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91.
A W Chow R Percival-Smith K H Bartlett A M Goldring B J Morrison 《American journal of obstetrics and gynecology》1986,154(1):120-126
The rate of vaginal colonization with Escherichia coli in 495 healthy women was 12% in a prospective study with use of selective media and semiquantitative culture techniques. Computer-assisted multivariate analysis revealed that vaginal E. coli was significantly associated with the menstrual phase of the cycle, prior use of antibiotics, use of diaphragm or cervical cap for contraception, history of previous urinary tract infection, and coisolation of Staphylococcus aureus that was positive for the toxic shock syndrome toxin-1 (p less than 0.05, multiple stepwise logistic regression analysis). No significant association was observed with tampon use or brand, other contraceptive methods, sexual activity, genital symptoms, recent vaginal infection, or other personal habits. Quantitative cultures obtained sequentially throughout the menstrual cycle in 12 unselected women confirmed higher E. coli counts in menstrual or midcycle samples compared to paired premenstrual specimens (p less than 0.05, Wilcoxon paired rank sign test). These data emphasize the hormonal and other host determinants in vaginal colonization by E. coli and may explain the high rate of vaginal E. coli (64%), in addition to toxicogenic S. aureus, in acute toxic shock syndrome and the higher incidence of urinary tract infection in women with diaphragm or cervical cap for contraception compared to other contraceptive methods. 相似文献
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RM Subramaniam J Sherriff K Holmes MC Chan B Shadbolt 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):442-446
This study was conducted to establish clinicians’ perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty‐six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost‐effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups. 相似文献
96.
Induction of oxidative DNA base damage in human skin cells by UV and near visible radiation 总被引:11,自引:2,他引:11
The premutagenic oxidative DNA base damage, 7,8-dihydro-8-oxoguanine, is
induced in human skin fibroblasts by monochromatic radiation ranging from a
UVB wavelength (312 nm) up to wavelengths in the near visible (434 nm). The
oxidative damage is not generated by absorption of radiation in DNA but
rather by activation of photosensitizers generating genotoxic singlet
oxygen species. The spectrum for the yield of the oxidative damage in
confluent, non-growing, primary skin fibroblasts shows that it is UVA
(above 334 nm) and near visible radiations which cause almost all of this
guanine oxidation by natural sunlight in the fibroblast model. We estimate
that the total amount of oxidation of guanine induced by sunlight in
fibroblasts in the epidermis of the skin equals or exceeds the amount of
the major type of direct DNA damage, cyclobutane pyrimidine dimers. In
rapidly dividing lymphoblastoid cells, no oxidative guanine damage was
induced. However, in melanoma cells almost as much damage as in non-growing
fibroblasts (1.1 per 10(4) guanine bases after 1200 kJ/m2 UVA) was found.
We conclude that oxidative DNA base damage can probably contribute to the
induction of both non-melanoma and melanoma skin cancer by sunlight.
相似文献
97.
Immunological and functional protein S, protein C and antithrombin III levels and anticoagulant responses to activated protein C were measured in 24 patients with stroke in childhood. No hereditary deficiencies were found. The protein S levels in healthy controls of younger age did not differ from the adult levels. For optimal screening of protein S deficiency, measurements using functional as well as immunological assays are recommended. Appropriate criteria for the diagnosis of the deficiencies must be carefully applied if unnecessary anxiety and inappropriate treatment of children are to be avoided. 相似文献
98.
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
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