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101.
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Judith M. Yates BA DipEd Psych RN RM Judith Lumley MA MB BS PhD Grad Dip Child Dev FAFPHM Robin J. Bell MB BS PhD MPH FAFPHM 《The Australian & New Zealand journal of obstetrics & gynaecology》1995,35(4):375-379
Summary: A statewide study to ascertain the number of ultrasound scans received by women in pregnancy, to identify the proportion having a scan at 16 to 20 weeks' gestation, and to establish where the scan at 16 to 20 weeks was performed was carried out between January, 1991 and June, 1992 in Victoria. Additional data were collected by midwives and entered on the perinatal morbidity statistics form routinely completed for all births. Of 52,319 women providing responses, 3.1% did not have a scan. Of the remaining 96.9% who had a scan, 73.5% were scanned at 16 to 20 weeks'gestation. Predictors of not having a scan were maternal birthplace and higher parity: previous perinatal death(s), and attendance at nonteaching hospitals predicted the opposite. Predictors of being scanned were location of hospital (country), maternal birthplace, higher parity and maternal age (< 20 years). Substantial differences in frequency and timing were found between hospitals attended. Factors associated with the pattern of scanning are not readily explicable in terms of risk of malformations or women's choices. 相似文献
103.
M Stronati MG Revello RM Cerbo M Furione G Rondini G Gerna 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(3):340-341
104.
Chris E. East BApplSc RN RM DipAppl Sc Midwife Researcher Joan Webster BA RN RM Assistant Director of Nursing 《Midwifery》1995,11(4)
Objective: to determine whether the incidence of perineal outcomes, including episiotomy, at the Royal Women's Hospital (RWH) Brisbane reflected trends reported in the literature.Design: retrospective record review.Setting: RWH Brisbane.Participants: 953 women who delivered vaginally at the RWH in 1986 and 1992.Measurements and findings: there was a decline in the episiotomy rate from 65% in 1986 to 36% in 1992. This was accompanied by an increase in the incidence of intact perinea and spontaneous perineal tears. There was no difference in the incidence of spontaneous third degree tears. The decline in the incidence of episiotomy was found when other factors, such as parity, were considered, with the exception of operative vaginal delivery, where no difference in the use of episiotomy was found. There was no significant increase in the number of babies with an Apgar score of <7 at one minute of age, despite a significant reduction in the use of episiotomy when delivering these babies (55% in 1986 and 19% in 1992; P<0.001). The second stage was significantly longer in 1992 (P<0.01).Key conclusions: the findings reflect the decline in the incidence of episiotomy reported in the literature. This decline in rate was accompanied by an increase in the length of second stage and in the incidence of both intact perinea and perineal tears. Lowering the incidence of episiotomy did not result in a rise in the rate of babies with an Apgar score of <7 at one minute. 相似文献
105.
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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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
110.
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.
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