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111.
目的 研究耳叶苔科植物灰瓣耳叶苔Frullania muscicola Steph.的化学成分。方法 用硅胶、SephadexLH-20柱层析,通过理化性质鉴定及光谱数据分化确定化合物的结构。结果 分离到3个甾体化合物和4个黄酮化合物,分别鉴定为豆甾醇二十烷酸酯(I)、谷甾醇(Ⅱ)、洋芹素-7,4′-二甲醚(Ⅲ)、黄芩素-6,4′-二甲醚(Ⅳ)、6-羟基本犀草素-6,3′-二甲醚(Ⅴ)、黄芩素-6-甲醚(Ⅳ)和胡萝卜苷(Ⅶ )。结论 化合物Ⅰ为新化合物,其余6个化合物均为首次从该植物中分得。  相似文献   
112.
Histocompatibility is crucial in effecting survivalof allografts.Due to differences in histocompatibilitybetween donor and recipient,rejection would happento some extent after transplantation. Therefore,theevaluation of differences in histocompatibility betweendonor and recipient would be contributive to selectionof donor and judgement on prognosis oftransplantation. HLA typing and mixed lymphocyticreaction (MLR) are the classical methods to evaluatethe histocompatibility between donor and r…  相似文献   
113.
目的探讨人参皂甙(ginsentosides,Gin)单体Rgl及维拉帕米(verapamil,Ver)对豚鼠心肌细胞内游离钙浓度([Ca2+]i)变化的影响.方法采用离体豚鼠心脏Langendorff法灌注,胶原酶Ⅰ型分离心肌细胞,用荧光指示剂方法(Fura-2/AM)标记心肌([Ca2+]i)变化.将心肌细胞悬液分为3组对照组、Rgl组和Ver组.观察缺氧后心肌[Ca2+]i的变化.结果(1)正常氧状态心肌[Ca2+]i均值为(125.4±10.3)nmol/L(n=20).(2)缺氧状态下,心肌[Ca2+]i增加与缺氧时间(程度)直线相关,相关系数r为0.98左右.(3)Rgl对缺氧后心肌[Ca2+]i增加明显延缓.结论Rgl在缺氧条件下,使心肌[Ca2+]i明显下降,从而阻止心肌细胞内钙超载,其作用与Ver相似,我们认为Rgl具有心肌细胞的保护作用.  相似文献   
114.
目的;研究DYS19基因座在中国北方汉族、维吾尔族、哈萨克族群体中的遗传多态性及其法医学应用。方法:应用聚合酶链反应后变性聚丙烯酰胺凝胶电泳分离扩增产物结合银染显带的方法,对101例北方汉族、56例维吾尔族、30例哈萨克族无关男性个体的DYS19基因座进行检测。结果:DYS19基因座在3个群体中共检出5种等位基因,基因频率分布范围分别为0.069-0.594,0.071-0.500,0.100-0.667;个人识别机率分别为0.600,0.675,0.491。χ^2检验表明等位基因分布具有明显的人群差异。家系调查符合单体父系遗传方式。结论:DYS19基因座个人识别机率高,属较高鉴别能力的遗传标记系统,且具有明显的人群分布差异,在法医学及人类遗传学研究中具有重要的应用价值。  相似文献   
115.
目的 探讨视黄酸在脂蛋白代谢中的作用。方法 采用冻干浓缩培养液载脂蛋白 RID测定法 ,分别观察 4种不同浓度的视黄酸对培养的人肝癌细胞系 Hep G2细胞载脂蛋白 ( apo) A 、A 、C 、B10 0及 E分泌的影响。结果 视黄酸对 Hep G2细胞 apo A 、A 、B10 0及 C 的分泌均有促进作用 ,对 apo E的分泌则有抑制作用。在本研究条件下 ,当视黄酸的浓度为 2× 10 - 4 m ol/ L时 ,其对 Hep G2细胞 apo分泌的影响作用最大 ,此时apo A 、A 、B10 0和 C 的分泌分别增加 14.3% ( P<0 .0 1)、2 3.8% ( P<0 .0 5 )、16 .1% ( P<0 .0 1)、47.6 % ( P<0 .0 1) ,而 apo E的分泌减少 37.2 % ( P<0 .0 1)。结论 视黄酸对 Hep G2细胞 apo A 、A 、C 、B10 0及 E的分泌有不同的影响  相似文献   
116.
Purtscher 综合征是指身体远隔部位损伤后,发生的一种特殊性视网膜病变。笔者先后遇到 2 例,现报道如下。 1 临床资料 例 1:费某某,男,40 岁,因外伤后左眼视力下降 40 d 入院。40 d 前因车祸致右侧额部及左侧肩胛骨线性骨折,受伤次日始左眼视物模糊,视力逐渐下降,眼前出现固定黑影。入院时眼科检查左眼视力 0.4,前节未见异常,眼底视盘轻度水肿,边界模糊不清,视网膜水肿,呈衣褶样,反光强,视盘周围可见沿各主要静脉走行的条索状出血,呈放射状,颜色淡,视盘颞侧可见数个棉绒斑,约 1/6 PD,黄斑水肿,中心凹反射消失,视野出现中心暗点;右眼视力 1.0,其它未见异常。诊断为 Purtscher 综合征。经类固醇激素、扩血管药物治疗,出院时左眼视力 1.0,眼底水肿及渗出、出血吸收。  相似文献   
117.
