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21.
Immunological interferences between kidney and pancreas transplants were investigated in a genetically defined rat model of combined kidney and pancreas transplantation. Kidney and whole-pancreas grafts were transplanted microsurgically either as individual grafts or in a combined technique. Whole pancreas grafts were grafted into streptozotocin diabetic recipients (55 mg/kg bodyweight i.v.) three days after induction of diabetes. The exocrine secretion was suppressed by duct ligation. Rejection of the grafts was defined by recurrence of diabetes in pancreas-grafted recipients and renal failure after kidney transplantation. There were marked differences in the efficacy of identical short-term cyclosporine immunosuppression (15 mg/kg intramuscularly for 14 days): DA kidneys survived indefinitely in LEW rats (MST greater than 100 days), while DA pancreas allografts underwent prolonged but not permanent survival (P less than 0.01) either as individual grafts (MST 27.3 +/- 1,9 days) or when transplanted simultaneously together with the kidney (44 +/- 16 days) (P less than 0.01). LEW rats carrying a DA kidney for 100 days also rejected a subsequent donor-specific pancreas transplant within 30 days. The histological alterations in the kidney were more pronounced than after cyclosporine-induced DA kidney long-term survival alone. By contrast to the rejecting subsequently transferred pancreas, a metachronous second DA kidney was permanently accepted (greater than 100 days) without further immunosuppression after removal of the first graft, while unrelated LEW. 1U kidneys were acutely rejected. In summary, the results indicate that there are not only quantitative differences of kidney and pancreas allograft survival but also differences concerning the state of immunological unresponsiveness induced by identical cyclosporine immunosuppression. While CsA induces donor-specific immunological unresponsiveness after kidney transplantation, pancreas transplants are all eventually rejected after some differential prolongation of survival. Further investigations on the effects of different MHC and minor alloantigens may provide more insight into the complex immunological situation of individual and combined kidney and pancreas transplantation.  相似文献   
22.
Introduction Failure to enter the coronary sinus (CS) with a guiding catheter and entering its tributaries remains challenging in left ventricle (LV) pacing lead implants for cardiac resynchronization therapy (CRT). A dual telescoping catheter system (8F outer/6F inner) is designed to provide the ability to adjust the catheter curve size, shape and/or reach to the patients’ anatomy avoiding the need for catheter change. Methods Five different designs for CS cannulation were randomly tested in 64 patients scheduled for CRT device implant. Results In 33 consecutive patients three adaptable telescoping guiding catheter systems were tested per patient, the adaptable catheters had higher overall cannulation success rates (68, 63 and 62%) compared to the fixed shape catheter (46%) and an greater cannulation success rate when the CS location was not known (70, 53 and 72% vs 33% for the fixed shape). In a second group of 31 CRT patients the two telescoping catheters had similar high levels of success (71–80%), with or without using the inner catheter. Conclusions The telescopic system is adaptable to a wide range of anatomical variations in patients and can result in a higher CS cannulation success rate due to its adjustability in the RA in search for the CS ostium. On top of this the inner catheter allows for sub-selecting the CS tributaries.  相似文献   
23.
The success of modern burn therapy is based mainly on special burn intensive care, topical treatment, early eschar excision, and wound closure by immediate skin grafting or skin substitutes. This paper describes the current state of wound care and skin substitutes in burn therapy.  相似文献   
24.
Family physicians, regardless of training, board certification, or practice setting, more commonly consult or refer to internal medicine subspecialists than to general internists. The primary reason is need for a consultant with technical (procedural) skill. In the case of pediatric referrals, family physicians more commonly refer to general pediatricians than to pediatric subspecialists. Physicians who use pediatric subspecialists more when both are available, however, do so because of the need for a consultant with technical skill. Large numbers of internal medicine and pediatric residents are choosing subspecialties, thereby increasing availability of these subspecialties. At the same time, there is a documented need for an increased number of primary care physicians. Family physicians, general internists, and general pediatricians all need to be trained; however, because the breadth of training of the family physician prepares this practitioner to provide comprehensive primary care in a broad variety of settings, there should be an emphasis on training this specialist.  相似文献   
25.
The simian immunodeficiency virus is a retrovirus closely related to the human immunodeficiency viruses; it induces an AIDS-like disease in macaques, and provides therefore an obvious animal model for anti-lentiviral drug and vaccine strategy assessments. In our experiment, we immunized rhesus macaques with a purified and formalin-inactivated whole SIVmac251 antigen preparation. Most of these monkeys were still protected for more than 4 months following a heterologous SIVsm intravenous challenge. Both virus stocks, for vaccine preparation and challenge, were provided by culture supernatants of infected T cells of human origin. Four of the protected macaques were then reimmunized with the same antigen preparation and rechallenged intravenously with a homologous rhesus cell grown SIVmac251. Unexpectedly, all animals developed clinical and biological evidence of infection by day 15 after the second challenge.  相似文献   
26.
27.
Zusammenfassung Extrapyramidalen Störungen liegen zwar meist chronische Erkrankungen zugrunde, jedoch kommt es unter Umständen auch zum akuten Auftreten oder zu einer dramatischen Verschlechterung bis hin zu lebensbedrohlichen Zuständen. So kann ein Infekt, Medikamentenentzug oder eine Exikkose bei Parkinson-Patienten eine akinetische Krise auslösen. Auch akute, therapieassoziierte Psychosen mit Halluzinationen, Verwirrtheits- und Unruhezuständen können beim Parkinson-Patienten eine Notfallbehandlung erforderlich machen. Akute medikamenteninduzierte Dystonien treten nach einer Latenz von Stunden bis Tagen nach der Therapie mit Neuroleptika auf. Diese Frühdyskinesien können mit i.v.-Gabe von Anticholinergika effektiv behandelt werden. Seltene Folge einer Neuroleptikatherapie ist das maligne neuroleptische Syndrom, das mit Hyperthermie, Rigor und Bewusstseinsveränderungen einhergeht und zur kardiopulmonalen Dekompensation führen kann. Auch hier ist eine rasche Diagnosestellung entscheidend.  相似文献   
28.
Primary osteosarcoma of the liver   总被引:1,自引:0,他引:1  
Extraskeletal osteosarcomas are infrequent, and those that arise within parenchymal organs are very rare indeed. This case of a 71-year-old man with a primary osteosarcoma of the liver is the second reported in man. Pathologic findings, including ultrastructural features, at surgery and autopsy are presented. The differential diagnosis is discussed in detail.  相似文献   
29.
We describe a successful pregnancy in a 22-year-old patient with advanced renal failure, who gave birth to a living boy in the 35th week of pregnancy. At the time of spontaneous delivery the mother had a serum creatinine of 851 mol/l. No dialysis treatment had been instituted during this successful pregnancy.  相似文献   
30.
The effect of dextran sulfate on [3H]dThd incorporation in lymphoid cells was investigated. The polyanion activated DNA synthesis in spleen and bone marrow cells of normal mice. The highest rate of activation was detected in spleen cells of athymic (nude) mice; the ratio of [3H]dThd incorporation was higher in TxBM spleen cells of thymectomized, lethally irradiated and bone marrow protected mice than in spleen cells of normal donors. Thymus cells of normal mice could not be stimulated, but a slight response was obtained in cortisone-resistant thymus cells. A synergetic effect was found in normal thymus cells using a combination of dextran sulfate and phytohemagglutinin (PHA). In contrast, lipopolysaccharide and PHA showed no synergetic effect. The possible mode of action of polyanions as de-repressors of DNA synthesis is discussed.  相似文献   
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