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101.
目的 分析传代培养角膜细胞染色体数目的变异率.方法 选择人角膜上皮细胞(HCE)、牛角膜内皮细胞(BCE)和兔角膜上皮细胞(RCE)细胞,采用直接法制备传代细胞染色体标本,常规Giemsa染色,1 000倍光学显微镜下计数分裂相染色体数目,进行核型分析,统计染色体数目变异情况.结果 HCE染色体众数为56 ~ 65,为超二倍体;BCE染色体众数为27 ~ 34,为亚二倍体;RCE染色体众数为74 ~ 88,为超二倍体.与起源细胞相比,以上3种传代细胞染色体数目均发生了改变.结论 该项核型分析为HCE、BCE和RCE 的功能研究提供了重要的参考信息.  相似文献   
102.
红外光谱与计算机对比软件对不同生地黄的快速鉴别   总被引:6,自引:0,他引:6  
白雁  孙素琴  樊克锋  李军  王东  娄玉霞 《中药材》2005,28(4):281-284
目的:对野生和栽培生地黄及不同贮藏年限的生地黄(2000、2002年采收)以及"道地(河南)和非道地(其他省份)"生地黄药材进行快速鉴别研究.方法:利用傅里叶红外光谱技术(FT-IR)结合对比软件,并借助计算机运用归一化图谱辅助处理技术.结果:野生和栽培生地黄红外吸收光谱有明显的差异;对不同贮藏年限生地黄的识别率为100%;"道地和非道地"生地黄既有整体差异,又有个体交叉,识别率高于90%.结论:该方法具有快速、准确等特点.  相似文献   
103.
齐墩果酸对更年期大鼠作用的实验研究   总被引:11,自引:1,他引:11  
娄艳  陈志良  王春霞 《中药材》2005,28(7):584-587
目的:探讨齐墩果酸(Oleanolic acid)作为女贞子的主要成分在更年期综合症治疗中的独立性.方法:本实验分设更年期模型组、齐墩果酸组、大豆异黄酮组及青年鼠对照组,分别检测各组大鼠E2、MDA、SOD、GSH-Px水平,光镜观察卵巢、肾上腺皮质形态改变等指标,以评价齐墩果酸在更年期综合症治疗中的作用.结果:齐墩果酸能提高更年期鼠E2、SOD、GSH-Px水平(P<0.05),降低MDA(P<0.01)水平;改善卵巢及肾上腺的形态和功能.结论:齐墩果酸在治疗更年期综合症中能独立发挥作用.  相似文献   
104.
PURPOSE: The long-term survival of children between age 12 and 24 months with stage 4 neuroblastoma and nonamplified MYCN (MYCN-NA) has not been defined previously. PATIENTS AND METHODS: Survival for stage 4 MYCN-NA neuroblastoma patients enrolled onto Children's Cancer Group (CCG) protocols 321P2 (1986 to 1991) and 3891 (1991 to 1996) was analyzed. Treatment consisted of intensive alkylator-based induction chemotherapy with or without autologous bone marrow transplantation (ABMT) with or without 13 cis-retinoic acid. Survival was analyzed by age strata less than 12, 12 to 18, 18 to 24, and more than 24 months at diagnosis. Patients younger than 12 months were treated on the moderate-intensity CCG protocol 3881. RESULTS: Forty-three patients with stage 4 MYCN-NA disease enrolled onto CCG-321P2 (n = 17) or CCG-3891 (n = 26) were between 12 and 24 months of age at diagnosis. After a median follow-up of 94 months (range, 4 to 140 months), the 6-year event-free survival (EFS) for the 12- to 18-month age group was superior to that of the 18- to 24-month age group (74% +/- 8% v 31% +/- 12%; P = .008). The EFS for children older than 24 months with stage 4 MYCN-NA neuroblastoma was 23% +/- 3%, and for children younger than 12 months was 92% +/- 3%. CONCLUSION: Children diagnosed with stage 4 MYCN-NA neuroblastoma in the second year of life form a transitional group between infants and older children in terms of prognosis. Patients between 12 and 18 months of age have significantly better long-term survival than that of older children treated with intensive chemotherapy with or without ABMT. These patients may not benefit from additional intensification of therapy beyond that provided in earlier clinical trials and may even maintain this high survival rate with less intensive therapy.  相似文献   
105.
