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81.
Loss of tumor-promoting activity of unleaded gasoline in N- nitrosodiethylamine-initiated ovariectomized B6C3F1 mouse liver 总被引:1,自引:0,他引:1
Unleaded gasoline (UG) vapor (2056 ppm) increased the incidence of liver
tumors in a chronic bioassay and exhibited tumor-promoting activity in
N-nitrosodiethylamine (DEN)-initiated female mouse liver. Estrogen
inhibited mouse liver tumor development and the hepatocarcinogenic and
tumor-promoting dose of UG produced uterine changes suggestive of estrogen
antagonism. To directly test the hypothesis that UG-induced tumor-promoting
ability is secondary to its interaction with the mouse liver tumor
inhibitor, estrogen, we compared the tumor-promoting ability of UG in
ovariectomized (Ovex) mice with the hepatic tumor-promoting ability of UG
in intact mice. Ovaries were surgically removed at 4 weeks of age. Exposure
to wholly vaporized UG (2018 ppm) under bioassay and tumor-promoting
conditions began at 8 weeks of age. After 4 months of exposure, UG
increased relative liver weight and hepatic microsomal cytochrome P450
pentoxyresourfin-O- dealkylase and ethoxyresorufin-O-deethylase activity to
a similar extent in intact and Ovex mice. Non-focal hepatocyte
proliferation, as measured by the incorporation of bromo-deoxyuridine, was
not changed by UG exposure and was similar in all treatment groups. After 4
months of exposure to DEN-initiated mice, UG significantly increased the
volume fraction of liver occupied by foci (three-fold) as compared to
control intact mice. As expected, volume of foci was elevated in
DEN/Ovex/control mice as compared to DEN/intact/control mice. In DEN/Ovex
mice UG did not significantly increase the focal volume fraction. Thus, the
tumor promoting activity of UG, as demonstrated by increased volume
fraction of liver occupied by hepatic foci in intact mice, is greatly
attenuated in Ovex mice. The volume fraction data in Ovex mice support the
hypothesis that the tumor promoting activity of UG is dependent upon the
interaction of UG with ovarian hormones. These data also indicate that
hepatic microsomal cytochrome P450 PROD and EROD induction, hepatomegaly
and non-focal hepatic LI are not specific markers of hepatic tumor
promoting activity of UG.
相似文献
82.
Zhang GJ; Tsuda H; Adachi I; Fukutomi T; Yamamoto H; Hirohashi S 《Japanese journal of clinical oncology》1997,27(6):371-377
Patients with primary breast carcinoma with one to three axillary lymph
node metastases but without distant metastases (n1-3) in Japan have been
shown to have a 10-year disease-free survival rate of > 60%. It would be
reasonable to divide n1-3 Japanese breast cancer patients into groups with
high- or low-risk for recurrence and to consider post-operative adjuvant
therapy. In the present study, we analyzed 228 consecutive Japanese
patients with n1-3 breast cancer who underwent radical mastectomy and were
followed up for a median time of 11.0 years. The expression of bcl-2, p53
and c-erbB-2 proteins in the primary tumors was examined
immunohistochemically and their prognostic roles were also analyzed along
with conventional clinicopathologic indicators. bcl-2 expression was
correlated with positive estrogen receptor status and inversely correlated
with p53, c-erbB-2 and histologic grade. Univariate analysis showed that
bcl-2, p53 and c-erbB-2 expression were prognostic indicators of the
patient's group as well as node status, histologic grade, tumor size, age
at diagnosis, menopausal status and estrogen receptor status. Cox's
regression analysis demonstrated that the number of nodes involved,
menopausal status, p53 and bcl-2 were independent predictors for overall
survival and that histologic grade and the number of nodes involved were
independent predictors for disease-free survival. These results suggest
that bcl-2 expression in combination with p53 and c-erbB-2 expression, the
number of lymph node metastases, histologic grade and menopausal status are
useful in selecting subgroups of n1-3 breast cancer patients with good or
poor prognoses.
相似文献
83.
