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81.
Amiodarone hydrochloride is a potent antiarrhythmic agent recently approved for use by the Food and Drug Administration. Anterior subcapsular lens opacities were observed in seven of fourteen patients treated with moderate to high doses of amiodarone at the Veterans Administration Medical Center in San Francisco in 1982. The present report summarizes the present status of these same fourteen patients ten years later. Anterior subcapsular lens opacities developed or progressed in all patients continuing treatment with this antiarrhythmic agent during the following ten year interval. Although Snellen visual acuities are not decreased, subtle visual impairment is present as measured by contrast sensitivity measurements with and without glare. This decrease in visual acuity is not a contraindication for therapy with this potentially life saving drug.  相似文献   
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Background  

A total of 137 consecutive patients with recent uncomplicated myocardial infarction (n=31) or unstable angina (n=106) were studied to determine the relative prognostic value of predischarge clinical risk stratification and intravenous dipyridamole stress sestamibi (MIBI) myocardial tomography in patients unable to exercise maximally after an acute ischemic coronary event.  相似文献   
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This paper summarizes the findings of the Cadmibel Study, a cross-sectional population study of the health effects of cadmium, but only with respect to the cardiovascular system and calcium metabolism. The study disproved the hypothesis that exposure to cadmium would lead to an increase in blood pressure and in the prevalence of hypertension and other cardiovascular diseases. On the other hand, there was a positive relationship between urinary cadmium (Cd-U) and both serum alkaline phosphatase activity and urinary excretion of calcium. The regression coefficients obtained after adjustment for significant co-variates indicated that, when Cd-U increased two-fold, serum alkaline phosphatase and urinary calcium rose by 4% and 0.25 mmol/24 h, respectively. These findings suggest that calcium metabolism is gradually affected as cadmium accumulates in the body. The morbidity associated with the latter phenomenon is still unknown, and requires further investigation, preferably in a longitudinal prospective population study, in which the incidence of morbid events would be monitored in relation to the cadmium body burden.  相似文献   
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The effect of human recombinant interleukin-2 (IL-2) and human recombinant granulocyte-macrophage colony-stimulating factor on the growth of a virulent strain of Escherichia coli in tissue culture medium and in untreated, normal mouse serum was investigated. Both of these cytokines enhanced the growth of the microorganism two- to threefold in tissue culture medium with or without additional fetal calf serum and in untreated mouse serum. IL-4 did not have any effect on the growth of this microbe under the conditions tested. That the enhancement of growth seen with recombinant IL-2 was due to the active cytokine was shown by the following data: (i) addition of an antibody to IL-2 abrogated the growth-promoting effect; (ii) the excipient buffer, which contained everything except the active cytokine, was inactive in modifying bacterial growth; and (iii) heat-inactivated recombinant IL-2 did not promote enhanced microbial growth. The enhancement of growth with IL-2 was significant with concentrations as low as 1 U/ml. Growth of an avirulent strain of E. coli was not stimulated by IL-2. Moreover, addition of IL-2 to growth virulent E. coli in tissue culture medium led to rapid removal of the cytokine from the medium. Collectively, these data suggest that cytokines may act as growth factors for some virulent bacteria.  相似文献   
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The mitochondrial genome of the selfed progeny of a plant regenerated from long-term somatic tissue culture displays specific structural rearrangements characterized by the appearance of novel restriction fragments. A mitochondrial DNA library was constructed from this selfed progeny in the SalI site of cosmid pHC79 and the novel fragments were subsequently studied. They were shown to arise from reciprocal recombination events involving DNA sequences present in the parental plant. The regions of recombination were sequenced and the nucleotide sequences were aligned with those of the presumptive parental fragments. We characterized an imperfect short repeated DNA sequence, 242 bp long, within which a 7-bb DNA repeat could act as a region of recombination. The use of PCR technology allowed us to show that these fragments were present in both parental plants and tissue cultures as low-abundance sequence arrangements.  相似文献   
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