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1.
目的: 探讨银杏叶制剂联合地塞米松在老年突聋治疗中对血清炎症指标的影响。方法: 按随机数字表法将我院2016年7月-2021年7月收治的102例老年突聋患者分入两组(各51例)。对照组用地塞米松治疗,治疗组加用银杏叶制剂治疗。观察两组治疗前后纯音听阈和血管内皮功能指标[超氧化物歧化酶(SOD)、脂质过氧化物(LPO)、一氧化氮(NO)]、血清炎症指标[肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)、白细胞介素-6(IL-6)],分析其疗效与不良反应。结果: 与对照组比较,治疗组总有效率更高(96.08%vs 82.35%)(χ2=4.993,P=0.025);两组治疗后各频率点阈值均下降,且相比对照组,治疗组治疗后各频率点阈值更低(P<0.05);治疗后两组SOD、NO水平均升高,LPO水平降低(P<0.05),且相比对照组,治疗组治疗后SOD、NO水平更高,LPO水平更低(P<0.05);治疗后两组血清TNF-α、CRP、IL-6水平降低,且相比对照组,治疗组TNF-α、CRP、IL-6水平更低(P<0.05);治疗组不良反应发生率5.88%,对照组为9.80%,两组比较差异无统计学意义(P=0.543,χ2=0.461)。结论: 银杏叶制剂联合地塞米松治疗老年突聋患者疗效理想,能恢复各频率点听力,安全可靠,推测改善患者血管内皮功能和炎症因子水平是其重要作用机制。  相似文献   
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目的 探讨蜂巢提取物Elixir-X对自然衰老及辐射衰老小鼠的影响,为Elixir-X的进一步研发提供药理学基础。方法 采用小鼠肝脏切除术建立自然衰老小鼠模型,将其分为空白对照组、Elixir-X组、白藜芦醇组及模型组,连续给药7 d后,检测小鼠70%肝脏切除后的再生过程中,衰老细胞、肝脏功能恢复与肝脏再生的变化,观察Elixir-X对自然衰老的影响;采用60CO辐射法建立辐射衰老小鼠模型,将其分为模型组、空白对照组、白藜芦醇组、Elixir-X高、低剂量组,通过检测小鼠肠隐窝干细胞再生、小肠绒毛结构以及衰老细胞的变化,对比不同剂量Elixir-X对辐射后衰老的影响。结果 在肝脏切除术的小鼠模型中,Elixir-X组的肝功能水平明显低于模型组的肝脏自然再生小鼠,显著促进了肝功能恢复(P<0.05);同时与模型组相比,Elixir-X组清除了肝脏切除后再生过程中产生的衰老细胞(P<0.05),Ki-67的着色斑块明显增加,促进肝脏的再生,且肝血窦的扫描电镜影像结果中Elixir-X组肝血窦再生加快。60CO辐照小鼠模型中,与模型组相比,Elixir-X组有效促进辐照后肝脏功能恢复(P<0.05),Elixir-X高剂量组体重也恢复到正常水平,与空白对照组无显著差异;与模型组相比,Elixir-X低剂量组小肠的β-Gal着色细胞减少,Elixir-X高剂量组甚至能更有效地减少衰老细胞(P<0.05);小肠HE染色的结果中,Elixir-X组小肠绒毛结构得到恢复;Ki-67的IHC染色中,与模型组相比,Elixir-X组着色板块更多,且着色区域都在肠隐窝干细胞位置。结论 Elixir-X能有效清除肝脏切除术引起的自然衰老与辐射引起的损伤性衰老细胞,对衰老具有显著地抑制作用。  相似文献   
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《Saudi Dental Journal》2021,33(7):518-523
ObjectiveOptimal tooth reduction is a key requirement for aesthetics, function, and the longevity of fixed restorations. Research has demonstrated that controlled and conservative tooth preparation is crucial for the long-term success of adhesive restorations. Different techniques of fabricating reduction guides have been previously reported in literature. The present technical note describes the fabrication technique and clinical application of a customized metal preparation reduction guide.Material and methodPatient presented with tilted maxillary left central incisor. The flared-out part of the tooth was modified prior to veneer restoration preparation. Resin pattern reduction guide was fabricated on the diagnostic cast with a window on the tilted mesial portion of the tooth. After intraoral evaluation, resin pattern guide was casted. Metal reduction guide was place intraorally and reduction was provided on the exposed surface of the tooth. After the removal of the tilted portion, a harmonious arch form allowed the clinician to provide adequate evaluation and preparation for veneer restorations.ResultsThe device demonstrated good practical value, allowing for selective and controlled reduction of tooth structure, and definitive protection of adjacent tooth surfaces from iatrogenic damage. The clinical outcome successfully addressed the patient’s restorative and aesthetic needs, and the veneer was stable 2 years postoperatively.ConclusionUse of a metal guide assists clinicians to provide a more predictable reduction of a desired tooth surface, while decreasing the risk of compromising the other/adjacent tooth surfaces.  相似文献   
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目的:建立高效液相色谱-串联质谱法测定雷公藤制剂中雷公藤甲素、雷公藤内酯酮、雷公藤晋碱、雷公藤次碱和雷公藤红素的含量。方法:采用电喷雾正电离模式和多反应监测模式。雷公藤甲素、雷公藤内酯酮、雷公藤晋碱和雷公藤次碱含量测定,以含5 mmol·L-1碳酸氢铵的水溶液和纯甲醇作为流动相,采用梯度洗脱方式在ACE UltraCore SuperPhenylHexyl(2.1 mm×50.0 mm,5 μm)色谱柱上进行分离。雷公藤红素含量测定,以含0.5%甲酸的水溶液和含0.1%甲酸的乙腈作为流动相,采用等度洗脱在ACE Excel C18-AR(2.1 mm×50.0 mm,5 μm)色谱柱上进行分离。结果:雷公藤甲素、雷公藤内酯酮、雷公藤晋碱、雷公藤次碱和雷公藤红素分别在2.4~1 200,2.0~1 000,80~40 000,80~40 000和10~5 000 ng·mL-1范围内线性关系良好,平均加样回收率分别为 94.56%,102.36%,93.27%,95.67%和99.82%,RSD均低于5.13%。结论:本方法运行时间短,灵敏度高,精密度和重复性好,适用于雷公藤制剂中雷公藤甲素、雷公藤内酯酮、雷公藤晋碱、雷公藤次碱和雷公藤红素5种活性成分定量检测,可为雷公藤制剂多指标质量控制提供实验依据。  相似文献   
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董微  张博  邵超 《西部医学》2019,31(5):679-682+688
