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81.
Antibodies against some microorganisms, naturalhaemagglutinins, and organospecific autoantibodies were examined in bronchial secretions of 40 patients suffering from chronic obstructive bronchitis. The determinations were effected in sputa prepared for serological analysis by ultracentrifugation, ultrasonic treatment, and subsequent freeze drying. The lyophilized substance was redissolved in distilled water in a concentration of 100 mg/ml. The results were compared with the values obtained in the blood sera of the same patients. Antibodies were found in all the sputa examined. Against type A2 and B influenza virus, antistreptolysin-O and isoagglutinins anti-A and anti-B, and natural haemagglutinins against rabbit and rat erythrocytes. The anti-adenoviral antibodies were present in 41.4% of cases, the anti-lung autoantibodies in 52.8% of the sputa examined. A significant positive correlation was observed between the level of haemagglutinins of sputa and of the corresponding sera. This finding argues for the existence of a common regulatory system of the natural haemagglutinins belonging to the local and the general immune system. It was found a slight correlation or no correlation in the case of anti-influenza virus antibodies; this phenomenon is attributed to the local production of the antiviral antibodies under the direct influence of microorganisms as antigens. The positive correlation existing between the titers of some antibodies of bronchial secretions and the corresponding IgA levels and the fail of such a correlation with IgG concentrations show that the serological activity of the sputum is linked mainly to the secretory IgA. Among the sputum fractions separated by Sephadex G-200 gelfiltration, the most expressed serological activity was observed in the first fraction containing the highest amounts of IgA. After absorption of the samples with specific anti-IgG or with anti-IgG plus anti-IgM immunosera the antibody activity against influenza virus and against iso- and heterologous erythrocytes remained unchanged or decreased moderately, while the absorption with anti-IgA immunoserum removed completely or almost completely this activity. This finding shows that the antibodies of the sputum belong to the IgA class. The reduction with 2-mercaptoethanol affects moderatly the antibody capacity of the immunglobulins of the sputum. 相似文献
82.
Mary Ann Matteson Adrianne D. Linton Susan J. Barnes 《Journal of nursing scholarship》1996,28(3):233-240
Systematic observations of people suffering from dementia of the Alzheimer's type (DAT) reveal they regress in behavior and become childlike. These observations have been used to structure clinical research and therapeutic interventions for dementia patients. However, no concise framework explains successful caregiving. Models for care exist but they lack an adequate framework for the long-term care of a person with DAT. This state of the science review describes what is known about cognitive functioning in people with DAT. It examines studies based on cognitive functioning. It also then relates this information to an emerging theory tentatively identified as a "cognitive developmental approach" which may be useful for understanding people with dementia and for predicting caregiver requirements. 相似文献
83.
Female Sprague-Dawley rats fed purified diets containing 5% or 20% fat as beef tallow or rapeseed oil plus corn oil were given 2.5 mg 7,12-dimethylbenz(a)anthracene intragastrically at age 55 days. Mammary tumorigenesis was not significantly increased in rats fed diets high in beef tallow or rapeseed oil compared to rats fed 5% fat. In earlier studies in rats fed similar diets containing corn oil or lard, mammary tumorigenesis was enhanced by the high fat diets. These results indicate that dietary fats vary in their ability to increase mammary tumorigenesis in rats.In addition, body weight, feed efficiency ratios, sexual maturation, and estrous cycles were examined. High erucic acid rapeseed oil did not support growth as well as beef tallow, and feed efficiency ratios were decreased in animals fed the higher amount of the oil. There was no significant dietary fat effect on age at vaginal opening or regularity or duration of estrous cycles. 相似文献
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OBJECTIVE: To provide data on medical students' multivitamin and calcium supplement use during medical school. DESIGN: Medical students were anonymously surveyed at three time points: freshman orientation, orientation to wards, and during senior year. SUBJECTS: Medical students (n = 2,316) at 16 US medical schools (response rate = 80.3%). OUTCOME MEASURES: Prevalence and correlates of multivitamin and calcium supplement use throughout medical school. STATISTICAL ANALYSES: Chi2 tests with associated P values, and logistic regression with associated odds ratios and confidence intervals. RESULTS: Half of medical students surveyed used multivitamins, and 19% used calcium supplements, at least once per week as freshmen. Consumption of calcium, but not multivitamin, supplements increased during subsequent years (P = 0.0001) and both supplements were more commonly used by women (P < 0.0003). Of 970 students tracked across all three time points, 14% of women, compared with only 2% of men (P < 0.0001), took calcium at all three time points. Using multivariate models, we found that medical students were more likely to use multivitamins if they exercised regularly, had children, were underweight, or were women who were not heavy users of alcohol (P < 0.0001 to P < 0.05). Similarly, students who were women, underweight, exercised regularly, or had a personal or family history of osteoporosis were more likely to consume supplemental calcium (P < 0.0001 to P = 0.04). CONCLUSIONS: Medical students of all types used supplements at moderate rates, and women used supplements more commonly and consistently than did men. Medical students, especially nonunderweight and nonexercising students, may be particularly important targets for messages regarding appropriate and adequate vitamin/mineral use. 相似文献
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M Dietrich C Abt R Arnold H Pflieger D Hoelzer E Kurrle H Rasche B Kubanek H Heimpel T M Fliedner 《Onkologie》1979,2(3):102-107
60 adult patients with acute leukemia (AL) previously untreated or in relapse received induction chemotherapy with different types of supportive care. Group A was decontaminated by nonabsorbable antibiotics in strict reverse isolation, group B was isolated only and group C was treated under routine hospital conditions. There were less infections in group A and B compared with group C. 76% of patients in group A achieved remission, in contrast to 57% in group B and 59% in group C. Late evaluation three years after termination of the study showed that all patients were dead except four patients being in first remission after discontinuation of maintenance treatment. Three patients were treated in group A, one patient in group C. However, the differences of survival and remission rates were not significant. Failure to demonstrate significant advantage of isolation and decontamination in treatment of AL was caused by insufficient suppression of microbes by the applied antimicrobial measures. Thus, it is suggested to investigate better antimicrobial treatment before gnotobiotic care is accepted as routine supportive treatment in AL. 相似文献
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