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61.
The role of mtDNA deletion in the sensitivity to aminoglycoside antibiotic induced deafness] 总被引:2,自引:0,他引:2
OBJECTIVE: To establish an animal model of mitochondrial DNA (mtDNA) deletion and investigate the possible role of mtDNA deletion in aminoglycoside antibiotic induced deafness. METHODS: Thirty wistar rats (4 months) were randomly divided into group A and B. Doxorubicin (DOX) was subcutaneously injected at doses of 2 mg/kg twice per week for 3 months in group A and then kanamycin (KM) was intraperitoneally injected 500 mg/kg per day for 10 consecutive days. The treatments of group B were identical to group A, except normal saline was substituted for DOX. The thresholds of auditory brainstem response (ABR) were measured before and after the drug administrations. The inner ear membranous labyrinthine tissue was harvested and mtDNA was amplified to identify 4,834 bp deletion by PCR technique. RESULTS: The elevation of the mean ABR thresholds in group A(67.08 +/- 8.59) dB peSPL was significantly higher than that in group B (12.71 +/- 4.42) dB peSPL after KM administration (P < 0.001). In group A, 9 of the 15 rats demonstrated 4,834 bp mtDNA deletion. However, mtDNA 4,834 bp deletion was negative in group B animals. CONCLUSION: DOX can induce mtDNA deletion in the inner ear tissue of the rat. mtDNA deletion in the inner ear may play an important role in the hypersensitivity to aminoglycoside antibiotic ototoxicity. 相似文献
62.
63.
铅对大鼠肠道神经元和血管平滑肌细胞NOS活性的影响 总被引:12,自引:0,他引:12
用β-NADPH组织化学方法研究铅对大鼠肠壁肌间神经佾内神经元和血管平滑肌一氧化氮合酶(NOS)活性的影响。结果发现:腹腔注射醋酸铅(40mg.kg^-1)15d后,大鼠肠道NOS阳性神经无元和阳性纤维数量减少,且阳性神经元的形态也有不同程度的改变,肠壁内血管平滑肌NOS活性下降。上述变化提示NO的生成减少可能是铅中毒时腹能的机制之一。 相似文献
64.
Twenty seven plant extracts were selected on the basis of ancient literature search for rheumatoid arthritis or similar syndrome. Methanol extract of each plant was prepared and administered orally to rats everyday at a dose of 200 mg/kg/day. Experimental arthritis was induced by subplantar injection of heat-killedMycobacterium butyricum to right hind paw of rats. This treatment provoked swelling of the treated paw in two phases, acute primary swelling and secondary arthritic swelling. An inhibition of secondary swelling was considered to be antiarthritic activity. Several plant methanol extracts such asAkebia quinata (caulis),Ephedra sinica (herba) andSophorae subprostrata (radix) were found to show significant inhibitory activity against secondary swelling at the dose tested. Our results strongly suggested an antiarthritic potential of these plant extracts. 相似文献
65.
66.
目的:探讨退变性腰椎管狭窄症的手术治疗。方法:对94例60岁以上患者进行分型和手术治疗。结果:将本病分为Ⅰ型(侧隐窝狭窄型);Ⅱ型(中央管狭窄型);Ⅲ型(混合型)。对Ⅰ型手术方式采用单侧或双侧椎板开窗,扩大神经根管或(和)摘除髓核;对Ⅱ型行半椎板或全椎板切除术;对Ⅲ型行全椎板切除术。结论:通过术后疗效观察和3年随访,根据分型的不同选择不同的手术方式,可达到较好的临床疗效 相似文献
67.
The authors examined potential associations between air-pollution exposures and respiratory symptoms and illnesses of 4,108 adults who resided in 4 districts of 3 large, distinct Chinese cities. Data on respiratory health outcomes and relevant risk factors for parents and children were obtained via standardized questionnaires in the winter of 1988. (The effects in children were described previously.) The yearly averages of ambient levels of total suspended particles in the 4 districts for the years 1985-1988 differed greatly. The authors constructed logistic-regression models to assess the respiratory health parameters of parents of the children. The results revealed significant and strong effects, by district, on prevalence rates of cough, phlegm, persistent cough and phlegm, and wheeze for both the mothers and the fathers. In addition, the odds ratios increased as ambient total suspended particle concentration increased across the 3 urban districts. Other local within-city risk factors, however, may have confounded the total suspended particles-effects association, especially for asthma prevalence. Findings for adults were similar to those found for their children. A strong adverse effect of active tobacco smoking on the fathers' respiratory health was observed. The children appeared to be more strongly affected by passive smoking exposure received in their homes than their mothers. 相似文献
68.
K A Schulman K R Yabroff J Kong K F Gold L E Rubenstein A J Epstein H Glick 《Health services research》1999,34(2):603-621
OBJECTIVE: To utilize health services research techniques in developing an episode of care using an administrative data set. This method is demonstrated for an episodic clinical condition, migraine. DATA SOURCES: Medicaid administrative data set of 3,372 patients with a diagnosis of migraine (ICD-9-CM 346.0, 346.1) in the state of Pennsylvania between May 1990 and March 1992. STUDY DESIGN: The duration of a migraine episode was measured by assessing the magnitude of resource utilization and the proportion of patients with charges in the period after the index migraine as compared to the period before the index migraine. A confidence interval (CI) was developed around each measure using bootstrap techniques. DATA COLLECTION METHODS: All charge data were extracted daily for a 113-day observation period surrounding each index migraine in order to observe the duration of impact of a migraine diagnosis on resource utilization. PRINCIPAL FINDINGS: The lower limits of both the 95% and 99% CIs for the difference in charges are greater than 0 for three weeks. The lower limits of both CIs for the difference in the proportion of patients with charges are above 0 for six weeks. CONCLUSIONS: Our analysis demonstrates that a health services research framework can be used to define an episode of care for a chronic disease category such as migraine. This method can be used to evaluate episodes of care for clinical studies of limited or episodic conditions and to complement clinical expertise in developing time horizons for clinical trials. 相似文献
69.
慢性肾功能衰竭中医证型标准化研究探讨 总被引:21,自引:0,他引:21
本文对2次全国性慢性肾衰中医辨证分型标准进行了分析和总结,并按现行慢性肾衰辨证分型方案对444例患者进行证候学研究,列出了慢性肾衰中出现率高且具有鉴别诊断价值的症状及体征,并发现慢性肾衰尿毒症患者其气血阴阳虚损的积分值明显高于其它各期,提出现行方案的不足之处及有待改进的探讨意见 相似文献
70.
对某化纤厂99名长期接触低浓度二硫化碳(CS2)作业工人和28名同厂非CS2作业工人的血脂进行流行病学横断面调查。结果发现:除接触组脂蛋白(a)[Lp(a)]浓度明显高于对照组外,其它血脂指标差别均无统计学意义;进一步通过多元逐步回归分析发现,长期低浓度CS2接触对Lp(a)的影响最大,二者呈正相关(r=0.43,P<0.01)。提示Lp(a)可能在CS2致脂质代谢障碍毒作用机制中起着重要作用。 相似文献