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1.
We investigated whether the src-family tyrosine kinase Lyn is involved in the generation of interferon alpha (IFN alpha) signals in haemopoietic cells. In vitro kinase assays using IFN alpha-sensitive cells of B-cell origin demonstrated the presence of IFN alpha-dependent kinase activity in anti-Lyn immunoprecipitates. Further studies demonstrated that Lyn associates via its src homology 2 (SH2) domain with the Janus family tyrosine kinase Tyk-2. This interaction was IFN alpha-dependent and involved direct binding of the SH2 domain of Lyn to the IFN alpha-activated form of Tyk-2. Thus, during binding of IFN alpha to its receptor in malignant haemopoietic cells, Lyn is engaged in an IFN alpha-signalling pathway, probably downstream of Tyk-2.  相似文献   

2.
JA McGregor  JI French 《Canadian Metallurgical Quarterly》1998,339(25):1858-9; author reply 1860
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3.
CONTEXT: Canada and the United States have reported a recent increase in the incidence of preterm birth, but the reasons for this increase are unknown. OBJECTIVE: To assess secular trends in preterm birth and its potential determinants. DESIGN: Hospital-based cohort study. SETTING: Canadian tertiary care university teaching hospital, 1978-1996. PARTICIPANTS: A total of 65574 nonreferred live births and stillbirths. MAIN OUTCOME MEASURES: Changes in occurrence of preterm birth, before and after adjustment for changes in method of gestational age assessment, obstetric intervention, registration of births weighing less than 500 g, and sociodemographic, behavioral, and clinical determinants. RESULTS: A crude secular increase in preterm births was seen for births less than 37, 34, and 32 completed weeks using 3 alternative gestational age estimation methods. Based on an algorithm incorporating both menstrual and early ultrasound gestational age estimates, rates increased from 6.6% to 9.8% for births at less than 37 weeks' gestation, 1.7% to 2.3% at less than 34 weeks, and 1.0% to 1.2% at less than 32 weeks. Exclusion of births weighing less than 500 g and those with induction or preterm cesarean delivery without labor before each of the corresponding gestational age cutoffs eliminated the secular trends for births before 34 and 32 weeks and attenuated the trend for births before 37 weeks. Nearly half of the remaining trend for births before 37 weeks was accounted for by the increasing use of early ultrasound dating. The residual trend was eliminated after controlling for secular increases in unmarried status and the proportion of women aged 35 years or older. These factors, combined with a decrease in alcohol consumption and increases in histological chorioamnionitis and cocaine use, appear to have counteracted a reduction in preterm birth since the mid-1980s that otherwise would have been observed. CONCLUSIONS: This hospital's increase in preterm births since 1978 parallels increases reported in population-based national studies from the United States and Canada. This trend appears largely attributable to the increasing use of early ultrasound dating, preterm induction and preterm cesarean delivery without labor, and changes in sociodemographic and behavioral factors.  相似文献   

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5.
The authors conducted a cohort study of low income women to determine the effect of physical activity on the risk of preterm birth. Women were sampled prenatally from four clinic sites and were scheduled for delivery at the University of Maryland Medical Systems (UMMS). Women who delivered infants at UMMS but who had received no prenatal care were also eligible. Preterm delivery was defined as a delivery prior to 37 completed weeks gestation. After adjusting for confounders, the odds of preterm delivery were increased for women who climbed stairs > or = 10 times per day (odds ratio (OR) = 1.60, 95% confidence interval 1.05-2.46) and for women who engaged in purposive walking > or = 4 days per week (OR = 2.10, 95% CI 1.38-3.20). Leisure-time exercise (> or = 60 days in the first and second trimesters combined) had a protective effect on preterm delivery (OR = 0.51, 95% CI 0.27-0.95). Television viewing had a U-shaped relation with preterm delivery (ORs (95% CI): < 15 hours, 2.09 (1.21-3.61); 29-42 hours, 1.50 (0.84-2.67); > 42 hours, 3.05 (1.75-5.40)). While the results support current recommendations regarding leisure-time activities, activities of daily living appear to increase risk of preterm delivery among low income women. These findings and those for television watching warrant further investigation.  相似文献   

6.
Telephonic nursing is an innovative approach to providing prevention-focused care to patients at risk for preterm birth. Telephonic nursing includes case management and direct care services. A focus on health promotion supports client empowerment in self-care and decision making during the high-risk pregnancy.  相似文献   

