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21.
We report the case of a 9-year-old boy with a spinal cord meningioma whose only manifestations were recurrent episodes of chest pain lasting for 2 years. This case shows that spinal cord meningioma should be considered among the possible causative factors of chronic chest pain in childhood. Chest pain, meningioma, spinal tumors  相似文献   
22.
23.
Time dependent memory decay   总被引:4,自引:0,他引:4  
BACKGROUND: To estimate the rate of time dependent memory decay, injury rates from three independent studies were compared. METHODS: The studies asked subjects to recall injuries during the previous 2 months, 12 months, or 10 years. RESULTS: The annual injury rates obtained were 108/1,000, 66/1,000, and 19/1,000, respectively. These rates are all significantly different from one another at the 0.05 level. CONCLUSIONS: Important methodological and demographic differences between the studies, such as those involving age, injury severity, and seasonality, were ruled out as causes of these differences. Results found in the literature for other studies are compared and contrasted. These data suggest that recall periods of greater than 2 months are likely to significantly underestimate injury rates.  相似文献   
24.
Objective : To determine the approach to identifying neonatal hypoglycaemia and the definition of neonatal hypoglycaemia used by neonatal paediatricians in Australian Level 3 neonatal intensive care units (NICU).
Methodology : A questionnaire was sent to the 101 neonatal paediatricians in the 22 Level 3 NICU in Australia asking their method of screening for, and definition of, neonatal hypoglycaemia.
Results : Responses were received from 70 neonatal paediatricians, including all 22 directors. A bedside glucose meter is used in 19 of 22 NICU to screen for hypoglycaemia, whilst one NICU uses a glucose analyzer and another NICU uses a visual colour comparison method. One NICU does not screen, but has blood glucose measured in a satellite laboratory. If the screening method suggests hypoglycaemia, 62 of 63 neonatal paediatricians proceed to blood glucose determination in a laboratory, mostly using plasma samples. Based on the laboratory measurement, the definition of neonatal hypoglycaemia ranged from <1.1 to 3.0 mmol/L.
Conclusions : The majority of neonatal paediatricians in Australian NICU screen for neonatal hypoglycaemia using a bedside glucose meter. There is a wide range in the definition of neonatal hypoglycaemia from <1.1 to 3.0mmol/L.  相似文献   
25.
The original article to which this Erratum refers was published in Phytotherapy Research 14(5) 2000, 344-346. Following the publication of this paper in the August 2000 issue of Phytotherapy Research (14(5):344-346), it has come to our attention that there is a misleading statement regarding conclusions cited from the work of Butterweck et al. 1998. The discussion in the recent PTR paper states that those authors are 'in favour of the hypothesis that the antidepressant activity is due to the hypericin only'. We wish to make it clear that this is not the case, and the Butterweck paper actually concludes that 'both naphthodianthrones must be considered as active constituents of the crude extract of H. perforatum. However, previous studies indicate that the other consitutuents of the crude drug also have activity'. The authors apologize for this error and are happy to correct it.  相似文献   
26.
Replicative senescence may be an important tumor suppressive mechanism for human cells. We investigated the mechanism of cell cycle arrest at senescence in human mammary epithelial cells (HMECs) that have undergone a period of 'self-selection', and as a consequence exhibit diminished p16INK4A levels. As HMECs approached senescence, the proportion of cells with a 2N DNA content increased and that in S phase decreased progressively. Cyclin D1-cdk4, cyclin E-cdk2 and cyclin A-cdk2 activities were not abruptly inhibited, but rather diminished steadily with increasing population age. In contrast to observations in fibroblast, p21Cip1 was not increased at senescence in HMECs. There was no increase in p27Kip1 levels nor in KIP association with targets cdks. While p15INK4B and its binding to both cdk4 and cdk6 increased with increasing passage, some cyclin D1-bound cdk4 and cdk6 persisted in senescent cells, whose inhibition could not be attributed to p15INK4B. The inhibition of cyclin E-cdk2 in senescent HMECs was accompanied by increased inhibitory phosphorylation of cdk2, in association with a progressive loss of Cdc25A. Recombinant Cdc25A strongly reactivated cyclin E-cdk2 from senescent HMECs suggesting that reduction of Cdc25A contributes to cyclin E-cdk2 inhibition and G1 arrest at senescence. Although ectopic expression of Cdc25A failed to extend the lifespan of HMECs, the exogenous Cdc25A appeared to lack activity in these cells, since it neither shortened the G1-to-S phase interval nor activated cyclin E-cdk2. In contrast, in the breast cancer-derived MCF-7 line, Cdc25A overexpression increased both cyclin E-cdk2 activity and the S phase fraction. Thus, mechanisms leading to HMEC immortalization may involve not only the re-induction of Cdc25A expression, but also activation of this phosphatase.  相似文献   
27.
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   
28.
Two recent studies published in this Journal draw attention to deficiencies in treatment of children with acute infectious diarrhoea in Australia.1,2 There is now no doubt that use of correctly constituted oral rehydration solutions provides optimal therapy for affected children unless circulation is compromised, vomiting is more than average, or complicating disorders are present. In the vast majority of cases, these complications do not occur. A high proportion of the childhood population experiences gastroenteritis at some time. It is known that 50% of Melbourne children require medical attention for rotavirus infection alone during their first 3 years of life, although less than 5% require admission.  相似文献   
29.
Computed tomography of the pancreas   总被引:2,自引:0,他引:2  
  相似文献   
30.
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