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31.
目的 探讨小儿弯刀综合征的诊断、外科治疗方法及治疗后的近、中期结果。方法 回顾性分析2010年1月到2017年12月手术治疗的14例弯刀综合征的临床资料。其中,男7例,女7例;年龄(18.23±28.55)个月,范围在23 d至9岁。合并其他心血管畸形10例,中位心8例,右肺发育不良7例,有侧支循环8例,合并肺动脉高压10例。用SPSS 16.0软件的寿命表(Life Table)做出本组患儿术后生存曲线,评估其近、中期生存状况。结果 9例异常肺静脉(scimitar vein,SV)从下腔静脉切下,端-侧吻合于左心房;SV分成2支2例,1例采用2支SV连同部分下腔静脉壁切下,另1例2支SV从下腔静脉从根部切下侧-侧吻合形成单根SV,均吻合于左心房;SV离左心房距离过大3例,2例将SV吻合在右心房右侧壁,再重建心房间隔,1例SV与自体心包卷管道连接再吻合于左心房。其他心血管畸形同期手术矫治。8例有侧支循环,3例心导管检查时被封堵,5例手术时切断缝合。本组14例手术死亡2例(14.29%),另有1例于术后1年2个月因肺炎、呼吸衰竭死亡。本组术后1、3、5年累积生存率分别为86%、73%和73%。术后出院时有1例移植的SV开口狭窄,血流速度为1.9 m/s;有3例随访期间发现移植SV狭窄,血流速度超过1.6 m/s。结论 弯刀综合征可合并其他心血管畸形、中位心、右肺发育不良等。一般将SV与左心房吻合;SV离左心房距离大或多条SV时,可采用个性化办法将SV吻合于左心房。侧支循环心导管检查时可封堵,或术中切断缝合。  相似文献   
32.
Background: Betel quid chewing is more common among the older generation in rural areas of Malaysia. Oral cancer in Asia has been associated with the habit of chewing betel quid and areca nut. Objective:  This study aims to investigate the cytotoxic effects of betel quid and areca nut extracts on the fibroblast (L929), mouth-ordinary-epithelium 1 (MOE1) and oral squamous cell carcinoma (HSC-2) cell lines. Methods: L929, MOE1 and HSC-2 cells were treated with 0.1, 0.2 and 0.4 g/ml of betel quid and areca nut extracts for 24, 48 and 72 h. MTT assay was performed to assess the cell viability. Results: Both extracts, regardless of concentration, significantly reduced the cell viability of L929 compared with the control (P<0.05). Cell viability of MOE1 was significantly enhanced by all betel quid concentrations compared with the control (P<0.05). By contrast, 0.4 g/ml of areca nut extract significantly reduced the cell viability of MOE1 at 48 and 72 h of incubation. Cell viability of HSC-2 was significantly lowered by all areca nut extracts, but 0.4 g/ml of betel quid significantly increased the cell viability of HSC-2 (P<0.05). Conclusion: Areca nut extract is cytotoxic to L929 and HSC-2, whereas the lower concentrations of areca nut extract significantly increased the cell viability of MOE1 compared to the higher concentration and control group. Although betel quid extract is cytotoxic to L929, the same effect is not observed in MOE1 and HSC-2 cell lines. Further investigations are needed to clarify the mechanism of action.  相似文献   
33.
Background: Breast cancer is a multifactorial disease that affects women worldwide. Its progression is likely to be executed by oxidative stress wherein elevated levels of reactive oxygen and nitrogen species drive several breast cancer pathologies. Spider venom contains various pharmacological peptides which exhibit selective activity to abnormal expression of ion channels on cancer cell surface which can confer potent anti-cancer activities against this disease. Methods: Venom was extracted from a Philippine tarantula by electrostimulation and fractionated by reverse phase-high performance liquid chromatography (RP-HPLC). Venom fractions were collected and used for in vitro analyses such as cellular toxicity, morphological assessment, and oxidative stress levels. Results: The fractionation of crude spider venom generated several peaks which were predominantly detected spectrophotometrically and colorimetrically as peptides. Treatment of MCF-7 cell line of selected spider venom peptides induced production of several endogenous radicals such as hydroxyl radicals (•OH), nitric oxide radicals (•NO), superoxide anion radicals (•O2−) and lipid peroxides via malondialdehyde (MDA) reaction, which is comparable with the scavenging effects afforded by 400 µg/mL vitamin E and L-cysteine (p<0.05). Concomitantly, the free radicals produced decrease the mitochondrial membrane potential and metabolic activity as detected by rhodamine 123 and tetrazolium dye respectively (p>0.05). This is manifested by cytotoxicity in MCF-7 cells as seen by increase in membrane blebbing, cellular detachment, caspase activity and nuclear fragmentation. Conclusion: These data suggest that the Philippine tarantula venom contains peptide constituents exhibiting pro-oxidative and nitrosative-dependent cytotoxic activities against MCF-7 cells and can indicate mechanistic insights to further explore its potential application as prooxidants in cancer therapy.  相似文献   
34.
