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991.
The light microscopy and ultrastructure of a malignant epithelioid schwannoma are described. Characteristic cells resembling perineural elements with various degrees of differentiation were observed. Primitive epithelioid cells contained scant ergastoplasm, and few tubules and filaments, but did have abundant free ribosomes and Golgi membranes. Also noted were junctional complexes and focal fusion of plasma membranes, basal laminae were absent. Better differentiated cells were completely limited by a well-developed basal membrane and had an abundance of intracytoplasmic filaments and multiple pinocytotic vesicles. The intercellular ground substance was composed of numerous fine collagen fibrils and amorphous, basement membrane-like, electron-dense material. A striking ultrastructural similarity of the tumor cells to those encountered in ethylnitrosourea-induced malignant schwannomas in rats was noteworthy. 相似文献
992.
993.
MM Mirrakhimov GN Prizhivo?t ZhA Chotoev AG Rachkov 《Canadian Metallurgical Quarterly》1977,84(10):421-423
It was shown in man and rabbits that a 30-minute inhalation of a 100% O2 under normal atmospheric pressure was accompanied by an elevation of the blood coagulation capacity and a sharp reduction of the count of platelets with the change of their structure. The trigger mechanism of the described hypercoagulation effect is possibly the viscous metamorphosis of platelets developing under the effect of oxygen activation of Hageman's factor. 相似文献
994.
MM Kirsh DM Behrendt MB Orringer O Gago LA Gray LJ Mills JF Walter H Sloan 《Canadian Metallurgical Quarterly》1976,184(3):308-316
Forty-three patients with aortic rupture secondardy to blunt trauma have been treated at the University of Micigan within the past 10 years with an overall salvage rate of 70%. The diagnosis should be suspected in anyone who has sustained a high speed decelerating injury, if the chest roentgenogram shows media-stinal widening, whether or not there is hypertension of the upper extremities; systolic murmur, or external evidence of chest injury. Aortography should be employed to confirm the diagnosis and to determine the site or sites of rupture. Repair of the lesion should be undertaken as soon as possible and takes priority in most instances over associated injuries. Repair in almost all cases can be accomplished safely and quickly using a bypass shunt without the aid of extracorporeal circulation. 相似文献
995.
In fifteen hyperthyroid patients treated for 5 or more consecutive years with propylthiouracil four or more yearly prognostic 'suppression' tests (Cassidy & VanderLaan, 1960) were done. In nine of the fifteen patients there was a progressive diminution over a period of 3-6 years in the values of these suppressed uptakes to 20% or below. Eight of these nine patients have remained euthyroid off therapy for 1-8 years (average 3-1 years). None have become hypothyroid. The data suggest a gradual continuing change in thyroid function over the course of years in some hyperthyroid patients on antithyroid therapy. This may be a long-term effect of the drug and may have prognostic significance. 相似文献
996.
During the five-year period 1964-68 96 733 births were registered in the 28 hospitals equipped with maternity facilities in the Uppsala hospital region. Of these babies, 1 636 were born in 818 twin deliveries. Data on gestational age, sex, weight and length at birth, birth order, hospital type, congenital malformations and perinatal mortality are analysed. Altogether 17.3 per 1 000 of the children born during this period were born in multiple births. The perinatal mortality for the twin babies was 64 per 1 000 born, with the mortality higher in the less specialized hospitals than the others. Twin no. 1 suffered perinatal death in 67 cases per 1 000 and twin no. 2 in 60 cases per 1 000. For twins of primiparae the losses were 92 per 1 000 children and for twins born to multiparae 51 per 1 000. Altogether 72 per 1 000 male twins died perinatally compared to 52 per 1 000 female twins. The most heavy losses occurred among the low-weight premature twins and in these cases both twins often suffered perinatal death. 相似文献
997.
Rat liver and kidney slices were incubated at 37 degrees C for 1 h in 1.0 ml of Krebs-HCO3 buffer containing 10mM glucose and one of the following: 5 mM [8-14C]ATP, 5 mM [8-14C]ADP, 5 mM [8-14C]AMP, or 5 mM [8-14C]ation medium and tissue extract were subjected to electrophoretic separation and the radioactivity present in ATP, ADP, AMP, IMP, inosine, adenosine, and hypoxanthine was counted. Extensive degradation of the added nucleotide was observed in the presence of both tissues. The concentrations of 14C-labeled ATP and ADP found in the liver and kidney indicated that these compounds were present within the cells. Evidence is presented which suggests that ATP, and to a lesser extent ADP, entered the liver and kidney as such and were not synthesized within the cell from 14C-labeled adenosine. 相似文献
998.
999.
1000.
MM Chartier C Milet E Lopez F Lallier E Martelly S Warrot 《Canadian Metallurgical Quarterly》1977,73(1):23-36
In the silver female eel (Anguilla anguilla L.) maintained in fresh water, surgical removal of Stannius corpuscles (SC) resulted in: a) A significant increase of wet weight of gill cells and the dry weight of gill filaments expressed as function of body weight. b) A proliferation and a hypertrophy of chloride cells shown by a significant rise of cell volume expressed as a precentage of the epithelial volume. c) An increase of the calcium (Ca) binding protein activity in the total branchial mucosa. These modifications are not observed when eels are maintained in Ca-free water. The results are discussed in relation to the Ca fluxes across gills in eels deprived of SC and gill morphological changes during sea water adaptation. 相似文献