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621.
In urea kinetic modeling, postdialysis blood urea nitrogen (BUN) is usually underestimated with an overestimation of the Kt/V especially in high-efficiency hemodialysis (HD). Thus, an artificial neural network (ANN) was used to predict the equilibrated BUN (Ceq) and equilibrated Kt/V (eKt/V60) by using both predialysis, postdialysis, and low-flow postdialysis BUN. The results were compared to a Smye formula to predict Ceq and a Daugirdas' formula (eKt/V30) to predict eKt/V60. Seventy-four patients on high-efficiency or high-flux HD were recruited. Their mean urea rebound was 28.6+/-2%. Patients were divided into a "training" set (n = 40) and a validation set (n = 34) for the ANN. Their status was exchanged later, and the two results were pooled. In the prediction of Ceq, both Smye formula and low-flow ANN were equally highly accurate. In patients with a high urea rebound (>30%), although Smye formula lost its accuracy, low-flow ANN remained accurate. In the prediction of eKt/V60, both Daugirdas' formula and low-flow ANN were equally accurate, although the Smye formula was not so accurate. In patients with a high urea rebound, although both Smye and Daugirdas' formulas lost their accuracy, low-flow ANN remained accurate. We concluded that low-flow ANN can accurately predict both Ceq and eKt/V60 regardless of the degree of urea rebound. 相似文献
622.
LM Irgens T Markestad V Baste P Schreuder R Skjaerven N Oyen 《Archives of disease in childhood》1995,72(6):478-482
OBJECTIVE--To investigate, in a population based national study, the association between sleeping position of infants and the occurrence of sudden infant death syndrome (SIDS). DESIGN--A retrospective survey and registry based ecological study. A questionnaire based surveillance of sleeping position was obtained in a random sample (n = 34,799) and surveillance of SIDS was based on all infants born in Norway 1967-91, surviving the perinatal period. Variables studied from the questionnaire were usual sleeping position (placed), breast feeding at 3 months, and maternal smoking in pregnancy, and from the Medical Birth Registry maternal age, birth order, and birth weight. RESULTS--Proportion of infants sleeping prone increased from 1970 (7.4%) to 1989 (49.1%) and dropped in 1990 (26.8%) and 1991 (28.3%). Occurrence of SIDS increased from 1970 (1.1/1000) to 1989 (2.0) before dropping in 1990 and 1991 (1.1). IMPLICATION AND RELEVANCE OF RESULTS--A cause effect relationship between prone sleeping and SIDS as suggested in previous studies is supported by the present; and so far only, national study of infants' sleeping position. 相似文献
623.
Mutational activation of the K-ras oncogene often occurs in human and mouse
lung adenocarcinomas. Since K-ras p21 functions in trans-membrane
signaling, we have investigated whether the amount of this protein in lung
cell membranes is a variable that could influence lung tumorigenesis,
either due to genetic differences or in response to tumor promoters. The
six mouse strains assessed showed little difference in the total lung K-ras
p21 after immunoprecipitation and immunoblotting. However, amount of ras
p21 in the membrane fraction showed significant differences, with C57BL/6
and BALB/c having 3-5-fold more than NIH Swiss, AKR and DBA mice.
Interestingly, a congenic AKR strain having the Ahr(b-1) Ah receptor allele
from C57BL/6 mice (designated AKR.B6Ah) had high lung membrane K-ras p21
similar to that of C57BL/6. To test for possible changes related to lung
tumor promotion, mice were treated with a promotional dose of TCDD (5
nmol/kg). After 48 h C57BL/6 lungs showed an increase in p21 in both total
and membrane fractions. BALB/c, DBA and Swiss mice showed an increase only
in membranes. There was no change in the AKR and AKR.B6Ah. Aroclor 1254
(250 mg/kg) caused an increase in membrane/cytosol ratio in Swiss mice.
Thus the membrane:cytosol K-ras p21 ratio may be influenced by the Ahr
phenotype, and TCDD and PCBs can induce p21 or increase its membrane level
in certain strains, but these properties are not fully dependent on Ahr
receptor type. In confirmation of the relevance of these findings for the
tumor target cell type, the immortalized alveolar type 2 E10 cell line
presented K- ras p21 in membrane, and this was increased 4-fold by
treatment with 10 nM TCDD.
相似文献
624.
B Alm J Milerad G Wennergren R Skjaerven N Oyen G Norvenius AK Daltveit K Helweg-Larsen T Markestad LM Irgens 《Archives of disease in childhood》1998,78(4):329-334
AIM: To establish whether smoking is an independent risk factor for sudden infant death syndrome (SIDS), if the effect is mainly due to prenatal or postnatal smoking, and the effect of smoking cessation. METHODS: The analyses were based on data from the Nordic epidemiological SIDS study, a case-control study with 244 cases and 869 controls. Odds ratios were computed by conditional logistic regression analysis. RESULTS: Smoking emerged as an independent risk factor for SIDS, and the effect was mainly mediated through maternal smoking in pregnancy (crude odds ratio 4.0 (95% confidence interval 2.9 to 5.6)). Maternal smoking showed a marked dose-response relation. There was no effect of paternal smoking if the mother did not smoke. Stopping or even reducing smoking was beneficial. SIDS cases exposed to tobacco smoke were breast fed for a shorter time than non-exposed cases, and feeding difficulties were also more common. CONCLUSIONS: Smoking is an independent risk factor for SIDS and is mainly mediated through maternal smoking during pregnancy. Stopping smoking or smoking less may be beneficial in reducing the risk of SIDS. 相似文献
625.
