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81.
It is known that in the blood of patients with some autoimmune diseases catalytically active antibodies hydrolyzing proteins, DNA, and RNA may be detected. In the present work homogeneous preparations of IgG antibodies (Ab) possessing high affinity for nucleic acids (NA) were obtained for the first time from blood and cerebrospinal fluid of patients with multiple sclerosis (MS). The fraction of IgG Ab as well as its Fab fragments and isolated light chains of both kappa- and lambda-types were shown to catalyze effectively the hydrolysis of DNA and RNA. It is shown by different methods that the capability for nucleic acid hydrolysis is an intrinsic property of the polyclonal Ab. NA-hydrolyzing Ab were detected in the blood of 69 of 72 and in the cerebrospinal fluid of 5 of 5 examined MS patients, while they were not detected in the blood of any of 50 healthy donors examined. Comparison of relative rates of RNA hydrolysis and of the substrate specificity in hydrolysis of various model RNAs--cCMP, poly(U), poly(A), and poly(C)--revealed pronounced differences of MS antibodies from ribonucleases of human blood, ribonuclease A, and all earlier described abzymes. The abzymes are usually characterized by relatively low specific activities in comparison with that of normal enzymes catalyzing analogous reactions. Ab from the blood of MS patients are the first example of autoabzymes whose specific activity in RNA hydrolysis is comparable or even higher than that of pancreatic ribonuclease A--one of the most active RNA-hydrolyzing enzymes.  相似文献   
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The paper summarizes the results of over 30-year studies dealt with dyslipidemias and autoimmune diseases. The teaching of the antiphospholipid syndrome (APS) has aroused interest in the problem. The experience gained shows changes in the blood cholesterol transport system. Patients with systemic lupus erythematosus (SLE) have higher levels of low density lipoprotein cholesterol and lower concentrations of high density lipoprotein (HDL) cholesterol, apolipoprotein A than the controls. The quantitative and qualitative changes in particles result in decreased acceptance of cholesterol from the membrane of a cell and tissues, which promotes the development of vascular diseases. Lipoprotein (a) may be an additional risk factor for thrombosis chiefly of coronary arteries, in patients with SLE and APS. Increased levels of oxidized low density proteins having atherogenic activity were found mainly in patients with SLE. The use of corticosteroids causes the changes in the spectrum of blood lipids, which together with other factors (thrombosis, vasculopathy, thrombocytopenia, etc.) create good conditions for the development of atherosclerosis, which determines the necessity of correcting the parameters of blood lipid transport not only to prevent vascular disorders but to improve the general life prognosis in SLE patients.  相似文献   
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To determine the effect of life-long alcohol consumption on the adult and aged rat model, 4-week-old, female Sprague-Dawley rats were divided into three diet groups. Alcohol-treated animals were fed a modified Lieber-DeCarli diet ad libitum containing 35% ethanol-derived calories, whereas the pair-fed animals (weight-matched to ethanol rats) received an isocaloric liquid diet in which maltose-dextrin substituted calories supplied by ethanol. Chow animals were fed a standard rat chow ad libitum. Proximal tibiae (primarily cancellous bone) and femora (primarily cortical bone) were removed for analysis after 3, 6, 9, 12, or 18 months on the diets. Serum was collected for analysis of calcium levels, the calcium regulating hormones; parathyroid hormone, 25-hydroxyvitamin D, calcitonin, corticosterone, estradiol, testosterone, and IGF-1. Creatinine, SGOT/AST, and SGPT/ALT levels were measured to determine kidney and liver integrity. Previous studies, with young animals, showed that chronic alcohol consumption during the age of bone development reduced bone density and bone mass in both cortical and cancellous bone. The present study demonstrates that these reductions last throughout life, whereas morphological values, such as length and diameter, attain control levels. Calcium regulating hormones and sex hormones are essentially normal and do not appear to be the primary causative agent for adult alcohol-induced osteopenia, but it appears to be due to a more direct effect of alcohol on bone cells.  相似文献   
84.
OBJECTIVES: The objectives of the study were to assess the suitability of a service for provision of emergency hormonal contraception by nurses. METHODS: Retrospective analysis was carried out of data obtained from the case records of 500 consecutive women who attended ABACUS (a city center-based family planning clinic in Liverpool, UK) for emergency contraception during the 7th and 9th months of the first year (1994) of the service. Similar data were collected for 100 consecutive women during 1 month of the third year (June 1996). The number of women who received emergency hormonal contraception was noted. In particular, details pertaining to the reasons for referral to the doctor and the trend of referrals were noted. RESULTS: The results indicate that during the first year the nurses independently issued emergency hormonal contraception to 37% of the women. They referred the remaining 63% to the medical staff. One-third of referrals were for ongoing contraception, especially oral contraception. Another third of referrals appeared to be due to 'nurse anxiety', as no medical or other cause was found for these referrals. During the third year, nurses dispensed emergency hormonal contraception to 64% of women. Among the remaining 36% of women who were referred to the doctor, 19% needed hormonal contraception. Referral reflecting 'nurse anxiety' significantly declined (1%) compared to the first year of service. CONCLUSIONS: Ongoing contraception, particularly initiation of oral contraception, was one of the main reasons for referral during the first year. Referral due to 'nurse anxiety' significantly declined with continued experience and may have reflected initial anxiety and the learning curve. With increased experience over the first 2 years, the outcome of this service showed encouraging improvement. The nurses now dispense emergency hormonal contraception to a majority of women.  相似文献   
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More than 600 cases of ovarian tumors were analyzed for histological type, age of patient, bilateral occurrence, mobility and malignant degeneration in restant ovaries. Tumors of germinal epithelial origin show the highest incidence (24%) of malignant degeneration, tumors of germ cells the lowest (3,5%). Incidence of malignant degeneration increases in relation to the age of the patient from 2% (and under 30 years) to 36,5% (60-70 years). Each form of tumor has its typical age peak, which is about 20 years higher for carcinomas than for their benign counterpart. Bilateral ovarian tumors are malignant in 29%, one-sided only in 13%. Among freely movable ovarian tumors, only 6% enclose a malignant tumor, among adhaerent ones 34%. The examination of the prognosis of granulosacell-tumors, dysgerminomas and teratoblastomas is based on a larger material.  相似文献   
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