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91.
Mercury ingested from dietary sources has potent neurotoxic and teratogenic effects. Initial studies have shown that mercury may also affect fetal lung development. Since these pulmonary effects may play a role in subsequent neonatal morbidity and mortality due to compromising of the development of the lung, mercury effects in fetal and neonatal lung were investigated. Methylmercuric chloride (MMC), 1,000 ppm (15 mg/kg of body weight), was administered via an intragastric tube to timed-pregnant Swiss/Webster mice on day 9 of gestation. Lungs from fetuses on gestational day 18 and from neonates on days 1, 5, or 10 after birth were studied. Significant changes in MMC-exposed lungs compared to controls occurred at postnatal day 1. At this time, lung weight per gram body weight increased, phospholipid content per gram of lung or per microgram of DNA decreased, while DNA per gram of lung increased. Methylmercury appears to have delayed lung maturation. Cuboidal epithelial cells in alveolar tubules contained conspicuous glycogen deposits, and differentiation of alveolar type II cells was adversely affected. These results suggest that prenatal exposure to methylmercury may be detrimental to lung development, specifically to the initiation of surfactant synthesis, by delaying the normal pattern of maturation of the alveolar type II cells within the lungs. Pediatr Pulmonol. 1994; 17:11–21 . © 1994 Wiley-Liss. Inc. 相似文献
92.
C Lévy-Marchal L Papoz C de Beaufort J Doutreix V Froment J Voirin P Czernichow 《Diabetic medicine》1992,9(3):279-284
The French incidence study has registered all new cases of Type 1 diabetic children under 20 years of age, from a population of 2.32 million, in an exhaustive and prospective manner. Three hundred and forty cases were identified between 1 January 1988 and 31 December 1989, yielding a mean annual incidence rate 7.3 per 10(5). The lowest rate was observed in the youngest age group (0-4 yr: 4.1 per 10(5)) and the highest around pubertal development (10-14 yr: 11.5 per 10(5)). Details of the previous personal and family history, and the clinical and biological pictures of the disease at diagnosis were recorded. Almost 8 per cent of the children had a first-degree relative with Type 1 diabetes. Polyuria, weight loss, fatigue and abdominal pain were the most frequently reported symptoms, which were of median duration 4.4 months. Mean weight loss before diagnosis was 9.4 +/- 6.8 (+/- SD)% of body weight and was not significantly related to age. Ketonuria was detected in 83.8 per cent and acidosis (total CO2 less than or equal to 18 mmol l-1, if measured) in 48 per cent of the cases. Ketonuria and acidosis were significantly more frequent in the younger age group than in the rest of the group (p less than 0.001). 相似文献
93.
目的研究 1型蛋白磷酸酶骨骼肌特异的糖原靶向调节亚单位基因 (PPP1R3) Asp90 5 Tyr多态性与安徽汉族人 2型糖尿病 (T2 DM)相关性。方法选取安徽省合肥地区汉族 T2 DM患者 2 6 2例 ,健康成人 10 4例 ,运用聚合酶链反应限制性酶切片段长度多态性技术 (PCR- RFL P)进行基因型测定。以体质指数 (BMI) 2 5为分割点 ,将病例组和对照组进行分层分析。结果 1PPP1R3基因 Asp90 5 Tyr多态性与安徽汉族人 2型糖尿病没有明显的相关性。 2以 BMI<2 5基因型Tyr/ Tyr组为参照组 ,BMI≥ 2 5携有 Asp90 5等位基因个体的糖尿病发病风险明显增加 (OR=3.6 9;95 % CI:1.38~ 8.89;P=0 .0 0 6 )。结论 PPP1R3基因 Asp 90 5 Tyr多态性可能不是安徽省汉族人 2型糖尿病主要的致病因素。肥胖与 Asp90 5等位基因间的交互作用可增加糖尿病的发病风险。 相似文献
94.
