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31.
Objectives: To assess: (i) the size of placental transfusion following a 30 s delay in cord clamping following vaginal and Caesarean births; and (ii) the feasibility of delaying cord clamping in the labour ward and particularly in the operating theatre.
Methods: Fourty-six infants born at 26–33 weeks gestation were randomized to having the umbilical cord clamped either immediately or 30 s after birth. The venous haematocrit was measured at 1 and at 4 h of age.
Results: There were trends towards higher mean haematocrits in the infants following delayed clamping, but these were not significant either at 1 h (55±7.7 vs 52.9±7) or at 4 h of age (55±7 vs 52.5±7). The trends were more marked in the infants born by Caesarean section, and in those born at 26–29 weeks gestation.
Conclusions: A 30 s delay in cord clamping is feasible at both vaginal and Caesarean births, but does not lead to the predicted difference in infant haematocrit. Although physiological studies suggest that a placental transfusion of 15–20 mL/kg occurs within 30 s of delivery, these data suggest that future trials should either delay cord clamping for more than 30 s, or should alter the position of the infant in relation to the uterus in order to facilitate the transfusion. Delayed cord clamping is feasible at Caesarean section. 相似文献
Methods: Fourty-six infants born at 26–33 weeks gestation were randomized to having the umbilical cord clamped either immediately or 30 s after birth. The venous haematocrit was measured at 1 and at 4 h of age.
Results: There were trends towards higher mean haematocrits in the infants following delayed clamping, but these were not significant either at 1 h (55±7.7 vs 52.9±7) or at 4 h of age (55±7 vs 52.5±7). The trends were more marked in the infants born by Caesarean section, and in those born at 26–29 weeks gestation.
Conclusions: A 30 s delay in cord clamping is feasible at both vaginal and Caesarean births, but does not lead to the predicted difference in infant haematocrit. Although physiological studies suggest that a placental transfusion of 15–20 mL/kg occurs within 30 s of delivery, these data suggest that future trials should either delay cord clamping for more than 30 s, or should alter the position of the infant in relation to the uterus in order to facilitate the transfusion. Delayed cord clamping is feasible at Caesarean section. 相似文献
32.
Objective: To evaluate the incidence and severity of apnoea and bradycardia in hospitalized preterm infants following immunization at 2 months of age, and identify risk factors.
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTPw ) in the neonatal intensive care unit (NICU) at King George V Hospital Sydney. Half the infants also received Haemophilus influenzae type b conjugate vaccine (Hib) simultaneously. All infants were monitored for apnoea and bradycardia in the 24 h periods pre- and post immunization.
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTPw were less likely to have apnoea and/or bradycardia than those given DTPw alone.
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization. 相似文献
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTP
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTP
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization. 相似文献
33.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age. 相似文献
34.
This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background. 相似文献
35.
OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective. 相似文献
36.
A prospective study of methylenetetrahydrofolate reductase and methionine synthase gene polymorphisms, and risk of colorectal adenoma 总被引:8,自引:2,他引:8
Chen J; Giovannucci E; Hankinson SE; Ma J; Willett WC; Spiegelman D; Kelsey KT; Hunter DJ 《Carcinogenesis》1998,19(12):2129-2132
We examined the relationship between a functional polymorphism (667C--
>T, ala-->val) of the methylenetetrahydrofolate reductase gene
(MTHFR) and the risk of colorectal adenomas in the prospective Nurses'
Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR
val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval
(CI) 0.84-2.17] was not significantly associated with risk of adenomas.
This lack of association was observed for both small (RR = 1.36, 95% CI
0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore,
there was no significant interaction between this polymorphism and
consumption of either folate, methionine or alcohol. We also examined the
relationship of a newly identified polymorphism (asp919gly) of the
methionine synthase gene (MS) with the risk of colorectal adenomas in the
same population. The MS gly/gly polymorphism was also not significantly
associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70).
