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71.
BACKGROUND: Plant fats and oils are major sources of mono- and polyunsaturated fatty acids as well as vitamin E, the major fat-soluble antioxidants in human nutrition. Dietary antioxidants are expected to reduce cancer risk by minimizing DNA damage. AIM OF THE STUDY: To compare the effects of gamma-tocopherol rich corn oil and the mixture of the alpha-tocopherol rich olive/sunflower oil on plasma concentration of tocopherols and on the frequency of sister chromatid exchange (SCE), an indicator of DNA damage. METHODS: This study had a double-blind, cross-over design and was conducted in 20 normal healthy non-smoking males aged 19-31 years. Design included a 2-week adjustment period and two 2-week test periods in which diets containing 30% energy as fat including either 80 g of corn oil (CO) (20 mg alpha-tocopherol, 100 mg gamma-tocopherol) or 80 g of olive/ sunflower oil (OSO) (24 mg alpha-tocopherol, 2.4 mg gamma-tocopherol), as the main fat-source, were given. Blood samples for analysis of SCE rate and content of tocopherols were collected at the beginning (T0), after adjustment (T1) and after the test period (T2) in intervals of 2 weeks. RESULTS: After two weeks of the corn oil diet, the plasma concentration of gamma-tocopherol increased but alpha-tocopherol decreased significantly compared to the olive/sunflower oil diet. The concentration of alpha-tocopherol increased (CO: 22.99 +/- 1.11 vs. OSO: 24.40 +/- 1.49 micromol/l) and that of gamma-tocopherol decreased (CO: 4.19 +/- 0.29 vs. OSO: 2.99 +/- 0.25 micromol/l) after the olive/sunflower oil diet. Intake of the corn oil diet was associated with reduced SCE rate and intensity, whereas there was no change in SCE after the olive/sunflower oil diet (CO: 7.66 +/- 0.25 vs. OSO: 8.06 +/- 0.47 mean SCE/cell) CONCLUSIONS: The combination of gamma-tocopherol with alpha-tocopherol in corn oil diet despite the lower alpha-tocopherol equivalents/diene acid equivalents ratio achieved better protection against DNA damage than alpha-tocopherol alone in the olive/sunflower oil diet.  相似文献   
72.
Imaging of septate gallbladder   总被引:1,自引:0,他引:1  
  相似文献   
73.
High-frequency ultrasound (US) is an efficient, rapid and inexpensive altenative to magnetic resonance imaging (MRI) for investigation of diseases in the soft tissues of the wrist and hand. US allows detection of foreign bodies and the reliable identification of a variety of traumatic lesions affecting tendons, annular pulleys, ligaments, vessels and nerves. Inflammatory diseases of tendons, including acute and chronic tenosynovitis and some degenerative conditions in the wrist and hand, can also be diagnosed. In entrapment neuropathies, US is able to identify nerve shape changes and possible extrinsic space-occupying lesions that may cause nerve compression within the tunnels. In patients with localized swelling of the hand or wrist, US is able to assess the presence of an expansile lesion and to characterize its nature in most cases. The objective of this article is to review the main findings and the primary indications of US in the investigation of disorders of the hand and wrist. Received: 10 September 1998 Accepted: 24 November 1998  相似文献   
74.
75.
The prevalence of antibodies against spotted fever group rickettsia (SFGR), murine typhus and Q fever were investigated in wild rats captured in Indonesia. Sera of 327 rats were collected from Jakarta and Boyolali on Java Island. The prevalences of antibodies against SFGR and murine typhus were 128 (39.1%) and 48 (14.7%), respectively. Antibodies against Q fever were not detected in these serum samples. Antibodies against SFGR were found in all species of rats (20.8–51.9%). The antibody positive rate against murine typhus in Rattus norvegicus (38.0%) was significantly higher than that in other rat species (0–4.8%, p < 0.01). The antibody positive rates against SFGR and murine typhus in rats captured in Jakarta were significantly higher than those in rats captured in Boyolali (p < 0.01). In this survey, all species of rats had antibodies against SFGR, indicating that the 4 species of tested rats (R. norvegicus, R. rattus, R. exulans, R. tiomanicus) were infected with SFGR and that SFGR may infest the whole of Java Island. Most of the rats that were antibody-positive against murine typhus were captured in Jakarta. Therefore, R. norvegicus and R. rattus are likely to be important hosts of murine typhus in Jakarta. The antibody-positive rates against SFGR and murine typhus in rats captured in the dry season were significantly higher than those in rats captured in the rainy season. This may coincide with the active periods of ticks and fleas in Indonesia.  相似文献   
76.
