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Objective: to compare teenagers who become unintentionally pregnant and teenagers who have never been pregnant but are using contraception on matters related to family/partner stability, and communication with a parent or stable sexual partner about sexual matters.Design: survey utilising self-completed questionnaire.Setting: a hospital antenatal clinic and community-based family planning clinic.Participants: 30 teenagers with an unplanned pregnancy and 31 ‘never-pregnant’ teenagers using contraception.Findings: the two groups were similar on demographic factors, mean age at which sexual intercourse was first experienced, total number of sexual partnerships, the number of teenagers having a current, regular boyfriend and mean length of the interval between when the teenagers first started going out with their boyfriend and when first sexual intercourse took place. Teenagers in the family planning clinic group were more likely to be living with both natural parents and to be still at school or in higher education. The mean length of time pregnant teenagers had been going out with their boyfriend was longer, they were more likely to be cohabiting with him and to be unemployed. Participants from the antenatal clinic group communicated more with their mothers about sexual matters than those in the family planning clinic group, who were more likely to seek this information from books. The family planning clinic participants were more likely to discuss personal rules and values with friends than those in the antenatal clinic group.Implications for practice: to develop understanding of factors predisposing to unplanned pregnancy during adolescence and to implement measures to counter them, further studies to examine the influence of teenagers' perceptions of family relationships and future life prospects on contraception use and unplanned pregnancy were identified.  相似文献   
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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   
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Kvam  E; Tyrrell  RM 《Carcinogenesis》1997,18(12):2379-2384
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   
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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   
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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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