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11.
To date, little is known about the duration and effectiveness of immunity as well as possible adverse late effects after an infection with SARS-CoV-2. Thus it is unclear, when and if liver transplantation can be safely offered to patients who suffered from COVID-19. Here, we report on a successful liver transplantation shortly after convalescence from COVID-19 with subsequent partial seroreversion as well as recurrence and prolonged shedding of viral RNA.  相似文献   
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BACKGROUND.: Although chronic hepatitis C infection is one of the factorsthat can lead to morbidity and mortality in renal allograftrecipients, treatment procedures have not been well documented.Interferon treatment has been shown to be effective in the normalizationof biochemical hepatitis C and in the clearing of hepatitisC virus RNA. However, little is known concerning the efficacyand safety of interferon treatment in renal allograft recipientswith chronic hepatitis C. Interferon has also been accused ofincreasing renal allograft rejection. METHODS.: Recombinant -interferon in a dose of 4.5 million units threetimes per week was given to five renal-allograft recipientswith chronic hepatitis C for 6 months. Besides biochemical investigations,liver histopathologies before and after the treatment coursewere also studied. RESULTS.: Interferon treatment was effective in two of the patients, inanother two cases renal function deteriorated during the treatment.In the last case ALT increased again after cessation of interferontherapy. CONCLUSION.: We conclude that interferon seems to be moderately effectivein treating chronic hepatitis C in renal allograft recipients,but a risk of renal functional deterioration and rejection remains.  相似文献   
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A previously undefined phenotype of CD8(+) cells that appears to represent in vivo activated CTL precursors (CTLP*) has been identified in the spleens of C57Bl/6 mice responding to a P815 tumor allograft. This population was first evident by the transient expression of very high levels of CD28 and CD44 on day 5 of the allograft response and reached maximal levels on days 7 and 8 before declining on day 9. A transient increase in CD69 expression was also observed on these cells on day 5. In contrast, CTL effectors (CTLE), identified by their CD8(+)CD44(hi)CD62LloCD45RBlo phenotype, were not appreciably detected in the spleen until day 8 and reached maximal levels on day 10. Further characterization of CTLP* on day 7 revealed that they represented blasting cells by increased light scatter and also expressed very high levels of CD54 but not CD122, CD152, or CD154. In addition, the cells had already up-regulated CD49d, asialo GM1, CD11a, and CD95L, and down-regulated their expression of CD62L. A small percentage of these cells also expressed CD25. Day 7 CTLP* sorted on the basis of their CD44(xhi) and CD54(xhi) phenotype did not exhibit cytolytic activity in a standard chromium release assay but became cytotoxic when they were cultured in the presence of exogenous murine IL-2 for 5 days. Granzyme B activity, however, was detected in CTLP* on day 7 at levels equivalent to CTLE on day 10. In order to establish a potential precursor relationship between CTLP* and CTLE, mice were treated with various doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a chemical that has been shown to dose-dependently suppress the in vivo generation of CTLE to P815 tumor cells by altering an early stage of CTLP activation. Results indicated that CTLP* were suppressed by TCDD on day 7 to the same degree that CTLE were suppressed on day 10. Importantly, for controls and for all doses of TCDD, there were approximately 12.5 CTLE on day 10 for every CTLP* detected on day 7. These results suggested that TCDD acted identically across all doses to inhibit the early stages of activation of CTLP but did not affect the final stages of differentiation and expansion to CTLE. This interpretation supports the previous observation that TCDD exposure had to occur within the first 3 days of the allograft response in order to induce suppression of CTLE activity. Taken together, these results support the conclusion that in vivo activated CTLP can be identified by their unique expression of very high levels of CD44, CD28, and/or CD54 prior to their full maturation and clonal expansion to functional CTLE.  相似文献   
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The abdominal left ventricular assist device (ALVAD) is an order of magnitude more effective than conventional intra-aortic balloon pumping (IABP) in unloading and providing circulatory support to the failing left ventricle. This is a report of a unique case which demonstrates that in the absence of pulmonary vascular obstruction or constriction, the ALVAD can substitute for both left and right heart function. A 21-year-old patient with a congenital bicuspid aortic valve developed acute valvular endocarditis which rapidly progressed to congestive heart failure. An operation was undertaken, the mitral and aortic valves were excised and replaced by porcine heterografts, and a fistula from the right sinus of Valsalva to the right ventricle was closed. When coronary circulation was restored, irreversible ischemic contracture of the left ventricle, or "stone heart" syndrome, developed and emergency ALVAD or partial artificial heart implantation was effected. This device functioned as a total artificial heart for nearly six days, while a donor heart was sought. The patient then underwent removal of the ALVAD and cardiac and renal allografting. The transplanted heart functioned well, but the patient expired fifteen days later from gram-negative sepsis.  相似文献   
