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41.
Hodgkin's disease (HD) was diagnosed in 24 patients who were either seropositive for human immunodeficiency virus (HIV) (21) or members of a high-risk group (three), but had not developed acquired immune deficiency syndrome (AIDS). Clinical presentation of the disease was characterized by constitutional symptoms in all, especially fever (23/24) and disseminated disease (22/24) at diagnosis. Mediastinal adenopathy was rare. Bone marrow involvement was particularly frequent (12/24), and a positive bone marrow biopsy preceded lymph node biopsy in 5 of the 12. Histopathologic features of these tumors included an increased number of nonlymphoid stromal cells, i.e., histiocytic and/or fibroblastoid. In some tumors these fibrohistiocytoid stromal cells were arranged in bundles, but distinct nodule with birefringent collagen band formation was not observed. Twenty-two patients were treated, most with combination chemotherapy; one was untreated; one, unknown. Sixteen, including the one untreated, died with disease at 3 to 25 months; one died of an unrelated cause; four were alive at 3 to 24 months; three were lost to follow-up. Frequent bone marrow involvement at presentation suggests the usefulness of the bone marrow biopsy for diagnosis in subjects at risk, especially when they present with spiking fever of unknown origin. Contrary to most previous series, virtually all of our cases were of mixed cellularity type, characterized by increased fibrohistiocytoid stromal cells in place of depleting lymphocytes. The classic nodular sclerosing feature with birefringent collagen band formation was not observed. In conclusion, HIV-associated HD was characterized by advanced stage with fever at presentation, preponderance of mixed cellularity histologic type with increased fibrohistiocytoid stromal cells, and poor outcome. Hodgkin's disease in AIDS patients presents an intriguing biological model to study the role of stromal histiocytes in immunodeficient patients.  相似文献   
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We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA.  相似文献   
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OBJECTIVE: Lp(a) lipoprotein is a distinct lipoprotein particle that recently has been found to be associated with cardiovascular disease. A study was conducted to assess the influence of cardiovascular disease risk factors on levels of Lp(a) and to evaluate the effects of age, exercise, and estrogen on these levels. STUDY DESIGN: Two studies, a cross-sectional study of older men (n = 105) and women (n = 75) (mean age 76 years) and a prospective study of younger postmenopausal women (mean age 48 years), were carried out. Lp(a) and other lipoproteins were measured in the two studies and differences were sought by statistical analysis. RESULTS: In the cross-sectional study, serum Lp(a) was similar in men and women and was not influenced by age. Lp(a) levels in men and women were higher when there was more than one cardiovascular disease risk factor present (p less than 0.028). We could not demonstrate such a relationship with other lipid and lipoprotein measurements. In the prospective study exercise alone had no influence on Lp(a) levels. Oral estrogen decreased Lp(a) levels marginally (p = 0.08). The decrease in Lp(a) with oral estrogen was associated with increases in triglycerides (p less than 0.01) and very-low-density lipoprotein (p less than 0.06). CONCLUSIONS: These data confirm that elevated Lp(a) levels are an independent risk factor for cardiovascular disease. Lp(a) levels are primarily influenced by genetic factors and it appears estrogen may have a minor influence on its hepatic synthesis.  相似文献   
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Background: Many studies have addressed the effect of the timing of surgery for breast cancer relative to menstrual cycle phase, with conflicting results. Explanations for the possibility that survival could be altered by the appropriate timing of breast cancer surgery in humans remain speculative. Methods: We examined the expression of three estrogen related proteins (c-erbB-2, cathepsin D, pS2) in the breast tumors from 69 premenopausal women sampled in different phases of the menstrual cycle. Data on S-phase fraction and hormone receptor expression were also analyzed. Immunohistochemical assays were used to measure the proteins of interest. S-phase fraction was determined by flow cytometry. Analyses were performed based on fraction of cells staining positive for the protein, density of stain, and a histoscore that combined both fraction of positive cells and density. Results: We found no differences in c-erbB-2, cathepsin D, hormone receptor, or S-phase levels in tumors sampled in the follicular versus luteal phase, or perimenstrual versus