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81.
Objectives  The objectives of this study were to define the components of a skilled low-cavity non-rotational vacuum delivery (occiput anterior, vertex at station +2 or below and less than 45-degree rotation from midline) and to facilitate the transfer of skills from expert to trainee obstetricians.
Design  Qualitative study using interviews and video recordings.
Setting  Two university teaching hospitals (St Michael's Hospital, Bristol, and Ninewell's Hospital, Dundee).
Participants  Ten obstetricians and eight midwives identified as experts in conducting or supporting operative vaginal deliveries.
Methods  Semi-structured interviews were carried out using routine clinical scenarios. The experts were also video recorded conducting low-cavity vacuum deliveries in a simulation setting. The interviews and video recordings were transcribed verbatim and analysed using thematic coding. The anonymised data were independently coded by three researchers and compared for consistency of interpretation. The experts reviewed the coded interviews and video data for respondent validation and clarification. The themes that emerged following the final coding were used to formulate a list of skills.
Main outcome measures  Key technical skills of a low-cavity non-rotational delivery.
Results  The final list included detailed technical skills required for conducting a low-cavity vacuum delivery. The combination of semi-structured interviews and simulation videos allowed the formulation of a comprehensive skills tool for future evaluation.
Conclusion  This explicitly defined skills list could aid trainees understanding of the technique of low-cavity vacuum delivery. This is an important first step in evaluating clinical competence in intrapartum procedures.  相似文献   
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在一项随机、平行分组的开放试验中,27例妊娠糖尿病妇女(年龄30.7±6.3岁,HbA1c〈7%)随机分为门冬胰岛素治疗组(餐前5分钟注射)和常规人胰岛素治疗组(餐前30分钟注射)。试验时间为从诊断妊娠糖尿病(18~28周)至产后6周。研究期间两组的总体血糖水平均控制良好(试验开始和结束时HbA1c≤6%)。进餐试验时,试验6周时的平均血糖水平(门冬胰岛素组4.2±0.57mmol/L,常规人胰岛素组4.8±0.86mmol/L)略低于试验0周时(门冬胰岛素组4.9±0.59mmol/L,常规人胰岛素组5.1±0.36mmol/L)。  相似文献   
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Couper RT  Couper JJ 《Lancet》2000,356(9230):673-675
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Background: To determine the prevalence of Orbscan II‐derived keratoconus traits in relations of individuals with keratoconus and a control group and to apply these to a pedigree analysis. Methods: In a controlled, prospective, observational case series, four Orbscan II‐derived corneal parameters were examined in relations of individuals with keratoconus and a control group of low myopes (<2.5 D). The four parameters and thresholds for abnormality (derived from a literature review) were as follows: average keratometry (≥47.2 D), I‐S value (≥1.2 D), posterior float apex (≥42 µm) and thinnest pachymetry (≤463 µm). Results: Forty‐four unrelated controls (88 eyes) and eight families with 90 members without known (178 eyes) and 11 members with keratoconus (19 eyes) were analysed. One of 88 (1.14%) control eyes had a single keratoconus trait, and none had more than one trait. Of 178 eyes from relatives of patients with keratoconus, 45 (25.3%) had one or more keratoconus traits. Relatives of patients with keratoconus had an elevated risk of possessing a keratoconus trait (relative risk 14.67, CI 2.07–104.07, P < 0.001) compared with controls. Approximately 53.3% of relatives with a keratoconus trait were evident on either pachymetric or posterior elevation indices alone. Six of eight families suggested dominant inheritance. Conclusions: Keratoconus traits are common in relatives of patients with keratoconus. There prevalence may have been previously underestimated by using placido image‐based topography alone where corneal pachymetry and posterior elevation are not assessed. This study suggests an autosomal dominant pattern of inheritance with variable expressivity in some families.  相似文献   
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BACKGROUND: Several investigators have suggested that drinking cessation occurs because of poor health which may bias studies on the benefit or risk of alcohol consumption. METHODS: Drinking status, level of alcohol consumption, and two measures of health (perceived health and physician diagnosed chronic disease status) were determined from exams 1 (1987-1989) and 3 (1993-1995) on 12,562 African- and European-American participants, who were aged 45-64 years at exam 1 in the ARIC Study. For those in good health at exam 1, logistic regression analyses were used to model the association between health decline and drinking change at exam 3. RESULTS: Among the total population, drinking cessation was significantly more common among those who reported poor health at exam 3, and nondrinkers were unlikely to begin drinking regardless of exam 3 health. Using different measures of health status resulted in associations whose strength and significance varied with ethnicity and, in some cases, by gender. CONCLUSION: While the current data do not prove that the health decline occurred prior to drinking cessation, our findings support the hypothesis that poor health results in drinking changes which could potentially bias studies of alcohol's benefit and risk even when lifetime abstainers are used as the reference group.  相似文献   
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Because cystic fibrosis (CF) epithelia have ion transport abnormalities that may in part be regulated by intracellular calcium metabolism, and the kidney is actively involved in both ion transport and calcium homeostasis, we have investigated renal calcium handling in CF. Twenty-four-hour urine collections were analyzed in 34 CF patients (age 5 to 35 years) and kidney ultrasound studies were performed in 17 CF patients (age 6 months to 23 years). Renal histologic findings at postmortem examination of 14 CF patients (age 4 months to 23 years) were compared with those of 12 patients (age 11 months to 17 years) with other chronic illnesses (6 congenital heart disease, 6 malignancy). In 30 of the 34 CF patients urinary calcium excretion was normal (less than 4 mg (0.1 mmol)/kg/24 hr). Four CF patients had hypercalciuria (calcium excretion 4.4 to 8.8 mg (0.11 to 0.22 mmol)/kg/24 hr). However, these patients had other possible explanations for hypercalciuria, such as immobilization (n = 2), increased dietary sodium load (n = 1), and glucocorticoid therapy (n = 1). None of the 17 patients examined by renal ultrasonography had nephrocalcinosis. Five CF patients had histologic evidence of sparse nephrocalcinosis at autopsy. However, 6 of 12 autopsy kidney specimens from patients with other chronic illnesses and similar preterminal events also showed nephrocalcinosis. The hypercalciuria and nephrocalcinosis in CF and other chronic debilitating diseases may be explained by factors known to affect calcium handling. Our evidence does not support a primary renal defect as the basis of hypercalciuria and nephrocalcinosis in CF.  相似文献   
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