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981.
Sublethal doses (0.00, 0.25, 0.50 and 1.00 mg/kg b.w./day) of vomitoxin (deoxynivalenol; DON) were studied for their effects on humoral and cellular immunity and serum proteins of inbred, male Swiss Webster mice in a series of 4 separate experiments. Vomitoxin was added to basal diet (less than the detection limit, i.e., less than 0.05 micrograms of vomitoxin per g of feed) and administered to mice for 5 weeks beginning at 21 days of age. Mice in experiment 2 were fed the basal diet for 40 days in addition to the 5-week treatment with vomitoxin. The 1.00 mg/kg dose of vomitoxin resulted in a statistically significant reduction in the serum levels of alpha 1 and alpha 2-globulins, an increase in total serum albumin, and a reduction in feed consumption and body weight gain compared to the control group. The 0.50 mg/kg dose of vomitoxin resulted in significantly reduced serum levels of alpha 2- and beta-globulins while a significant reduction of feed consumption was evident only during Week 4. Similarly, body weight gain in this group of mice was significantly reduced during Week 2 but increased to normal levels during Week 3 and remained parallel to the control for Week 4 and 5. Both levels (0.50 and 1.00 mg/kg) of vomitoxin resulted in a reduced, dose-related, time-to-death interval following a challenge with L. monocytogenes and increased proliferative capacity of splenic lymphocyte cultures stimulated with the phytohemagglutinin P (PHA-P) mitogen compared to the control group of mice. The 0.25 mg/kg dose of vomitoxin did not have any significant effects on the parameters studied. A reasonable estimation of a 'no effect' level for immunologic effects in mice based on these and previous immunological studies would seem to be between 0.25 and 0.50 mg/kg b.w./day.  相似文献   
982.
Wheat germ agglutinin (WGA) was found to stimulate DNA synthesis in human peripheral blood mononuclear cells at relatively low concentrations and to inhibit DNA synthesis at higher concentrations. Both actions were inhibited by oligomers of N-acetyl-D-glucosamine. Significant mitogenic activity was dependent on the use of human (as opposed to fetal calf) serum to supplement the culture medium. Purified T cells responded to WGA very weakly and the incorporation of thymidine into non-T cells in response to WGA was less than the lectin-free control. The full ability of T cells to respond to WGA was restored by the addition of monocytes, but not by any other blood cells. Interleukin 2 partially restored the ability of T cells to respond to WGA; interleukin 1 was less effective. WGA displayed a strong synergistic action with the tumour promoter, 12-O-tetradecanoyl-13-acetate (TPA), in stimulating DNA synthesis in separated T (but not non-T) cell fractions, and in unfractioned mononuclear cells. These results reconcile most of the conflicting reports in the literature concerning the interaction of WGA with human lymphocytes.  相似文献   
983.
A cohort of 1163 pregnant women in two small towns in South Wales, UK, was identified and followed until the children born to them were five years of age. Growth in these children is described and a number of determinants identified. Social-class differences were very small at birth but differences in height became clear by the age of two years and in head circumference before this. In height the differences were largely accounted for by greater growth in social class I, but there was a gradient in head circumference throughout all the social classes. The social class effects gradually increased as the children became older. Parity of the mothers had a small effect on size at birth but age of the mother had no effect once parity was allowed for. Data on illnesses in the children were collected but no effect on growth could be detected. By far the most important determinant of growth which could be controlled is maternal smoking. About 40% of the women smoked, about 17% heavily (15 or more cigarettes per day) and the prevalence of smoking altered little during pregnancy. There was a graded effect of smoking on growth up to a 9% deficit in birth-weight, a 2% deficit in length at birth and a 1.5% deficit in head circumference in the babies born to the mothers who smoked most heavily (25 or more cigarettes per day) compared with non-smokers. There effects decreased with age but there were still residual effects at age five years.  相似文献   
984.
The notion that the intrauterine contraceptive device (IUCD) has a central, as well as a local action, is examined. Although the IUCD undoubtedly has a local action, certain IUCD related side effects, e.g. galactorrhoea, bloating and premenstrual syndrome and inadequate luteal function can be explained if the IUCD has some central action. The powerful postcoital anti-fertility effect of both copper-bearing and plain plastic IUCDs probably also depends to some extent on a central action. The central action of the IUCD is probably due to initiation of reflex hypothalamic activity following intrauterine reflex stimulation. The hypothalamic response to IUCD insertion consists of release of beta-endorphin accompanied by raised levels of prolactin, vasopressin and oxytocin.  相似文献   
985.
