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1.
CJ Schorah 《Canadian Metallurgical Quarterly》1998,351(9105):834; author reply 834-834; author reply 835
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Prepregnant weight in relation to risk of neural tube defects   总被引:1,自引:0,他引:1  
OBJECTIVE: To examine the relation between prepregnant weight and the risk of neural tube defects (NTDs). DESIGN: Data were collected from 1988 to 1994 in a case-control surveillance program of birth defects. SETTING: Study subjects were ascertained at tertiary care centers and birth hospitals in the greater metropolitan areas of Boston, Mass, and Philadelphia, Pa, and in southeastern Ontario. PARTICIPANTS: Cases were 604 fetuses or infants with an NTD identified within 6 months of delivery. Controls were 1658 fetuses or infants with other major malformations identified within 6 months of delivery. For 1992 to 1994, there were 93 control infants without major malformations. MAIN OUTCOME MEASURE: Relative risk of NTDs in infants or fetuses for different maternal weights. RESULTS: Relative to women who weighed 50 to 59 kg, risk of NTDs increased from 1.9 (95% confidence interval [CI], 1.2 to 2.9) for women weighing 80 to 89 kg to 4.0 (95% CI, 1.6 to 9.9) for women weighing 110 kg or more. When women were classified according to daily intake above or below the recommended level of 400 micrograms of folate, approximate threefold increases in risk were estimated for the heaviest weights in both groups. Intakes of 400 micrograms of folate or more reduced risk of NTDs by 40% among women weighing less than 70 kg, but no risk reduction was observed among heavier women. CONCLUSION: The risk of NTDs increased with increasing prepregnant weight, independent of the effects of folate intake.  相似文献   

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The ability to hydrolyse and absorb pteroylpolyglutamates (PteGlun) included in a standard meal in mothers who had given birth to an infant with a neural tube defect was tested by comparing them with mothers who had not had any infants with this defect. When compared with control mothers working in the research unit in which the study was performed, case mothers had significantly lower baseline serum and erythrocyte folate levels, and smaller increases in serum folate following the meal containing PteGlun. However, all estimates of folate were similar when case mothers were compared with a group of mothers who were friends of the case mothers. The results show that the higher the baseline levels of serum and erythrocyte folate the greater the increase in serum folate after the test meal. Fitting a model for the serum folate response curve resulted in coefficients which differed significantly between case mothers and all control mothers. We conclude that intestinal hydrolysis of PteGlun taken orally is not impaired in mothers who have had infants with neural tube defects when compared with control mothers with similar baseline folate levels, although the curves describing the response to the meal for the two groups do differ significantly. Further investigation is required to determine the mechanism underlying this difference.  相似文献   

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The disturbances of blood platelet activity play an important role in the formation of haemostasis disorders in patients with end-stage renal failure (ESRF). Phospholipids and their fatty acids play an essential role in the structure and function of the platelet. In patients with ESRF, changed lipid metabolism and also changed platelet phospholipid composition are observed. Data is available on the positive influence of recombinant human erythropoietin (rHuEPO) on some lipid metabolism disorders in patients with ESRF. The aim of this study was to demonstrate the influence of rHuEPO on the fatty acid composition of platelet phospholipids in patients with ESRF treated with repeated haemodialysis. The study material included 25 patients divided into two groups: group I--14 patients treated with repeated haemodialysis, group II--11 patients also treated with haemodialysis in whom rHuEPO was administered subcutaneously in doses 2000 U twice weekly. In group I great differences in fatty acid composition were noted in comparison to the control group. In general, decreased content of unsaturated fatty acids was found in all phospholipid classes, except for phosphatidylcholine. In group II the changes in fatty acid composition were considerably less pronounced than in group I, in the case of many acids reaching the values observed in the control group. The obtained results suggest that rHuEPO improves changed platelet lipid metabolism in patients with ESRF treated with repeated haemodialysis.  相似文献   

