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991.
AIM: To determine moxonidine in aqueous humor and iris-ciliary body by reversed-phase high performance liquid chromatography (RP-HPLC), and to evaluate the retinal neuroprotective effect after topical administration with moxonidine in a high intraocular pressure (IOP) model. METHODS: The eyes of albino rabbits were administered topically and ipsilaterally with 0.2% moxonidine. A RP-HPLC method was employed for the identification and quantification of moxonidine between 2 and 480min, which presented in the aqueous humor and iris-ciliary body. Flash electroretinography (F-ERG) amplitude and superoxide dismutase (SOD) level were measured between day 1 and day 15 after topical administration with moxonidine in a rabbit model of high IOP. Histological and ultrastructural observation underwent to analyze the changes of retinal morphology, the inner retinal layers (IRL) thickness, and retinal ganglion cell (RGC) counting. RESULTS: Moxonidine was detectable between 2 and 480min after administration, and the peak concentration developed both in the two tissues at 30min, 0.51 μg/mL in aqueous humor and 1.03 μg/g in iris-ciliary body. In comparison to control, F-ERG b-wave amplitude in moxonidine eyes were significantly differences between day 3 and day 15 (P<0.01) in the high IOP model; SOD levels were significantly higher at all time-points (P<0.01) with a maximum level of 20.29 U/mgprot at day 15; and RGCs were significantly higher (P<0.05). CONCLUSION: Moxonidine is a viable neuroprotective agent with application to high IOP model. All layers of retina, including RGC layer, retinal nerve fiber layer and INL, are more preserved after moxonidine administration. SOD plays a neuroprotective role in ocular hypertension-mediated RGC death.  相似文献   
992.
角膜曲率计与角膜地形图仪测量角膜屈光度的对比研究   总被引:3,自引:0,他引:3  
目的:对使用角膜曲率计与角膜地形图仪测量角膜屈光度的结果进行对比研究,提出两种仪器各自在白内障术前测算人工晶状体度数中提供K值的精确性。方法;在无眼表疾病的38例(76只眼)分别使用美国生产的角膜地形图仪和日本生产的角膜曲率计测量角膜屈光度,然后进行统计学处理。结果:角膜曲率计和角膜地形图仪检查结果略有差异,但经统计学处理无显著意义(P>0.05)。结论:角膜地形图仪系统测量角膜屈光度更为准确、全面,尤其对角膜过陡、过平、有斑翳、云翳者的检测结果更有参考价值。  相似文献   
993.

在间歇性外斜视患者的管理中,眼位控制力至关重要,它是评价手术时机的重要参考指标及监测和判断病情发展严重程度的必要指标之一。因此,眼位控制能力的量化成为间歇性外斜视评估中的重要环节。本文旨在对间歇性外斜视患者眼位控制力评估方法做一综述,帮助临床医生对间歇性外斜视患者制定合理的治疗方案。  相似文献   

994.
目的了解抵抗素在人眼眶脂肪组织及眼外肌组织中mRNA及蛋白表达情况。方法RT-PCR法检测人眼眶脂肪组织及眼外肌组织中抵抗素mRNA的表达情况;免疫组织化学法检测抵抗素蛋白在人眼眶脂肪组织及眼外肌组织中的表达。结果PCR产物电泳结果示抵抗素产物片段约500bp,脂肪组织中含量高于眼外肌组织。抵抗素蛋白表达位于胞浆,免疫组织化学显示人眼眶脂肪组织及眼外肌组织中有抵抗素蛋白存在。结论在人眼眶脂肪组织及眼外肌组织中可检测到抵抗素mRNA及蛋白的表达,抵抗素可能与眼眶炎性疾病,如Graves眼病、炎性假瘤等有一定的关系。  相似文献   
995.
996.
To investigate the prevalence of hypertension and associated risk factors in Chinese children with intellectual disability, a cross-sectional study was conducted in a sample of 558 children with intellectual disability aged 6–18 years in Hong Kong, and 452 (81.0%) with valid data were included in the data analysis. Blood pressure was measured according to a standard protocol. Hypertension was defined using the age-, gender-, and height-specific classification criteria recommended by the 2018 Chinese Guidelines for Children. Multivariate and hierarchical logistic regression was fitted to examine the associations of hypertension with potential risk factors. Overall, 31.4% of the participants were classified as having hypertension. Obese children were more likely to develop hypertension than non-obese children (adjusted OR = 2.77, 95% CI: 1.28, 5.99, p = 0.010). A paternal education of college or above and a paternal occupation of clerks, sales representatives, and workers were also associated with an increased risk of hypertension. The prevalence of hypertension is high among Chinese children with intellectual disability. Obesity was the strongest risk factor. Further longitudinal studies are warranted to confirm our findings. Nevertheless, preventions against obesity are promising to receive doubled benefits in reducing both obesity and hypertension, given its strong relationship with hypertension in this special population.  相似文献   
997.
