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91.
目的 探讨采用基于“人工智能(AI)的骨龄辅助评价系统(上海初云医疗科技有限公司与四川大学华西第二医院合作开发)”(以下简称为AI系统)对完全性生长激素缺乏症(CGHD)患儿诊断及骨龄评价准确性。方法 选择2014年7月至2019年11月,于四川大学华西第二医院确诊的66例来自四川地区CGHD患儿为研究对象,纳入研究组。选择同期于病例收集医院儿童保健科进行骨龄测定的67例来自四川地区身高达标儿童作为对照,纳入对照组。对每例受试儿进行左手腕关节正位X射线摄片骨龄测定,由2位医师采用《TW2骨龄评分法中国未成年人南方标准》(以下简称为TW2CHN)》与《TW3骨龄评分法标准》(以下简称为TW3),盲法评价受试儿TW2CHN-桡、尺、掌指骨(RUS)与TW2CHN-腕骨(carpal)、TW2CHN-20、TW3-RUS及TW3-carpal骨龄(以下简称为5种传统骨龄),以及以同性别、年龄身高达... 相似文献
92.
93.
针刺镇痛在临床上被广泛应用。针刺的神经传导通路与机体痛觉传导通路基本相似,对周围神经和中枢神经均有一定的影响,因此推断这可能是针刺缓解疼痛的一种调节机制。本文总结了近五年针刺治疗各种疼痛疾病的机制研究,从传导通路上分析得知针刺能激发神经元活性,改善周围神经的病理变化,增加神经元之间突触传递,修复受损的周围神经以缓解疼痛。此外,应用针刺或加用电针治疗痛症,能改善大脑内与疼痛相关各功能区之间的联系,对镇痛起到一定的中枢调控作用。在研究中还发现针刺能减少病变区炎性反应和细胞凋亡,增加细胞自噬和血管调节因子的表达。这些反应之间常存在一定的相互作用,共同缓解机体疼痛症状。然而,临床中针刺手法及辅助方法众多,治疗选取的相关穴位各异,根据疾病定位定性后选择最优组合方式是今后总结经验的重要目标。 相似文献
94.
Yu-si CHENG De-zai DAI Yin DAI 《中国药理学报》2009,(8):1099-1106
Aim: Spatial dispersion of bioactive substances in the myocardium could serve as pathological basis for arrhythmogenesis and cardiac impairment by β-adrenoceptor stimulation. We hypothesized that dispersed NADPH oxidase, protein kinase Cε (PKCε), early response gene (ERG), and matrix metalloproteinase 9 (MMP-9) across the heart by isoproterenol (ISO) medication might be mediated by the endothelin (ET) - ROS pathway. We aimed to verify if ISO induced spatially heterogeneous distribution of pPKCε, NAPDH oxidase, MMP-9 and ERG could be mitigated by either an ET receptor antagonist CPU0213 or iNOS inhibitor aminoguanidine. Methods:Rats were treated with ISO (1 mg/kg sc) for 10 days, and drug interventions (mg/kg) either CPU0213 (30 sc) or aminoguanidine (100 ip) were administered on days 8-10. Expression of NADPH oxidase, MMP-9, ERG, and PKCε in the left and right ventricle (LV, RV) and septum (S) were measured separately. Results: Ventricular hypertrophy was found in the LV, S, and RV, in association with dispersed QTc and oxidative stress in ISO-treated rats. mRNA and protein expression of MMP-9, PKCε, NADPH oxidase and ERG in the LV, S, and RV were obviously dispersed, with augmented expression mainly in the LV and S. Dispersed parameters were re-harmonized by either CPU0213, or aminoguanidine. Conclusion: We found at the first time that ISO-induced dispersed distribution of pPKCε, NADPH oxidase, MMP-9, and ERG in the LV, S, and RV of the heart, which were suppressed by either CPU0213 or aminoguanidine. It indicates that the ET-ROS pathway plays a role in the dispersed distribution of bioactive substances following sustained β-receptor stimulation. 相似文献
95.
Aim: Paeonol (2'-hydroxy-4'-methoxyacetophenone) from Cortex moutan root is a potential therapeutic agent for atherosclerosis. This study sought to investigate the mechanisms underlying anti-inflammatory effects of paeonol in rat vascular endothelial cells (VECs) in vitro.
Methods: VECs were isolated from rat thoracic aortas. The cells were pretreated with paeonol for 24 h, and then stimulated with ox-LDL for another 24 h. The expression of microRNA-21 (miR-21) and PTEN in VECs was analyzed using qRT-PCR. The expression of PTEN protein was detected by Western blotting. TNF-α release by VECs was measured by ELISA.
Results: Ox-LDL treatment inhibited VEC growth in dose- and time-dependent manners (the value of IC50 was about 20 mg/L at 24 h). Furthermore, ox-LDL (20 mg/L) significantly increased miR-21 expression and inhibited the expression of PTEN, one of downstream target genes of miR-21 in VECs. In addition, ox-LDL (20 mg/L) significantly increased the release of TNF-α from VECs. Pretreatment with paeonol increased the survival rate of ox-LDL-treated VECs in dose- and time-dependent manners. Moreover, paeonol (120 μmol/L) prevented ox-LDL-induced increases in miR-21 expression and TNF-α release, and ox-LDL-induced inhibition in PTEN expression. A dual-luciferase reporter assay showed that miR-21 bound directly to PTEN's 3'-UTR, thus inhibiting PTEN expression. In ox-LDL treated VECs, transfection with a miR-21 mimic significantly increased miR-21 expression and inhibited PTEN expression, and attenuated the protective effects of paeonol pretreatment, whereas transfection with an miR-21 inhibitor significantly decreased miR-21 expression and increased PTEN expression, thus enhanced the protective effects of paeonol pretreatment.