背景与目的:目前对海绵窦区肿瘤的手术治疗仍是神经外科的难题之一。本文旨在提高海绵窦区肿瘤的全切率,降低神经功能的残障率。方法:针对海绵窦外侧壁的显微解剖特点,结合典型病例分析,回顾性总结了9例海绵窦内肿瘤,经前外侧或外侧硬膜外入路,通过显微神经外科技术切开海绵窦外侧壁夹层,按神经走行方向切开,辨认肿瘤生长和颅神经的关系分块切除肿瘤。结果:9例海绵窦内肿瘤中,海绵状血管瘤1例,神经鞘瘤6例,脑膜瘤2例。全切除5例,3例次全切除,1例大部分切除。3例出现新的颅神经功能障碍症状,6个月后新出现的颅神经功能障碍症状减轻2例.完全恢复1例。结论:明确的海绵窦区显微外科解剖概念.娴熟的显微神经外科技术以及选择适当的手术入路是提高海绵窦区肿瘤的全切率,降低术中出血、术后残障率的关键因素。  相似文献   
106.
OBJECTIVE To study the synergistic effect of STI571, an inhibitor of tyrosine kinase, in combination with arsenic trioxide As2O3 on a multidrug-resistant leukemia cell line expressing bcr-abl.METHODS The cytotoxic effect of STI571 alone or in combination with different concentrations of As2O3 on the bcr-abl and mdr1 -positive leukemia cell line, K562-n/VCR, was examined by the MTT method.RESULTS One μmol/L of STI571 alone had no significant cytotoxic effect on K562-n/VCR cells. However the cytotoxic effect increased markedly when combined with As2O3 at concentrations of 10-5, 10-6, 10-7 and 10-8 mol/L. The IC50 of K562-n/VCR cells in As2O3 group was 1.879 μmol/L, with. Upon addition of STI571, the IC50 decreased to 0.155 μmol/L resulting in a synergistic cytotoxic effect on K562-n/VCR ceils that was increased 12.1 times.CONCLUSION A combination of STI571 with As2O3 has a more powerful inhibitory effect on leukemia cells expressing positive bcr-abl and positive mdrl compared to the effect with As2O3 alone.  相似文献   
107.
Abstract: Nuclear magnetic resonance (NMR) spectra of a model peptide (BL‐DIS6), in the presence of anticonvulsant diphenyl drug, phenytoin (DPH), were measured to obtain the interactions between the selected drug and the model peptide. BL‐DIS6's sequence corresponds to the S6 segment in domain I of rat brain type IIA Na+‐channel. NMR studies have demonstrated that the magnitude of the chemical shifts of amide‐ and α‐protons can be used as a measurement of the complex stability and binding site of the peptide. Our NMR results propose a 310‐helical structure for BL‐DIS6, and suggest a binding cavity for DPH that involves the hydrophobic particles of residues Ans‐7, Leu‐8, Val‐11, and Val‐12. Furthermore, molecular modeling was performed to provide a possible complex conformation that the phenyl portion of DPH is accommodated in the proximity of the C‐terminal residues Ala‐11 and Val‐12, and simultaneously the heterocyclic amine ring of DPH is perching at the residue Asn‐7 periphery and stabilizing the phenyl portion deep insertion into the peptide.  相似文献   
108.
