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51.
Human milk has always been the reference parameter for the preparation of commercial formulae. The advent of more advanced technologies has enabled increasingly precise information on the composition of human milk to be obtained. Our knowledge in the field of carbohydrates also has improved considerably in the last few years following the pioneering studies of Montreuil (1, 2). From a quantitative point of view it has been demonstrated that in the different phases of lactation, in addition to lactose, human milk contains a consistent amount of oligosaccharides (about 20 g/1 in colostrum and 10–13 g/l in mature milk) (3, 4), whereas monosaccharides make up only about 1% of the total carbohydrates (4). More than 100 different types of oligosaccharides have been identified so far in human milk (5–7), mostly tri-octasaccharides (8). From a biochemical point of view, oligosaccharides are constituted by glucose, galactose, N -acetyl-glucosamine, fucose and sialic acid, and present a linear or branching structure (5). Little is known yet about their physiological role or metabolic fate (9); nevertheless, it has been demonstrated that, in addition to their nutritional function, they participate also in the regulation of the intestinal ecosystem, encouraging the growth of bifid flora (10) and contributing to the defense mechanisms against pathogens in various organs (11–13).  相似文献   
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We evaluated the effects of pretreatment with ethanolic neem leaf extract on 7,12-dimethylbenz[a]anthracene (DMBA)-induced genotoxicity and oxidative stress in male Swiss albino mice. The frequency of bone marrow micronuclei, the extent of hepatic lipid peroxidation and the status of antioxidants-reduced glutathione (GSH), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were used as intermediate biomarkers of chemoprotection. In DMBA-treated mice, the increases in micronuclei and lipid peroxides were accompanied by compromised antioxidant defenses. Pretreatment with ethanolic neem leaf extract (200 mg/kg body weight) significantly reduced DMBA-induced micronuclei and lipid peroxides and enhanced GSH-dependent antioxidant activities. The results of the present study suggest that ethanolic neem leaf extract exerts protective effects against DMBA-induced genotoxicity and oxidative stress by enhancing the antioxidant status.  相似文献   
53.
The efficacy of a single round of screening of visual inspection with acetic acid (VIA) on cervical cancer incidence and mortality is investigated in a cluster randomized controlled trial in south India. Women aged 30-59 years in 113 clusters in Dindigul District were randomized to VIA screening by nurses (57 clusters, 48,225 eligible women) and to a control group (56 clusters, 30,167 women). 30,577 (63.4%) eligible women participated in screening. Younger, educated, married, multiparous, low-income women and those who have had tubal sterilization had a higher compliance with screening. Of the 2069 women diagnosed with CIN and invasive cancer, 1498 (72.4%) received treatment. Young women, those who practiced contraception and women with high-grade precursor lesions and invasive cancers were more likely to comply with treatment. In summary, our study indicates that women accept screening with VIA by nurses and a moderate level of compliance with screening and treatment can be reached through appropriate service delivery systems including health education activities, personal invitations, clinics in proximity to the target women, and testing and treatment in the same session. Our results imply that integration of screening activities with primary health services seems to have the potential to replicate most of these service delivery conditions in routine programs.  相似文献   
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This study investigated the retreatment effectiveness of .04 Taper nickel-titanium rotary ProFiles. Thirty extracted single-rooted anterior teeth were instrumented and obturated with gutta-percha/Roth's Sealer using lateral condensation. They were distributed into three groups of 10 each. Retreatment for group A was done using Profile alone, group B using Profile and chloroform, and group C using hand files with chloroform. The teeth were then split longitudinally into halves. The remaining gutta-percha/sealer on the root canal wall in the cervical, middle, apical thirds, and the whole canals were visually scored with the aid of light microscopes. The results showed that the mean scores in groups A and B were generally lower (better) than group C. Mean scores of the apical thirds tended to be higher (worse) than the middle and the cervical thirds, except in group A. ProFile with or without chloroform seemed to be a viable alternative retreatment method.  相似文献   
57.
