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971.
972.
The objective of this study is to compare the accuracy of sonographic estimation of fetal weight of macrosomic babies in diabetic vs non-diabetic pregnancies. All babies weighing 4,000 g or more at birth, and who had ultrasound scans performed within one week of delivery were included in this retrospective study Pregnancies with diabetes mellitus were compared to those without diabetes mellitus. The mean simple error (actual birthweight--estimated fetal weight); mean standardised absolute error (absolute value of simple error (g)/actual birthweight (kg)); and the percentage of estimated birthweight falling within 15% of the actual birthweight between the two groups were compared. There were 9,516 deliveries during the study period. Of this total 1,211 (12.7%) babies weighed 4,000 g or more. A total of 56 non-diabetic pregnancies and 19 diabetic pregnancies were compared. The average sonographic estimation of fetal weight in diabetic pregnancies was 8% less than the actual birthweight, compared to 0.2% in the non-diabetic group (p < 0.01). The estimated fetal weight was within 15% of the birthweight in 74% of the diabetic pregnancies, compared to 93% of the non-diabetic pregnancies (p < 0.05). In the diabetic group, 26.3 % of the birthweights were underestimated by more than 15 %, compared to 5.4% in the non-diabetic group (p < 0.05). In conclusion, the prediction accuracy of fetal weight estimation using standard formulae in macrosomic fetuses is significantly worse in diabetic pregnancies compared to non-diabetic pregnancies. When sonographic fetal weight estimation is used to influence the mode of delivery for diabetic women, a more conservative cut-off needs to be considered.  相似文献   
973.
干细胞移植在帕金森病治疗中的应用与进展   总被引:1,自引:0,他引:1  
目的:综述干细胞移植治疗帕金森病的机制与进展。资料来源:应用计算机检索Medline 2000-01/2006-12与干细胞移植治疗帕金森病相关的文章,检索词为“stem cell,Parkinson disease,transplantation”,限定文献语种为“English”;万方数据库2004/2007期间与有关文章,检索词为“干细胞,帕金森病,移植”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。选择所述内容与干细胞移植治疗帕金森病的机制及应用进展相关的文章,无论观察对象是实验动物还是患者全部纳入,重复的研究以近3年且发表在较权威杂志者优先。资料提炼:共收集到500余篇相关文献,52篇符合纳入标准,选用其中31篇作为本文参考文献。资料综合:干细胞能向特定神经细胞定向分化,并在动物模型身上取得明显的治疗效果,为干细胞移植治疗帕金森病带来了新的希望。另外,联合TH、胶质细胞源性神经营养因子基因治疗帕金森病,由于胶质细胞源性神经营养因子的神经营养作用和TH具有分泌多巴胺能神经递质的功能,既能提高脑内多巴胺水平,又能使多巴胺能神经元长期存活、阻止多巴胺能神经元变性,重建宿主神经通路。因此,把干细胞作为基因载体、进行干细胞移植联合多基因治疗,为帕金森病的治疗提供了新的思路。结论:目前大部分的干细胞治疗帕金森病的研究结论是基于动物实验的结果,它们能否在人类身上得到类似或更好的的结果,目前尚未可知,其分子机制、致瘤性及免疫排斥等问题还需进一步研究。  相似文献   
974.
姜惠玲  王景杰  黄裕新  张少玲  杨琦 《医学争鸣》2005,26(22):2111-2111
1 对象和方法成年雄性SD大鼠84只,清洁级,体质量(200±20) g. 置于安静、温暖(20℃)、避强光的环境中饲养. 随机均分成2组,每组42只; 再随机均分成7个亚组用于直肠顺应性检测,制定压力曲线.  相似文献   
975.

Background  

Chronic hepatitis B virus infection (HBV) is an important health problem in the Turkish community in the Netherlands, and promotion of screening for HBV in this risk group is necessary. An individually tailored intervention and a culturally tailored intervention have been developed to promote screening in first generation 16-40 year old Turkish immigrants. This paper describes the design of the randomized controlled trial, which will be used to evaluate the effectiveness of the two tailored internet interventions as compared to generic online information on HBV, and to assess the added value of tailoring on socio-cultural factors.  相似文献   
976.
Objective  To assess incidence of uterine rupture in scarred and unscarred uteri and its maternal and fetal complications in a nationwide design.
Design  Population-based cohort study.
Setting  All 98 maternity units in the Netherlands.
Population  All women delivering in the Netherlands between August 2004 and August 2006 ( n  = 371 021).
Methods  Women with uterine rupture were prospectively collected using a web-based notification system. Data from all pregnant women in the Netherlands during the study period were obtained from Dutch population-based registers. Results were stratified by uterine scar.
