大黄素和小剂量雌激素合用对去卵巢大鼠骨质疏松的预防作用

目的观察大黄素和小剂量雌激素联合应用对去卵巢大鼠骨质疏松的预防作用.方法3月龄大鼠双侧卵巢去除术后预防用药90 d.用骨组织形态计量学方法,测定大鼠胫骨近端松质骨静态参数和动态参数,观察骨物理生长指标、血清生化指标和器官指数.结果大黄素90 mg·kg-1·d-1和己烯雌酚5 μg·kg-1·d-1联合应用可抑制去卵巢大鼠的破骨细胞活性,完全对抗其骨转化率增高和骨量丢失的骨质疏松症状,与己烯雌酚30 μg·kg-1·d-1的作用相当,且降低己烯雌酚对子宫和肝脏的刺激作用.结论大黄素和小剂量己烯雌酚联合应用可预防去卵巢大鼠骨质疏松.     

Introducing dental students to clinical patient care: The complete denture prosthodontics transition clinic

Using complete denture treatment as an introduction to clinical patient care for dental students, the purposes of the Complete Denture Prosthodontics Transition Clinic at the University of Colorado School of Dentistry are to reduce the time lapse between the preclinical complete denture prosthodontics course and the first denture patient experience, and to encourage development of student self-confidence and skills. In the 2002 spring semester, faculty at the University of Colorado School of Dentistry initiated the Complete Denture Prosthodontics Transition Clinic for DS-II (second-year) dental students, as an introduction to clinical patient care. Each patient was assigned to a team of two dental students. Three Division of Prosthodontics faculty members staffed each clinic session, providing a student-to-faculty ratio of approximately 6.6:1 and a patient-to-faculty ratio of approximately 3.3:1. All DS-II students in the Class of 2004 delivered their first complete dentures no later than 8 months (average, 184 days) after the last day of the preclinical complete denture prosthodontics course. The time from the diagnostic appointment through the denture placement appointment averaged 39 days for patients treated in this program, compared with an average of 98 days or more for previous classes. The program was successful in achieving the goal of reducing the time lapse between the preclinical complete denture prosthodontics course and the first denture patient experience.     

NEW DEVICE TO PERFORM COAGULATION AND IRRIGATION SIMULTANEOUSLY DURING ENDOSCOPIC SUBMUCOSAL DISSECTION USING AN INSULATION‐TIPPED ELECTROSURGICAL KNIFE

Background: Although bleeding is an unavoidable complication of endoscopic submucosal dissection (ESD), endoscopic hemostasis using an insulation‐tipped electrosurgical knife (IT) knife is impossible because an insulator is mounted at the tip of the knife. We have developed a new type of hood which could perform both coagulation and irrigation simultaneously. Methods: Our new device was fabricated by drilling a side hole in the cap portion of a conventional transparent hood followed by attaching a machined papillotomy knife to the exterior surface of the hole. Results: Our new hood was useful for hemorrhage during ESD using IT knife. Conclusions: With this method, endoscopic hemostasis using IT knife is easy, as hemostatic procedure can be performed under irrigation and coagulation using conventional endoscopy.     

83例6个月以下婴儿室间隔缺损的外科治疗

目的 总结外科手术治疗小婴儿期室间隔缺损(VSD)的临床经验.方法 对2000-2005年83例＜6月龄VSD患儿,年龄12 d至6(4.3±1.2)个月,体重3～6.5(5.1±0.8)kg.膜周部VSD 74例,干下型VSD 8例,膜周部并肌部VSD1例.术前中、重度肺动脉高压69例(83.1%).所有患儿均在浅低温体外循环下手术.结果 全组手术死亡4例,手术病死率为4.8%.术后主要并发症为肺动脉高压危象、肺部感染和心律失常.结论 随着麻醉、体外循环、手术技术和围术期监护处理措施的进步,在小婴儿期施行VSD的外科手术已成为安全的治疗方式.术后对肺高压的处理是手术成功的关键.     

运动疲劳对大鼠十二指肠电活动的影响

本文报道了大鼠十二指肠电活动在运动疲劳前后的数值。结果表明：在运动疲劳后，快波、慢波振幅明显增加，而其频率却减少；Ⅰ相缩短，Ⅱ相延长，Ⅲ相、Ⅳ相及ＩＤＭＥＣ周期无显著变化；并在运动疲劳后９．７±２．４ｍｉｎ内出现不规律的食后型的电活动。这些改变可了解运动疲劳对消化系统的影响。     

