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1.
Objective To provide a valid estimate of singleton neonatal mortality based on birthweight and gestational age at delivery.
Design Record linkage of maternity data and neonatal mortality data.
Setting Scotland, UK.
Population All singleton preterm deliveries from 24 to 36 weeks inclusive between 1985 and 1994.
Main outcome measure Neonatal death.
Results There were 625,646 liveborn singleton deliveries over the study period, of which 33,912 were preterm (5.4%). The overall neonatal mortality in the preterm group was 41/1000 and the data have been presented by both gestational age and birthweight. The neonatal mortality rate fell with advancing gestation from 795/1000 live births at 24 weeks to 9/1000 live births at 36 weeks and was higher at the extremes of birthweight for a given gestational age. There was a significant increase in the proportion of babies delivered iatrogenically over the study period (χ test for trend   P < 0.001  ).
Conclusion This is the largest recent series to consider neonatal mortality using both birthweight and gestational age. These figures will be of use in obstetric management when elective preterm delivery is considered, and for providing prognostic guidance following preterm delivery.  相似文献   
2.
Objective To define the metabolic profile of postmenopausal hormone replacement therapies when delivered through gels, patches, implants or other non-oral routes. Such information may be useful in the absence of reliable clinical data on the effects of these therapies on the risk of cardiovascular disease.
Design and methods Selective literature review.
Patients Postmenopausal women.
Results Non-oral oestrogen therapies fail to invoke the hepatic response associated with oral therapy. Changes in hepatic protein synthesis are minimal and so plasma levels of binding globulins and other proteins tend to be normal. Many of the perturbations of the haemostatic system seen with oral therapy are avoided. In the absence of hepatic over-synthesis of apolipoproteins, plasma lipoprotein levels are unchanged or reduced. The direct effects of oestrogen on vascular function are apparent when the hormone is administered non-orally.
Conclusions The net effect of non-oral oestrogen therapies on the risk of cardiovascular disease is difficult to predict on the basis of current data. Some changes in plasma lipoprotein levels, such as the reduced fasting levels of triglycerides, would be considered desirable, but the cardioprotective increase in levels of high-density lipoproteins is absent. The differential effect on haemostasis markers is promising, but preliminary data relating to transdermal patches fail to support the idea that non-oral therapies will avoid the increased risk of venous thromboembolism associated with oral therapy. The ability of non-oral therapies to improve vascular function implies that they will offer postmenopausal women at least some of the cardiovascular protection seen with oral therapy.  相似文献   
3.
Objective To measure auto-antibodies against oxidatively modified low density lipoprotein (LDL) in pre-eclamptic pregnancies using two different techniques.
Design Clinical study comparing pre-eclamptic and normal pregnancies.
Setting Tampere University Hospital, Finland.
Population Twenty-one primigravidae with pre-eclampsia and 13 healthy, normotensive primigravidae as controls.
Methods The serum titers of antibodies against both malondialdehyde-modified and copper-oxidised LDL (MDA-LDL and copper-ox LDL) were analysed and related to parameters reflecting the severity of pre-eclampsia.
Results There was a positive correlation (   r = 0.58  ) between antibodies against MDA-LDL and copper-ox LDL in women with pre-eclampsia but not in healthy pregnant controls. The antibody levels against copper-ox LDL, but not against MDA-LDL, were higher in women with pre-eclampsia than in women with a normal pregnancy (   P < 0.01  ). While the antibody titers against copper-ox LDL did not correlate with any parameter reflecting the severity of pre-eclampsia, those against MDA-LDL showed a positive correlation with the level of diastolic blood pressure (   r = 0.54  ) and a negative correlation with platelet count (   r = 461  ) in women with pre-eclampsia.
Conclusions There are increased titers of serum autoantibodies against copper-oxidised LDL in pre-eclampsia, which may reflect enhanced lipid peroxidation involving circulating lipoproteins.  相似文献   
4.
Objective To assess the risk of maternal osteoporosis associated with antenatal corticosterioid administration for neonatal respiratory distress syndrome prophylaxis.
Design Prospective longitudinal study.
Setting Maternity unit of Chelsea and Westminster Hospital, London.
Population Fourteen pregnant women who received dexamethasone therapy for fetal lung maturation in anticipation of delivery before 34 completed weeks of gestation.
