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71.
目的探讨利用人UroplakinⅡ(hUPⅡ)启动子进行靶向性基因治疗膀胱癌的可能性。方法将hUPⅡ启动子和肿瘤坏死因子-α(TNF-α)克隆到腺病毒载体Ad5中,构建重组体pAd-hUPⅡ-TNF。转染细胞293后产生复制缺陷型的重组腺病毒,感染膀胱癌细胞系BIU-87,检测TNF-α对BIU-87细胞体外生物学行为及体内成瘤性的影响。结果成功构建pAd-hUPⅡ-TNF重组腺病毒载体,转染细胞293获得复制缺陷型重组腺病毒。BIU-87细胞经重组腺病毒感染后可产生高浓度的TNF-α,并降低BIU-87的生长速度。感染腺病毒的BIU-87培养液可抑制L929细胞的生长。裸鼠原位膀胱肿瘤动物模型实验结果表明膀胱灌注重组腺病毒48h后,裸鼠尿液含高浓度的TNF-α,4周后腺病毒组膀胱重量和体积明显低于对照组(P<0.01)。结论hUPⅡ启动子TNF-α为治疗基因的重组腺病毒可特异性使膀胱癌细胞系BIU-87产生高浓度的TNF-α,并降低BIU-87和L929细胞的生长速度。重组腺病毒可使裸鼠尿内含高浓度的TNF-α,并可抑制裸鼠原位膀胱肿瘤动物模型膀胱癌细胞的成瘤性。 相似文献
72.
S. Vitko Z. Wlodarczyk L. Kyllönen Z. Czajkowski R. Margreiter L. Backman F. Perner P. Rigotti B. Jaques D. Abramowicz M. Kessler J. Sanchez-Plumed L. Rostaing R.S. Rodger D. Donati Y. Vanrenterghem 《American journal of transplantation》2006,6(3):531-538
Tacrolimus combined with mycophenolate mofetil (MMF) is an effective regimen in kidney transplantation. This study compared the efficacy of combining tacrolimus and two different dosages of sirolimus with an established tacrolimus-MMF regimen. Each day in addition to tacrolimus, 325 patients received 2 mg sirolimus (TAC-SRL2 mg), 325 patients received 0.5 mg sirolimus (TAC-SRL0.5 mg) and 327 patients 1 g MMF (TAC-MMF). The initial tacrolimus dose was 0.2 mg/kg/day. Sirolimus patients received loading doses of 6 or 1.5 mg, and daily doses of 2 or 0.5 mg thereafter. Steroid administration was identical for all groups. The incidence of biopsy-proven acute rejection was lower in the TAC-SRL2 mg group (15.7%) compared with the TAC-SRL0.5 mg (25.2%, p = 0.003) and the TAC-MMF groups (22.3%, p = 0.036). Six-month graft survival was 91.0% (TAC-SRL2 mg), 92.6% (TAC-SRL0.5 mg) and 92.4% (TAC-MMF); the respective values for patient survival were 98.1%, 97.8% and 97.9%. Thirty-four patients (10.5%), 19 patients (5.8%) and 16 patients (4.9%) in the TAC-SRL2 mg, TAC-SRL0.5 mg and TAC-MMF groups, respectively, discontinued the study because of adverse events. Hyperlipemia was reported more often in the TAC-SRL2 mg group (24.0%) compared with 19.4% (TAC-SRL0.5 mg) and 11.0% (TAC-MMF; p < 0.05). Combining 2 mg sirolimus/day with tacrolimus results in lower rates of acute rejection, but a higher incidence of adverse events. 相似文献
73.
目的探讨衰老对大鼠阴茎组织结构、NO(nitric oxide)-cGMP(cvclic Guanosine Monophosphate)通路及端粒酶活性的影响作用。方法本课题以不同月龄大鼠阴茎组织及培养的平滑肌细胞为研究对象,检测不同月龄大鼠阴茎组织中NO量、NOS(Nitric Oxide Synthase)活性、cGMP量、端粒酶活性及海绵体结构的变化,并比较大鼠、人阴茎组织及大鼠原代海绵体平滑肌细胞的端粒酶活性。结果(1)大鼠阴茎组织中NO量、NOS活性均先升高后降低,各月龄组间有显著差异。阴茎组织cGMP含量逐渐降低,各月龄组间差别显著;(2)随龄增加,平滑肌纤维逐渐减少,胶原纤维增多,粗大成团,窦状隙变少、变窄:(3)大鼠阴茎组织端粒酶活性以2月龄活性最高,随龄增加逐渐下降。人阴茎组织中无端粒酶活性。结论(1)衰老对大鼠阴茎组织结构、NO.cGMP通路及端粒酶活性有显著影响,提示衰老与ED关系密切;(2)大鼠阴茎组织有端粒酶活性,可作为研究细胞衰老与ED关系有关端粒酶的模型。 相似文献
74.