Angelie Lee MBBS Michael Permezel MD MRCP MRCOG FRACOG Peta Dennington FRCPA Trevor Duke MBBS Lex Doyle MD FRACP Hugh Robinson MD FRCOG FRACOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1993,33(4):420-423
Summary: A 32-year-old woman in her third pregnancy underwent fetal blood sampling because of a previous child with neonatal thromboeytopenia. At 33 weeks' gestation, fetal thromboeytopenia was diagnosed. Treatment was instituted antenatally with serial fetal platelet transfusions and corticosteroid therapy. Delivery was by Caesarean section at 37 weeks' gestation. Neonatal treatment included further platelet transfusion and immunoglobulin infusion. Recovery of the neonate was complete on discharge from hospital 10 days after birth. The aetiology, diagnosis, clinical presentations and therapeutic options in cases of alloimmune thromboeytopenia are discussed. 相似文献
84.
Risk factors for deaths in under-age-five children attending a diarrhoea treatment centre 总被引:2,自引:0,他引:2
Few case-control studies have examined possible risk factors for diarrhoeal deaths in under-age-five children in the developing countries. We analysed data from the surveillance system of our diarrhoea treatment centre/hospital for the period 1990-94 on 928 children less than 5 years of age. In univariate analysis, 11 factors were significantly associated with death: lack of breastfeeding, severe malnutrition, complicated diarrhoea, pneumonia, xerophthalmia, duration of diarrhoea 7-14 days, moderate or severe dehydration, recent history of measles, Shigella flexneri infection, maternal illiteracy, and very low household income. Rotavirus diarrhoea was negatively associated with fatal outcome. In the assessment of severe malnutrition, weight-for-height measurement discriminated mortality risk better than weight-for-age or height-for-age indices. Only two factors retained their significance, severe malnutrition and non-breastfeeding in the multivariate analysis with adjusted odds ratio (95% confidence interval) of 84.2 (9.1, 775.9) and 4.2 (1.3, 13.2) respectively. 相似文献
85.
OBJECTIVE: To assess the reactions of parents and their children to the request for a blood sample and an attempt to take blood. METHODS: 1859 children aged 1.5-4.5 years took part in a national survey of diet and nutrition. A retrospective inquiry of the parents' and children's reported reactions was carried out six to 18 months later by postal questionnaire sent only to the 1157 who had given consent for an attempt to take blood. RESULTS: 866 questionnaires were returned; 790 were from parents of children in whom an attempt to take blood had been successful. Thirteen per cent said that their child had given blood previously. About 30% discussed the request with the family doctor or nurse. Some 90% said that they were given enough information and that the phlebotomist was sympathetic. Attempting to take blood caused upset in over 50%, which, in most, lasted for less than five minutes. A substantial minority were upset for up to 30 minutes and a few much longer. Bruising or bleeding occurred in 20-27%. Degree and duration of upset were both adversely associated with a failed attempt to obtain blood. CONCLUSION: The majority of preschool children experienced no more than a little upset of short duration after an attempt to take blood, but a substantial minority exhibited a greater degree of upset. These responses should be taken into account when assessing the benefits and risks of the procedure. The best equipment and expertise should be employed for taking blood as successful attempts are less upsetting. 相似文献
86.
GJ Fuchs P Tienboon S Linpisarn S Nimsakul P Leelapat S Tovanabutra V Tubtong M DeWier RM Suskind 《Archives of disease in childhood》1996,74(3):224-227
Abnormal growth is a common feature of thalassaemia major in children. In an attempt to determine whether it has a nutritional cause, 12 children aged 1 to 3 years with thalassaemia major were studied under metabolic ward conditions. Nutritional status was assessed by anthropometry and biochemistry before and after an intensive nutrition regimen. Five children had wasting or stunting on admission. As a result of the nutrition intervention, mean weight for height improved significantly. The mean height increase of 0.4 cm after one month was not significant. Plasma zinc, depressed in half the children on admission, improved, as did alpha tocopherol, while copper decreased. Plasma insulin-like growth factor-I also increased commensurate with improved growth. Fat absorption was normal in all children. Undernutrition is an important cause of associated growth disturbances in children with thalassaemia major. Malnutrition was primarily caused by inadequate nutrient intake, as indicated by the capacity to gain weight appropriately when provided with nutrition support, and by the absence of intestinal malabsorption. While long term studies are required to determine if nutritional support will prevent stunting, these results underscore its central role in preventing nutritional deficiencies and in promoting normal growth in thalassaemic children. 相似文献
87.