These results, which need to be confirmed in other studies, suggest that
the MTHFR val/val polymorphism, which has been previously inversely
associated with risk of colorectal cancer, plays a role only in a late
stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may
protect against malignant transformation in the subset of benign adenomas,
which may progress to malignancy.
相似文献
37.
Jonny K. Andersson Elisabeth Hansson-Olofsson Jón Karlsson Jan Fridén 《Journal of plastic surgery and hand surgery》2018,52(1):30-36
Objective: The total number and cost of wrist MRIs in the catchment area of the Västra Götaland Region in Sweden (population 1 723 000) during 1 year was analysed, together with the number and content of referrals.Methods: Six radiology departments reported the numbers and rate of all MRI investigations intended to diagnose wrist ligament injuries (n?=?411) and other injuries to the wrist.Results: The additional cost of the difference between MRIs and a clinical examination by a hand surgeon, plus indirect costs for patients with suspected wrist ligament injuries, was calculated as 957 000 euros.Conclusions: It is recommended that MRI should only be used in patients in whom there are clinical difficulties in terms of diagnosing wrist ligament injuries. It is suggested that patients with suspected wrist ligament injuries should be referred directly to an experienced hand surgeon, capable of performing a standardised wrist examination and, when needed, diagnostic arthroscopy and final treatment. The proposed algorithm for the diagnosis and treatment of suspected wrist ligament injuries presented in the present study could save time for the patient and for the radiology departments, as well as reducing costs. The ability to implement the early and appropriate treatment of acute ligament injuries could be improved at the same time. 相似文献
38.
Stevens T Phan S Frid MG Alvarez D Herzog E Stenmark KR 《Proceedings of the American Thoracic Society》2008,5(7):783-791
The pulmonary circulation represents a unique vascular bed, receiving 100% of the cardiac output while maintaining low blood pressure. Multiple different cell types, including endothelium, smooth muscle, and fibroblasts, contribute to normal vascular function, and to the vascular response to injury. Our understanding of the basic cell biology of these various cell types, and the roles they play in vascular homeostasis and disease, remains quite limited despite several decades of study. Recent advances in approaches that enable the mapping of cell origin and the study of the molecular basis of structure and function have resulted in a rapid accumulation of new information that is essential to vascular biology. A recent National Institutes of Health workshop was held to discuss emerging concepts in lung vascular biology. The findings of this workshop are summarized in this article. 相似文献
39.
Expression of smooth muscle-specific proteins in myoepithelium and stromal myofibroblasts of normal and malignant human breast tissue. 总被引:28,自引:0,他引:28 下载免费PDF全文
D Lazard X Sastre M G Frid M A Glukhova J P Thiery V E Koteliansky 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(3):999-1003
The expression of several differentiation markers in normal human mammary gland myoepithelium and in certain stromal fibroblasts ("myofibroblasts") associated with breast carcinomas was studied by immunofluorescence microscopy of frozen sections. Several antibodies to smooth muscle-specific proteins (smooth muscle alpha-actin, smooth muscle myosin heavy chains, calponin, alpha 1-integrin, and high molecular weight caldesmon) and to epithelial-specific proteins (cytokeratins, E-cadherin, and desmoplakin) were used to show that myoepithelial cells concomitantly express epithelial and smooth muscle markers whereas adjacent luminal cells express only epithelial markers. The same antibodies were used to establish that stromal myofibroblasts exhibit smooth muscle phenotypic properties characterized by the expression of all the smooth muscle markers examined except for high molecular weight caldesmon. In addition, both myoepithelium and myofibroblasts show a significant degree of heterogeneity in smooth muscle protein expression. Thus, myoepithelial cells and stromal myofibroblasts are epithelial and mesenchymal cells, respectively, which coordinately express a set of smooth muscle markers while maintaining their specific original features. The dual nature of myoepithelial cells and the phenotypic transition of fibroblasts to myofibroblasts are examples of the plasticity of the differentiated cell phenotype. 相似文献
40.
EH Gemmill DJ Humes JA Catton 《Annals of the Royal College of Surgeons of England》2015,97(3):173-179