2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a mutagenic and carcinogenic heterocyclic amine formed during ordinary cooking, and is subsequently metabolically activated by cytochrome P4501A2 (CYP1A2) and N-acetyltransferase 2 (NAT2). Respective genes encoding for these enzymes, display polymorphic distribution in the human population and are thus believed to cause interindividual differences in cancer risk susceptibility. The present study investigated the influence of dietary exposure and CYP1A2 and NAT2 genotypes and phenotypes on differential urinary PhIP excretion levels in 71 human volunteers after consumption of either a high (7.4 ng/g) or low (1.7 ng/g) dose of PhIP. Urinary PhIP excretion levels were found to reflect recent dietary exposure levels, with average levels of 174% (high dose group) and 127% (low dose group), as compared to pre-feed levels. Urinary caffeine metabolite ratios were significantly different between the two NAT2 genotypes, whereas for CYP1A2, the apparent difference in metabolic ratios between the genotypes was statistically non-significant. Significant correlations were firstly found between the CYP1A2-164A-->C (CYP1A2*1F) polymorphism and differential urinary PhIP excretion levels. Although the found correlations are driven primarily by a small number of subjects possessing the homozygous variant constellation, the strong influence of this genotype indicates that the CYP1A2*1F polymorphism could play an important role in human cancer risk susceptibility.  相似文献   
109.
Wei Du  Wei Lou  Qiang Wu 《国际眼科》2019,12(11):1788-1792
With the evolution of cataract surgery from visual rehabilitation to refractive surgery, aspheric intraocular lenses (IOLs) are being increasingly used in the field of ophthalmology. This increased use can be attributed to negative or zero spherical aberrations with unique optical designs, which counteract some of the positive spherical aberrations of the cornea. These alterations reduce the total spherical aberration of human eyes and improve the visual acuity in patients with cataract postoperatively. At present, various types of aspheric IOLs are used worldwide. Although the implantation of aspheric IOL is beneficial to the patients who need correction of spherical aberrations, much controversy is still associated with ocular residual spherical aberrations that facilitate the best visual quality for patients postoperatively. In order to provide reference for future clinical work and scientific research, this report reviews the relationship between the ocular residual spherical aberration of human eyes and visual quality.  相似文献   
110.
观察利用微信干预增加青光眼患者体力活动的效果。方法:前瞻性随机对照研究。选择2018年 6-12月于温州医科大学附属眼视光医院门诊确诊的青光眼患者102例作为研究对象。利用Excel生成的随机数随机分为对照组和干预组。对照组患者仅在门诊入组时进行运动宣教,并告知其可增加每天的运动步数;干预组患者入组时进行运动宣教,告知其可增加每天的运动步数的同时,加入微信群进行运动提醒干预。所有患者均需利用运动监测仪器完成基线1周和随访1个月的体力活动监测。采用卡方检验、独立样本t检验、Mann-Whitney U检验、配对t检验及Wilcoxon符号秩检验进行数据分析。结果:排除30例基线运动量较大(步数>12 000步/d)、依从性不好及其他原因失访的患者,最终纳入72例(对照组42例,干预组30例)。干预组患者干预后的步数(t=4.94,P<0.001),运动消耗的卡路里(Z=-2.87,P=0.004),代谢当量(Z=-3.30,P=0.001),中等强度体力活动时间(Z=-2.89, P=0.004),高强度体力活动时间(t=2.57,P=0.016)及中高强度体力活动时间(Z=-3.01,P=0.003)均较基线增加;轻度体力活动时间(t=-2.14,P=0.041)和久坐静止不动次数较干预前减少(t=-2.76, P=0.022)。对照组随访的步数也较基线增加(t=3.29,P<0.001),轻度体力活动时间较基线减少(t=-2.57,P=0.014)。另外,干预组的高强度体力活动时间增加量(随访-基线)(Z=-3.04,P=0.002)和超高强度体力活动时间增加量(Z=-2.06,P=0.040)明显高于对照组,差异均有统计学意义。结论:微信干预可以增加青光眼患者的每天运动步数和中高强度体力活动时间,减少患者的轻度体力活动时间和久坐静止次数。  相似文献   
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