Methods Blood samples were collected before dexamethasone administration, 24 hours and 48 hours after the course of dexamethasone, and within 24 hours of delivery. Serum levels of carboxy terminal pro-peptide of type I pro-collagen (PICP) were measured to monitor the rate of bone formation, and serum levels of cross-linked carboxy terminal telopeptide (ICTP) were measured as a marker of bone resorption.
Main outcome measures Changes in the markers of bone turnover following dexamethasone administration.
Results Serum PICP levels dropped 24 hours after dexamethasone therapy (   P = 0.001  ), but partially recovered by 48 hours (   P = 0.014  ) to reach higher than pre-therapy levels at delivery (   P = 0.044  ). Although there were no corresponding changes in the serum levels of ICTP after 24 and 48 hours of therapy, levels increased from pretherapy to delivery (   P = 0.006  ).
Conclusion Antenatal corticosteroid therapy leads to a transient suppression of, followed by an increase in, bone formation without any significant alteration in the pattern of bone resorption expected during pregnancy.  相似文献   
5.
We report the case of a 34-year-old woman with severe post-infectious gastroparesis who was transferred from an outside medical facility for a second opinion regarding management.This patient had no prior history of gastrointestinal symptoms.However,in the aftermath of a viral illness,she developed two months of intractable nausea,vomiting,and oral intake intolerance that resulted in numerous hospitalizations for dehydration and electrolyte disturbances.A solid-phase gastric emptying scan had confirmed delayed emptying,confirming gastroparesis.Unfortunately,conventional pro-kinetic agents and numerous anti-emetic drugs provided little or no relief of the patient’s symptoms.At our institution,the patient experienced a cessation of vomiting,reported a significant reduction in nausea,and toler-ated oral intake shortly after taking mirtazapine.Based on mirtazapine’s primary action as a serotonin(5-HT)1a receptor agonist,we infer that this receptor system mediated the clinical improvement through a combination of peripheral and central neural mechanisms.This report highlights the potential utility of 5-HT1a agonists in the management of nausea and vomiting.We conclude that mirtazapine may be effective in treating symptoms associated with non-diabetic gastroparesis that are refractory to conventional therapies.  相似文献   
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The selenium status of children with phenylketonuria on a synthetic low phenylalanine diet was assessed. Correlation between blood selenium and red cell glutathione peroxidase was unsatisfactory ( r = 0.65) due to the poor discrimination of red cell glutathione peroxidase with a low selenium diet. No symptoms of deficiency were observed. Supplementation with 50 μg per week of selenium as brewers yeast tablets over a period of 6 months significantly increased the blood selenium of the phenylketonuric children. Plasma Vitamin E levels were within normal limits. The supplementation effectively doubled their selenium intake to 15–17 μg per day, which is probably sufficient for this group with an adequate Vitamin E status, though considerably lower than the recommended minimum intake of 50 μg per day.  相似文献   
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Objective To determine the relation between the inactive urinary kallikreimcreatinine ratio (IUK:Cr) and the angiotensin sensitivity test (AST) at 28 weeks of gestation and to assess each as a screening test for pre-eclampsia.
Design Prospective interventional study.
Subjects Four hundred and fifty-nine normotensive nulliparous women recruited from hospital antenatal clinics.
Setting John Radcliffe Maternity Hospital, Oxford, and Queen Charlotte's and Chelsea Hospital, London.
Interventions A urine sample for IUK:Cr measurement was provided before performing the AST at 28 weeks of gestation. Those women who demonstrated increased sensitivity to angiotensin II were entered into a randomised placebo controlled trial of low dose aspirin for the prevention of pre-eclampsia (CLASP).
Main outcome measures The development of pre-eclampsia.
Results The IUK:Cr ratio was significantly lower in those women who showed increased sensitivity to angiotensin II (   P < 0.0001  Student's t test). The sensitivity and specificity for detecting pre-eclampsia were, respectively, 22% and 85% for the AST and 67% and 75% for the IUK:Cr. Low-dose aspirin (60 mg) had no effect on the pregnancy outcome.
Conclusion There appears to be some relation between the IUK:Cr and AST tests in pregnancy. However, in this population, the IUK:Cr ratio was a better screening test for pre-eclampsia than the AST, but overall neither test was a powerful predictor for the syndrome.  相似文献   
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