Wang  Jue  Wu  Jiang  Xu  Minghuo  Gao  Quanwen  Chen  Baoguo  Wang  Fang  Niu  Hao  Song  Huifeng 《Lasers in medical science》2021,36(6):1275-1282

The focus of treatment of faciocervical scar contractures includes cervical reconstruction and elimination of hypertrophic scars. Unfortunately, most previous studies have neglected the esthetic appearance of scars. In this study, we tried to combine surgical therapy and ultrapulse fractional CO2 laser (UFCL) to eliminate facial scars while restoring neck reconstruction and to establish the optimal conventional management for faciocervical contracture. Thirty-eight individuals were enrolled and divided into two groups. After received cervical release surgeries, comprehensive UFCL therapy group received treatment of UFCL at 3-month intervals, silicone sheets, and pressure garments, while another group only received treatment of silicone sheeting and compression. Twelve months after the termination of therapy, faciocervical scars of both two groups were assessed by two uninvolved physicians according to the Vancouver Scar Scale (VSS), and patients’ satisfaction survey was also recorded by the study participants using a patient four-point satisfaction scale. Thirty-six patients completed the treatment and follow-up. The results show that the VSS scores of both two groups decreased after 12 months, but comprehensive UFCL therapy group dropped more significantly than the conventional treatment group at follow-up session, which was statistically significant (P?<?0.001), and the patient satisfaction was higher than that of the conventional treatment group. This comprehensive treatment combined of surgery, UFCL, silicone sheets, and pressure garments works as an effective and esthetic reconstruction for moderate to severe postburn faciocervical scar contractures.

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118.
Limited evidence has indicated that brain-derived neurotrophic factor (BDNF) may be involved in the neurobiology of premature ejaculation (PE). This study aimed to investigate BDNF levels in the central and peripheral nervous systems of a rapid ejaculation model. Eighteen male rats were selected and classified as ‘sluggish’, ‘normal’ and ‘rapid’ ejaculators on the basis of ejaculation frequency during copulatory behavioural tests. BDNF levels in specific brain regions, spinal cord and serum were determined by enzyme-linked immunosorbent assay (ELISA). Consistent with the results in PE patients, the concentration of serum BDNF decreased significantly from the sluggish rats to normal and rapid rats. Besides, in both brain regions and spinal cord, the sluggish group had the highest BDNF levels, while the rapid group had the lowest BDNF levels. Regression analyses of the expression of BDNF presented positive correlations between serum and brain (r = 0.958, p < .001), and between serum and spinal cord (r = 0.967, p < .001) respectively. Our findings suggested insufficient BDNF in the nervous system and serum may lead to rapid ejaculation. The current study adds to the evidence that BDNF is involved in the regulation of ejaculation.  相似文献   
119.
120.
Smokers are at a higher risk of delayed union or nonunion after fracture repair. Few specific interventions are available for prevention because the molecular mechanisms that result in these negative sequelae are poorly understood. Murine models that mimic fracture healing in smokers are crucial in further understanding the local cellular and molecular alterations during fracture healing caused by smoking. We exposed three murine strains, C57BL/6J, 129X1/SvJ, and BALB/cJ, to cigarette smoke for 3 months before the induction of a midshaft transverse femoral osteotomy. We evaluated fracture healing 4 weeks after the osteotomy using radiography, micro-computed tomography (μCT), and biomechanical testing. Radiographic analysis demonstrated a significant decrease in the fracture healing capacity of smoking 129X1/SvJ mice. μCT results showed delayed remodeling of fracture calluses in all three strains after cigarette smoke exposure. Biomechanical testing indicated the most significant impairment in the functional properties of 129X1/SvJ in comparison with C57BL/6J and BALB/cJ mice after cigarette smoke exposure. Thus, the 129X1/SvJ strain is most suitable in simulating smoking-induced impaired fracture healing. Furthermore, in smoking 129X1/SvJ murine models, we investigated the molecular and cellular alterations in fracture healing caused by cigarette smoking using histology, flow cytometry, and multiplex cytokine/chemokine analysis. Histological analysis showed impaired chondrogenesis in cigarette smoking. In addition, the important reparative cell populations, including skeletal stem cells and their downstream progenitors, demonstrated decreased expansion after injury as a result of cigarette smoking. Moreover, significantly increased pro-inflammatory mediators and the recruitment of immune cells in fracture hematomas were demonstrated in smoking mice. Collectively, our findings demonstrate the significant cellular and molecular alterations during fracture healing impaired by smoking, including disrupted chondrogenesis, aberrant skeletal stem and progenitor cell activity, and a pronounced initial inflammatory response. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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