【摘要】目的 探讨鲜天南星水提取物对小鼠子宫纤维瘤的抑制作用及对小鼠雌激素水平的影响。方法 选取SD健康雌性小鼠30只,随机分为正常组、模型组、实验组3组,每组各10只,对模型组、实验组进行子宫纤维瘤模型建立,正常组不作处理。实验组小鼠予以鲜天南星水提取物进行干预,正常组、模型组小鼠注射等体积生理盐水。对小鼠子宫重及子宫系数进行统计计算,酶联免疫吸附试验法检测雌二醇(Estradiol,E2)、孕酮(Progesterone,P)、卵泡刺激素(Follicle stimulating hormone,FSH)、黄体生成激素(Luteinizing Hormone,LH)水平。结果 干预后,模型组及实验组小鼠子宫重及子宫系数均高于正常组,实验组小鼠子宫重及子宫系数均低于模型组(P<0.05);干预后,模型组及实验组小鼠血清E2、P、FSH、LH水平均高于正常组,但实验组小鼠血清E2、P、FSH、LH水平均低于模型组(P<0.05)。结论 鲜天南星水提取物可对小鼠子宫纤维瘤起到一定的抑制作用,并能对E2、P、FSH、LH等激素水平进行调控,为子宫纤维瘤的临床治疗提供一定的理论依据,值得临床借鉴。  相似文献   
9.
《Journal of endodontics》2020,46(11):1726-1732
IntroductionThe aim of the present study was to evaluate the morphologic changes on the apical foramen and the formation of dentinal microcracks after foraminal enlargement in straight and curved root canals using scanning electron microscopic (SEM) and micro–computed tomographic (micro-CT) analyses.MethodsSixty teeth were selected and divided into 2 experimental groups: GI (incisors/straight group, n = 30) and GM (molars/curved group, n = 30). Each group was divided into 2 subgroups (n = 15) according to the analysis performed: SEM or micro-CT analysis. The incisors and mesiobuccal canal of molars were instrumented with Reciproc Blue R25 instruments (VDW, Munich, Germany) using standardized shaping procedures in the apical foramen and 1 mm beyond. The occurrence of foraminal deformation was analyzed by scanning electron microscopy. The z test was used for statistical analysis (P < .05). Micro-CT imaging was used to observe the presence of microcracks in the root apical third. Afterward, pre- and postoperative cross-sectional images were screened to identify the presence of dentinal defects.ResultsThe curvature of the canal did not influence the occurrence of foraminal deformation either for instrumentation in the foramen or for instrumentation beyond the foramen (P > .05). It was also observed that the increase in the working length did not influence the appearance of new deformations in the GI/SEM and GM-SEM groups (P > .05). Qualitative micro-CT analysis showed the presence of dentinal defects in 0.8% (112) and 1.5% (208) of the cross sections of incisors and molars, respectively, from a total of 13,987 slices. All dentinal defects identified in the analysis of any postoperative scans were already present in the corresponding preoperative images. Therefore, no new microcracks were observed after root canal preparation.ConclusionsThe preparation of straight and moderately curved root canals with Reciproc Blue, regardless of the working length, did not influence the occurrence of apical foramen deformations and did not cause the formation of dentinal microcracks.  相似文献   
10.
Evaluation of abutment tooth shape for preformed metal crowns for primary teeth in preclinical training depends on the subjective opinion of the instructor providing the training. Thus, the student's grade will likely vary according to teacher grading. In this study, we explored the potential for objective evaluation by comparing evaluations performed by teaching personnel (teacher grading) of abutment teeth for preformed metal crowns for primary teeth prepared by students at a dental school with evaluation by a three-dimensional (3D) laser morphometric system (system grading). The subjects of the evaluations were 139 abutment teeth for preformed metal crowns for primary teeth that had been prepared by fourth-year students at Asahi University School of Dentistry during preclinical pediatric dentistry training. A tooth prepared by a teacher following instruction criteria was used as the reference tooth, and system grade points were calculated from deductions made for insufficient and excessive cutting. Teacher grade points varied among teachers. We found that teachers prioritized contours of the margin, buccal and lingual sides, and adjacent surfaces in their evaluations. System grading showed that most students carried out insufficient cutting. The mean (SD) teacher and system grade points were 57.7 (9.7) and 75.7 (4.7), respectively, and these grade points were positively correlated (r = 0.500). System grading provides a simple 3D visual assessment of insufficient and excessive cutting that can be used for instructing students.  相似文献   
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