periovulatory phase. The exception was pS2, which was expressed at greater levels during the luteal than during the follicular phase of the cycle (p<0.01); but there was no difference in pS2 expression when the patients were classified as periovulatory versus perimenstrual. Conclusions: Our findings do not support a variation in c-erbB-2, cathepsin D, S-phase fraction, or receptor expression as an explanation for the differences in breast cancer prognosis when surgery is timed by menstrual cycle phase. The finding that pS2 (an indicator of hormone sensitivity, and possibly better prognosis) is expressed at higher levels in tumor samples during the luteal phase suggests that the biologic profile of breast tumors may vary with the menstrual cycle and that these variations deserve further study.  相似文献   
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The physicochemical properties of the upstream and downstream waters from the Upper Ganga canal, discharged cooling tower water, machine washings, and scrubber and bottom ash effluents of a 530 MW Kasimpur coal-fired thermal power plant have been determined, and their effects directly on fertile soil and indirectly on pea (Pisum sativam) and wheat (Triticum aestivum) crops have also been studied. The effluents were found to be alkaline in nature. The scrubber and bottom ash effluent was found to contain large amounts of solids and had high biochemical and chemical oxygen demands. All the effluents were found to be responsible for altering the chemical composition of the soil. The soils irrigated with the different effluents exhibited an increase in pH, organic matter, calcium carbonate, water-soluble salts, cation exchange capacity, electrical conductivity, and nitrogen and phosphorus contents while potassium content decreased, probably due to being leached to the lower layers of the soil. The effects of 100, 50, and 0% (tap water control) dilutions of cooling tower, machine washings, and scrubber and bottom ash effluents on the germination and growth of pea and wheat crops were also monitored. Using the undiluted effluents, there was 100% germination for both the crops when the irrigation was done with cooling tower effluent. The germination was restricted to 90% for the two crops when irrigated with machine washings effluent, and to 80 and 70% for pea and wheat, respectively, when irrigated with scrubber and bottom ash effluent. The samples of upstream and downstream canal water were also used for irrigating soils with and without crop plants in order to ascertain the impact of the effluents on the canal water and its subsequent effect on the crops. The soils irrigated with downstream canal water were found to contain slightly more calcium carbonate, phosphorus, and ammonia-nitrogen than those receiving upstream canal water. Though 100% germination was obtained in both the cases, the growth of the plants irrigated with the downstream canal water was found to be slightly reduced.  相似文献   
50.
A R Khan  M Lemeignan  J Molgo 《Toxicon》1986,24(4):373-384
The effects of Anemonia sulcata toxin II (ATX-II) were studied on mechanical and electrical activities of frog muscle fibres isolated from semitendinosus or tibialis anterior muscles of Rana temporaria (2.8-7.7 degrees C). In concentrations ranging between 7.7 and 100 microM, ATX-II greatly potentiated the isometric twitch of single muscle fibres in a time-dependent manner. Increase in twitch amplitude by ATX-II was associated with an increase in time to peak tension and time from peak tension to half relaxation. ATX-II caused no change in maximum force production during fused tetanus, but the tension was maintained for several seconds after the cessation of stimulation. Such long tetanic contractions were also obtained in low-Na Ringer solution, but their duration was somewhat shorter. No specific action of ATX-II was detected on relaxation kinetics during a tetanus. The twitch potentiating effect of ATX-II was markedly increased by 3,4-diaminopyridine. Action potentials recorded from single muscle fibres in the presence of ATX-II showed a delayed onset of repolarization with a reduced rate of fall. In addition, ATX-II caused repetitive spontaneous firing of action potentials after the cessation of tetanic stimulation. ATX-II (3.3 - 10 microM) also increased action potential duration by reducing the rate of repolarization in surface fibres of formamide-treated sartorius or cutaneous pectoris muscles (20 degrees C) stimulated indirectly or directly. The potentiation of twitch force and the prolongation of contractions caused by tetanic stimulation can be attributed to the membrane action of ATX-II, which leads to prolongation of action potentials, to repetitive muscle firing and to the appearance of plateau potentials.  相似文献   
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