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991.
胃复宁对大鼠胃黏膜异型增生的预防及对P^53、P^21蛋白表达调节的影响 总被引:1,自引:0,他引:1
目的观察胃复宁对实验大鼠CAG伴DYS的预防作用和对P^53、P^21基因蛋白表达的干预作用。方法胃炎组用去氧胆酸钠联合无水乙醇制造大鼠CAG伴DYS的实验模型;胃复宁组在胃炎组造模的基础上再施予不同剂量的胃复宁,以观察胃复宁对大鼠CAG伴DYS的防预效果,同时检测P^53、P^21蛋白表达率。比较胃炎组、胃复宁组、果胶铋组和空白对照组之间CAG伴DYS的发生率和P^53、P^21基因蛋白的表达情况。结果胃炎组CAG的发生率为100%,DYS发生率为83%;胃复宁(高、中剂量)组CAG的发生率为13%~20%,DYS发生率仅为6.6%~13%;两组比较有显著的差异(P〈0.01)。胃炎组P^53蛋白阳性表达率为58.33%,胃复宁(高、中剂量)组P^21蛋白阳性表达率为20%~26%,两组比较有显著的差异(P〈0.01)。胃炎组P^21蛋白阳性表达率为50.00%,胃复宁(高、中剂量)组P^21蛋白的表达为13%~26%,两组比较有显著的差异(P〈0.01)。结论胃复宁(高、中剂量)组通过干预P^21、P^53基因蛋白的表达,防止了细胞过度增生和癌变,有效防治大鼠CAG的形成,抑制胃上皮DYS的发生,降低了CAG伴DYS发展为胃癌的危险性。 相似文献
992.
芒果甙诱导鼻咽癌CNE2细胞凋亡及其对细胞内钙含量的影响 总被引:5,自引:0,他引:5
目的研究芒果甙在体外对人鼻咽癌细胞系CNE2细胞凋亡和细胞内钙离子(IECa^2+)含量的影响。方法采用流式细胞术检测不同浓度芒果甙作用24、48、72h后诱导CNE2细胞凋亡和IECa^2+含量的影响。结果(1)芒果甙作用24、48、72h后,不同浓度的芒果甙均可诱导CNE2细胞凋亡,随着芒果甙浓度的升高和作用时间的延长而增高;(2)不同浓度芒果甙作用24、48、72h后,CNE2细胞内IECa^2+含量显著上升,且随着芒果甙浓度的升高和作用时间的延长而增高。结论芒果甙能显著诱导CNE2细胞凋亡;CNE2细胞内IECa^2+含量的升高在芒果甙诱导CNE2细胞凋亡中起到重要作用。 相似文献
993.
994.
百合知母汤对自然衰老型围绝经期综合征肾虚证大鼠中枢神经递质含量的影响 总被引:1,自引:0,他引:1
目的:观察百合知母汤(BHZMT)对自然衰老型围绝经期综合征肾虚证大鼠脑内中枢神经递质含量的影响.方法:采用自然衰老雌性15~16月龄SD大鼠,随机分为:围绝经期组、围绝经期+BHZMT组、围绝经期+TX肾阴虚组、围绝经期+TX+BHZMT组、围绝经期+ADE肾阳虚组、围绝经期+ADE+BHZMT组,另设一青年对照组共7组,造模1周后,各组连续灌胃给予BHZMT 3周.于末次给药次日,脱颈椎处死大鼠,迅速分离下丘脑,分别采用高效液相色谱--电化学方法测定单胺类神经递质NE、DA、5-HT的含量和免疫组化方法测定P物质和β-内啡肽的含量.结果:围绝经期大鼠NE、β-内啡肽水平下降,DA、5-HT、P物质水平明显升高;肾阴虚证大鼠NE、DA、5-HT、P物质水平明显升高,β-内啡肽则明显减少;肾阳虚证大鼠5-HT水平明显升高;经BHZMT治疗后,肾阴虚大鼠下丘脑NE、DA、5-HT(P<0.01)、P物质的含量降低,β-内啡肽的含量升高;肾阳虚大鼠下丘脑NE、DA含量升高,5-HT水平降低,但无显著性差异.结论:BHZMT可有效调节围绝经期肾阴虚大鼠脑内中枢神经递质含量,从而改善围绝经期综合征. 相似文献
995.
复方贞术调脂胶囊对大鼠非酒精性脂肪肝的影响 总被引:2,自引:2,他引:0
目的探讨复方贞术调脂胶囊对大鼠非酒精性脂肪肝的影响,为其临床用药提供依据。方法取SD大鼠60只,随机分成正常组、模型组、复方贞术调脂胶囊高、中、低组、非诺贝特组。除正常组外,其他组采用高脂乳剂灌胃复制大鼠非酒精性脂肪肝模型,造模同时复方贞术调脂胶囊高、中、低组、非诺贝特组连续给药8周后,测定肝脏胆固醇(TC)、三酰甘油(TG),并计算肝指数,光镜下观察肝脏病理学变化。结果复方贞术调脂胶囊能降低肝脏TC和肝指数。肝脏病理切片结果显示复方贞术调脂胶囊组肝细胞脂肪变性、水样变性及坏死和炎症细胞浸润等病理表现均有所减轻,明显轻于模型组。结论复方贞术调脂胶囊对非酒精性脂肪肝有较好的防治作用。 相似文献
996.