7.
Our study was designed to evaluate the pharmacokinetics, tissue distribution, toxicity and therapeutic efficacy of liposome-encapsulated paclitaxel (LET) in comparison to conventional paclitaxel. In normal mice, LET was much less toxic than the conventional drug. A dose of 32.5 mg/kg of conventional paclitaxel administered i.v. on three consecutive days produced 100% mortality by day three, while liposomal paclitaxel exhibited no mortality. The control group which received Diluent 12 (Chremophor EL and ethanol; 1:1 v/v), a vehicle used in conventional paclitaxel, 30% mortality was observed at this dosage level. In murine ascitic L1210 leukemia model, liposomal paclitaxel and conventional paclitaxel showed comparable antitumor activity. The pharmacokinetics of conventional paclitaxel and LET was studied in mice at dose levels of 5 mg/kg and 20 mg/kg. After intravenous administration of conventional paclitaxel at a dose of 5 mg/kg, the area under the plasma-concentration-time curve (AUC) was 2-fold lower and, the elimination half-life was 2-times shorter compared to LET. At a dose of 20 mg/kg, the terminal half-lives were comparable, however, conventional paclitaxel displayed non-linear pharmacokinetics with disproportionate increase in AUC. At the two dose levels studied, LET demonstrated linear kinetics. Tissue distribution of paclitaxel after administration of LET showed levels 10-fold higher in spleen and 3.5-fold higher in liver as compared to conventional paclitaxel. The significant decrease in toxicity shown by LET, coupled with an increase in plasma AUC and half-life indicates that LET may be a viable alternative to the therapeutic use of the conventional preparation of paclitaxel.  相似文献   

8.
Eighteen cases of spastic diplegia (SD) ranging in age from 5 year 4 month to 9 year 5 month with preterm birth were studied to clarify the relationship between visuo-perceptual impairment and their cerebral lesions. All underwent neuropsychological examinations including the Frostig developmental test of visual perception, Tanaka-Binet or Suzuki-Binet intelligence test, and MRI examination. Cerebral lesions were detected in all subjects, and the volume of the peritrigonal white matter of the parietal and occipital lobes was significantly correlated with the visuo-perceptual impairment (r = 0.74, in the axial plane; r = 0.64, in the coronal plane). We propose that visuo-perceptual impairment is caused by cerebral lesions and that the measurement of peritrigonal white matter by MRI is useful for detecting potential visuo-perceptual impairment at an early age.  相似文献   

9.
Inclusion body myositis is an increasingly recognised form of inflammatory myopathy with characteristic clinical and histopathological features which has seldom been reported in the United Kingdom. This paper presents the clinicopathological features of a series of patients diagnosed in Nottingham from 1986 to 1990. During this period, 1319 muscle biopsy samples were processed by this laboratory and rimmed vacuoles were seen in 17 patients. Eleven patients had definite or probable inclusion body myositis according to published criteria. The mean age of the group was 69.4 years with a male to female ratio of 8:3. Typical clinical features were a slowly progressive painless, proximal lower limb weakness, with muscle wasting and early loss of reflexes. The median duration of illness from first symptom to presentation was five years (range 2-18 years). Falls were a prominent symptom in six patients and distal weakness occurred in nine patients. Creatine kinase was increased in 10 patients but only one had a level > 1000 IU/l; the erythrocyte sedimentation rate was normal in five patients. Treatment with steroids or cytotoxic drugs, or both, did not prevent disease progression. It is confirmed that inclusion body myositis is a distinct cause of inflammatory myopathy which is probably underdiagnosed in the United Kingdom. Clinically, it should be suspected in older patients presenting with muscle weakness of insidious onset. Pathologically, a careful search should be made for rimmed vacuoles and inflammation; ultrastructurally, the presence of inclusions will confirm the diagnosis.  相似文献   

10.
Objective: To determine whether the pattern of prenatal stress, as compared to prenatal stress assessed at a single gestational time point, predicts preterm delivery (PTD). Design: Perceived stress and anxiety were assessed in 415 pregnant women at 18-20 and 30-32 weeks' gestation. Main Outcome Measures: Gestational length was determined by last menstrual period and confirmed by early pregnancy ultrasound. Births were categorized as preterm (  相似文献   

11.
This registry-based cohort study aimed to describe the relationship between pregnancy complications in the first and second pregnancy, focussing on idiopathic and indicated preterm birth of singleton infants in either pregnancy. The cohort consisted of all women living in Denmark with a first singleton birth in 1982 and a second in the period 1982-1987 (13,967 women). The risk of a second preterm birth was not significantly different between women who had an idiopathic or an indicated first preterm birth (15.2 and 12.8% respectively). Adjustment by logistic regression analysis for other risk factors for preterm birth did not influence the relative risk (6.0 before 32 weeks and 4.8 between 32 and 36 weeks) of a second preterm birth subsequent to a first one. Women with idiopathic preterm delivery in their first or second pregnancies give birth to infants with lower birth weight in previous or subsequent pregnancies. Emergency cesarean section in a first term pregnancy was a risk factor for subsequent idiopathic preterm birth.  相似文献   

