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141.
142.
Synthesis and release of 5-fluorouracil from poly(N-vinylpyrrolidinone) bearing 5-fluorouracil derivatives. 总被引:3,自引:0,他引:3
1-beta-allyloxycarbonyloxymethyl-5-fluorouracil (4) and 1,3-bis(beta-allyloxycarbonyloxymethyl)-5-fluorouracil (5) were synthesised by reacting 5-fluorouracil with formaldehyde followed by treating the product with isopropenyl chloroformate. The monomers 4 and 5 were copolymerized separately with N-vinylpyrrolidinone to form linear copolymers and cross-linked polymer networks, respectively. The monomer reactivity ratios in the copolymerization of 4 with NVP were evaluated by both linear and non-linear methods and the effect of monomer feed composition on copolymer molecular weight was examined. The degradation of the polymer networks in phosphate buffer (pH 7.4) was investigated. The hydrolytic scission of the carbonate groups resulted in release of 5-fluorouracil and a decrease in cross-linking density. The time-dependent fractional release of the 5-FU could be fitted by a power relationship with exponents between 0.10 and 0.25. 相似文献
143.
144.
伽玛刀治疗垂体大腺瘤临床分析(附30例报告) 总被引:2,自引:0,他引:2
目的 研究伽玛刀治疗垂体大腺瘤的效果及影响疗效的因素。方法 30例垂体大腺瘤病人用1.0T磁共振定位,Gamma-plan计划系统规划,等剂量曲线45%~60%(平均49.7%),周边剂量12~35Gy(平均22.9Gy),中心剂量24~70Gy(平均45.4Gy).Leksell伽玛刀实施放射外科治疗。分析治疗后垂体大腺瘤病例,总结其疗效和影响疗效的因素。结果 随访12~60个月,平均28个月,肿瘤完全消失6例(20%),肿瘤缩小19例(63.3%),无变化5例(16.7%);19/20(95.5%)功能性垂体腺瘤内分泌症状改善,临床症状好转,1例过早绝经(年龄36岁);5/10(50%)无功能性垂体腺瘤体积缩小.症状改善。结论 伽玛刀对于垂体大腺瘤仍是一种有效的治疗方法,其疗神与腺瘤的举类型、体积、照射剂量、剂量体剂、MRI信号特征密切相姜。 相似文献
145.
目的 探讨 1990~ 2 0 0 3年住院病人的主要病因和死因及变化趋势的方向、强度。方法 分析我院 1990~ 2 0 0 3年录入广东省卫生厅“广东省医院统计病案管理系统”的统计资料 ,计算住院病人主要疾病、死亡病因 1990~ 1999年、2 0 0 0~ 2 0 0 3年两个阶段的年均构成比 ,观察顺位变化 ,用回归分析的方法计算变化趋势。结果 1) 1990~ 1999年主要住院病因顺位是消化系统疾病 (15 .6 2 % )、损伤和中毒 (13.16 % )、循环系统疾病 (11.2 4 % )、呼吸系统疾病 (10 .4 7% )、恶性肿瘤 (10 .4 3% ) ;2 0 0 0~ 2 0 0 3年顺位是循环系统疾病 (16 .4 1% ) (其中缺血性心脏病占 2 2 .98% ,脑血管病占 39.6 8% ) ,损伤和中毒(12 .80 % )、消化系统疾病 (11.76 % )、呼吸系统疾病 (9.5 3% )、恶性肿瘤 (8.73% ) ,循环系统疾病呈显著上升趋势 (B =4 .2 6 ,P <0 .0 5 ) ,消化系统疾病呈显著下降趋势 (B =- 3.17,P <0 .0 5 ) ;2 ) 1990~ 2 0 0 3年住院死因顺位为恶性肿瘤 (2 9.2 9% )、循环系统疾病 (2 5 .91% )、损伤和中毒 (12 .6 3% )、呼吸系统疾病(6 .18% ) ,消化系统疾病 (5 .77% ) ;2 0 0 0~ 2 0 0 3年恶性肿瘤呈显著下降趋势 (B =- 3.88,P <0 .0 5 ) ,循环系统疾病呈上升趋势但无显著性 (B =0 .84 ,P >0 相似文献
146.
肝炎病毒标志物的检测对病毒性肝炎的临床诊断、治疗、分析、判断肝炎病毒感染者病程及传染性均有重要意义 ,本文就常用肝炎病毒标志物的临床意义研究进展作一简要介绍。1 甲型肝炎病毒标志物1.1抗 HAV IgM 抗 HAV IgM于发病后数天即出现 ,持续最短 30天 ,最长可达 14个月 相似文献
147.
148.
