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991.
With the progressive discharge of porous lead dioxide electrodes the PbO2 content decreases and that of PbSO4 increases correspondingly. If 相似文献
992.
RD Adams 《Canadian Metallurgical Quarterly》1975,(35):135-137
Diverticulation of the lateral ventricles of the brain has received little attention in the literature on hydrocephalus. From clinical observations on one child and one adult with diverticulation, it is apparent that force of CSF within the diverticulum is greater than that against the normal parts of the ventricular wall. In both cases, regression of focal symptoms occurred after insertion of a shunt. 相似文献
993.
RD Stewart CL Hake A Wu TA Stewart JH Kalbfleisch 《Canadian Metallurgical Quarterly》1976,31(6):280-285
An 18% reduction in the carboxyhemoglobin (HbCO) saturation in nonsmoking Chicago blood donors occurred between 1970 and 1974, indicating that current donors are being exposed to a lower average carbon monoxide (CO) concentration than had been experienced by 1970 donors. In contrast to the situation in 1970, when it was discovered that 74% of the nonsmokers in Chicago were being exposed to CO in excess of the amount permitted by the federal air quality standards, in 1974 only 41% of the nonsmokers were being overexposed. The observed reduction in HbCO correlates well with both the ambient CO levels recorded at the air monitoring stations and the reduction in CO emission from automobiles. If the current trend continues, Chicago should reach compliance with air quality standards for CO by 1985. The measurement of HbCO in a representative urban population is an accurate index of actual CO exposure and supplements the air pollution data provided by air monitoring stations. 相似文献
994.
995.
Serial carcinoembryonic antigen (CEA) assays were conducted in patients with endocrine-unresponsive prostatic adenocarcinoma who were being treated with multidrug chemotherapy. Changes in CEA correlated with the clinical status of the patient in 70 per cent of the determinations and were more accurate than acid phosphatase in monitoring the response to treatment. 相似文献
996.
Superior collicular fragments transplanted from fetal to newborn rat brains develop complex internal organization and receive visual afferents from the host providing they lie sufficiently close to the host visual pathways. This system allows investigation in vivo of special affinities between cells of the mammalian central nervous system. 相似文献
997.
998.
999.
This letter shows the independence of the matrix products (CAiB, i = 1, 2, ?) from any state-space realisation of the infinite number of possible realisations1,2 of a transfer-function matrix Z (s). In addition, it shows that, in the sequnce (Z1, Z2, ?) derived from Z(s), only the first M can be linearly independent, where M is the degree of the minimum polynomial of A. 相似文献
1000.