12.
OBJECTIVE: The Prechtl method of qualitative assessment of general movements (GMs) has been shown to be a good predictor of neurologic outcome in fetuses, preterm infants, and term infants. The aim of this study was to compare the results of this new technique with those of traditional neurologic examination and of cranial ultrasonography in preterm infants. METHODS: Serial videotape recordings (with off-line assessment of GMs), ultrasound examination of the brain, and neurologic examinations were performed from birth until about 6 months of corrected age, on a group of 66 preterm infants whose gestational age ranged from 26 to 36 weeks (mean 30.7 weeks). The agreement between the two techniques and their predictive power, with respect to the neurologic outcome at 2 years of corrected age, were evaluated for five different age groups from preterm age to 65 weeks of postmenstrual age. RESULTS: Overall agreement of the neurologic and GM findings was 80.3% and strongly age related (lower during the preterm and term periods and higher thereafter). At all ages the results of GM observation correlated highly with neurologic outcome; they showed higher sensitivity and specificity than the neurologic examination. This held true in particular before term age, when poor neurologic responses might be related to transient complications, and at term age, mainly because of infants with normal neurologic examination results but unfavorable outcome. During the preterm period the ultrasound results showed a better specificity and a lower sensitivity to outcome than GM findings. CONCLUSIONS: The results of this study indicate that quality assessment of GMs should be added to traditional neurologic assessment, neuroimaging, and other tests of preterm infants for diagnostic and prognostic purposes.  相似文献   

13.
This paper addresses two questions: 1) What is the relation of hemoglobin in the second gestational month to preterm birth and low birth weight? 2) How does the relation differ when hemoglobin in the fifth or eighth month or the lowest pregnancy hemoglobin are examined in place of first trimester values? These relations were examined prospectively in 829 women from Shanghai, China in 1991-1992. The population was nearly homogeneous by race, parity, antenatal care, and smoking. Rates of birth outcomes were compared between hemoglobin categories based on 10 g/liter groupings, with 110-119 g/liter as the reference group. Rates of low birth weight and preterm birth (but not small-for-gestational age) were related to early pregnancy hemoglobin concentration in a U-shaped manner. The relative risks (95% confidence intervals) for preterm birth in women by g/liter of hemoglobin were 2.52 (0.95-6.64) for > or = 130 g/liter, 1.11 (0.41-2.99) for 120-129 g/liter, 1.64 (0.77-3.47) for 100-109 g/liter, 2.63 (1.17-5.90) for 90-99 g/liter, and 3.73 (1.36-10.23) for 60-89 g/liter. Use of hemoglobin values in the fifth or eighth month attenuated the association with preterm birth. When lowest pregnancy hemoglobin values were used, the association of anemia with both outcomes was obscured, and risk of preterm birth at high hemoglobin values increased dramatically.  相似文献   

14.
BACKGROUND: Fifteen years after the implementation of an antenatal risk screening program in Cape Verde, the first assessment of an association between maternal obstetric characteristics and preterm birth or low birthweight (LBW) infants was undertaken. METHODS: A cohort of 353 systematically selected antenatal clinic attenders in the county of Praia, Cape Verde, was studied prospectively during the period October 1991 through December 1992. The cohort was followed past the perinatal period and information was obtained according to a pretested structured questionnaire. In the analysis of preterm birth and LBW, multiple logistic regression was listed to estimate the relative risks of ll background variables. RESULTS: The prevalence of preterm birth (<37 gestational weeks) was 12%, and the prevalence of LBW infants was 8%. Low birthweight (<2500 grams) was significantly associated with low maternal age (< or = 19 years, RR=3.7); nulliparity (RR=5.2) and obstetric history of previous LBW infant (RR-6.5). The risk of preterm birth was significantly increased if the woman had an obstetric history of hypertension or convulsions (RR=2.6). CONCLUSIONS: In the setting studied, teenage women and women with previous pregnancy hypertension should be given selective attention in antenatal care to achieve improved pregnancy outcome. Primary prevention is needed to lower the prevalence of teenage pregnancies.  相似文献   