8.
Abnormal marrow signal and marrow enhancement have not been described in association with benign avulsive cortical irregularity. We present the case of an 11-year-old gymnast with such findings that partially resolved over time. The marrow MR abnormalities are believed to represent an extension or spectrum of findings associated with avulsive cortical irregularity, and should not instantly suggest infection or malignancy, as has been previously indicated. Careful and close clinical and radiological follow-up is required to confirm its benign course.  相似文献   

9.
The Magdeburg Register of birth defects includes information on the incidence rate of neural tube defects (NTD) in the city of Magdeburg since 1980, and in the Regierungsbezirk (administrational district) since 1987. The average prevalence of NTD was 16.4 per 10,000 births in the city of Magdeburg, and 12 per 10,000 births in the surrounding counties. Besides of this significant difference between the city and counties, there are conspicuous variations from one year to the next. In 1987 the prevalence of NTD was about 27 per 10,000 births in the city of Magdeburg whereas the observed prevalence in the countryside was about 19 per 10,000 births. Different eating habits and/or increased teratogenic influences in the city may be considered as causes. In 1997 there was also a high rate of incidence of NTD in the city of Magdeburg--16.4 per 10,000 births. The incidence rate of NTD in the counties (about 10 per 10,000) births) is again lower than in the city. Because of these incidence rates, we may assume that the examined population is insufficiently protected by folic acid in the preconceptional stage.  相似文献   

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OBJECTIVE: To determine the relation between blood folic acid and serum vitamin B12 in neural tube defect pregnancies using data from the MRC Vitamin Study and a literature review of all studies. DESIGN: Stored blood samples collected as part of a randomised trial of vitamin supplementation in the prevention of neural tube defects were retrieved from affected pregnancies (cases) and unaffected pregnancies (controls). Four controls were matched with each case by centre, maternal age and duration of storage of the blood sample. The samples had been collected from women at entry to the trial, immediately before the women became pregnant, and at around 12 weeks of pregnancy. Our results were combined with those already published from other studies to obtain an overall assessment of blood folic acid and vitamin B12 in relation to neural tube defects. SETTING: Blood samples were collected as part of the MRC Vitamin Study. The collaborating centres were in the United Kingdom, Hungary, Israel, Australia, Canada and Russia. PARTICIPANTS: Twenty-seven women with neural tube defect pregnancies and 108 matched controls with unaffected pregnancies. RESULTS: Serum and red cell folic acid and serum vitamin B12 levels were lower in the cases than in controls at each of the three occasions when blood samples were collected, but no comparison was significant (P > 0.05). A systematic review of all studies from the literature showed that on average, during the 1st trimester of pregnancy, serum folic acid was 0.6 ng/ml lower in neural tube defect pregnancies (P < 0.01), red cell folic acid was 77 ng/ml lower (P < 0.001) and serum vitamin B12 was 38 ng/l lower (P < 0.001). A logistic regression showed no association between serum B12 and neural tube defects after allowing for serum folic acid. CONCLUSION: our results are consistent with other evidence that folic acid and vitamin B12 levels are lower in women with neural tube defect pregnancies and consistent with evidence from randomised trials which showed that folic acid is protective.  相似文献   