放疗记录与验证系统(RVS)是一套用于防止医用电子加速器等放疗设备治疗参数设置错误,并且记录所有放疗阶段执行参数的医用计算机软件控制系统。为确保患者的治疗安全,必须对记录与验证系统采取必要的质量控制措施。本指南内容涉及:RVS安装和参数设定过程中的质量控制;RVS的验收测试;RVS在临床使用过程中的持续质量控制;使用RVS过程中的典型错误类型;执行RVS验收测试的具体测试例。  相似文献   
35.
Medical education fellowship programs (MEFPs) are a form of faculty development contributing to an organization’s educational mission and participants’ career development. Building an MEFP requires a systematic design, implementation, and evaluation approach which aligns institutional and individual faculty goals. Implementing an MEFP requires a team of committed individuals who provide expertise, guidance, and mentoring. Qualified MEFP directors should utilize instructional methods that promote individual and institutional short and long term growth. Directors must balance the use of traditional design, implementation, and evaluation methodologies with advancing trends that may support or threaten the acceptability and sustainability of the program. Drawing on the expertise of 28 MEFP directors, we provide twelve tips as a guide to those implementing, sustaining, and/or growing a successful MEFP whose value is demonstrated by its impacts on participants, learners, patients, teaching faculty, institutions, the greater medical education community, and the population’s health.  相似文献   
36.
Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders, including Huntington disease [caused by expanded CAG repeats (CAGr) in the HTT gene], and amyotrophic lateral sclerosis [ALS, possibly caused by expanded GGGGCC repeats (G4C2r) in the C9ORF72 gene], of which the molecular mechanisms remain unclear. Here, we demonstrated that lowering the Drosophila homologue of tau protein (dtau) significantly rescued in vivo neurodegeneration, motor performance impairments, and the shortened life-span in Drosophila expressing expanded CAGr or expanded G4C2r. Expression of human tau (htau4R) restored the disease-related phenotypes that had been mitigated by the loss of dtau, suggesting an evolutionarily-conserved role of tau in neurodegeneration. We further revealed that G4C2r expression increased tau accumulation by inhibiting autophagosome–lysosome fusion, possibly due to lowering the level of BAG3, a regulator of autophagy and tau. Taken together, our results reveal a novel mechanism by which expanded G4C2r causes neurodegeneration via an evolutionarily-conserved mechanism. Our findings provide novel autophagy-related mechanistic insights into C9ORF72-ALS and possible entry points to disease treatment.Electronic supplementary materialThe online version of this article (10.1007/s12264-020-00518-2) contains supplementary material, which is available to authorized users.  相似文献   
37.
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
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40.
目的 比较生物型与骨水泥型假体全髋关节置换术(THA)治疗老年移位型股骨颈骨折(DFNF)的临床疗效.方法 前瞻性纳入2015年7月—2018年6月佳木斯大学附属第一医院骨科收治的老年DFNF患者128例,男性71例,女性57例;年龄61~84岁,平均72.7岁.骨折原因:跌伤75例,撞伤32例,高处坠落伤21例.依据随机数字表法分为生物型假体THA组(BPTHA组,n=64)与骨水泥型假体THA组(CPTHA组,n=64).BPTHA组行生物型假体髋关节置换,CPTHA组行骨水泥型假体髋关节置换.观察两组术中出血量、手术时间、术后引流量等围术期指标及住院时间.比较术前及术后6、12个月髋关节功能(Harris),血清前列腺素缓激肽(BK)、5-羟色胺(5-HT)等疼痛因子水平及视觉模拟评分(VAS),血清淀粉样蛋白A(SAA)、C反应蛋白(CRP)、红细胞沉降率(ESR)等炎性反应指标水平;分析术后并发症发生情况.结果 两组术中出血量、手术时间、术后引流量差异均无统计学意义(P>0.05);BPTHA组住院时间长于CPTHA组[(19.76±2.24)d vs.(15.37±1.71)d,P<0.05].术后6个月,BPTHA组Harris评分低于CPTHA组[(81.72±8.37)分vs.(86.68±8.85)分,P<0.05];术后12个月,BPTHA组Harris评分高于CPTHA组[(95.54±9.67)分vs.(90.72±9.12)分,P<0.05].术后6个月,BPTHA组血清BK、5-HT、SAA、CRP、ESR水平及VAS均高于CPTHA组(P<0.05);术后12个月,BPTHA组血清BK、5-HT、SAA、CRP、ESR水平及VAS均低于CPTHA组(P<0.05).BPTHA组并发症发生率为3.13%,CPTHA组并发症发生率为4.69%,两组比较差异无统计学意义(P>0.05).结论 BPTHA、CPTHA均可应用于老年DFNF的临床治疗,但CPTHA近期疗效优于BPTHA,而BPTHA远期疗效优于CPTHA.  相似文献   
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