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Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction.  相似文献   
33.
AIM: To compare the accuracy of fast magnetic resonance (MR) imaging using the half-Fourier single shot turbo spin echo (HASTE) sequence with helical computed tomography (CT) in diagnosing bowel obstruction. MATERIALS AND METHODS: Prospective evaluation of 44 patients with clinical evidence of bowel obstruction was conducted using various investigations including HASTE MR and helical CT. MR was performed with a Siemens 1.5 Tesla MR Imaging System and CT was performed with one of two Siemens ARHP CT systems using helical technique. MR acquisition allowed data to be gathered in 6-10 minutes and no contrast media were administered. CT imaging consisted of consecutive helical CT through the abdomen and pelvis with oral and intravenous contrast medium used when indicated. Bowel dilation along with the presence and level of obstruction were determined. RESULTS: Twenty-eight patients had bowel obstruction confirmed at laparotomy or by radiographic assessment. Of these, 25 had small bowel obstruction and three had colonic obstructions. The obstruction was due to fibrous adhesions in nine patients, metastases or primary carcinoma in seven, Crohn's disease in four, hernias in two, and inflammation or abscess in two. Other causes of obstruction included lymphoma, intussusception and anastomotic stricture. The cause of obstruction was correctly diagnosed by CT in 71%, and by MR in 95% of cases. The sensitivity, specificity and accuracy for HASTE MR imaging was 95%, 100% and 96% respectively as compared to 71%, 71% and 71% for helical CT. CONCLUSION: Fast MR imaging using the HASTE sequence is more accurate than helical CT in diagnosing bowel obstruction.  相似文献   
34.

Background  

Adolescence is an important stage of life for establishing healthy behaviors, attitudes, and lifestyles that contribute to current and future health. Health risk behavior is one indicator of health of young people that may serve both as a measure of health over time as well as a target for health policies and programs. This study examined the prevalence and distribution of youth health risk behaviors from five risk behavior domains–aggression, victimization, depression and suicidal ideation, substance use, and sexual behaviors–among public secondary school students in central El Salvador.  相似文献   
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Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.   相似文献   
37.
Child Behaviour Checklist classification of behaviour disorder   总被引:1,自引:0,他引:1  
Objective : The aim of this study was to determine the applicability of the published clinical cut-off scores of the Child Behaviour Checklist (CBCL) for the classification of behaviour disorders.
Methodology : Child Behaviour Checklists were obtained for 1342 subjects newly referred to the six major mental health centres in Melbourne. The normative community sample of 1002 7-, 12- and 15-year-olds was drawn from a school-based asthma prevalence study.
Results : The mean total problem T-score for the children referred to mental health centres was 67 and was above the clinical range for all age groups. Using referral to psychiatric services as the gold standard, the sensitivity and specificity of the CBCL using a cut-off of ≥ 60, was 77.4 and 83.2%, respectively. This compares favourably with the sensitivity of 68% and specificity of 82% for the American sample. Using a cut-off score of ≥ 63, the sensitivity was 70.5% and the specificity was 88.6%. The referred and community samples differed with respect to socio-economic status, family structure and mothers' level of education. Fifty-two per cent of the clinically referred children lived with both parents, compared with 89% of the community sample.
Conclusions : While there are some limitations to this study in terms of both the clinic and community sample, support is provided for the usefulness and applicability of the recommended CBCL cut-off scores in an Australian population.  相似文献   
38.
Cocaine use in pregnancy in Amsterdam   总被引:1,自引:0,他引:1  
To study the effects of cocaine use in pregnancy in Amsterdam, clinical data on cocaine-using pregnant women ( n = 21) and their offspring ( n = 23) were obtained retrospectively (1987–1994) at the Academic Medical Center, Amsterdam. Infants exposed to cocaine had a median gestational age of 39 weeks and a median birth weight of 3090 g. There were six preterm infants, two small-for-gestational-age infants and five infants with a small head circumference. Three infants had a congenital malformation. One infant (Potter's syndrome) died shortly before birth. One infant had congenital syphilis, four had intracerebral abnormalities on ultrasound and four had abnormal neurologic symptoms in the neonatal period. One infant died after 21 days of life. At follow-up four infants showed abnormal development. In 12 of the 23 infants (52%), one or more possible effects of cocaine were found.  相似文献   
39.
Substance use in pregnancy: do we care?   总被引:3,自引:0,他引:3  
Two cohorts of substance-using women were compared retrospectively. From 1969 to 1979 a very high perinatal mortality rate (PMR 9.8%) was found among 92 polydrug-using women (1 twin excluded). Preterm delivery occurred in 25% of all pregnancies and in 30% of the children birth weight was below the 10th percentile. Nineteen women using heroin only had a worse fetal outcome (PMR 32%, preterm delivery in 47%, birth weight < 10th percentile in 42%). These results led to a strict surveillance system. In the period 1980–1989, 240 women (4 twins excluded) delivered after 16 weeks. Total fetal loss decreased to 2.1% and PMR to 0.4%, which was similar to results in controls. However, 22% of the women still delivered before 37 weeks and 27% delivered a child < 10th percentile. Methadone-using women were able to halve their dosage during pregnancy and 16 were detoxified. Multivariate analysis within the substance users of the second cohort showed that the neonatal abstinence syndrome, but not the (registered) amount of opiates used, was related to a lower birth weight. Not coping with prenatal care was related to a shorter pregnancy length. Multivariate analysis, including the controls, showed a significant relation of birth weight (345 g lower) with substance use. Also, head circumference was 0.8 cm smaller. Length of pregnancy however was related to smoking. This study shows that it is difficult to make substance users attend prenatal care, but also that women coping with prenatal care reduce substance intake. Opiate use might be responsible for lower birth weight, although not in a clear dose–response relationship, whereas lifestyle, as represented by not coping with prenatal care and the quantity of cigarette smoking, shortens the length of pregnancy.  相似文献   
40.
1. The subfornical organ, median preoptic nucleus and the organum vasculosum of the lamina terminalis (OVLT) are a series of structures situated in the anterior wall of the third ventricle and form the lamina terminalis. The OVLT and ventral part of the median preoptic nucleus are part of a region known as the anteroventral third ventricle region.
2. Data from many laboratories, using techniques ranging from lesions, electrophysiology, neuropharmacology, Fos expression, immunohistochemistry and receptor localization, indicate that the tissue in the lamina terminalis plays a major role in many aspects of body fluid and electrolyte balance.
3. The subfornical organ and OVLT lack the blood-brain barrier and detect alterations in plasma tonicity and the concentrations of circulating hormones such as angiotensin II and possibly atrial natriuretic peptide and relaxin.
4. This information is then integrated within the lamina terminalis (probably in the median preoptic nucleus) with neural signals from other brain regions. The neural output from the lamina terminalis is distributed to a number of effector sites including the paraventricular (both parvo- and magno-cellular parts) and supraoptic nuclei and influences vasopressin secretion, water drinking, salt intake, renin secretion, renal sodium excretion and cardiovascular regulation.  相似文献   
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