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Objective: To determine the perfusion territories of the superior and inferior thyroid arteries in humans. Tracheal transplantation is a potential option for management of long-segment tracheal stenosis. However, the maximum length of vascularized trachea that can be reliably transplanted has not been established. Study Design: The tracheal vascular territory of individual superior and inferior thyroid arteries was determined separately in 10 humans postmortem. Methods: India ink was infused unilaterally under controlled pressure into the superior (n = 5) and inferior (n = 5) thyroid arteries of cadaveric tracheas. Tracheas were sectioned longitudinally and the caudalmost extent of mucosal dye staining was determined via microscopic assessment. Results: The tracheal perfusion territory of the superior thyroid artery was two to five rings (1.7 ± 0.5 cm) and the inferior thyroid artery, nine to 13 rings (6.5 ± 1.1 cm). In both cases, the tracheal mucosa on the contralateral side was stained to the same caudal level. Conclusions: The inferior thyroid artery was shown to perfuse the trachea maximally to the 13th ring (8.1 cm). As such, the unilateral inferior thyroid artery would serve as a suitable vascular component for long-segment tracheal transplantation in humans.  相似文献   
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Summary Cytomegalovirus (CMV) encephalitis, characterized by microglial nodules, is a major neurological complication in AIDS. There is a clear need for a well-characterized laboratory model of CMV encephalitis. We report here the sequential virological, histopathological, and antibody responses of young guinea pigs inoculated intracerebrally with guinea pig CMV. Virus was found to peak in the brain in the 1st week, to peak in the spleen in the 2nd week, and to be cleared from the brain with the development of serum neutralizing antibody 3 to 4 weeks post infection. Leptomeningitis peaked at the end of the 1st week, independent of the changes found in the parenchyma. Diffuse and focal infiltration of systemic cells was found in the cortex. Microglial nodules consisting of swirled and elongated cells, sometimes in association with intranuclear inclusion bearing cells, were prominent. The parenchymal changes, including scattered foci of ependymitis and ventriculitis, were most prominent in the 2nd week post infection. This model should facilitate studies of the host defense response in the brain and of the role of antiviral therapy in CMV encephalitis.Supported by funds from the Medical Research Service of the Veterans Administration  相似文献   
19.
Abstract

Objective. Intestinal and multivisceral transplantation have gained acceptance as treatment modalities for patients with: intestinal failure and life-threatening complications of parenteral nutrition (PN), rare cases of vascular abdominal catastrophes and selected cases of low-grade neoplastic tumors such as neuroendocrine pancreatic tumors and desmoids involving the mesenteric root. The aim was to describe the survival and nutritional outcome in the transplanted Nordic patients and the complications attributed to this procedure. Method. The authors included all Nordic patients transplanted between January 1998 and December 2013. Information on patients transplanted outside the Nordic region was collected through questionnaires. Results. A total of 34 patients received different types of intestinal allografts. Currently, there are two Nordic transplant centers (n = 29) performing these procedures (Gothenburg, Sweden n = 24, Helsinki, Finland n = 5). The remaining five patients were transplanted in the USA (n = 3) and the UK (n = 2). Most patients were transplanted for life-threatening failure of PN (70%) caused primarily by intestinal motility diseases (59%). Allograft rejection was the most common complication and occurred in 79% of the patients followed by post-transplantation lymphoproliferative disorders (21%) and graft-versus-host disease (18%). The 1- and 5-year survival was 79% and 65% respectively for the whole cohort and nutritional autonomy was achieved in 73% of the adults and 57% of the children at 1 year after transplantation. Conclusion. This collective Nordic experience confirms that intestinal transplantation is a complex procedure with many complications, yet with the possibility to provide long-term survival in selected conditions previously considered untreatable.  相似文献   
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异体骨关节移植后骨愈合的X线形式及影响因素   总被引:6,自引:1,他引:6  
目的探讨肢体恶性肿瘤接受大段同种异体骨关节移植后和异体骨愈合在X线的表现及影响因素,以改进手术方法。方法1992年5月~1999年3月,对收治的90例中可纳入统计的85例骨恶性肿瘤在手术切除长段骨关节后,应用不同内固定方式进行异体骨关节移植,其中16例保留髁部关节面的异体骨段移植,57例异体关节移植,9例复合异体骨段人工髋关节置换,3例膝关节置换。术后平均随访2年9个月,以X线片表现判定骨愈合方式,依据Enneking肢体恶性肿瘤保肢术后的肢体功能标准,评价手术结果。结果85例101处异体骨与自体骨接合部有91处达到临床骨愈合。根据X线片表现特征,异体骨与自体骨间有4种愈合方式,其中以断端周围形成外骨痴、同时植骨间隙逐渐消失最多见;内固定不牢固是引起术后骨不愈合的主要原因;异体骨周围软组织覆盖、血供差及大段异体骨移植后诱发的免疫排异反应等可能影响骨愈合;远离异体骨与自体骨结合部的肿瘤复发或感染、不同长度的异体骨对骨愈合无肯定的负作用;选用牢固的髓内固定、断端周围植骨及采用骨膜袖套技术可减少术后骨不愈合的发生。结论大段异体骨关节移植后骨愈合有不同的X线片表现形式。手术设计应为异体骨提供充足的血液供应、牢固的内固定支撑和完善的软组织覆盖。  相似文献   
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