剂量率的影响有统计学意义(F=34.45,复相关系数R2=0.622,P<0.01),48 h辐射剂量率与24 h摄碘率和残留甲状腺体积呈正相关,与性别呈负相关;131I剂量和24 h饮水量对低剂量组24 h辐射剂量率的影响有统计学意义(F=12.76,复相关系数R2=0.186 ,P<0.01),低剂量组24 h辐射剂量率与131I剂量呈正相关,与24 h饮水量呈负相关。结论 PTC术后患者首次131I治疗24 h后,影响其辐射剂量率降低的主要因素是服用131I的剂量,而48 h后的主要影响因素是24 h甲状腺摄碘率、残留甲状腺体积和性别。低剂量组和高剂量组平均住院时间分别为1 d和2 d左右。  相似文献   
998.
Myoclonus dystonia syndrome(MDS)is an inherited movement disorder,and most MDS-related mutations have so far been found in theε-sarcoglycan(SGCE)coding gene.By generating SGCE-knockout(KO)and human 237 C>T mutation knock-in(KI)mice,we showed here that both KO and KI mice exerted typical movement defects similar to those of MDS patients.SGCE promoted filopodia development in vitro and inhibited excitatory synapse formation both in vivo and in vitro.Loss of function of SGCE leading to excessive excitatory synapses that may ultimately contribute to MDS pathology.Indeed,using a zebrafish MDS model,we found that among 1700 screened chemical compounds,Vigabatrin was the most potent in readily reversing MDS symptoms of mouse disease models.Our study strengthens the notion that mutations of SGCE lead to MDS and most likely,SGCE functions to brake synaptogenesis in the CNS.  相似文献   
999.
目的总结与评价应用不同类型附着体的种植覆盖义齿的临床效果。方法对28例无牙颌患者分别采用种植体支持的磁附着体、杆卡式、套筒冠、球帽式覆盖义齿随访及效果进行对比评价。观察随访,定期拍摄X线片及口腔检查,观察种植体骨吸收和软组织状况,并对使用4种类型覆盖义齿的患者进行满意度调查和并发症分析。结果除1例磁附着体覆盖义齿患者发生3枚种植体脱落现象外,其余种植体均稳定。不同类型附着体种植覆盖义齿的骨吸收量、牙龈指数和满意度评价的差异均无统计学意义﹙P>0.05﹚;患者戴牙前后的义齿总体满意度、义齿固位及稳定情况、咀嚼效率、舒适度方面有明显的改善(P<0.05﹚。结论各类种植体支持的覆盖义齿稳定舒适,咀嚼功能增强,患者对满意度有较高的评价,提高了无牙颌患者的生存质量。  相似文献   
1000.
Increased hemichannel opening induced by oxygen glucose deprivation (OGD) was reported in the hippocampal pyramidal neuron. It was suggested that the pannexin1 hemichannel opening could mediate ionic flux dysregulation, anoxic depolarization, and energy-depleting efflux of glucose and ATP for ischemic neurons. However, the regulatory mechanisms of pannexin1 hemichannel opening have been poorly understood. Here we showed that excessive generation of nitric oxide (NO) during ischemia could induce the calcein leakage from neurons, which was markedly reduced by NO synthase inhibitor. The calcein leakage from neurons during OGD was also attenuated by the application of N-ethylmaleimide (NEM), an SH-alkylating agent, and dithiothreitol (DTT), a reducer of oxidized sulfhydryl groups. However, the soluble guanylyl cyclase (sGC) inhibitor had a minor effect on the calcein leakage during OGD. Furthermore, the elevated intracellular but not extracellular levels of glutathione could also inhibit the calcein leakage during OGD. Similar results were observed in metabolic inhibition (MI), which is another ischemic-like condition. Finally, immunocytochemical and immunoblotting analysis revealed that, after 1 hr of OGD stimulation, the distribution and expression of pannexin1 showed no significant difference compared with control. However, the pannexin1 mRNA expression was elevated after 1 hr of OGD and a sustained increase was maintained during reperfusion. These results implied that the reactive oxygen species (ROS), especially NO, might be involved in the enhanced pannexin1 hemichannel opening and that the S-nitrosylation but not the NO/cGMP pathway played a more important role in this event.  相似文献   
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