Objective A promising radiopharmaceutical 99mTc-HYNIC-TOC (99mTc-HYNIC-Octreotide) can be applied for somatostatin receptor scintigraphy with the potential to replace Indium-111 labeled
somatostatin analogus. Here we evaluate whether orbital 99mTc-HYNIC-TOC scintigraphy can be used as a Graves’ ophthalmopathy (GO) activity parameter to predict the retrobulbar irradiation
response.
Methods Orbital 99mTc-HYNIC-TOC scintigraphy was performed on 14 consecutive patients demonstrating moderated to severe Graves’ ophthalmopathy.
The patients were treated with retrobulbar irradiation following the octreoscan and the response to this therapy was assessed
at 3 months after the start of treatment. The orbital 99mTc-HYNIC-TOC uptake was calculated to assess the effects of treatment.
Results Among the 14 GO patients, eight (57.1%) responded to retrobulbar radiotherapy; six (42.9%) showed no change. We compared the
eight responders and six non-responders in terms of orbital 99mTc-HYNIC-TOC uptake, using the orbital/occipital ratio. On the 4-h 99mTc-HYNIC-TOC scintigraphy, responders had a higher orbital/occipital uptake ratio than the no-responders (P = 0.001). A significant correlation was found between the orbital/occipital ratio and the clinical activity score (CAS) (P = 0.034). The Receiving-Operator-Characteristic curve showed the best threshold for discriminating active and inactive disease
was 1.40 (sensitivity, 100%; specificity, 83.3%). In the responders group, all these eight patients had positive scintigraphy.
While there were five patients who had negative scintigraphy in the non-responders group.
Conclusion Orbital 99mTc-HYNIC-TOC scintigraphy can be a useful method for the estimation of disease activity and prediction the response to subsequent
radiotherapy in GO patient. And the patients with positive octreoscan were more likely to respond to irradiation.
Hua Sun and Xu-Feng Jiang contribute equally to this article. 相似文献
997.
Influence of heme oxygenase-1 gene transfer on the viability and function of rat islets in in vitro culture 总被引:1,自引:0,他引:1
Chen XB Li YX Jiao Y Dong WP Li G Chen J Tan JM 《World journal of gastroenterology : WJG》2007,13(7):1053-1059
AIM: To investigate the influence of heme oxygenase-1 (HO-1) gene transfer on the viability and function of cultured rat islets in vitro. METHODS: Islets were isolated from the pancreata of Sprague-Dawley rats by intraductal collagenase digestion, and purified by discontinuous Ficoll density gradient centrifugation. Purified rat islets were transfected with adenoviral vectors containing human HO-1 gene (Ad-HO-1) or enhanced green fluorescent protein gene (Ad-EGFP), and then cultured for seven days. Transfection was confirmed by fluorescence microscopy and Western blot. Islet viability was evaluated by acridine orange/propidium iodide fluorescent staining. Glucose-stimulated insulin release was detected using insulin radioimmunoassay kits and was used to assess the function of islets. Stimulation index (SI) was calculated by dividing the insulin release upon high glucose stimulation by the insulin release upon low glucose stimulation. RESULTS: After seven days culture, the viability of cultured rat islets decreased significantly (92% +/- 6% vs 52% +/- 13%, P < 0.05), and glucose-stimulated insulin release also decreased significantly (6.47 +/- 0.55 mIU/L/30IEQ vs 4.57 +/- 0.40 mIU/L/30IEQ, 14.93 +/- 1.17 mIU/L/30IEQ vs 9.63 +/- 0.71 mIU/L/30IEQ, P < 0.05). Transfection of rat islets with adenoviral vectors at an MOI of 20 was efficient, and did not impair islet function. At 7 d post-transfection, the viability of Ad-HO-1 transfected islets was higher than that of control islets (71% +/- 15% vs 52% +/- 13%, P < 0.05). There was no significant difference in insulin release upon low glucose stimulation (2.8 mmol/L) among Ad-HO-1 transfected group, Ad-EGFP transfected group, and control group (P > 0.05), while when stimulated by high glucose (16.7 mmol/L) solution, insulin release in Ad-HO-1 transfected group was significantly higher than that in Ad-EGFP transfected group and control group, respectively (12.50 +/- 2.17 mIU/L/30IEQ vs 8.87 +/- 0.65 mIU/L/30IEQ; 12.50 +/- 2.17 mIU/L/30IEQ vs 9.63 +/- 0.71 mIU/L/30IEQ, P < 0.05). The SI of Ad-HO-1 transfected group was also significantly higher than that of Ad-EGFP transfected group and control group, respectively (2.21 +/- 0.02 vs 2.08 +/- 0.05; 2.21 +/- 0.02 vs 2.11 +/- 0.03, P < 0.05). CONCLUSION: The viability and function of rat islets decrease over time in in vitro culture, and heme oxygenase-1 gene transfer could improve the viability and function of cultured rat islets. 相似文献
998.
999.
Zhao Y Jiao J Shan Z Fan Q Hu J Zhang Q Zhu X 《The Thoracic and cardiovascular surgeon》2007,55(7):447-449
BACKGROUND: The purpose of the current study was to investigate the most effective diagnostic method and the effect of surgical treatment on traumatic main bronchial rupture. METHODS: Chest X-rays, CT and fiberoptic bronchoscopy were the main means used to confirm the diagnosis. Surgery was performed as early as possible. RESULTS: Pneumonectomy was performed in 1 patient. Bronchial end-to-end anastomosis was performed in 10 patients whose lungs were well ventilated, and lung function recovered. CONCLUSION: Main bronchial rupture occurs relatively rarely. Early diagnosis and operative intervention can save lives. 相似文献