77.
The ability of some N,N-dialkylaminosubstituted chromones and isoxazoles to inhibit the protein kinase C (PKC) dependent signal transduction pathway was tested. As a cellular model, human neutrophils stimulated with either phorbol myristate acetate (PMA) or formylmethionine-leucine-phenylalanine (f-MLF) were used. The efficiency of the compounds was established by their capacity to reduce the O2- production by activated human neutrophils. Compounds carrying a 3-bis(2-methoxyethyl)amino group, a substituent found active in previously tested tricyclic compounds, do not show significant anti-PKC activity in this study. On the other hand, substitution with a 1-piperidinyl group leads all tested compounds to a high biological activity against stimulated neutrophils.  相似文献   
78.
This study was carried out to determine the risk of some social and biological maternal factors which may contribute to occurrence of anemia among mothers and preschool children. A community based comparative study was chosen for the conduction of this work. The target population were 400 women in the child bearing period, having at least one preschool child (440). Capillary blood samples were taken by finger prick method and hemoglobin level was estimated by Sahly method. According to the cut off level of hemoglobin, women were classified into anemic and non anemic. In addition to that, 440 preschool children belonging to these women were classified according to the cut off level of their hemoglobin into 165 anemic children and 275 non anemic ones. An interview questionnaire was used to collect the data. Analysis of results showed that age of mother (30 years and above), illiteracy, high parity, history of previous abortion, history of previous perinatal mortality, small inter-birth interval and non use of contraceptives are significant risk factors for mothers. However, mother occupation and state of pregnancy has no role in occurrence of anemia among mothers. In addition to that, high parity, history of previous abortion, history of perinatal mortality, short inter-birth interval, non use of contraceptives and pregnancy are maternal risk factors responsible for anemia among preschool children. While, mother age, education and occupation has no role for occurrence of anemia among preschool children.  相似文献   
79.
80.
Possible effects on the next generation after long-term exposure (subcutaneous administration) of male rats to very high doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were studied. Two dose regimes were applied: TCDD-25 (initial dose: 25 g/kg body wt; maintenance dose: 5 g/kg body wt, once weekly) and TCDD-75 (initial dose: 75 g/kg body wt; maintenance dose: 15 g/kg body wt). Male rats were treated for 10 weeks before mating and then throughout the entire 12 week mating period. They were mated to unexposed virgin females. One group of pregnant females was used for teratological evaluations, and another group was allowed to deliver. No significant differences were observed in the number of implantations or fetuses per litter, and resorption rate, and fetal weight between the controls and TCDD-treated groups. No gross-structural anomalies occurred in any of the fetuses sired by TCDD-treated males. In the TCDD-25 group an increased frequency of two types of variations was observed which also occur in controls: incompletely ossified fingers (TCDD-25=5.1%, controls=2.6%), and incompletely ossified ossa zygomatica (TCDD-25=1.8%, controls=0.5%). In the TCDD-25 group a slight but statistically significant increase was observed in the rate of stillbirths (TCDD-25=1.3%, controls=0.1%), apparently due to an unusually low frequency occurring in the controls (overall historical controls=0.6%). There was no difference in postnatal mortality (TCDD-25=1.3%, controls=1.3%). Taken together, despite the very high doses of TCDD used, the data do not provide evidence for biologically significant paternally-mediated developmental toxicity in the fetuses and newborn.  相似文献   
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