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151.
目的:观察糖基化终产物(advanced glycation end products,AGEs)对人视网膜色素上皮细胞增殖的影响,以及川芎嗪对AGEs诱导的人视网膜色素上皮细胞增殖的拮抗作用。方法:实验于2003-09/2004-07在中南大学湘雅二医院中心实验室完成。①实验分组:原代培养人视网膜色素上皮细胞,第3 ̄8代用于实验,设空白对照组,DMEM培养基中不加入任何药物;AGEs对照物组,培养液中含100mg/L的AGEs对照物;AGEs组,培养液中含10,50,100,200,400mg/L的AGEs,分别干预视网膜色素上皮细胞24h及48h。②实验操作:川芎嗪干预实验:也设空白对照组;AGEs对照物组;AGEs组,培养液中含100mg/L的AGEs;AGEs 川芎嗪组,培养液中加入10,20,40,80,160,320,640mg/L川芎嗪30min后加入100mg/L的AGEs,分别干预视网膜色素上皮细胞24h。③实验评估:MTT微量酶比色法检测视网膜色素上皮细胞增殖情况。结果:①视网膜色素上皮细胞增殖情况:不同浓度AGEs组细胞增殖率均高于对照物组(P<0.01),100mg/LAGEs组增殖率(24,48h分别为39.45%,31.97%)高于其他组(P<0.01),48h与24h结果一致。②川芎嗪的抑制效应:与AGEs组比较,10,20,40,80,160mg/L川芎嗪对AGEs诱导的视网膜色素上皮细胞增殖无抑制作用(P>0.05),320及640mg/L川芎嗪有抑制作用,其抑制率为8.96%,15.08%(P<0.01)。结论:①AGEs可诱导人视网膜色素上皮细胞增殖。②低浓度川芎嗪对AGEs诱导的人视网膜色素上皮细胞增殖无抑制作用,高浓度川芎嗪具有抑制作用。  相似文献   
152.
Osteoarthritis (OA) is the most prevalent musculoskeletal disease in humans, causing pain, loss of joint motility and function, and severely reducing the standard of living of patients. Cartilage tissue engineering attempts to repair the damaged tissue of individuals suffering from OA by providing mechanical support to the joint as new tissue regenerates. The aim of this study was to create composite three dimensional scaffolds comprised of electrospun poly(D,L‐lactide)/poly(L‐lactide) (PDLA/PLLA) or poly(D,L‐lactide)/polycaprolactone (PDLA/PCL) with salt leached pores and an embedded chitosan hydrogel to determine the potential of these scaffolds for cartilage tissue engineering. PDLA/PLLA‐hydrogel scaffolds displayed the largest compressive moduli followed by PDLA/PCL‐hydrogel scaffolds. Dynamic mechanical tests showed that the PDLA/PLLA scaffolds had no appreciable recovery while PDLA/PCL scaffolds did exhibit some recovery. Primary canine chondrocytes produced both collagen type II and proteoglycans (primary components of extracellular matrix in cartilage) while being cultured on scaffolds composed of electrospun PDLA/PCL. As a result, a composite electrospun embedded hydrogel scaffold shows promise for treating individuals suffering from OA. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
153.
目的用心血管MRI研究心肌梗死的演变特点,评估急性心肌梗死后2d及1周的心血管MRI数据,哪个能更好地预测梗死3个月后的梗死面积及左室功能。材料与方法本研究经当地研究伦理委员会审查批准,并获得病人的书面知情同意书。再灌注的急性心肌梗死48例,分别在发病后  相似文献   
154.
