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951.
V. V. Veremey A. A. Kostenko I. K. Kuz'michev A. E. Poyedinchuk G. I. Khlopov 《Journal of Infrared, Millimeter and Terahertz Waves》1994,15(7):1283-1295
Reported here are the results on level and structure of the radiated field of an open resonator at and off resonance. On the basis of the modelling problem rigorous solution and the measurements at 4-millimeter wavelength we find there are no ways to compensate the radiated field from an open electromagnetic structure at resonance. Analysis of open resonator excitation efficiency shows that the mismatch loss of a slot-fed open resonator runs to 34% while at the aperture-feed excitation this is not more than 6% for the same-geometry resonator. 相似文献
952.
953.
954.
V. E. Sokolovich 《Soil Mechanics and Foundation Engineering》1994,31(2):74-76
This article reports on pollution of the environment with dioxins, which are lethal to the human organism. Dioxins are formed
as a by-product at chemical plants with antiquated technologies. Entering into primitive slime pits with wastes, dioxin freely
penetrates into surrounding soils and groundwater. Favorable conditions for formation of dioxins are created when soils containing
chlorinated benzene and phenols are stabilized. The status of this problem abroad is described. Specific measures are suggested
to eliminate dioxins in soils and in slime pits.
Scientific Research Institute of Foundations and Underground Structures. Translated from Osnovaniya. Fundamenty i Mekhanika
Gruntov, No. 2, pp. 27–29, March–April, 1994. 相似文献
955.
Five cases identified in the course of medicolegal reviews are described where the umbilical cord wrapped around the neck of the foetus once was cut intentionally, or broken, prior to the extraction of the body. Delivery was delayed on account of shoulder dystocia for a period of time varying from three to seven minutes. All of these infants were born with a low APGAR score. Subsequently, they displayed manifestations of cerebral palsy and two of them also had permanent brachial plexus lesion. This series of incidents indicates that an unexpected arrest of the shoulders may inadvertently compound the problem that the severing of the cord prior to the delivery of the body entails. If, as in the cases presented here, hypoxic brain damage ensues, the severing of the cord may become a suspected causative factor. Our literary review has revealed no reference to severing of the cord having been followed by shoulder dystocia. Along with other instances where similar reviews drew attention to as yet unrecognized clinical phenomena, this unusual cluster of a previously unconsidered type of accident at birth underlines the value of carefully conducted medicolegal reviews as a potential clinical research tool in medicine. 相似文献
956.
Affiliate of the L. Ya. Karpov Scientific-Research Institute of Physical Chemistry. Translated from Atomnaya énergiya, Vol.
76, No. 5, pp. 422–428, May, 1994. 相似文献
957.
Anmar W. Sabri Zainab H. Ali Serwan F. Shawkat Lamia A. Thejar Thaer I. Kassim Khalid A. Rasheed 《河流研究与利用》1993,8(3):237-250
The influences of the Samarra impoundment on the ecology of the downstream sector of the river Tigris are investigated. Zooplankton were collected monthly from July 1987 to July 1988. It was found that zooplankton were most abundant during high river discharges in March. During the month of low river discharge, September, the zooplankton population was greatly reduced immediately below the barrage and remained so to the last downstream station. Several factors seem to explain such differences. The high discharge from the impoundment was found to be the dominating factor and may flush the small backwaters in which zooplankton were abundant, thus increasing the population in the river. Zooplankton species vary in their ability to sustain populations in the river, variations which are due mainly to species-specific characteristics. 相似文献
958.
The expression of several markers of epithelial cell proliferation was analyzed to establish baseline data for future chemoprevention studies of oral premalignant lesions. Punch biopsies (n = 60) from three different sites of oral mucosa (bucca, lateral tongue, and the floor of the mouth) were obtained from 20 normal donors of both sexes. After formaldehyde fixation and paraffin embedding, immunohistochemistry was used to detect the proliferation markers Mib-1, cyclin D1, and centromere-associated protein CENP-F. Analysis of sections stained for the three markers showed similar patterns, i.e., a low labeling index (LI) in the basal layer and a high LI in the parabasal layer at all three intraoral sites. No proliferative activity was seen above the parabasal layer (superficial layer). All sites showed similar Mib-1 LI values for the proliferative markers. The tongue epithelium exhibited higher parabasal LIs of cyclin D1 and CENP-F than did the other two sites. No significant differences were detected between smokers and nonsmokers. The data from normal mucosa were compared with those from low (n = 30)- and high (n = 17)-grade dysplastic leukoplakias. The Mib-1 LI showed a very significant change, with a 9-fold increase in the basal layer LI in dysplastic leukoplakias. Cyclin D1 and CENP-F showed similar trends with increments of up to 7-fold in the basal layer of high-grade dysplasia. Although the proliferative activity of the parabasal layer was similar in normal and leukoplakic epithelia, the superficial layer showed a significant increment in proliferative activity mainly in high-grade leukoplakia. These studies suggest that proliferation markers in the basal and superficial cells of premalignant lesions may serve as surrogate end point biomarkers for chemoprevention trials. 相似文献
959.
960.
K Kimura K Ezoe H Yokozeki I Katayama K Nishioka 《Canadian Metallurgical Quarterly》1996,23(7):479-483
A 73-year-old male developed disseminated erythema over his entire body after exposure to indeloxazine hydrochloride, a cerebral activator. Patch testing with indeloxazine hydrochloride showed a positive reaction, and plaques, vesicles and pustules developed on the face after the patch test. These had the pathologic feature of eosinophilic pustular folliculitis (EPF, Ofuji's disease). A challenge test also provoked eruptions on the face, trunk, arms and legs, which were compatible with EPF. Moreover, both the patch and challenge tests with indeloxazine hydrochloride induced eosinophilia. This is the first report of drug allergy-induced EPF, where drug sensitivity induced an abnormal eosinophilic response mimicking EPF. 相似文献