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121.
I Oesch MA Helikson DW Shermeta GM Hutchins JA Haller 《Canadian Metallurgical Quarterly》1980,15(4):433-436
Replacement of a long segment of esophagus for esophageal atresia or severe stenosis remains a special problem in children. The following studies were designed to test the hypothesis that a section of small bowel without serosa could survive as a free autologous transplant to replace part of the mediastinal esophagus. Laparotomy was performed in 20 adult cats, a loop of small bowel was resected and an end-to-end jejunojejunostomy was completed. The serosa of the resected bowel was removed and the mucosa-muscularis graft was used to replace a segment of the middle esophagus that was resected via a right thoracotomy. The interposed graft was entirely wrapped with adjacent skeletal muscle flaps. Postoperative studies include barium swallow and cine esophagograms, histology and blood vessel casts. Results are presented which show anatomical and functional survival of 16 grafts without blood vessel anastomoses or intrinsic vascular pedicles. 相似文献
122.
A method for the isolation of polytene nuclei from salivary glands cells of the Diptera Rhynchosciara americana is described. The stage-specific morphological pattern of the chromosome is maintained during the isolation. The isolated nuclei show two distinct RNA polymerase activities, namely I and II, characterized on the basis of ionic requirements and alpha-amanitin sensitivity. Studies of the product under the incubation conditions show that the system allows the synthesis of high-molecular weight RNA, beside a low molecular weight peak which may comprise pre-4S and 5S RNAs. Autoradiographic studies carried out in the presence or absence of the toxin alpha-amanitin showed that micronucleoli contain products of RNA polymerase type I activity (ribosomal RNA) and that the DNA puffs are engaged in alpha-amanitin sensitive RNA synthesis and thus are sites of polymerase type II activity. 相似文献
123.
In order to determine whether the basal hypothalamus or the pituitary (or both) is the likely locus of action of the tuberoinfundibular (TI) dopamine neurons, these regions were examined for dopamine and neuroleptic receptors. High affinity receptors for haloperidol and dopamine were found in the rat pituitary while none were detected in rat basal hypothalamus. The relative ability of two neuroleptics, chlorpromazine and haloperidol, to displace (3H)haloperidol from the receptor in monkey pituitary is similar to that for rat striatum. The lack of receptors capable of binding (3H)haloperidol or (3H)dopamine in the basal hypothalamus strongly suggests that the TI neurons do not produce postsynaptic effects in this region. The pituitary receptors for (3H)haloperidol and (3H)dopamine have the characteristics of a functional system. The presence of neuroleptic/dopamine receptors in the pituitary and lack of such receptors in the basal hypothalamus supports the hypothesis that dopamine may act directly as a prolactin release inhibiting factor (PIF) rather than releasing PIF from adjacent nerve terminals in the median eminence. 相似文献
124.
GM Staebler 《Canadian Metallurgical Quarterly》1985,32(10):2604-2614
125.
C Ponté C Dupuis J Rémy P Lequien C Rey B Risbourg GM Brevière 《Canadian Metallurgical Quarterly》1977,34(6):514-526
In the 4 studied patients presenting with an Halasz's syndrome, the disease was complicated since the neonatal period by pulmonary arterial hypertension and heart failure. Three out of the 4 infants rapidly died, one after pneumonectomy. The fourth is surviving and benefitted solely from medical cardiotonic treatment. The pathogenesis of early pulmonary arterial hypertension in Halasz's syndrome is complex. The possibly associated cardiac malformations, the persistance of fetal obstructive hypertension due to the increase of the flow in the left pulmonary artery, the left to right shunt induced by the abnormal venous return and predominantly by the systemic blood supply to the right lung, are responsible, at various degrees, for pulmonary hypertension. Among surgical procedures to be proposed, the simple ligation of abnormal arteries which take their origin from the aorta seems to be preferable to pneumonectomy. 相似文献
126.
127.
The influence of 0, 50, 500 or 5,000 ppm supplemental Zn on productive characteristics, weight change, and serum and organ mineral concentrations of 60 crossbred and purebred Yorkshire gilts was evaluated. Gilts were fed their respective treatment from 30 kg body weight until the completion of two parities. Sows fed 5,000 ppm supplemental Zn weighed significantly less than sows from the other treatments when killed. Serum alkaline phosphatase activity was higher for the sows fed the highest level of Zn in all replications at 10 and 14 mo of age than for sows from the other treatments. Sows fed 0, 50 or 500 ppm had lower serum Zn and higher serum Cu concentrations than sows fed 5,000 ppm Zn at 10 and 14 mo of age. The number of pigs farrowed (total and live) and birth weight were not affected by dam's dietary treatment. However, sows receiving no additional Zn had a higher number of abnormal pigs/litter than sows on the other treatments. Sows fed 5,000 ppm additional Zn weaned fewer pigs that weighed less at weaning than sows on the other treatments. The concentration of Zn in the sow's liver increased significantly and liver Cu decreased as dietary level of Zn increased. Sows receiving 5,000 ppm Zn had lower hepatic Fe stores compared with sows receiving 500 ppm Zn. Elevated renal Cu and Zn concentrations were found in sows fed the highest level of Zn supplementation. The Zn concentration was higher and the Cu concentration lower in the aorta of sows fed 5,000 ppm Zn compared with sows fed 0 or 50 ppm additional Zn. Incidence of osteochondrosis was higher in sows supplemented with 5,000 ppm Zn than for sows from the other treatments. 相似文献
128.
129.
MA Balboa J Balsinde DA Dillon GM Carman EA Dennis 《Canadian Metallurgical Quarterly》1999,274(1):522-526
We have found that the novel phospholipid diacylglycerol pyrophosphate (DGPP), identified in bacteria, yeast, and plants, but not in mammalian cells, is able to potently activate macrophages for enhanced secretion of arachidonate metabolites, a key event in the immunoinflammatory response of leukocytes. Macrophage responses to DGPP are specific and are not mediated by its conversion into other putative lipid mediators such as phosphatidic acid, lysophosphatidic acid, or diacylglycerol. The responses to DGPP are compatible with a receptor-recognition event because they are blocked by suramin. Intracellular signaling initiated by DGPP includes phosphorylation and activation of the Group IV cytosolic phospholipase A2 and of the extracellular-signal regulated p42 mitogen-activated protein kinase (MAPK) and p44 MAPK, and membrane translocation of the protein kinase C isoenzymes alpha, epsilon, delta. These results establish DGPP as a novel macrophage-activating factor and suggest a potential role for this compound in triggering homeostatic cellular responses. 相似文献
130.
The phosphorylation state of three identified neural-specific protein kinase C substrates (RC3, GAP-43/B-50, and MARCKS) was monitored in hippocampal slices of mice lacking the gamma-subtype of protein kinase C and wild-type controls by quantitative immunoprecipitation following 32Pi labeling. Depolarization with potassium, activation of glutamate receptors with glutamate, or direct stimulation of protein kinase C with a phorbol ester increased RC3 phosphorylation in wild-type animals but failed to affect RC3 phosphorylation in mice lacking the gamma-subtype of protein kinase C. Our results suggests the following biochemical pathway: activation of a postsynaptic (metabotropic) glutamate receptor stimulates the gamma-subtype of protein kinase C, which in turn phosphorylates RC3. The inability to increase RC3 phosphorylation in mice lacking the gamma-subtype of protein kinase C by membrane depolarization or glutamate receptor activation may contribute to the spatial learning deficits and impaired hippocampal LTP observed in these mice. 相似文献