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991.
Functional characteristics of intraepithelial lymphocytes from mouse small intestine. III. Inability of intraepithelial lymphocytes to induce a systemic graft-versus-host reaction is because of failure to migrate in vivo.
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In this study we have investigated whether addition of bone marrow accessory cells or concurrent administration of recombinant IL-2 would allow intraepithelial lymphocytes (IEL) to induce a systemic, lethal GvHR in irradiated hosts. In addition we have studied the ability of IEL to migrate into lymphoid tissues after intravenous injection and compared this with their locomotor capacity in vitro. 相似文献
992.
Congenital esophageal cysts in adults 总被引:1,自引:0,他引:1
Sixteen adult patients with congenital esophageal cysts were operated on between 1957 and 1979. Preoperatively, 7 patients (44%) were asymptomatic and the cyst was found incidentally on a routine chest roentgenogram. Esophageal symptoms were present in only 3 patients (19%), whereas most symptomatic patients had precordial sensations or arrhythmias. A correct preoperative diagnosis was made in only 1 patient. After enucleation of the cyst, preoperative symptoms were alleviated in all patients and short-term results were excellent. However, long-term follow-up 13.2 +/- 5.6 (+/- standard deviation) years later revealed moderate reflux in 9 (64%) of the surviving 14 patients. During esophagoscopy, macroscopic esophagitis was found in 12 (92%) of 13 patients. On histological examination of specimens obtained by forceps biopsy, esophagitis was present in 10 (77%) of 13 patients and included Barrett esophagus in 2. We conclude that, despite excellent early results, long-term follow-up of patients who undergo operation for congenital esophageal cysts is indicated because of the increased incidence of reflux esophagitis. 相似文献
993.
994.
The work gives substantiation of using complete intestinal lavage for certain indications in the complex treatment of incompetent colonic anastomoses. The method was efficiently used in 6 patients. 相似文献
995.
996.
D J Chambers M V Braimbridge D J Hearse 《European journal of cardio-thoracic surgery》1987,1(2):80-90
The isolated perfused working rat heart model of cardiopulmonary bypass was used to assess whether (a) allopurinol pretreatment enhances resistance to normothermic (30 min) or hypothermic (4 h) ischemia; (b) addition of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) to cardioplegic and/or reperfusion solutions are protective; (c) any protective effects are additive. With normothermic ischemia, allopurinol pretreatment improved recovery of aortic flow from its control value of 25 +/- 3% to 48 +/- 6% (P less than 0.05). Similarly, SOD plus CAT used during both ischemia and reperfusion improved recovery of aortic flow from a control value of 28 +/- 4% to 48 +/- 6% (P less than 0.05). However, various combinations of the two types of intervention afforded no additive protection. Under hypothermic (21 degrees C) conditions, allopurinol pretreatment was not effective, whereas SOD and CAT added during ischemia and reperfusion improved recovery of aortic flow from its control value of 53 +/- 4% to 69 +/- 5% (P less than 0.05). This value was similar to allopurinol pretreatment and SOD plus CAT added during ischemia and reperfusion (69 +/- 6%: P less than 0.05). These results provide further evidence that reperfusion-induced free radical formation may adversely affect postischemic recovery of function. The absence of an additive effect suggests a common mechanism of action, which is likely to involve the free radical-generating enzyme xanthine oxidase; however, other mechanisms may exist. Our results further support the use of antifree radical intervention in conjunction with cardioplegia to protect the heart during ischemia and reperfusion. 相似文献
997.
998.
A patient with keratoconus suffered two traumatic ruptures of her corneal graft wound, both of which were successfully repaired with restoration of graft clarity. There were also two apparently unrelated episodes of rejection. The endothelium was monitored by specular microscopy during this period. Our findings suggest that the insult to a transplanted cornea from an episode of rejection may be greater than that from traumatic wound rupture. 相似文献
999.
The aim of the study was to determine the effect of exogenous melatonin treatment on circulating prolactin levels in red deer. Melatonin was administered from 12 June 1984 (day 1) to lactating and non-lactating hinds in the feed daily at 1600 h, and to non-lactating hinds by a subcutaneous implant. Average concentrations (ng/ml) of prolactin in plasma taken serially over 15-h periods were significantly higher for untreated hinds than for melatonin-treated animals on day 15 whether lactating (66-133 v. 23-28, P less than 0.05) or non-lactating (28-174 v. 8-13, P less than 0.01), remained higher on day 36 (lactating: 41-152 v. 15-21, P less than 0.05; non-lactating: 21-50 v. 1-7, P less than 0.001) but had decreased to similar levels on day 72 (lactating: 5-24 v. 7-17; non-lactating: 2-9 v. 0-4). The advanced reduction in plasma prolactin for all melatonin-treated hinds was associated with an advanced onset of seasonal breeding activity. 相似文献
1000.
A A Jackson A V Badaloo T Forrester J M Hibbert C Persaud 《The British journal of nutrition》1987,58(2):207-214
1. The evidence is accumulating to suggest that glycine, the simplest amino acid, is conditionally essential in man. Benzoic acid, by conjugation with glycine to form hippuric acid, is known to deplete the free glycine pool of the body. Glycine is one substrate for the enzyme glutathione synthase (EC 6.3.2.3) and in the inborn error of metabolism in which glutathione synthase function is defective, increased quantities of 5-oxoproline are excreted in the urine. 2. An oral dose of 4-10 g sodium benzoate was given to six normal adults to deplete the metabolic pool of glycine, and the urinary excretion of 5-oxoproline was followed for 6 h. In five of the six, a significant increase in the urinary 5-oxoproline was seen within 3 h. 3. These findings show that 5-oxoprolinuria can result from limited glycine availability, and may provide a useful test for assessing glycine sufficiency in a range of physiological and pathological states. 相似文献