Effects of galanin on insulin and glucagon secretion in the rat

Galanin-like immunoreactivity has been visualized in nerve fibers in the islets of Langerhans, suggesting an involvement of galanin in the neural regulation of islet function. In this study, we investigated the effects of galanin on basal and stimulated insulin and glucagon secretion by infusing the peptide at three different dose rates in rats. We also studied the direct effect of galanin on insulin secretion from freshly isolated rat islets. At 320 pmol/kg/min, but not at 20 or 80 pmol/kg/min, galanin lowered basal plasma insulin levels. In contrast, basal plasma glucagon levels were lowered by galanin already at 20 and 80 pmol/kg/min. Furthermore, galanin inhibited both glucose- and arginine-induced insulin release at all three dose levels, whereas arginine-induced glucagon release was not affected by galanin. Glucose-stimulated insulin secretion from isolated rat islets was dose-dependently suppressed by galanin (10^-6-10^-8M). Therefore, it is concluded that galanin in rats inhibits insulin secretion, both in vivo and in vitro, and that at lower dose levels, the peptide also inhibits basal glucagon release.     

去势后大鼠海马结构一氧化氮合酶阳性神经元的变化

目的：观察去势后大鼠海马结构一氧化氮合酶（NOS）阳性神经元的变化。方法：用黄递酶组织化学染色方法观察切除双侧卵巢后雌后SD大鼠海马结构NOS阳性神经元的形态，分布的变化，并进行计算机图像分析。结果：去势后海马结构NOS阳性神经元分布变化有区域差异性；NOS阳性神经元在下托、海马（CA）一区邻近下托的部分、CA三区、CA四区（CA4）和齿状回（DG）数目明显减少，而在CA二区数目明显明显增多，CA4和DG的NOS阳性神经元平均密度降低，胞体的平均周长和平均截面积都明显减少。结论：雌激素可能通过影响海马结构NOS的表达来影响学习和记忆。     

大鼠皮质神经元的体外培养和纯化

目的：探讨大鼠皮质神经元分离纯化的有效方法。方法：取胎鼠大脑皮质细胞，分别在不同的培养液中进行原代培养，利用相差显微镜对培养的细胞进行动态观察；并以免疫细胞化学技术对神经元进行染色。结果：在相差显微镜下可见加用N2添加剂和胎牛血清培养的神经元生长良好，胞体形态多样，突起数目多，长度长，与邻近神经元的胞体或突起形成接触，而胶质细胞则大量死亡，神经元纯化率达94％以上，未加用N2添加剂培养的神经元胶质细胞大量存在，神经元纯化率达50％左右。结论：N2添加剂和胎牛血清联合应用可使大鼠皮质神经元得到良好的生长和有效纯化。     

糖尿病大鼠视网膜血管内皮生长因子与一氧化氮的变化

目的：探讨糖尿病大鼠视网膜血管内皮生长因子（VEGF）与一氧化氮（NO）的变化及其在糖尿病视网膜病变（DR）发生发展过程中的作用。方法：选择健康成年SD大鼠，随机分成正常对照组，糖尿病1月（DM1），糖尿病3月（DM3）和糖尿病5月（DM5）组，一次性腹腔注射链佐菌素（STZ）诱发糖尿病模型，应用免疫组织化学方法观察各组视网膜组织VEGF的表达情况，并检测各组视网膜组织中一氧化氮合酶（NOS）活性和NO含量变化。结果：3个月时，糖尿病大鼠视网膜VEGF表达增强，NOS活性增强，NO含量增高，5个月时，糖尿病大鼠视网膜表达进一步增强，而NOS活性开始减弱，NO含量减少，结论：糖尿病大鼠视网膜VEGF的过度表达和NOS活性，NO含量的变化在DR的发生发展过程中起重要作用。     

烹调油烟致大小鼠肺癌的实验研究

[目的]了解烹调油烟（cooking oil fumes，COF）的动物致癌性。[方法]采用动式染毒法给Balb／c小鼠（雌雄各半）吸入COF浓度为9．09、20．65、38．85mg／m^3，染毒1次／1～2d，30min／次，共150次，计8个月；SD大鼠（雌雄各半）吸入COF浓度为6、88、15．06、35．33mg／m^3，染毒1次／2d，30min／次，共191次，计12．5个月。分别制备COF慢性中毒动物模型；两实验均设空白对照组，吸入与实验组相同温度的清洁空气。[结果]COF诱发Balb／c小鼠实验组肺癌总发生率为18、95％（29／153），低、中、高浓度组肺癌发生率分别为15．09％、20、00％和22．00％，与对照组差异均有显著性。但低、中、高三组间差异无显著性（P〉0．05）；COF诱发SD大鼠肺癌总发生率为9、10％（9／99），低、中、高浓度组肺癌发生率分别为6．45％、8．57％、12．12％，高浓度组肺癌发生率高于对照组（P〈0．05）。各性别组间肺癌发生率的差别无显著性（P〉0．05）。[结论]COF可以诱导Balb／c小鼠和SD大鼠肺癌，诱发的肺癌主要为肺腺癌（小鼠28／29，大鼠7／9），余为小细胞肺癌。