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An analysis of causes of the development of external enteric fistulas in 71 patients, who to the moment of surgery showed no purulent-inflammatory processes in the abdomen, has demonstrated that in most patients (40 persons) the fistula development can be related with technical errors (an injury, deserosing, suturing of the intestine) during an operation. It is believed that for prophylaxis of enteric fistulas a special care should be given by a surgeon to mobilization of the intestine from adhesions, strict observation of technical recommendations and tactical purposes pertaining to treatment of acute intestinal obstruction, strangulated hernias, etc. 相似文献
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The proton magnetic resonance (PMR) and phosphorus magnetic resonance (PhMR) spectra of egg phosphatidylcholine in the presence of 1-anilino-8-nahthalenesulfonate (ANS) have been studied. At low ratios of ANS to phospholipid, the spectra indicate that ANS molecules are in the lipid interface region where they interact with the head-group protons. ANS also penetrates into the hydrocarbon region to some extent. As the ANS/phospholipid ratio approaches one, a significant splitting of the head-group signal occurs. This splitting is associated with head-group signals from inner and outer molecules of the phospholipid vesicles. As the ANS/phospholipid ratio is further increased, a gel phase often occurs. The spectra for this gel phase suggest a highly mobile head-group. Further ANS addition results in a PMR spectrum suggestive of ANS-phospholipid micelle formation. The results for a phospholipid-cholesterol complex and for the total lipid extract from a cell membrane show that the ANS effect is more complicated in these cases. 相似文献
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TN Parks 《Canadian Metallurgical Quarterly》1979,183(3):665-677
The effects of embryonic deafferentation on the morphological development of the avian cochlear nuclei, n. angularis (NA) and n. magnocellularis (NM), were investigated. The right otocyst was surgically removed from chick embryos at 55 to 60 hours of incubation and the subsequent development of total volume, neuron number, and neuron cross-sectional area were studied with quantitative methods in animals sacrificed at 2-day intervals between embryonic days 9 and 19 and at 28 days posthatching. The development of NA and NM is severely affected by otocyst ablation. Between embryonic days 9 and 19, a large group of NA neurons in the medioventral portion of the nucleus on the operated side moves to an ectopic ventromedial position, while the remainder of this nucleus stays in its normal dorsolateral position. Beginning about day 13 of incubation, the normal increase in the volume of NA and the size of its neurons becomes progressively retarded and 40% of its neurons are lost. The growth of NM is also retarded after day 11 of incubation and the growth of mean neuron size is retarded after day 15. There is a 30% loss of neurons in NM which begins after embryonic day 11. The results indicate the primary cochlear fibers make a critical contribution to the growth and maintenance of their target neurons. The absence of this facilitative influence following otocyst ablation becomes apparent just at the time synapses would normally be formed between the the primary auditory afferents and the brain stem auditory neurons. The abnormal movement of neurons in nucleus angularis to an ectopic position after otocyst ablation suggests that primary auditory afferents may serve to stabilize the position of their target cells within the developing brain. 相似文献
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D Hassler M Maiwald TN Petney 《Canadian Metallurgical Quarterly》1998,280(12):1049-50; author reply 1051