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91.
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Liver and intestine transplantation   总被引:1,自引:0,他引:1  
The most significant development in liver transplantation in the USA over the past year was the full implementation of the MELD- and PELD-based allocation policy in March 2002, which shifted emphasis from waiting time within broad medical urgency status to prioritization by risk of waiting list death. The implementation of this system has led to a decrease in pretransplant mortality without increasing post-transplant mortality, despite a higher severity of illness at the time of transplant.
The trend over the last few years of rapidly increasing numbers of adult living donor liver transplants was reversed in 2002 by a decline of more than 30% in the number of these procedures. In 2002, a greater percentage of women received livers from living donors (43%) than deceased donors (34%), possibly because of size considerations.
From 1993 to 2001, the waiting list increased more than sixfold, from 2902 patients to 18 047 patients. For the first time since 1993, the waiting list size decreased in 2002, dropping 6% to 16 974 candidates. The percentage of temporarily inactive liver candidates also increased from 2001, thus the net decrease in the active waiting list for 2002 was 12%. This may reflect a trend toward less pre-emptive listing practices under MELD.
Intestine transplantation remains a low-volume procedure limited to a few transplant centers and is still accompanied by significant pre- and post-transplantation risks. As this procedure matures, its application may increase to include recipients at an earlier stage of their disease with better likelihood of success.  相似文献   
94.
The risk of hemorrhage in infants with severe coagulopathies unresponsive to fresh frozen plasma (FFP) infusions may preclude therapeutic invasive interventional procedures. We describe the successful use of recombinant factor VIIa (rFVIIa) in two such infants, the first with cirrhosis requiring paracentesis and the second with necrotizing enterocolitis requiring laparotomy. This report reviews the current concepts on the mechanism of action of the drug rFVIIa and considers its expanded use in infants unresponsive to FFP replacement.  相似文献   
95.
Patients who have had ileogastrostomy for the treatment of morbid obesity require close, long-term follow-up. From a prospective study of a large number of variables in 12 consecutive patients, and from experience with more than 200 patients who have undergone this procedure since 1982, a protocol has evolved. The authors outline the associated morbid conditions, operative complications and biochemical alterations that are important in the management of these patients.  相似文献   
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Precipitate analysis from an indwelling total parenteral nutrition catheter   总被引:2,自引:0,他引:2  
The composition of a precipitate obtained from a silastic right atrial catheter was determined. The precipitate was collected and washed with deionized water thoroughly before subjecting portions of it to organic and inorganic analysis. Inorganic analysis was conducted using scanning electron microscopy and x-ray spectroscopy for sodium, aluminum, silicone, sulfur, chlorine, and calcium. Phosphorus analysis was conducted by a commercial laboratory. Organic analysis was conducted by thin layer chromatography with cholesterol, phosphatidyl serine, phosphatidyl choline, phosphatidyl ethanolamine, and sphingomyelin as standards. Silicone, calcium, and phosphorus and three organic compounds, which could not be conclusively identified, were found. The precipitate was most likely calcium phosphate intermixed with silicone oil lubricant and residual total parenteral nutrition (TPN) solution. This formed in the catheter at body temperature probably due to incomplete catheter flushing.  相似文献   
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The pattern of fluctuation in the population size of Bulinus globosus and Biomphalaria pfeifferi, in their infection rates with Schistosoma haematobium/S. mattheei and S. mansoni, respectively, and in the cercarial population size as monitored using hamster immersions, was elucidated in streams in the temperate highveld region of Zimbabwe over a 27-month period during 1982-1984. The results revealed that transmission of S. mansoni was erratic and unpredictable without a clearcut seasonal transmission pattern. In contrast, transmission of S. haematobium and S. mattheei exhibited a marked seasonal pattern, being most intensive during the hot, dry season (September-November) and markedly reduced during the cold, dry season (June-August). During the rainy (December-February) and warm, post-rainy (March-May) seasons transmission was moderate and variable, but occasionally intensive. The results also showed that rodent immersion is to be preferred to measurements of snail population size and snail infection rate in elucidating seasonality of transmission of schistosomiasis.  相似文献   
100.
Unscheduled DNA synthesis (UDS) was studied by quantitative autoradiography in human urothelial cells of three transformation grades (TGr I-III). Cells incubated in arginine-free medium supplemented with hydroxyurea showed dose-dependent UDS after administration of agents injurious to DNA, while the scheduled synthesis of DNA was nearly totally suppressed. UDS was demonstrated after treatment with the ultimate carcinogen N-methyl-N-nitroso-N'-nitroguanidine (CAS: 70-25-7) or with the procarcinogen 4-nitroquinoline-1-oxide (4-NQO; CAS: 56-57-5). In cultures treated with benzo[a]pyrene (CAS: 50-32-8), which requires a different activation system than that for 4-NQO, UDS was less pronounced. In 9 cell lines the average rates of UDS were inversely related to TGr. Two cell lines showed a different pattern.  相似文献   
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