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A number of studies on sexual differences in the ilium have been reported. However, most of these studies have focused on the adult ilium. With regard to sexual differences in the fetal ilium, few studies have been carried out. Especially, there have few studies regarding sexual differences in the fetal ilium using dry bones. In the present study, sexual differences in the morphological characteristics of the greater sciatic notch were investigated using dry fetal iliac bones. We examined 212 fetuses (106 males and 106 females) measuring 20.0 cm or more in fetal length with free of gross malformations or deformities which were collected at Saga Medical School. The iliac bones were excised from these fetuses and dried as materials for study. Fetal length was measured in the fully extended position and was classified into six groups each for males and females in 5-cm increments, giving a total of twelve groups. The inner lateral surface of the greater sciatic notch was magnified 25x using projector, traced, and the tracings were inputted to a computer (7600/120: Apple Co. Ltd) using a flatbed scanner. The width and height of the greater sciatic notch were measured, as well as the area of the greater sciatic notch. No sexual differences were noted regarding the increase in the width of the greater sciatic notch in fetuses up to 39.9 cm in fetal length. In fetuses measuring between 40.0 anf 44.9 cm, a significant sexual difference was observed, with the increase in greater sciatic notch width markedly greater in females. With respect to the increase in the height of the greater sciatic notch, no significant differences were noted. No significant differences were observed in the total area of the greater sciatic notch in fetuses up to 39.9 cm in fetal length. On the other hand, a significant sexual difference was observed in fetuses measuring 40.0 cm or more, with the total area markedly increased in females. In addition, no significant differences were found in the area between the two sides of the greater sciatic notch in fetuses up to 39.9 cm in fetal length, although significant differences were observed in fetuses measuring 40.0 cm or more. In female fetuses 40.0 cm or more in fetal length, the greater sciatic notch was found to be wider than in males, and the peak of the greater sciatic notch was displaced in the anteroinferior direction, farther from the auricular surface of the ilium and nearer the pubic bone. Thus these female fetuses show morphological characteristics of the adult female pelvic bone. Based on the results obtained, it is concluded that sexual differences can be identified in fetuses from the 8th month of pregnancy (fetal length 40.0 cm or more).  相似文献   

12.
OBJECTIVE: To examine the causes and mortality of poisoning in Tehran. METHODS: The 7000 poisoning cases referred to Loghman-Hakim Hospital in Tehran over six months in 1994 were evaluated retrospectively. RESULTS: The overall female to male ratio was 1.8:1. Most poisonings occurred in the age range 2-6 y for children and 21-40 y for adults. Oral ingestion was the most common route of intoxication. In children, boys had a higher frequency of poisonings than girls. Most cases of children were referred to the hospital between 8 am and 8 pm. In adults referred to the hospital, there was little diurnal variation in poisoning presentations. In adults, drugs were the most common cause of intoxication (60.2%). Of these, benzodiazepines (24.5%) were the most frequent, followed by antidepressants (20.5%) and analgesics (18%). Pesticide and opiate intoxications were also commonly observed. In children, after drugs (32.1%), hydrocarbons were the most frequent cause of poisoning (19.2%). Pesticide poisonings were most often fatal (19.2%), followed by barbiturates (18.6%) and opiates (16.2%). Organophosphate insecticides were responsible for 57% of total pesticide poisoning cases. Of the deaths, 87.5% were attributed to suicide. CONCLUSION: The majority of poisoning cases in adults occur intentionally and in children accidentally.  相似文献   

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The authors carried out an epidemiological survey from october 12 to december 4, 1995, at Medina's mother and Child care centre (MCC) in Dakar in order to assess chemoprophylaxis among pregnant women in Dakar. The midwife/pregnant women ratio is 0.08 The mentioned diagnosis criteria were relevant regards to the references established for most of the answers because since the latter base malaria diagnosis on the following signs: fever, chills, headaches and vomiting. 64.6% of them assume compliance to antimalarial chemoporphylaxis. Education level seems to be the main determining factor in this trend. Although chloroquine is the most widely used drug, nevertheless 11.9% of pregnant women assuming compliance use it at inappropriate posology. Besides, pyrimethamine is used by 12.3% of them. 34% of pregnant women do show chloroquine in urine. The plasmodial index is 1.4%. Only 8.1% of these women are supplied by health centres where shortages are noted.  相似文献   

