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951.
Differential diagnosis of poisoning by North American mushrooms, with particular emphasis on Amanita phalloides-like intoxication 总被引:2,自引:0,他引:2
It is possible to determine the management and prognosis of mushroom poisoning from the history and initial symptoms with a high degree of confidence. The most important intoxications are those involving Amanita phalloides or other potentially fatal amatoxin-containing mushrooms, which have a latent period of ten to 12 hours before the patient becomes symptomatic. Because aggressive gastroenteric decontamination can reduce the extent of hepatic damage, it is important to attempt to determine during this asymptomatic period whether amatoxin exposure has occurred. Various laboratory methods that might be useful are reviewed. 相似文献
952.
G H Ballantyne M J Zdon D E Schafer G R Fratesi J R Roberts M Tyshkov I M Modlin 《Annals of surgery》1986,204(5):559-565
The cellular mechanisms by which pepsinogen (PNG) secretion is controlled are not understood. The aim of this study was to explore whether modulation of PNG secretion is mediated by cAMP or calcium-calmodulin (C-C). PNG secretion in isolated rabbit gastric fundic glands (IGG) was tested, using agents believed to act via cAMP or C-C. IGG were stimulated for 30 minutes with histamine (H) 10(-5) M, isoproterenol (I) 10(-5) M, carbachol (C) 10(-5) M, cholecystokinin-octapeptide (CCK-8) 10(-7) M, forskolin (F) 10(-5) M, 8 bromo-cAMP (8B) 10(-3) M, and A23187 (A) 10(-6) M. PNG levels were determined by spectrophotometric assay of hemoglobin digestion products. PNG amounts secreted were (mean per cent above basal levels of total IGG PNG units +/- SEM): H, -0.02 +/- 0.30%; I, 3.5 +/- 0.9%; C, 5.1 +/- 2.2%; CCK-8, 5.3 +/- 1.5%; F, 10.6 +/- 3.8%; 8B, 13.8 +/- 4.5%; A, 2.1 +/- 1.1%. All secretagogues except H stimulated PNG release significantly above basal levels (p less than 0.05). A primary histaminergic mechanism for pepsinogen secretion is unlikely. Since two other adenylate cyclase activators, isoproterenol and forskolin and the 3':5'-cyclic adenosine monophosphate analog 8-bromo cAMP stimulated pepsinogen secretion, cAMP-dependence is probable. Since carbachol, CCK-8, and A23187, which are believed to act via calcium-calmodulin, also stimulated pepsinogen secretion, this system, too, presumably plays a substantial role. Thus the data support a dual 3':5'-cyclic adenosine monophosphate/calcium-calmodulin modulation of pepsinogen secretion. 相似文献
953.
954.
Using the buttock flap in 29 white Yorkshire pigs, blood flow and O2 consumption were measured at dermal temperatures between 35 degrees C and 15 degrees C. Flow was measured with an electromagnetic flowmeter and O2 consumption was calculated as the product of blood flow and the difference in flap A-VO2. Baseline flow was 6.6 +/- .9 (SE) ml/100 g/min at 35 degrees C and 3.1 +/- .02 (SE) ml/10 g/min at 15 degrees C. Blood flow through the flap stopped completely at a dermal temperature of 14 degrees C. Oxygen consumption was 0.16 +/- .02 (SE) ml/100 g/min at 35 degrees C and 0.04 +/- 0.01 (SE) ml/100 g/min at 15 degrees C. At 20 degrees C blood flow was 4.3 ml/100 g/min and metabolism was .04 ml/100 g/min. In other words, blood flow was 65% of baseline, while O2 consumption was only 25% of baseline. The therapeutic effect of local cooling at 20 degrees C deserves further investigation. The cessation of flow at 14 degrees C may be caused by increased plasma viscosity. 相似文献
955.
956.
Clinical experience of phototherapy for non-haemolytic hyperbilirubinaemia in 3999 infants in Kandang Kerbau Hospital, Singapore, is documented. Phototherapy was most effective in extremely preterm infants with very low birth weight (gestation less than or equal to 32 weeks, birth weight less than or equal to 1500 g) and least effective in full term infants with very low birth weight (gestation greater than or equal to 37 weeks, birth weight less than or equal to 1500 g) and large preterm infants (gestation less than 37 weeks, birth weight greater than 2270 g). Overall, phototherapy was effective in almost all the infants, with a failure rate of only 2.00/1000 infants. No characteristic features common to all the failures could be detected. The bilirubin rebound was usually mild; repeat phototherapy was required in only 30 infants (7.50/1000), with the response to the second exposure comparable to that to the first. No infant required a third exposure. All the infants tolerated phototherapy well, none developing any illness that could be attributed to the treatment. This clinical experience shows that phototherapy for the treatment of nonhaemolytic hyperbilirubinaemia is effective and safe. 相似文献
957.
V K Ryzhkov N A Borisova E M Gapchenko I A Dmitrieva 《Vestnik khirurgii imeni I. I. Grekova》1986,136(1):11-14
Roentgen endovascular occlusion with spiral emboli was used in 240 patients with different diseases. The introduction of spiral emboli into the arteries of abdominal and retroperitoneal organs was fulfilled through usual angiographic catheters. Duration of the arterial occlusion was checked up in the following angiographic examinations and showed the devices described to be appropriate for a continuous arterial blockade. No complications resulting from the introduction of the spiral embolus were noted. 相似文献
958.
H Hultgren P Peduzzi W Shapiro D van Heeckeren 《Progress in cardiovascular diseases》1986,28(4):279-284
959.
H J Keene 《Journal of dental research》1986,65(6):935-938
We examined the skeletal remains of 1338 early Hawaiians (preserved in the Bishop Museum, Honolulu) to determine total caries and root surface caries prevalence. Specimens from seven islands were represented in the collection. Estimation of age at death was made by a combination of dental developmental staging for younger individuals and occlusal attrition and/or alveolar bone loss in adults. Museum records were also consulted for age estimation of adults which was primarily based on osteological criteria. The material was divided into six age groups. Predentate infants and edentulous adults were not included. A total of 19,425 teeth was examined. Caries lesions were observed in 462 individuals (34.5%) and 1895 teeth (9.8%). Coronal caries lesions in children and adolescents tended to be small and not particularly destructive of tooth structure. Root surface lesions in young adults were also small but increased progressively in size in the older groups, resulting in pulp exposure and coronal amputation. Although coronal caries was apparently not a significant dental health problem in children and young adults (compared with contemporary Hawaiians), root surface caries was an increasingly important source of tooth morbidity and tooth mortality in the older population groups. This age-related caries pattern was similar for all of the islands. 相似文献
960.
The effects of platelet-activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) on phospholipase activity were studied in aortic smooth muscle cells and renal epithelial cells. When platelet-activating factor was added to cells prelabeled with [3H]arachidonic acid, it induced rapid hydrolysis of phospholipids. Up to 28% of incorporated [3H]arachidonic acid was released into the medium from both aortic and renal cells. A transient rise of diacylglycerol was also seen after the addition of platelet-activating factor to these cells. The accumulation of diacylglycerol and monoacylglycerol was relatively small when compared with the total amount of released free arachidonic acid. The amount of [3H]arachidonic acid released was comparable to the loss of phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine, which indicates that platelet-activating factor stimulates phospholipase A2 and C activity in aortic smooth muscle cells and renal epithelial cells. Platelet-activating factor also enhanced prostaglandin biosynthesis in these cells. 相似文献