The Brief Symptom Inventory (BSI), a 53-item psychiatric symptom checklist, was administered to 57 alcoholic inpatients on days 2, 10, 18 and 26 of their 28-day stay in an alcoholism rehabilitation unit at a Veterans Administration hospital. The results of the test show a steady decline in the patients' psychiatric symptomatology from week 1 to week 4 with the most dramatic improvement evidenced between weeks 1 and 2.  相似文献   
986.
Existing methods for estimating additional days of hospital stay due to nosocomial infections (NI) have a number of documented limitations. An alternative method described in this paper uses the Appropriateness Evaluation Protocol (AEP) to determine whether each day of acute inpatient care is appropriate based on the need for care of the NI, original cause of hospitalization (OC), or combined NI-OC requirements. Using this method to identify specific days of hospitalization due to Staphylococcus aureus nosocomial infection, we find: 1) length of stay is increased for only a minority of patients (38%); 2) an average of 20 additional days of stay occurred for patients with 1 or more days attributed to NI; and 3) an average of 52% of length of stay of patients with 1 or more days attributed to NI can be attributed to the NI. Application of the AEP-based method is a useful alternative for identifying additional days of stay due to NI.  相似文献   
987.
Pregnancy-induced hypertension (PIH) can be complicated by maternal or fetal thrombocytopenia, or both. In order to investigate possible immunologic causes of these thrombocytopenias, platelet-associated IgG (PAIgG) and IgM (PAIgM) were measured in mothers with PIH and in their infants and compared with those from patients with autoimmune thrombocytopenic purpura (ATP), a known immunodestructive platelet disorder. Many PIH patients (33.3%) and most ATP patients (68.1%) had elevated levels of maternal PAIgG. In both diseases, the amount of PAIgG was directly proportional with the degree of thrombocytopenia (r = 0.446 in PIH and R = 0.668 for ATP). But in neither disease did the degree of maternal thrombocytopenia correlate with the degree of neonatal thrombocytopenia (r = 0.153 for PIH and R = 0.175 for ATP). Umbilical cord samples from PIH patients contained PAIgG (53.3%) and PAIgM (53.8%), whereas the umbilical cord samples from ATP patients had elevated amounts of PAIgG but not PAIgM. PAIgM in the umbilical cord blood could not be accounted for by IgM rheumatoid factors, IgM-containing immune complexes, or non-specific adsorption because of elevated total IgM levels. The umbilical cord blood PAIgM was probably not of maternal origin because it was observed even when the maternal blood contained no PAIgM and maternal IgM is not normally transported transplacentally. Therefore, the PAIgM appears to be of fetal origin. These results suggest that both maternal and fetal immunologic mechanisms may be involved in PIH-induced thrombocytopenia; if so, this is one of the first reported examples of a possible fetal autoimmune response.  相似文献   
988.
Residual pancreatic B-cell function was investigated in children with diabetes mellitus in whom classification of the type of disease was difficult at the first visit. Intravenous glucagon tests were performed at the first visit and subsequently, the C-peptide responses compared. Based on our data on a limited number of patients, we propose C-peptide concentrations of 3.0 to 3.5 ng/ml at the peak or at 6 min after injection of glucagon, as the critical level which distinguishes non-insulin dependent from insulin-dependent diabetes mellitus. However, the degree of obesity, clinical stage and other factors also need to be considered in the classification of diabetes mellitus.  相似文献   
989.
Adolescent stress is an emerging area of importance in considerations of the health of young people. Exposure to stress predicts a range of both physical and mental health problems in adolescents and relates, as well, to the initiation of important health risk behaviours. Yet the measurement of stress in adolescents has been as fraught with methodological difficulty as it has been for adults. This paper examines the Adolescent Stress Questionnaire (ASQ) which was developed specifically to address the domain of stressors specific to adolescent experience and looks at three cohorts of responses to this questionnaire over time (1995, 1998 and 2001). It assesses the stability of the original 7‐factor structure of the ASQ over time, and while confirmatory factor analysis indicates that stability to be acceptable, it also suggests that either adolescent stressors themselves, or the language by which they are reported, vary sufficiently over time to warrant the refinement of the instrument. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
990.
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