Microbiologic surveillance is essential for murine health maintenance. At our institution, female progeny of inhouse-bred CD1 mice are used in both the transgenic facility and health-surveillance program. To reduce overall animal use, the male progeny, otherwise slated for euthanasia due to a lack of utility, also were enrolled as sentinels. However, veterinary technicians noted excessive fighting among cohoused male surveillance mice that was not resolved by environmental enrichment. After review of factors known to influence aggression in male mice, early castration was selected as the most likely approach to eliminate aggressive behavior among cohoused male mice. Male mice were castrated before 1 mo of age and then placed into the surveillance program. Each week, veterinary technicians recorded all incidences of fighting in cages of castrated and noncastrated male surveillance mice to determine differences between groups. Over a 3-mo period, the overall prevalence of fighting in cages of intact male mice was 64% (14 of 22 cages); although all intact male mice were used preferentially for complete necropsy surveillance time points, one of these cages required separation and 4 cages housed mice that incurred severe fight wounds requiring both separation and euthanasia. In comparison, a 0% (0 of 16 cages) prevalence of fighting was observed among castrated male mice. Castration eradicated pain and distress associated with fighting, thereby constituting a refinement, and allowed the use of male mice from the breeding colony for surveillance, thereby reducing the total number of mice bred for surveillance. In conclusion, castration is a minimally invasive, safe, humane, rapid method to eliminate conspecific aggression among male CD1 surveillance mice.Our institution maintains SPF rodent facilities, and maintaining this status is critical, given that most infectious agents are known to affect research results and reliability. In addition, pathogen elimination efforts are difficult, expensive, and laborious. Because many murine pathogens cause no gross clinical signs in infected animals, ‘sentinel’ animals are used to detect the presence of these microbial agents. To ensure that colonies remain free of specified pathogens, all of the rodent facilities at our institution support an active surveillance program. In each mouse holding room, 6 sentinel CD1 mice are housed in a rat cage and, in an organized rotation, are exposed to dirty bedding from colony mice in that room. The sentinels are sampled for endo- and ectoparasites and undergo serologic analysis for viral agents and mycoplasma every 2 mo. In addition, bacteriology and histology of tissue samples are performed every 6 mo.Concurrently, CD1 mice are bred inhouse for the transgenic core facility and to supply mice for this sentinel program. Female pups are used as recipients for embryo transfer, are cycled back into the breeding program, or are introduced into the surveillance program. Traditionally, additional female CD1 mice were ordered from vendors to meet the numbers required for the surveillance program. As a refinement initiative, the male CD1 mice bred inhouse, which would otherwise be euthanized due to their lack of prescribed use, were integrated into the surveillance program. However, this practice had an unfortunate sequela: the male surveillance mice had a high prevalence of intracage aggression, often necessitating separation or euthanasia of affected mice. In addition to being a significant animal welfare concern, chronic social stress has known immunosuppressant effects that may be counterproductive to specific and sensitive serologic screening.5,11,12In addressing this welfare concern, we reviewed the numerous factors reported to influence aggression in adult male mice. These factors include stocking density, cage space, enrichment, cagemate familiarity, olfactory cues, and the influence of sex hormones.9,20,22,25,31 After carefully weighing each of these factors, we determined that stocking density, cage space, and enrichment had been optimized for both animal welfare and achieving the goals of the surveillance program. Littermates designated for the surveillance program were maintained as a group, therefore cagemates were familiar. However, sentinel mice were unavoidably exposed to exogenous olfactory cues from dirty bedding from multiple cages.20,22 We hypothesized that early castration could eliminate fighting in the male CD1 sentinels and concurrently support the needs and goals of the health monitoring program.  相似文献   
155.
Sixty five patients who had undergone surgery for parotid tumours over a period of nine years were studied retrospectively. There were 45 males and 20 females. There were 49 benign and 16 malignant tumours. Age ranged 35-69 years; mean 47 years. Pain (6%) and facial palsy (3%) were unusual features. Size of tumour at presentation varied from 1.5 to 12 cm. Superficial parotidectomy was the commonest operation performed and Total/Radical/Extended parotidectomy was done in selected cases. Postoperative radiotherapy was used in six cases. No recurrences were noted following surgery for benign tumours. However a local recurrence rate of 37% was found for malignancies (6/16 cases). This paper aims to review the experience of managing these tumours in the setting of service hospitals.KEY WORDS: Carcinoma parotid, Parotid tumour, Pleomorphic adenoma  相似文献   
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159.
Total body irradiation (TBI) is a highly emetogenic component of the majority of conditioning regimens in use for bone marrow transplantation. Conventional antiemetic therapy fails to control nausea and vomiting induced by single fraction TBI in as many as 50% of patients. In a double blind study of 20 patients undergoing marrow transplantation, a single 8 mg ondansetron dose was compared with placebo given immediately prior to TBI. Our routine premedication of phenobarbitone and corticosteroid was also administered to all patients. All patients had received high dose melphalan the previous evening. Only 1 of the 10 patients in the ondansetron group experienced an emetic event compared with 5 of the 10 in the comparison group (p = 0.029). No significant adverse events were observed. Ondansetron appears to have extremely useful antiemetic activity during single fraction low dose rate TBI.  相似文献   
160.
本文用ANS和DPH为荧光探剂,研究苯巴比妥(PB)诱导下大鼠肝微粒体膜脂区流动性与膜药酶活性变化的相关性。结果表明,经PB诱导后在增加肝微粒体蛋白质含量,P-450含量及NADPH-细胞色素C还原酶等酶活性的同时,肝微粒体膜流动性明显增大,且膜深层流动性的增大与膜氨基比林N-脱甲基酶、细胞色素C还原酶活性增加有明显的直线正相关。膜胆固醇/碑脂比值明显降低。此结果提示,肝微粒体膜流动性的适当增大与PB增加单胺氧化酶系统活性之间可能存在着某种联系。  相似文献   
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