Main outcome measures  Population-based incidences, severe maternal and neonatal morbidity and mortality, relative and absolute risk estimates.
Results  There were 210 cases of uterine rupture (5.9 per 10 000 pregnancies). Of these women, 183 (87.1%) had a uterine scar, incidences being 5.1 and 0.8 per 10 000 in women with and without uterine scar. No maternal deaths and 18 cases of perinatal death (8.7%) occurred. The overall absolute risk of uterine rupture was 1 in 1709. In univariate analysis, women with a prior caesarean, epidural anaesthesia, induction of labour (irrespective of agents used), pre- or post-term pregnancy, overweight, non-Western ethnic background and advanced age had an elevated risk of uterine rupture. The overall relative risk of induction of labour was 3.6 (95% confidence interval 2.7–4.8).
Conclusion  The population-based incidence of uterine rupture in the Netherlands is comparable with other Western countries. Although much attention is paid to scar rupture associated with uterotonic agents, 13% of ruptures occurred in unscarred uteri and 72% occurred during spontaneous labour.  相似文献   
977.
Objective  To determine the risk of maternal mortality and serious maternal morbidity because of major obstetric haemorrhage in Jehovah's witnesses in the Netherlands.
Design  A retrospective study of case notes.
Setting  All tertiary care centres, general teaching hospitals and other general hospitals in the Netherlands.
Sample  All cases of maternal mortality in the Netherlands between 1983 and 2006 and all cases of serious maternal morbidity in the Netherlands between 2004 and 2006.
Methods  Study of case notes using two different nationwide enquiries over two different time periods.
Main outcome measures  Maternal mortality ratio (MMR) and risk of serious maternal mortality.
Results  The MMR for Jehovah's witnesses was 68 per 100 000 live births. We found a risk of 14 per 1000 for Jehovah's witnesses to experience serious maternal morbidity because of obstetric haemorrhage while the risk for the total pregnant population was 4.5 per 1000.
Conclusions  Women who are Jehovah's witnesses are at a six times increased risk for maternal death, at a 130 times increased risk for maternal death because of major obstetric haemorrhage and at a 3.1 times increased risk for serious maternal morbidity because of obstetric haemorrhage, compared to the general Dutch population.  相似文献   
978.
Gastroenterology in developing countries: Issues and advances   总被引:3,自引:1,他引:2  
Developing countries shoulder a considerable burden of gastroenterological disease. Infectious diseases in particular cause enormous morbidity and mortality. Diseases which afflict both western and developing countries are often seen in more florid forms in poorer countries. Innovative techniques continuously improve and update gastroenterological practice. However, advances in diagnosis and treatment which are commonplace in the West, have yet to reach many developing countries. Clinical guidelines, based on these advances and collated in resource-rich environments, lose their relevance outside these settings. In this two-part review, we first highlight the global burden of gastroenterological disease in three major areas: diarrhoeal diseases, hepatitis B, and Helicobacter pylori. Recent progress in their management is explored, with consideration of future solutions. The second part of the review focuses on the delivery of clinical services in developing countries. Inadequate numbers of healthcare workers hamper efforts to combat gastroenterological disease. Reasons for this shortage are examined, along with possibilities for increased specialist training. Endoscopy services, the mainstay of gastroenterology in the West, are in their infancy in many developing countries. The challenges faced by those se~ing up a service are illustrated by the example of a Nigerian endoscopy unit. Finally, we highlight the limited scope of many clinical guidelines produced in western countries. Guidelines which take account of resource limitations in the form of "cascades" are advocated in order to make these guidelines truly global. Recognition of the different working conditions facing practitioners worldwide is an important step towards narrowing the gap between gastroenterology in rich and poor countries.  相似文献   
979.
Background The impact of hepatitis C virus (HCV) infection in renal transplant patients is controversial and there are no data on the outcome of renal transplantation in this sub-group of Irish patients. Aim To examine the outcome of renal transplantation in patients with hepatitis C. Methods We examined the outcome of first grafts from renal transplant patients with hepatitis C antibody positive and compared them to a control group. During this period, 24 HCV positive patients received 33 grafts. All were treated with standard immunosuppression. Results Graft survival rate was less in the HCV positive cases (p=0.0087). Graft survival at 1 year was 75% in the HCV positive group versus 85% in the HCV negative group, 40% versus 62% at 5 years and 14% compared with 40% at 10 years. Patient survival was similar in both groups (p=0.78). Patient survival at 1 year was 96% versus 94%, 87% versus 80% at 5 years and 70% in both groups at 10 years. Conclusion In the Irish renal transplant population, the presence of hepatitis C antibodies, before or after transplantation is associated with worse long-term graft, but not patient survival.  相似文献   
980.
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