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71.
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography. 相似文献
72.
Based on serially cut 200-microns-thick sections from 21 human mandibular third molars, a quantitative characterization was made of the morphology in the mesial and distal interlobal groove. Two parameters were used: depth of interlobal groove and structure angle. The interlobal groove depth varied between 0.13 and 0.55, taken in relation to the maximum crown height. The structure angle varied between 2 degrees and 170 degrees. If the structure angle was less than or equal to 25 degrees, the interlobal groove was classified as a fissure; if the angle was greater than 25 degrees, the interlobal groove was classified as a groove. Only in 18% of the sections did the interlobal groove manifest itself as a fissure. The study demonstrates that it was possible unambiguously to describe the two-dimensional profile of interlobal grooves by groove depth and structure angle. 相似文献
73.
Using nine serially sectioned germectomized mandibular third molars it was possible to examine light microscopical (LM) and transmission-electron microscopical (TEM) features of maturing human enamel organ cells. The degree of enamel mineralization was estimated by quantitative imbibition studies in polarized light. It was possible to distinguish between three progressive stages of enamel mineralization. The most advanced stage was characterized by external enamel porosity. In the least advanced stages the enamel porosity appeared more extensive beneath a less porous surface layer. Ruffle- and smooth-ended ameloblasts were identified corresponding to the maturing enamel. Smooth-ended ameloblasts were the most frequently observed. However, no preferences for one of the two cell types could be observed in relation to the different stages of enamel mineralization. The maturing human enamel organ cells broadly revealed the same characteristics with respect to morphology features, intracellular organization, and junctional complexes as described in the maturation zone of the rat incisor enamel organ. Our findings therefore add to the view that the basic pattern of amelogenesis is identical in human and rat incisor enamel. 相似文献
74.
Summary Estramustine phosphate, an estradiol-mustard conjugate, was shown to reversibly inhibit a stage during the first hour of productive adenovirus 2 infection of HeLa cells. This drug, employed in the therapy of advanced prostatic cancer, specifically interacts with microtubule-associated proteins (MAPs) of the cytoskeleton. The results obtained under physiological conditions in vivo suggest a MAPs-interference with the microtubule-mediated vectorial migration of the virus inoculum to the nucleus. Virus attachment, uncoating kinetics and the appearance of established uncoating intermediates were not affected. 相似文献
75.
Diurnal fluoride concentration in whole saliva in children living in a high- and a low-fluoride area
Salivary fluoride concentrations were investigated in 12-year-old children living in areas with low (0.1 ppm) or high (1.2 ppm) fluoride concentration in the drinking water. Unstimulated whole saliva was collected from 27 children from the respective areas every 2nd hour for 46 h except during sleep. The mean salivary fluoride concentration was 0.32 +/- 0.013 mumol/l (n = 419) in the low-fluoride (LF) area and 0.87 +/- 0.047 mumol/l (n = 401) in the high-fluoride (HF) area. No significant rhythm could be found for the diurnal variations in the mean or individual salivary fluoride concentrations. However, in the HF area the individual salivary fluoride concentrations fluctuated widely and randomly. 相似文献
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78.
Cyano and amidino flavans, isoflavans and 3(2H)-isoflavenes were synthesized in order to study their in vitro antirhino-virus activity, by comparison with the known corresponding chloro derivatives. The activity of the new compounds was evaluated on rhinovirus 1 B infected HeLa cell cultures by examining their ability to interfere with viral cytopathic effect and with plaque formation. It was found that generally the cyano derivatives behave like the chloro compounds, whereas the amidino derivatives show a lower activity, although always dependent on the position of substituent. 相似文献
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