75.
76.
庆大霉素对豚鼠前庭上皮IGF-1及其受体表达的影响 总被引:1,自引:0,他引:1
目的:研究庆大霉素对豚鼠前庭上皮胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)及其受体(insulin-like growth factor-1 receptor,EGF-1R)表达的影响,并探讨其生物学特性。方法:采用免疫组织细胞化学方法,以抗IGF-1及IGF-1R抗体为标记物,检测庆大霉素损伤后豚鼠前庭上皮自发修复期IGF-1及IGF-1R的表达变化和分布特点;采用Brdu体内标记和抗Brdu抗体免疫组化染色,检测庆大霉素损伤后豚鼠前庭上皮增殖的变化。结果:IGF-1及IGF-1R在正常成年豚鼠前庭上皮细胞中有低水平表达,庆大霉素损伤后,其表达增多。在1d组IGF-1及IGF-1R表达最强,其后逐渐减少。在正常对照组中无Brdu阳性细胞。各实验组均观察到Brdu阳性细胞,7d组最多。结论:庆大霉素损伤后,豚鼠前庭上皮IGF-1及IGF-1R表达增强,其时程变化与细胞增殖活动密切相关。IGF-1在豚鼠前庭上皮损伤后的细胞增殖中可能起重要信号转导作用。 相似文献
77.
78.
Chromogenic ionophore-based methods for spectrophotometric assay of sodium and potassium in serum and plasma 总被引:1,自引:0,他引:1
A Kumar E Chapoteau B P Czech C R Gebauer M Z Chimenti O Raimondo 《Clinical chemistry》1988,34(9):1709-1712
We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers. 相似文献
79.
J C Strainer J L Ulmer F Z Yetkin V M Haughton D L Daniels S J Millen 《AJNR. American journal of neuroradiology》1997,18(4):601
PURPOSETo use functional MR imaging to measure the effect of frequency (pitch), intensity (loudness), and complexity of auditory stimuli on activation in the primary and secondary auditory cortexes.METHODSMultiplanar echo-planar images were acquired in healthy subjects with normal hearing to whom auditory stimuli were presented intermittently. Functional images were processed from the echo-planar images with conventional postprocessing methods. The stimuli included pure tones with a single frequency and intensity, pure tones with the frequency stepped between 1,000, 2,000, 3,000, or 4,000 Hz, and spoken text. The pixels activated by each task in the transverse temporal gyrus (TTG) and the auditory association areas were tabulated.RESULTSThe pure tone task activated the TTG. The 1,000-Hz tone activated significantly more pixels in the TTG than did the 4,000-Hz tone. The 4,000-Hz tone activated pixels primarily in the medial TTG, whereas the 1,000-Hz tone activated more pixels in the lateral TTG. Higher intensity tones activated significantly more pixels than did lower intensity tones at the same frequency. The stepped tones activated more pixels than the pure tones, but the difference was not significant. The text task produced significantly more activation than did the pure tones in the TTG and in the auditory association areas. The more complex tasks (stepped tones and listening to text) tended to activate more pixels in the left hemisphere than in the right, whereas the simpler tasks activated similar numbers of pixels in each hemisphere.CONCLUSIONAuditory stimuli activate the TTG and the association areas. Activation in the primary auditory cortex depends on frequency, intensity, and complexity of the auditory stimulus. Activation of the auditory association areas requires more complex auditory stimuli, such as the stepped tone task or text reading. 相似文献
80.
B超引导下经皮肺穿刺针吸活检对周围型肺肿块的诊断价值 总被引:1,自引:0,他引:1
目的探讨B超引导下经皮肺穿刺针吸活检对周围型肺肿块的诊断价值。方法对31例患者施行B超引导肺穿刺针吸活检56次,进行细胞学和细菌学检查。结果穿刺取材成功率为93.6%,所获细胞学资料与手术病理诊断或临床治疗随访对照,定性诊断符合率为89.7%。结论该诊断方法简便实用,并发症轻微,适于临床推广应用。 相似文献