14.
Administered the Bayley Scales of Infant Development at 6 mo and the Stanford-Binet Intelligence Scale at 3 yrs to 77 normal children. When each S was 6 mo old, the family was observed and interviewed using the Home Observation for Measurement of the Environment (HOME), a measure of the quality of stimulation in the early environment. A difference of 21 or more points between a S's 6-mo Bayley Mental Development Index score and 3-yr Stanford-Binet score was used to determine whether the S had increased, remained stable, or decreased in mental test performance. Multiple discriminant analyses were done using the 6 subscales of the HOME inventory to differentiate among increasers, nonchangers, and decreasers. Increases in test performance were related to 2 subscales, Maternal Involvement with Child and Provision of Appropriate Play Materials. Decreases were related to inadequate Organization of Physical and Temporal Environment. Results indicate that home environment may contribute to instability of performance on infant tests. Results are in agreement with the findings of R. B. McCall et al (see record 1975-04922-001) regarding gains for 21/2-17 yr olds, except that the parents' method of discipline may not be quite so important for infants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Fortification of flour with folic acid is simple, economical and safe. Failure to take appropriate regulatory action will mean that tens of thousands of women in Europe will needlessly continue to have pregnancies with neural tube defects.  相似文献   

17.
This study examined the stability of two aspects of infant visual attention derived from the paired-comparison procedure in infants tested at 6, 7, and 8 months: novelty preference and exposure time. Novelty preference, which reflects the relative amount of time the infants look at a new stimulus compared with a familiar stimulus, was found to be moderately stable, with cross-age correlations ranging from .30 to .50 when scores were averaged across six problems. Similar stability coefficients were found for counts of the number of problems for which infants exhibited novelty percentages exceeding an arbitrary criterion. Exposure-time scores, reflecting the time required to accumulate a preset amount of looking at the familiarization stimulus, also showed moderate stability, with cross-age correlations ranging from .32 to .38. These two measures of visual attention did not correlate well with one another and neither was related to contemporaneous measures of infant competence, represented by Bayley (1969) Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) scores at 7 months. It was concluded that novelty and exposure-time scores each reflect moderately stable but independent characteristics of infant behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
PURPOSE: Skin binding of prednisolone and its esters was investigated in the hairless mouse skin in vitro. METHODS: The distribution of the amount of drugs bound in the skin was determined by a skin slicing technique. The model drugs used were prednisolone (PN, M.W. 360) and its esters, senesyonate (PN-C5, M.W. 442), geranate (PN-C10, M.W. 510), farnesylate (PN-C15, M.W. 578), and geranylgeranate (PN-C20, M.W. 646). RESULTS: The distribution of bound drug was nonhomogeneous in the skin; the concentration of PN-C10 and PN-C15 in the skin increased gradually with the distance from the skin surface. The parent drug, PN, however, was hardly bound in the viable skin. CONCLUSIONS: These findings suggest that the prodrugs of prednisolone may prolong the dermal retention of the parent drug and minimize to delivery into the systemic circulation of the prodrug and metabolite.  相似文献   

19.
The pattern of anatomical features of the brain revealed by magnetic resonance imaging (MRI) is described in six patients incidentally identified as having acallosal brains. The complex of morphological features associated with complete agenesis of the corpus callosum included lateral displacement of slitlike anterior horns of the lateral ventricles (bullhorn-like shape), dilatation of the posterior horns of the lateral ventricles, absence of the septum pellucidum, lateral displacement of the cingulate gyri, complete separation of fornices and the presence of the anterior commissure and longitudinal callosal bundles (Probst's bundles). No compensatory enlargement of the anterior commissure was seen in the patients. The planimetrically measured cross-sectional areas of the anterior commissures were between 2.0 and 4.2 mm2 (mean 3.1) (in ten normal subjects they were 4.5, SD 0.4; range 3.8-5.2 mm2) and were reduced in four and normal in two patients. Inconstant morphological features were an absence of the posterior commissure and a radial pattern of the sulci and gyri on the medial aspect of the hemispheres. Conventional clinical testing revealed no abnormalities except a slight impairment of walking heel-to-toe in two patients. None of the patients had subjective restrictions of activities of daily life, which shows the efficacy of unknown compensatory processes.  相似文献   

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