The glucose clamp technique is currently regarded as the standard test for measuring insulin sensitivity against which other methods are compared but is unsuitable for routine screening of patients outside a hospital base. There is thus a need for a simpler test to measure insulin sensitivity. We have therefore compared the glucose disappearance rate KITT in the first 15 min of the insulin tolerance test (ITT) with the M and M/I values derived from the standard euglycaemic clamp in nine normal subjects and eight subjects with Type 2 (non-insulin dependent) diabetes mellitus and coexisting obesity. All subjects underwent the ITT and euglycaemic clamp in random order. Nine subjects later had a repeat ITT to determine the reproducibility of the test. In the ITT, 0.1 U kg-1 body weight, human Actrapid insulin was given as an IV bolus and simultaneous arterialized and venous blood samples were obtained every minute for 15 min. The first order rate constant for the disappearance of glucose KITT over the period 3-15 min was taken as a measure of insulin sensitivity. The euglycaemic clamp was performed with an insulin infusion of 50 mU kg-1 h-1 for 120 min and a variable rate glucose infusion to maintain blood glucose concentration at 0.5 mmol l-1 below fasting level to minimize the effect of endogenous insulin secretion. The ratio of the mean rate of glucose infused (M, mumol kg-1 min-1) to the plasma insulin over the last 30 min of the clamp was taken as a measure of tissue sensitivity to insulin (M/I) assuming endogenous glucose output was suppressed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
目的 分离鉴定青叶胆 Swertia mileensis全草的酮类成分。方法 95 %乙醇浸提 ,经硅胶柱色谱分离纯化 ,UV,IR,MS,1 H和 1 3CNMR波谱方法确定化学结构。结果 分得 12个酮成分 ,分别为 1-羟基 - 2 ,3,4 ,5 -四甲氧基酮 (1- hydroxy- 2 ,3,4 ,5 - tetramethoxyxanthone, ) ;1-羟基 - 2 ,3,7-三甲氧基酮 (1- hydroxy- 2 ,3,7-trim ethoxyxanthone, ) ;1-羟基 - 2 ,3,5 ,7-四甲氧基酮 (1- hydroxy- 2 ,3,5 ,7- tetram ethoxyxanthone, ) ;1,5 -二羟基 - 2 ,3-二甲氧基酮 (1,5 - dihydroxy- 2 ,3- dimethoxyxanthone, ) ;1,5 -二羟基 - 2 ,3,7-三甲氧基酮 (1,5 - dihy-droxy- 2 ,3,7- trimethoxyxanthone, ) ;1-羟基 - 2 ,3,5 -三甲氧基酮 (1- hydroxy- 2 ,3,5 - trimethoxyxanthone, ) ;1,5 -二羟基 - 2 ,3,4 ,7-四甲氧基酮 (1,5 - dihydroxy- 2 ,3,4 ,7- tetramethoxyxanthone, ) ;1,8-二羟基 - 2 ,3,6 -三甲氧基酮 (1,8- dihydroxy- 2 ,3,6 - trimethoxyxanthone, ) ;1-羟基 - 2 ,3,4 ,7-四甲氧基酮 (1- hydroxy- 2 ,3,4 ,7- te-tramethoxyxanthone, ) ;1,2 ,3,5 -四甲氧基酮 (1,2 ,3,5 - tetromethoxyxanthone, ) ;1-羟基 - 2 ,3,4 ,6 -四甲氧基酮 (1- hydroxyl- 2 ,3,4 ,6 相似文献
96.
细胞因子与2型糖尿病及胰岛素抵抗的相关性研究 总被引:4,自引:0,他引:4
目的 研究2型糖尿病及胰岛素抵抗患者白细胞介素6(IL-6)、白细胞介素8(IL-8)及肿瘤坏死因子α(TNF—α)的变化,分析细胞因子与糖尿病及胰岛素抵抗的相关性。方法 采用酶联免疫吸附法测定90例2型糖尿病患者及30例正常人血清各细胞因子浓度,并同时测定空腹血糖(FPG)、糖化血红蛋白、空腹胰岛素(FINS)及空腹C肽(FCP)水平,分析其与细胞因子的相关性。结果 与正常对照组比较2型糖尿病组血清细胞因子的含量均明显增高(P〈0.01、P〈0.05);胰岛素抵抗组的IL-6、TNF—α升高与非胰岛素抵抗组比较差异有统计学意义(P〈0.05),胰岛素抵抗与细胞因子的增高密切相关。结论 2型糖尿病患者存在着细胞因子的过度激活,并与胰岛素抵抗密切相关,细胞因子在2型糖尿病及胰岛素抵抗的发生发展中起着重要的作用。 相似文献
97.
