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201.
In three cases of oligodendrogliomas, atypical cells rich in eosinophilic cytoplasm, resembling plump astroyctic or astroblastic cells, were studied under the electron microscopy. These cells showed finely granular cytoplasm with routine hematoxylin-eosin preparation; ultrastructurally, they exhibited abundant, round cytoplasmic bodies of autophagic-vacuole type, in addition to other fine structures characteristic of oligodendroglioma cells. 相似文献
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CL Gugliucci MJ O''Sullivan W opperman M Gordon ML Stone 《Canadian Metallurgical Quarterly》1976,125(4):435-441
Over the last 2 years at Metropolitan Hospital Medical Center 245 diabetic women have been seen on the obstetric service. This complication of pregnancy comprises 7.9 per cent of 3,076 deliveries, resulting in an over-all uncorrected perinatal mortality rate of 2.9 per cent. We believe that early detection and strict rigid control of diabetes is the key to improved perinatal outcome. This article presents the classification, diagnosis, and management which have led to these results. 相似文献
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Fluorescence has been suggested as a method with which to detect and identify bacterial spores. To better understand the nature of the fluorescence signal, we observed the intrinsic steady-state fluorescence and phosphorescence spectra of Bacillus globigii (BG) in both dried and aqueous forms. In vitro, dried, and suspension forms of BG were measured at room temperature in 300-600-nm excitation wavelengths. Also, the phosphorescence of dry BG spores was measured at room temperature at 300-600-nm excitation wavelengths. The wet BG spores exhibited a strong maximum in their fluorescence spectrum, with the peak excitation wavelength near 300 nm and emission wavelength near 400 nm. When the BG was dried, this peak shifted to an approximately 450-nm excitation maximum and an 500-nm emission maximum. The difference between the wet and the dry spore fluorescence spectra cannot be explained by the phosphorescence of the dry spores. Other changes must take place when the spores are wet to account for the large changes observed in the spectrum. 相似文献
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ML Nochomovitz AF Dimarco JT Mortimer NS Cherniack 《Canadian Metallurgical Quarterly》1983,127(3):325-329
We studied in 10 supine anesthetized dogs diaphragm contraction produced by electrical activation with intramuscular electrodes surgically implanted in the ventral surface of the diaphragm and compared this with activation of the ipsilateral phrenic nerve (C5, 6, and 7) before it entered the thorax. Repetitive 40-Hz pulse trains with supramaximal current stimulus were used after hyperventilation of the animals to apnea. A single intramuscular electrode within 1 to 2 cm of the site of phrenic nerve entry into the diaphragm produced a mean transdiaphragmatic pressure of 12.0 cm H2O +/- 0.97 SE and mean tidal volume of 0.27 L +/- 0.04 SE. Mean values observed with phrenic nerve stimulation were not statistically different, and both electrode systems produced equivalent outward abdominal motion and upper rib cage paradox, as monitored by inductive plethysmography. There was no difference in gas exchange during stimulation with a single hemidiaphragm electrode and mechanical ventilation compared at the same tidal volume and respiratory rate. Blockade of neuromuscular transmission with curare eliminated intramuscular and phrenic nerve stimulation proportionately, suggesting that activation of the diaphragm is dependent in both cases on the phrenic nerve. This technique does not entail manipulation of the phrenic nerve and may have clinical application as an alternative technique for diaphragm pacing. 相似文献
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The time course of skin tumor induction was determined in hair-clipped inbred agouti C3Hf mice irradiated three times per week with a medium-pressure quartz-mercury lamp; 4 different UV doses were used. Although the ears were also exposed to the radiation, in the 3 groups given the highest doses no ear tumors were observed by the time each animal had developed at least 1 tumor on its back. No tumors were found in the animals receiving the lowest UV dose. In the group receiving the highest dose, males developed tumors earlier than did females; this trend continued in the lower dose groups. Many tumors that developed in the back skin were well-differentiated squamous cell carcinomas. Others were less well-differentiated squamous cell carcinomas. Others were less well defined so that the cell of origin was difficult to determine. In the group receiving the highest UV dose, the squamous cell carcinomas were few, whereas at the lower doses they predominated. 相似文献
210.
Reviews the book, Aesthetics and Psychobiology by D. E. Berlyne (see record 1973-00821-000). Progress in the aesthetic disciplines has been at a snail's pace. Berlyne charges six factors with having impeded advance: the belief in art as a supernatural phenomenon, the failure to separate factual from normative questions, the conception of art as a unitary phenomenon, the habit of treating art in isolation from nonartistic forms of behavior, the preoccupation with uniqueness in aesthetic taste, and the concentration on verbal judgments in aesthetic work. But the future looks brighter, due primarily to the following developments: (1) the rise of information theory, which provides procedures for rigorously analyzing some of the features of stimulus patterns that most concern aesthetics, (2) recent empirical and theoretical contributions in both psychology and neurophysiology to the understanding of pleasure and arousal, and (3) findings bearing on the nature of exploratory behavior, both in animals and humans, particularly as these teach the motivational importance of such elements as complexity, novelty and uncertainty, so-called "collative" variables, that "seem to be identifiable with the irreducibly essential ingredients of art and of whatever else is aesthetically appealing" (viii). The principal aim of Berlyne's book is to establish the ground gained in these three areas, compare it to the contributions made by earlier workers, and effectuate "a provisional synthesis that will at least bring key problems to the fore" (viii). It is a formidable task. Inevitably, the effort fares better in some assignments than others. Ironically, what discrepancies in quality do exist would probably project less were Berlyne not so knowledgeable about his subject matter. He is, quite obviously, in the tradition of those "cultured gentlemen" with whom he is wont to populate the early history of psychological science. Parenthetically, one suspects that he could supplement the present work with a very creditable companion volume in the philosophy of aesthetics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献