Tobacco smoke exposure is known to lower serum 25-hydroxyvitamin D (25(OH)D) concentrations. This study evaluated the association between passive smoking and vitamin D deficiency (VDD) in young children using data from the Japan Environment and Children’s Study (JECS), the largest birth cohort study in Japan. Information on parental smoking status was extracted from a survey of JECS for children aged 1.5 years and data for serum 25(OH)D concentrations were obtained from blood tests in the Sub-Cohort Study of JECS performed at age 2 years. Logistic regression and linear models were fitted to evaluate the association between these variables. Data were analyzed for 4593 children. After adjusting for covariates, smoke exposure was significantly associated with increased incidence of VDD (OR 1.35; 95% CI, 1.14–1.59) according to the logistic model. The linear model indicated that passive smoking negatively predicted de-seasonalized serum 25(OH)D concentrations (β −0.5; 95% CI −0.95 to −0.08) in children aged 2 years. The results suggest that smoke exposure is a risk factor for VDD in children. Given that VD plays a crucial role in bone metabolism and the immune system, our findings are significant for clinical and public health.  相似文献   
998.
目的分析听神经病(auditory neuropathy,AN)患者在不同测试强度下的单音节识别率,总结AN患者在言语识别方面的特点。方法AN患者10例,共20耳。根据听力图形状将AN患者分为上升型听力组和非上升型听力组,两组分别包括12耳和8耳。分别在患耳0.5、1、2和4kHz纯音平均听阈(4FA)以及4FA上10dB、20dB、30dB共4个强度测试单音节识别率。绘制得分一强度(Performance--Intensity,P—I)函数曲线。结果AN患者的P—I曲线大致可以分为3段。在昕阈附近得分较低,在4FA+20dB处达到相对较高得分,平均最大言语识别率为42.8%±23.8%;在4FA+20dB以上得分没有随强度增加显著增长,而是总体得分呈轻微回跌。大多数AN患者P—I曲线呈非单调性,且变异范围较大,最大言语识别率得分的差异可达60%~70%。在各强度下,上升型听力组和非上升型听力组在全部4个强度下得分无统计学差异。结论AN患者的单音节P—I曲线呈现低得分、非单调、变异大的特点。  相似文献   
999.
Two Caucasian girls, both of normal weight and body mass indices, were diagnosed with type A insulin resistance (IR) in childhood. Case 1 presented with premature adrenarche aged 7 years, then by age 12 years had hirsutism, acne, acanthosis nigricans, and asymptomatic diabetes. Subsequent investigation revealed raised adiponectin (15.3 mg/L) and heterozygous p.Pro1205Leu mutation in the INSR gene encoding the insulin receptor. She experienced postprandial hypoglycaemia on metformin; acarbose was trialled and discontinued aged 16 years, as she became normoglycaemic. Hirsutism was treated with topical eflornithine, oral spironolactone and flutamide, and laser therapy. Unfortunately, diabetes reemerged in young adulthood with obesity. Case 2: during an emergency admission for acute abdominal pain aged 11 years, hyperglycaemia was noted which led to further investigation. An oral glucose tolerance test showed diabetes and ultrasound showed polycystic ovaries. Further investigations revealed raised adiponectin (18 mg/L) and compound heterozygous mutations in the INSR gene: p.Pro1263Ala and p.Ser748Leu (latter probable normal variant). She was treated with metformin and experienced postprandial hypoglycaemia. Symptoms of hyperandrogenism were controlled by flutamide. She maintained a healthy weight and reassessment at young adulthood showed resolution of diabetes. Type A IR may present in childhood with overlapping features of common endocrine entities such as premature adrenarche and polycystic ovarian syndrome. Patients with abnormal glucose tolerance yet normal weight merit screening with adiponectin; raised adiponectin levels prompt insulin receptor mutational analysis. Postprandial hypoglycaemia is characteristic. Management includes optimization of glycaemic control with oral hypoglycaemic agents and maintenance of healthy weight, and controlling the effects of hyperandrogenism.  相似文献   
1000.
目的 探讨胆道发育不良患儿的临床表现、病理特点、诊断、治疗及预后,提高对该病的认识.方法 回顾性分析天津市儿童医院外科2010年6月至2016年11月收治的5例胆道发育不良患儿的发病情况、治疗过程,并通过复习国内外文献对胆道发育不良的疾病特点进行总结.结果 5例胆道发育不良患儿均因生后不久出现皮肤、巩膜黄染,内科治疗病情无改善入外科治疗;肝功能检查见胆红素水平升高,以直接胆红素升高为主,伴肝酶不同程度增高;超声检查示胆囊干瘪未充盈或胆囊腔狭小,胆总管显示不清.5例患儿行手术探查,术中造影显示肝内、外胆道通畅,管腔纤细;病理检查见部分汇管区中小叶间胆管缺失,小叶间胆管/汇管区<0.5,诊断为胆道发育不良,予留置胆囊引流管,术后抗炎、补液、保肝及对症治疗.经2个月~6年门诊随访,5例患儿均存活至今,其中3例黄疸清除,1例皮肤仍黄染并伴有瘙痒,1例未退黄.结论 术前检查提示梗阻性黄疸患儿,术中造影提示胆道纤细,结合病理检查证实小叶间胆管/汇管区比例<0.5,可以明确胆道发育不良的诊断.  相似文献   
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