A total of 121 infants entered a cohort serological study of primary infections with herpes-viruses. All of them had seven samples of blood available: the first sample was taken soon after birth, the other six were taken at 1, 2, 3, 6, 12, and 14 months of age. One sample of maternal blood was collected immediately after delivery. All blood samples were tested for antibodies against cytomegalovirus, Epstein-Barr virus, and human herpesvirus-6 (HHV-6). Primary cytomegalovirus infection occurred early; the cumulative infection rates were 1.7%, 8.3%, 18.3%, 25%, 52.5%, and 65% by the ages of 1, 2, 3, 6, 12, and 14 months, respectively. Epstein-Barr virus infection was not seen before 3 months of age and slowly emerged thereafter, reaching a cumulative rate of 1.7%, 11.6%, 21.5% at the ages of 6, 12, and 14 months, respectively. Primary HHV-6 infection was also a rare event in the first three months of life, but peaked between 6 and 12 months of age. No detectable risk factors were associated with primary Epstein-Barr virus or HHV-6 infection. The risk factors associated with cytomegalovirus infection included breast feeding, fewer children in household, and care by a babysitter. 相似文献
626.
B Espehaug AK Daltveit SE Vollset N Oyen A Ericson LM Irgens 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(9):977-982
In recent years, considerable attention has been attached to the disquieting fact that infant survival is much lower in Norway than in Sweden. In the present study, comprising all live single births in Norway and Sweden during 1985–88, the observed infant mortality was 1.5 times higher in Norway than in Sweden. The largest difference between Norway and Sweden was found in infants of young mothers with high birth order. Thus for the second births of mothers aged less than 20 years the observed mortality ratio of Norway to Sweden was 1.8. The infant mortality ratio decreased with increasing maternal age for all birth orders, and for the second births of mothers aged 35 years or more the mortality ratio was 1.0. The higher infant mortality in Norway was evident throughout the first year of life, with the highest mortality ratio observed at 6–8 months of life. Adjustment for maternal age, birth order and geographical region did not alter the observed infant mortality ratios. In both countries, the highest risk was found among infants of young mothers, This suggests a need for a more extensive preventive health care system directed at young mothers during their pregnancy and the infancy period. 相似文献
627.
自身免疫性肝炎患者自身抗体的测定及意义 总被引:3,自引:1,他引:2
目的:探讨自身抗体测定对诊断自身免疫性肝炎的临床意义.方法:采用间接免疫荧光法(IIF)检测47例自身免疫性肝炎患者、158例非自身免疫性肝炎患者及40例健康体检者体内抗核抗体(ANA)、抗平滑肌抗体(SMA)、抗中性粒细胞胞质抗体(ANCA)、抗线粒体抗体(AMA)等自身抗体,ELISA法检测抗MPO抗体,并对结果进行回顾性分析.结果:ANA、SMA及ANCA检出率的比较,结果显示AIH中阳性率最高为SMA(66.0%, 31/47),而非AIH中则为6.3%(10/158),两组差异有非常显著性意义(P<0.01).经X2检验, SMA、AMA和MPO抗体检测在AIH与PBC中,均有非常显著性意义(P<0.01).AIH各型自身抗体检测结果表明,AIH-Ⅰ与ANA、SMA和ANCA相关,AIH-Ⅱ与LKM相关,而AIH=Ⅲ与SLA和ANCA相关.结论:血清自身抗体的检测对诊断、治疗和阻止自身免疫性肝炎的发展有着十分重要作用,对提高AIH在临床上同其他肝病鉴别诊断和治疗有着非常重要的意义. 相似文献
628.
Introduction : The purpose of this study was to explore college students' beliefs about childbirth and midwifery. Methods : A critical qualitative analysis was used to identify common themes that occurred in an online class discussion about midwifery. Results : This population of 459 college students drew on the larger social discourse of the medical model of childbirth to frame their discussion of childbirth and midwives. Common beliefs that emerged from class discussions included the perceived dangerous nature of childbirth, the necessity for technologic interventions in childbirth, and doubts about the quality of midwifery training and practice. Discussion : To promote midwifery among this population, advocates should continue public education efforts through a variety of media and communication strategies, with an emphasis on the safety of midwifery care. J Midwifery Womens Health 2010;55:117–123 c̊ 2010 by the American College of Nurse‐Midwives. 相似文献
629.
630.
Caroline E Wyers José JL Breedveld-Peters Petronella LM Reijven Svenjhalmar van Helden Nick A Guldemond Johan L Severens Aart D Verburg Berry Meesters Lodewijk W van Rhijn Pieter C Dagnelie 《BMC public health》2010,10(1):212