Levels of cardiovascular risk factors were determined in 75 patients with Type 2 diabetes mellitus. The patients were divided into three groups according to their urinary protein excretion (UPE): (a) normal proteinuria (less than or equal to 70 mg d-1); (b) microproteinuria (70-500 mg d-1); and (c) macroproteinuria (greater than 500 mg d-1). A significant stepwise increase in mean systolic blood pressure, LDL-cholesterol and fibrinogen levels was observed from the first to the third investigated group of patients. Mean apoprotein B levels were significantly increased in the group with macroproteinuria compared to the other two groups. Significant linear correlations were found between UPE and LDL-cholesterol, total cholesterol, apoprotein B, creatinine, systolic blood pressure and diabetes duration. In summary, it is concluded that the levels of some cardiovascular risk factors increase with the stage of proteinuria in Type 2 diabetes mellitus. 相似文献
98.
L M Delahanty R W Grant E Wittenberg J L Bosch D J Wexler E Cagliero J B Meigs 《Diabetic medicine》2007,24(1):48-54
AIMS: To characterize the determinants of diabetes-related emotional distress by treatment modality (diet only, oral medication only, or insulin). METHODS: A total of 815 primary care patients with Type 2 diabetes completed the Problem Areas in Diabetes (PAID) Scale and other questions. We linked survey data to a diabetes clinical research database and used linear regression models to assess the associations of treatment with PAID score. RESULTS: PAID scores were significantly higher among insulin-treated (24.6) compared with oral-treated (17.8, P < 0.001) or diet-treated patients (14.7, P < 0.001), but not different between oral- vs. diet-treated patients (P = 0.2). Group scores remained similar, but the statistical significance of their differences was reduced and ultimately eliminated after sequential adjustment for diabetes severity, HbA(1c), body mass index, regimen adherence, and self-blood-glucose monitoring. Insulin-treated patients reported significantly higher distress than oral- or diet-treated patients on 16 of 20 PAID items. 'Worrying about the future' and 'guilt/anxiety when ... off track with diabetes' were the top two serious problems (PAID >or= 5) in all treatment groups. Not accepting diabetes diagnosis was a top concern for oral- and diet-treated patients, and unclear management goals distressed diet-treated patients. CONCLUSIONS: Primary care patients treated with insulin reported higher diabetes-related emotional distress compared with oral- or diet-treated patients. Greater distress was largely explained by greater disease severity and self-care burdens. To improve diabetes-specific quality of life, clinicians should address patients' sense of worry and guilt, uncertain acceptance of diabetes diagnosis, and unclear treatment goals. 相似文献
99.
100.
2型糖尿病肾病患者血清中TNF-α、NO与ET的水平变化及其临床意义 总被引:1,自引:0,他引:1
目的:探讨2型糖尿病肾病患者血清肿瘤坏死因子仅(TNF-α)、一氧化氮(NO)和内皮素(ET)的水平变化及其临床意义。方法:用ELISA法检测91例2型糖尿病患者血清TNF-α水平,NO与ET的水平分别用硝酸还原酶法和放射免疫法测定。结果:2型糖尿病肾病各组患者TNF-α和ET水平较对照组明显升高,其中ODN组最高(P〈0.01)。而2型糖尿病肾病各组患者血清NO水平较对照组明显减少(P〈0.01)。显性糖尿病肾病患者血清TNF-α和ET呈正相关;血清TNF-α和NO、ET和NO均成负相关。结论:TNF-α、NO与ET可能参与2型糖尿病肾病的发病及病程变化过程,检测患者TNF-α、NO与ET水平可作为判断预后、指导治疗的指标。 相似文献