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排序方式: 共有1039条查询结果,搜索用时 15 毫秒
1.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
2.
Philip Steer 《BJOG : an international journal of obstetrics and gynaecology》2005,112(S1):109-112
Until recently, bioethics (ethics related to biology or, more specifically, in the context of preterm labour, medical ethics) was considered mainly to relate to the active treatment or investigation of patients. Collection of data, excised specimens or even whole organs was considered to be relatively uncontentious as it did not impinge directly upon the health of the individual concerned. However, in the UK in particular, the practice of collecting data, tissues or even whole organs has recently come under the spotlight of public scrutiny, particularly following the Alder Hey Enquiry. Coincidentally with a decline in public confidence in the probity of authority, medical scientists increasingly have to justify the accumulation of data about individuals. 相似文献
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One of the first decisions that needs to be taken when planning a birth cohort concerns the size of the study. This in turn will depend on the research questions to be answered and thence whether environmental exposures and outcomes are measured on a continuum or as dichotomous variables. Here we describe ways in which different birth cohorts have addressed this issue and explore the advantages of smaller detailed studies over larger less-detailed studies. 相似文献
5.
Reliability of DSM-III diagnoses for major depression and generalized anxiety disorder using the structured clinical interview for DSM-III 总被引:1,自引:0,他引:1
J H Riskind A T Beck R J Berchick G Brown R A Steer 《Archives of general psychiatry》1987,44(9):817-820
This study examined the interrater reliability of generalized anxiety disorder (GAD) and major depressive disorder (MDD) diagnoses derived from the Structured Clinical Interview for DSM-III (SCID). Using videotaped interviews, paired raters made independent diagnoses of 75 psychiatric outpatients. The percent agreement of the raters was 82% for MDD and 86% for GAD; the respective kappa values were .72 and .79. The results indicated that the SCID can be employed reliably to differentiate MDD from GAD. The SCID is recommended for further research with these disorders. 相似文献
6.
F. R. VOGELPOEL R. J. VAN KOOIJ E. R. TE VELDE J. VERHOEF 《International journal of andrology》1990,13(2):81-86
Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous. 相似文献
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P J Danielian A C Allman P J Steer 《British journal of obstetrics and gynaecology》1992,99(6):452-454
OBJECTIVES: To determine the perinatal outcome of fetuses who had birthweights less than that expected from early third trimester ultrasound scanning. DESIGN: Retrospective estimation of centile fetal weight at early third trimester ultrasound scanning compared with actual centile birthweight corrected for gestational age, parity and sex. SETTING: Teaching Hospital Obstetric Unit, London. SUBJECTS: 197 unselected women with singleton cephalic pregnancies who were delivered at term in our unit between October 1989 and May 1990. MAIN OUTCOME MEASURES: CTG abnormality, need for fetal blood sampling in labour, meconium-staining of the amniotic fluid, mode of delivery, Apgar scores at 1 and 5 min, need for transfer of baby to neonatal unit, and need for neonatal intubation of the neonate at delivery. RESULTS: An actual birthweight greater than 5% less than the birthweight estimated from ultrasound scanning identified 44 babies (22%) with an increased risk of CTG abnormalities (chi 2 = 8.38, P less than 0.0025; Odds ratio (OR) = 2.54; 95% CI 1.36 to 4.78) and need for operative delivery (chi 2 = 5.81, P less than 0.0125; OR = 1.94; 95% CI 1.15 to 3.27), when compared with the remainder of the sample. Overall 14 (32%) of this group had birthweights above the 50th centile. A group of 44 babies selected as being the smallest for gestational age, without reference to growth pattern, had a similar excess morbidity. (All this group had birthweights below the 39th centile). CONCLUSIONS: This study supports the hypothesis that in-utero fetal growth pattern is as important for perinatal outcome as being small for gestational age per se. 相似文献