Oral squamous cell carcinoma, the fifth most common cancer worldwide, is a major cause of morbidity and mortality in India. The effect of lifestyle factors, including tobacco chewing, smoking and alcohol drinking, diet and dental care, on the risk of oral cancer was investigated in a case-control study conducted in Rajah Muthiah Dental College and Hospital, Annamalainagar, Annamalai University, Chidambaram, Tamil Nadu, India during the period 1991-2003. The study included 388 oral squamous cell carcinoma cases and an equal number (388) of age and sex-matched controls. All participants were interviewed using a structured questionnaire that contained data on demographic factors, family history of cancer, tobacco habits, use of alcohol, frequency, duration, cessation of these habits, dietary practices and oral hygiene. The data were analysed using multiple logistic regression model. Among people with chewing habits, those who chewed betel quid with tobacco [odds ratio (OR) 3.19, 95% confidence interval (CI): 0.48-2.13] and tobacco alone (OR 2.89) showed a greater risk than controls. Bidi smoking (OR 4.63) and alcohol drinking (OR 1.65) emerged as significant risk factors for oral cancer. These three habits showed increasing risk with increasing frequency and increase in duration of habits. Addition of alcohol to other habits also enhanced the risk for oral cancer. The combination of chewing and smoking together with alcohol drinking showed very high relative risk (OR 11.34). A positive association was observed between non-vegetarian diet, poor oral hygiene and poor dentition with the risk of oral squamous cell carcinoma. The fact that these risk factors are modifiable emphasizes the need for increasing awareness among the general public and policy makers as a first step in the prevention and control of oral squamous cell carcinoma.  相似文献   
58.
Phosphatidylinositol 3-kinase (PI3 kinase) inhibition disrupts the ability of insulin to stimulate GLUT1 and GLUT4 translocation into the cell membrane and thus glucose transport. The effect on GLUT4 but not on GLUT1 is mediated by activation of protein kinase B (PKB). The serum- and glucocorticoid-inducible kinase SGK1, a further kinase downstream of PI3 kinase, regulates several transporters by enhancing their plasma membrane abundance. GLUT1 contains a consensus site ((95)Ser) for phosphorylation by SGK1. Thus, the present study investigated whether GLUT1 is regulated by the kinase. Tracer-flux studies in Xenopus oocytes and HEK-293 cells demonstrated that GLUT1 transport is enhanced by constitutively active (S422D)SGK1. The effect requires the kinase catalytical activity since the inactive mutant (K127N)SGK1 failed to modulate GLUT1. GLUT1 stimulation by (S422D)SGK1 is not due to de novo protein synthesis but rather to an increase of the transporter's abundance in the plasma membrane. Kinetic analysis revealed that SGK1 enhances maximal transport rate without altering GLUT1 substrate affinity. These observations suggest that SGK1 regulates GLUT1 and may contribute to or account for the PI3 kinase-dependent but PKB-independent stimulation of GLUT1 by insulin.  相似文献   
59.
目的:探讨99mTcO4-甲状腺显像定量分析在甲状腺疾病诊断中的临床价值。方法:采用Marconi Fx810 SPECT仪对38例正常对照者和189例Graves病、亚急性甲状腺炎、单纯性甲状腺肿及甲状腺功能减退者进行99mTcO4-甲状腺动静脉态双时相显像,测定颈动脉与甲状腺显影时间差(Td)及20分钟时甲状腺与颈部软组织像素的平均放射性比值(UI)。结果:①Graves病组表现为Td缩短,UI值明显增高,且UI值恢复速度滞后于体外甲功指标的恢复(P<0.01)。②亚甲炎组甲状腺摄锝功能降低(P<0.01),静态显像表现为放射性普遍稀疏或局限性稀巯。③单甲肿组、甲减组Td、UI值与正常组无明显差异(P>0.05)。④对照组、Graves病、亚甲炎及单甲肿组24小时吸131I率与UI值有良好的相关性。结论99mTcO4-甲状腺显像定量分析法操作简便,误差小,适用范围广,在常见甲状腺疾病的诊断中具有重要价值。  相似文献   
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