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991.
Non-operative management of malignant intestinal obstruction   总被引:1,自引:0,他引:1  
Intestinal obstruction is a relatively common clinical problem in patients with advanced cancer, particularly those with colorectal and ovarian tumours. A proportion of patients have a non-malignant cause for their obstruction, but in the remaining patients obstruction will be caused by advanced malignancy itself. In the past, most patients were either managed surgically or by nasogastric intestinal decompression and intravenous hydration. Surgery in patients with advanced cancer is associated with high mortality and morbidity. Effective surgical decompression is difficult. We have managed 24 patients with advanced abdominal malignancy and previous operative or radiological evidence of intestinal obstruction without operation. The technique is only appropriate for patients in whom a solitary or correctable obstructing lesion can be excluded. The patient is encouraged to take free fluid and a diet low in fibre. Intestinal colic is managed with morphine, the dose required being titrated for each individual patient against background pain and colic. Vomiting is controlled by the parenteral administration of antiemetic drugs. To simplify drug administration, morphine and metoclopramide are mixed in the same syringe and infused subcutaneously simultaneously. In our 24 patients the mean survival rate after the onset of complete obstruction was 29.2 days. The mean dose of morphine infused was 9.2 mg/h, and the mean dose of metoclopramide was 6.9 mg/h. The case of an 82-year-old male patient is presented. We commend the technique to surgeons contemplating surgery in these very difficult patients. It is simple, relatively non-invasive and saves the patients the pain, discomfort and complications of unproductive surgery.  相似文献   
992.
Six Engstr?m Elsa anaesthetic machines have been in regular use for 18-24 months. The machine incorporates a number of new concepts for anaesthetic delivery and monitoring. At flows below 1000 ml/minute, each machine delivered 20% more than the indicated value; at higher flows, the indicated value was within 10% of the flow delivered. Minute volume, tidal volumes and oxygen concentrations were within the manufacturer's specifications. However, vaporizer and vapour monitor performance was outside the (SD) 5% accuracy claimed by the manufacturers. It was noted that the bistable valve requires user familiarity for the change from controlled to spontaneous ventilation to be accomplished with ease. It was also possible to misconnect the breathing system and so isolate the excess pressure escape valve and high-pressure alarm. Nevertheless, once familiarisation was achieved, the machines have proved easy to operate and are particularly satisfactory when used with low fresh gas flows.  相似文献   
993.
Cyclosporine A inhibition of microcystin toxins   总被引:2,自引:0,他引:2  
Cyclosporine A (CyA) given i.v. at a dose of 1.25 mg/mouse blocks a subsequent i.v. lethal dose (1.7-1.8 x LD50) of microcystin-LR for 24 hr, and is about 50% protective at 48 hr. Conversely, the fraction of mice that can be rescued by CyA (0.2 mg/mouse) after a lethal dose of microcystin-LR decreases rapidly with a pharmacodynamic half-time of only about 100 sec. The prophylactic action of CyA was tested against lethal doses of four microcystins. The acute lethality of 1.7-1.8 x LD50 dose of microcystin-LR, -RR, -LY, or -LA given 1 hr after administration of 0.2 mg of CyA is 0%, 0%, 58%, or 100%, respectively. Even a 0.6 mg/mouse dose of CyA is ineffective prophylaxis against a lethal dose of microcystin-LA. The inhibitory potency of CyA on microcystin toxicity can be completely reversed by the single L-amino acid substitution of alanine for arginine in the microcystin.  相似文献   
994.
Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed.  相似文献   
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Thrombosis of the vena cava, femoral veins or iliac veins can result in the formation of large collateral veins in the pelvis and retroperitoneum which are often asymptomatic but which may cause severe bleeding and produce major difficulties in urological management. Such abnormalities are a rare cause of urological symptoms but may be difficult to diagnose unless a high index of suspicion is maintained. Three patients are reported who developed significant urological problems as a consequence of acquired venous disease; the use of ultrasound, venography and CT in the diagnosis of this condition is described.  相似文献   
999.
A rat model of chronic serum sickness was used to study the pathogenesis of progressive glomerulosclerosis complicating experimental immune-complex glomerulonephritis. Chronic serum sickness was induced by immunising rats with bovine serum albumin followed by intraperitoneal administration of the antigen. Early lesions consisted of mesangial deposits of rat immunoglobulins, followed later by transient subendothelial and persistent subepithelial immune aggregates. On the basis of the peak level of proteinuria around day 80, three groups of rats were distinguished: I physiological proteinuria; II 50-500 mg/24 h; and III greater than 500 mg/24 h. The animals were killed at day 220 and the presence of mesangial proliferation, epithelial proliferation, and synechiae, as well as focal glomerulosclerosis was scored. It appeared that all and only proteinuric animals developed progressive glomerulosclerosis, although all three groups of animals passed through a phase with mesangial and subendothelial immune deposits. A strong correlation was found between the degree of proteinuria and the proportion of glomeruli affected. We conclude that the combination of mesangial and subendothelial deposits on the one hand and subepithelial deposits associated with increased protein loss on the other constitute a conditio sine qua non for the development of progressive glomerulosclerosis in this model. The use of specific antibodies to investigate the composition of the sclerotic lesions showed the presence of laminin and type IV collagen, but not of types I and III collagen in sclerotic areas of glomeruli. This indicates that the development of progressive glomerulosclerosis in this model is due to an increased production of glomerular basement membrane components by presumably solely glomerular cells after the occurrence of immunological glomerular injury.  相似文献   
1000.
The laryngeal mask in failed intubation   总被引:1,自引:0,他引:1  
  相似文献   
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