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21.
Congenital malformations among children of women working with video display terminals 总被引:1,自引:0,他引:1
In a case-base study among 214,108 commercial and clerical employees in Denmark the potential effect of the use of video display terminals on the risk of congenital malformations in pregnancy was investigated. The study base was identified by means of register linkage of the Medical Birth Register and the National Register of In-Patients. In the source population 24,352 pregnancy outcomes were registered, 661 of which with congenital malformations entered the case group, and a base sample of 2252 pregnancies was drawn. Data concerning the use of video display terminals, job stress, ergonomic factors, exposure to organic solvents, and life-style factors were obtained from postal questionnaires. The results of this study did not support the hypothesis that the use of video display terminals during pregnancy is associated with an increased risk of congenital malformations. 相似文献
22.
The effect of angiotensin-II (A-II) was studied on ring segments of the terminal extraocular branches of the posterior ciliary artery isolated from human enucleated eyes. It induced a potent concentration-dependent contraction on top of the spontaneous myogenic tone of all arteries studied from five patients with the concentration required to give half-maximal response equal to 51 nM. The spontaneous tone and maximal increase in vessel wall tension induced by A-II was equal to 51% of Emax. The relative response and sensitivity to A-II was unchanged in three endothelial denuded vessels, but the spontaneous tone increased. The arteries became completely insensitive to A-II after one exposure. These results show an immediate direct contractile effect of A-II on human posterior ciliary arteries, but the development of pronounced tachyphylaxis indicates that A-II is probably not an important factor in reducing blood flow to the optic nerve head. 相似文献
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24.
Molecular identification of a small supernumerary marker chromosome by in situ hybridization: diagnosis of an isochromosome 18p with probe L1.84 总被引:1,自引:0,他引:1
A dysmorphic child was found by cytogenetic analysis to have an extra small marker chromosome. The marker chromosome was shown to possess a chromosome 18 centromere by in situ hybridization, and probably represents an isochromosome 18p. Centromere specific probes should be of value in identifying extra small marker chromosomes, and thereby provide better understanding of the clinical significance of these. 相似文献
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26.
Kundel HL; Gefter W; Aronchick J; Miller W Jr; Hatabu H; Whitfill CH; Miller W Sr 《Radiology》1997,205(3):859
27.
A Andreasen A M Drewes J E Assentoft N E Larsen H Nielsen I E Holm F A Geneser 《Journal of neuroscience methods》1991,37(2):151-160
A large series of rabbit hippocampal Neo-Timm stained sections were manually aligned, digitized, and by a modified median filtration noise reduced and reconstructed into a three-dimensional object. From the presented simulated grey tone cuts of this object, the reader may assemble a rabbit hippocampal model, that spatially illustrates its anatomy. 相似文献
28.
Pinacidil uptake and effects in the isolated rabbit heart 总被引:1,自引:0,他引:1
The myocardial accumulation of pinacidil showed one-compartment characteristics with a half-time of 1.11 min., whereas the disposition followed three-compartment kinetics with half-times for the relevant two redistributory and the terminal phases of 0.39, 1.51 and 5.44 min., respectively. At a steady-state drug concentration in the perfusate of 6.12 nmol ml-1, the average concentration of pinacidil in the myocardium was 20.6 nmol g-1. The accumulated amount could predictically be referred with 57% to a central and 31 and 12% to two peripheral (deeper) drug pools. The pharmacodynamic effects of pinacidil in the isolated perfused rabbit heart were studied at stepwise increasing concentrations from 0.15 to 100 microM. Coronary flowrate increased initially up to 24.5% at 1.5 microM pinacidil and then gradually decreased. Amplitude and velocity of contraction were both inhibited in a biphasic way up to 92.7 and 94.1%, respectively. Apparent dynamic steady states developed within 13-15 min. The computer-derived inhibitory Em-values related to the first phase were 49.2 and 52.4% and those related to the second phase were 111.7 and 108.3%, respectively. Heart frequency decreased monophasically and exhibited an inhibitory Em-value of 19.6%. Oxygen consumption decreased at pinacidil concentrations higher than 15 microM and the Em-value was 69.7%. The frequency-corrected QT-interval decreased biphasically and the related inhibitory Em-values were 8.6 and 58.7%. The QRS-interval did not change and the PQ-interval only showed a minor increase at the highest pinacidil concentration. Our findings are compatible with the concept of pinacidil being a potassium channel opener. 相似文献
29.
30.
E J Nielsen 《Annals of emergency medicine》1992,21(7):880-882
Tropical pyomyositis, though common in Africa, South America, and the South Pacific, is relatively rare in North America. Reported is the case of a patient who developed chest wall muscle abscesses after sustaining minor chest wall muscle trauma and presented to the emergency department appearing acutely ill. He was treated surgically with irrigation and debridement of the abscesses as well as with antibiotics and recovered fully over a seven-month course. This case illustrates important aspects of tropical pyomyositis with a discussion of the natural history of this disease as well as diagnostic modalities and treatment options for this virulent infectious process that is usually caused by penicillin-resistant Staphylococcus aureus. 相似文献