A focus group study of women exposed to diethylstilbestrol (DES) in utero (DES daughters) was conducted to gain understanding about exposure to this drug from a patient perspective. Focus group participants reported that learning about their DES exposure was devastating; they experienced strains in their family relationships, emotional shock, a feeling that their health concerns were not appreciated by others and, to some degree, a sense of social isolation. Although many were aware of the need for special gynecological exams and high-risk prenatal care, they were frustrated by what they felt was a lack of reliable and clear information about the effects of DES exposure. Most expressed questions and anxiety about their health. Many found their communication with physicians about their DES exposure unsatisfying. They felt that physicians lacked information about the long-term health effects of DES exposure and as a result did not give them accurate information. Furthermore, they felt that physicians were dismissive of their concerns and often gave what they felt to be false reassurances. Consequently, the women developed an enduring distrust of the medical profession. The results of the study suggest implications for the delivery of health care to DES daughters. 相似文献
88.
Taraneh Gharib Nazem Lucky Sekhon Joseph A Lee Jessica Overbey Stephanie Pan Marlena Duke Christine Briton-Jones Michael Whitehouse Alan B Copperman Daniel E Stein 《Reproductive biomedicine online》2019,38(2):169-176
Research question
Does the composite morphology score or a particular developmental component (expansion stage, inner cell mass [ICM] or trophectoderm [TE]) of euploid blastocysts undergoing single frozen embryo transfer (FET) impact ongoing pregnancy/live birth (OP/LB) rates?Design
Retrospective cohort study including a total of 2236 embryos from 1629 patients who underwent single euploid FET between 2012 and 2017.Results
Embryos with an ICM grade of A compared with C had a higher OP/LB rate (55.6% versus 32.3%, P < 0.001). Blastocysts with a TE grade of A or B compared with C had a higher likelihood of OP/LB (A versus C: odds ratio [OR] 1.6, 99% confidence interval [CI] 1.1–2.3, B versus C: OR 1.5, 99% CI 1.1–2.1), and blastocysts with a developmental stage of 4 or 5 compared with 6 had higher odds of OP/LB (4 versus 6: OR 1.6, 99% CI 1.2–2.2, 5 versus 6: OR 1.6, 99% CI 1.2–2.3).Conclusions
Among euploid embryos, ICM morphology is the best predictor of sustained implantation; however, a composite score may provide additional guidance. While there is a known benefit in genomic screening prior to embryo selection, morphology provides individualized, prognostic information about implantation potential. 相似文献89.
Adequate pathologic slide preparation of percutaneous fine-needle biopsy (PFNB) specimens is necessary to maximize sensitivity and yield a tissue diagnosis. We present a quality control review of our biopsy technique and results in 71 aspiration biopsies done in 59 patients. Immediate cytology slide preparation in the radiology suite enabled us to increase our diagnostic yield from 53% to 84%, and allowed us to preserve PFNB, rather than open biopsy, as the primary diagnostic modality. We recommend regular review of biopsy techniques to confirm adequate diagnostic yields of these procedures. 相似文献
90.
L. A. Duke A. S. Breathnach D. R. Jenkins B. A. Harkis A. W. Codd 《Epidemiology and infection》1996,116(3):303-308
In an outbreak of gastroenteritis affecting 43 people, cryptosporidium and campylobacter were isolated from stool specimens and in two cases dual infection was found. All the cases had drunk unboiled water from a private untreated water supply. Investigations revealed the carcasses of three lambs in a collection chamber connected with the water supply, and these, or run-off of slurry from surrounding fields, were the presumed source of contamination. Issues relating to the maintenance and monitoring of private water supplies are discussed. Problems with such supplies include old piping, proximity of livestock, inadequate knowledge of the layout and limited resources for monitoring and maintenance. 相似文献