Conclusion: miR-21 is an important target of paeonol for its protective effects against ox-LDL-induced VEC injury, which may play critical roles in development of atherosclerosis. 相似文献
Methods: VECs were isolated from rat thoracic aortas. The cells were pretreated with paeonol for 24 h, and then stimulated with ox-LDL for another 24 h. The expression of microRNA-21 (miR-21) and PTEN in VECs was analyzed using qRT-PCR. The expression of PTEN protein was detected by Western blotting. TNF-α release by VECs was measured by ELISA.
Results: Ox-LDL treatment inhibited VEC growth in dose- and time-dependent manners (the value of IC50 was about 20 mg/L at 24 h). Furthermore, ox-LDL (20 mg/L) significantly increased miR-21 expression and inhibited the expression of PTEN, one of downstream target genes of miR-21 in VECs. In addition, ox-LDL (20 mg/L) significantly increased the release of TNF-α from VECs. Pretreatment with paeonol increased the survival rate of ox-LDL-treated VECs in dose- and time-dependent manners. Moreover, paeonol (120 μmol/L) prevented ox-LDL-induced increases in miR-21 expression and TNF-α release, and ox-LDL-induced inhibition in PTEN expression. A dual-luciferase reporter assay showed that miR-21 bound directly to PTEN's 3'-UTR, thus inhibiting PTEN expression. In ox-LDL treated VECs, transfection with a miR-21 mimic significantly increased miR-21 expression and inhibited PTEN expression, and attenuated the protective effects of paeonol pretreatment, whereas transfection with an miR-21 inhibitor significantly decreased miR-21 expression and increased PTEN expression, thus enhanced the protective effects of paeonol pretreatment.
Conclusion: miR-21 is an important target of paeonol for its protective effects against ox-LDL-induced VEC injury, which may play critical roles in development of atherosclerosis. 相似文献
96.
目的:探讨以感染症状为首发表现的亚急性甲状腺炎临床表现及治疗。方法回顾性分析我院54例以感染症状为首发表现的亚急性甲状腺炎患者的临床资料。结果患者发病年龄以30~60岁多见,占85%;发病月份主要集中在5~10月;患者均有发热及相应感染的表现。颈部不适及甲状腺触痛的患者占72.2%;血白细胞升高患者占40.7%;全部患者均有红细胞沉降率增快;94.4%的患者伴甲状腺功能亢进;31%的患者有典型的甲状腺超声表现。非甾体类及肾上腺糖皮质激素治疗有效。结论对发热伴咽痛表现的患者应注意仔细查体,特别是伴无其他病因而红细胞沉降率明显增快的患者应完善实验室检查除外亚急性甲状腺炎的诊断。 相似文献
97.
本文介绍了药物转运体在药物排泄过程中的作用,探讨了其在新药研发和临床应用中的可能性。通过对药物转运体功能的了解和利用,可以开发出对某些器官有靶向性的药物,或避免药物分布到某些器官中,从而提高药物的疗效,降低其毒副作用;也可以通过对转运体介导的药物相互作用及肝肠循环的研究,指导临床更加安全有效的用药。在药物研发的初始阶段,就开始重视其药动学特性,这一观念近年来已被很多人所接受。对药物转运体的深入认识和利用,建立高通量的药物转运体筛选体系,对于加速新药研发的进程将具有极其重要的意义。 相似文献
98.
为快捷诊断上呼吸道肺炎衣原体感染,用肺炎衣原体PstI474片段特异性聚合酶链式反应(polymerasechainreaction,PCR)法检测了急性上呼吸道炎症患者局部拭子标本。同时以微量免疫荧光法检测了血清中肺炎衣原体特异性抗体。结果在175例患者拭子标本中,PCR阳性49例,阳性率28%;荧光抗体阳性45例,阳性率25.7%。两者相符率91.8%。表明肺炎衣原体PstⅠ474片段特异性PCR法检测鼻咽喉部肺炎衣原体感染是一个较敏感和特异的方法 相似文献
99.
外伤性鼓膜穿孔是耳鼻咽喉科的常见病、多发病,近年来有上升趋势。鼓膜穿孔破坏了鼓膜的正常结构并影响鼓膜的正常生理功能,穿孔后鼓室与外耳道直接相通,为病原微生物侵入中耳打开了门户,且鼓膜穿孔患者常有不同程度的耳闷、耳鸣及听力下降等症状,对患者的生理及心理造成一定影 相似文献
100.
目的 研究乌鲁木齐地区非综合征性聋患者线粒体12S rRNA基因突变情况。方法 收集乌鲁木齐非综合征性聋患者标本609例,对其进行临床和分子遗传学评估。结果 12S rRNA基因突变分析共发现11个突变位点,已知的A1555G、961DelT、C1494T突变分别占2.96%,1.15%,0.16%。另外A1047G突变相关报道较少,A1585G突变未见相关报道。其他突变均为多态性位点。结论 线粒体12S rRNA突变是引起遗传性聋的重要因素,此次乌鲁木齐地区线粒体12S rRNA A1555G突变在聋病人群中的检出率与前期报道相比有所降低,可能与耳毒性药物使用量降低有关。A1047G与新发现的A1585G突变是否与聋相关,还需进一步研究。对筛查中阳性突变携带者及其母系家庭成员需告知氨基糖苷类抗生素使用风险,使其避免使用,逐步降低药物性聋的发生率。 相似文献