15.
AIM: To observe changes in body composition during the first week after birth, in preterm neonates with and without respiratory distress syndrome (RDS), so as to be able to provide optimal fluid and energy intake. METHODS: Twenty four babies with RDS and 19 healthy preterm babies, with gestational ages ranging from 26-36 weeks, were studied daily for the first week after birth. Total body water (TBW) was measured using bioelectrical impedance analysis. The babies were weighed daily and a record made of fluid and energy intake. Body solids were calculated as the difference between body weight and TBW. RESULTS: There was a highly significant reduction in body weight by the end of the week, with the RDS babies losing more than the healthy babies (RDS 7.6%; non-RDS 3.7%). There was no significant difference in the amount of TBW at birth in the babies with and without RDS (RDS 85.1%; non-RDS 85.5%) and both groups lost the same amount of body water (RDS 10.9%; non-RDS 9.9%) by the end of the first week. The amount of total body water lost was unrelated to the volume of fluid administered. There was a loss of body solids during the first day in the RDS group, but, overall, there was a highly significant increase in both groups between birth and day 7, which was greater in the healthy babies (RDS 13.0%; non-RDS 42.7%). CONCLUSIONS: Loss of body water after birth occurs to the same extent in healthy preterm neonates and in babies with RDS and is unrelated to the volume of fluid administered. Given adequate nutritional support, an increase in body solids can accompany early postnatal weight loss and begins almost immediately after birth, in both healthy preterm babies and babies with RDS.  相似文献   

16.
17.
The safety of estrogen use in breast cancer patients is discussed. Most reports indicate there is no risk.  相似文献   

18.
Decreased neutrophil chemotaxis has been implicated in the pathophysiology of the disease, localized juvenile periodontitis (LJP). The biological basis for the altered neutrophil function in LJP has been suggested to be an intrinsic cellular defect, involving a decrease in the number of N-formyl-methionyl-leucyl-phenylalanine (FMLP) receptors on the cell surface. We have investigated the relative contribution of serum-borne factors in the modulation of neutrophil functions in LJP, in a large population of LJP patients and healthy control subjects (HS). Treatment of HS-neutrophils with LJP-sera, resulted in a decreased neutrophil chemotactic response, and down regulation of FMLP receptors on the cell surface. Pretreatment of LJP-sera with anti-TNF and anti-IL-1 antibodies effectively, although incompletely, neutralized the ability of LJP-sera to modulate chemotaxis and FMLP receptor levels in HS-neutrophils. The changes induced by LJP sera were specific and sustained and could not be reversed by placing LJP-serum treated neutrophils in HS-serum. Sera obtained from HS and patients with adult periodontitis (AP), both of which exhibit normal chemotaxis, and patients with clinically diagnosed LJP with normal neutrophil chemotaxis (LJP-nctx) did not modulate HS neutrophil chemotaxis or FMLP receptors. Furthermore, recombinant human TNF-alpha, rhIL-1 alpha and rhIL-1 beta, at very low concentrations (15 pg/ml to 150 pg/ml), modulated the chemotactic response as well as FMLP receptor numbers on HS-neutrophils, in a manner similar to those observed in LJP. The present findings demonstrate that the biologic basis for the altered neutrophil function may not be an intrinsic cellular defect in neutrophils, but at least in part due to quantitatively small but biologically significant elevations in the levels of TNF-alpha and IL-1 in the serum.  相似文献   

19.
Delayed hemolytic transfusion reaction occurred in a 74-year-old woman after coronary bypass. Antibodies were not detected during preoperative screening but did appear late after exposure to Jkb-positive red blood cells, probably as an anamnestic response to previous exposure during childbirth or remote transfusion. The incidence, pathophysiology, clinical presentation, diagnosis, and management of this syndrome are discussed.  相似文献   

20.
Predictors of maternal depression trajectories were examined longitudinally in families with an infant born preterm or at a low birth weight. A total of 181 mother–infant dyads enrolled in the study before the infant’s neonatal intensive care unit (NICU) discharge. Maternal depressive symptoms were assessed at 5 timepoints, and contextual variables and infant risks were assessed at NICU discharge. Hierarchical linear models revealed that mothers who experienced more risk factors reported more depressive symptoms just before their infant’s NICU discharge and showed less decline in depressive symptoms in the months immediately following the child’s birth. Although cumulative risks predicted depression trajectories, this effect appeared driven by maternal and family sociodemographic risks rather than infant risks. Addition of family support as a covariate in the multilevel models with a subsample of families revealed that social support and depression covaried across time. However, most of the findings regarding the association between risk and depression remained consistent, whereas the effects of maternal race and multiple birth were slightly attenuated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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