Stenotrophomonas maltophilia bacteremia in adults: four years' experience in a medical center in northern Taiwan. 总被引:1,自引:0,他引:1
Wei-Sheng Wang Chang-Pan Liu Chun-Ming Lee Fu-Yuan Huang 《Journal of microbiology, immunology, and infection》2004,37(6):359-365
Stenotrophomonas maltophilia has become an important nosocomial pathogen in immunocompromised patients in Taiwan. Patients with underlying diseases such as diabetes, uremia, and solid malignancy are extremely vulnerable to this organism. S. maltophilia bacteremia has a mortality rate of up to 62% if appropriate antibiotics are not instituted early. Knowledge of the risk factors for infection as well as local susceptibility patterns is helpful in determining which patients should receive empirical antibiotics active against S. maltophilia. This study assessed the characteristics of 50 episodes of S. maltophilia bacteremia in 48 patients admitted between March 3, 1999 and May 21, 2003. The new fluoroquinolone levofloxacin showed promising in vitro activity against S. maltophilia in view of the increasing resistance of isolates to trimethoprim-sulfamethoxazole. For patients at risk for S. maltophilia infection, such as those receiving mechanical ventilation in the ICU or those with multiple vascular access devices, the need for antimicrobial agents to which S. maltophilia is normally sensitive should be considered in selecting empiric therapy. 相似文献
149.
BACKGROUND: At present, researches on differentiating from human adipose-derived adult stromal cells (hADASC) to neuron-like cells are focus on inducing by artificial-synthetic compound solution; however, hippocampal astrocyte conditioned medium (HCAM) can induce in vitro differentiation from hADASC to neuron-like cells is still unclear.
OBJECTIVE: To observe whether HCAM can induce in vitro differentiation from hADASC to neuron-like cells.
DESIGN: Randomized control study.
SETTING: Department of Neurology, Taixing People's Hospital; Central Laboratory, North China Coal Medical College.
MATERIALS: Donor of adipose tissue was donated by female volunteers suffering from caesarean section in the department of obstetrics & gynecology in our hospital and aged 20-35 years. Adipose tissue was collected from subcutaneous tissue of abdomen during the operation. In addition, 8 male newborn Wistar rats within 24 hours with average body mass of 20 g were provided by Animal Institute of Chinese Academy of Medical Sciences. Rabbit-anti-human Nestin polyclonal antibody, rabbit-anti-human glial fibriliary acidic protein (GFAP) polyclonal antibody, rabbit-anti-human neuro-specific enolase polyclonal antibody and mouse-anti-human microtubal associated protein 2 (MAP-2) polyclonal antibody were provided by Wuhan Boster Company.
METHODS: The experiment was carried out in the Central Laboratory of North China Coal Medical College from October 2004 to June 2005. hADASC was cultured with HCAM and its growth and morphological changes were observed under inverted phase contrast microscope. Immunocytochemistry, immunofluorescence and Western blotting were used to evaluate the expressions of Nestin, which was a specific sign of nerve precursor, neuro-specific enolase and MAP-2, which was a specific sign of nerve cell, and GFAP, which was a specific sign of neuroglial cells.
MAIN OUTCOME MEASURES: Nestin, which was a specific sign of nerve precursor, neuro-specific enolase and MAP-2, which was a specific sign of nerve cell, and GFAP, which was a specific sign of neuroglial cells.
RESULTS: On the 3rd day of culture, partial hADASC started deformation from slender shuttle-shape cells to neuron-like cells. It suggested that cells stretched out apophysis, which were mainly double-pole or multiple-pole cells. Five days later, immunohistochemical detection suggested that expression of Nestin (10.5±0.037) was found out in cells; meanwhile, expressions of GFAP (38.4±0.052) and neuro-specific enolase (NSE) (15.7±0.023) were also found out in cells; however, expression of MAP-2 was not observed. Western blot indicated that, 5 days after effect of HCAM, Nestin was found out in hADASC; meanwhile, expressions of GFAP and neuro-specific enolase were also found out; however, expression of MAP-2 was not observed.
CONCLUSION: HCAM can induce the differentiation from hADASC to neuron-like cells in vitro. 相似文献
150.
鼓室穿刺治疗腭裂渗出性中耳炎的临床评价 总被引:1,自引:0,他引:1
目的 探讨腭裂修复同期 ,鼓室穿刺对腭裂伴分泌性中耳炎患者中耳功能及听力损失的影响。方法 将 80例 ( 14 6耳 )患有分泌性中耳炎的腭裂患者 ,随机分为实验组 ( 78耳 ) :常规腭裂修复术 ,术毕作鼓室穿刺。对照组 ( 68耳 ) :单纯腭裂修复术。术后 6个月两组均进行鼓室图、脑干听觉诱发电位检查 ,并进行比较。结果 实验组术后无论与术前比较 ,还是与对照组术后比较 ,鼓室图、V波反应阈值及轻、中度听力损失 ,均有显著进步 (P <0 0 1) ;术后半年内实验组听力恢复早 ,而且治愈率高 ( 96 2 % ,75 /78) ,明显优于对照组 ( 3 8 2 % ,2 6/68)。结论 腭裂修复同期鼓室穿刺 ,不仅有助于改善伴有分泌性中耳炎腭裂患者的中耳功能 ,提高听力 ;而且可避免或减少粘连性中耳炎的发生 相似文献