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91.
Understanding diet and energy balance as risk factors for breast, colon,
and other cancers requires information on the contribution of each factor
and of interactions among factors to cancer risk. Rodent models for breast
cancer provide extensive data on effects of dietary fat and calories,
energy balance, body weight gain, and physical activity on tumor
development. Analyses of the combined data from many studies have shown
clearly that quality and quantity of dietary fat and energy balance
contribute independently to increased mammary gland tumorigenesis. These
findings were seen in female rats fed diets high in fat (35-40% of
calories) compared to rats fed control diets, with approximately 10% of
calories as fat (Fay and Freedman, 1997, Breast Cancer Res. Treat. 46,
215-223). The methods used permit comparison of experimental and
epidemiological data, and they may be useful in extrapolating between
species and developing public health recommendations. In addition to the
contributions of lifetime-diet composition, intake, energy balance, and
physical activity to cancer risk, there are questions about the timing and
duration of alterations in these factors and about the "dose-response"
characteristics of cancer risk to the factors. Endocrine mechanisms may be
significant in mammary gland tumor risk, but experimental and
epidemiological data indicate that cancers at other sites, such as colon
and liver, also are influenced by the factors listed. Other diet and
lifestyle factors that influence energy, or specifically fat, metabolism
may also affect risk for cancers that are promoted by increased intake of
fat and calories. Studies of separate and interactive effects of dietary
fat, black tea, weight gain, and mammary gland tumorigenesis (Rogers, et
al, 1998, Carcinogenesis 19, 1269-1273) have been analyzed. Using
adjustment of carcinogenesis endpoints for body weight, tumor burden, and
latency, they were found to be related to weight gain within treatment
groups in 2 of 3 experiments.
相似文献
92.
V Launonen K Laake P Huusko D Niederacher M W Beckmann R B Barkardottir E K Geirsdottir J Gudmundsson P Rio Y J Bignon S Seitz S Scherneck I Bièche M H Champème D Birnbaum G White J Varley M Sztán E Olah A Osorio J Benitez N Spurr N Velikonja B Peterlin R Winqvist 《British journal of cancer》1999,80(5-6):879-882
High frequencies of loss of heterozygosity (LOH) in chromosome 11q22-qter have been observed in various malignancies, including breast cancer. Previous studies on breast carcinomas by Winqvist et al (Cancer Res 55: 2660-2664) have indicated that a survival factor gene is located in band 11q23, and that the highly informative microsatellite polymorphism at the APOC3 locus would be a suitable tool to perform more extensive LOH studies. In this European multicentre study, we have examined the occurrence of APOC3 LOH and evaluated the effect of LOH of this chromosomal subregion on the clinical behaviour of the disease in a cohort of 766 breast cancer patients in more detail. LOH for APOC3 was found in 42% of the studied tumours, but it was not found to be significantly associated with any of the studied clinical variables, including cancer-specific survival time or survival time after recurrent/metastatic disease. According to the present findings, the putative survival factor gene on 11q23 is not located close enough to the APOC3 gene, but apparently at a more proximal location. 相似文献
93.
Temporal bone histopathology is reported on a case of acute suppurative otitis media, acute suppurative labyrinthitis, and meningitis with death of the patient 20 days after stapes surgery. Purulent exudate invaded the vestibule by the oval window through a displaced footplate. The main pathway of infection to the menings was extension along the branches of the vesticular nerve to the internal auditory meatus and to the subarachnoid space. 相似文献
94.
A. Reyes R. Pacifico B. Benitez E. Villanueva‐Uy H. Lam E. M. Ostrea Jr 《Child: care, health and development》2010,36(3):354-360
Background There is a need to assess neurobehavioral performance of children in developing countries using standardized developmental tools. Methods The Griffiths Mental Development Scales was evaluated in the Philippines by comparing the performance of 742 Filipino children longitudinally at 6, 12 and 24 months old to those of their British counterparts. Results The mean general and subquotient scores of Filipino children were all within average for age. Comparison with British children showed that except for performance subscales, Filipino children had significantly higher developmental subquotients at 6 months old. As the Filipino infants grew older, their developmental subquotients in all subscales were significantly lower, except for personal and social skills at 24 months old. The genetic predisposition as evidenced by modest maternal scores on the Wechsler Intelligence Scales and lack of familiarity with test materials are factors that may influence the developmental patterns of Filipino children. Conclusion Although the performance of the Filipino children in the Griffiths test were within average with age, their performance on developmental subquotients at later ages of 12 and 24 months were significantly lower than British children and may have been influenced by differences in ethnicity, cultural traditions and limited environmental resources. 相似文献
95.
J C Ramirez A J Puerta A Rebollo R Benitez A Pe?a J C de la Macorra 《European urology》1987,13(5):346-350
A case of Rokitansky's syndrome in association with complete duplication of the right upper urinary tract is presented. From a chronological point of view, the morphogenetic processes of the urinary and genital tract are analyzed. It is supposed that the congenital abnormality is produced between the 30th and 37th day of gestation, because reno-ureteral duplication appears at 30-32 days and involution of the Müllerian structures appears at 37 days. 相似文献
96.
The action of naloxone (0.5 and 2 mg/kg IP) on the behavioural effects of a low (2 g/kg PO) and a high dose (4 g/kg PO) of ethanol was studied in rats. Ethanol at the low dose increased spontaneous motility, enhancing open-field external ambulations and reducing shuttle-box latency. All these effects were antagonized by naloxone. Ethanol at the high dose produced hypomotility, decreasing open-field external ambulations and impairing shuttle-box performance. In this case, naloxone also reduced the ethanol effect, but its action was less consistent. Therefore, although mechanisms other than a specific opioid receptor blockade by naloxone must be considered, an involvement of opioid peptides in the effects of ethanol cannot be discounted. 相似文献
97.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
98.
99.
Daniel TP Fong Mak-Ham Lam Miko LM Lao Chad WN Chan Patrick SH Yung Kwai-Yau Fung Pauline PY Lui Kai-Ming Chan 《Journal of orthopaedic surgery and research》2008,3(1):7
Background
Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running. 相似文献100.