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81.
82.
Loss M Kunz R Przemeck M Schmidtko J Arends H Jalali A Lorenz R Piepenbrock S Klempnauer J Winkler M 《Transplantation》2000,69(6):1155-1159
Organs transplanted between phylogenetically disparate species, such as from the pig into the primate, are subject to hyperacute rejection (HAR). This form of xenograft rejection is mediated by preformed natural antibodies and is believed to occur invariably in discordant xenografts thus leading to rapid destruction and complete thrombosis of the graft. Recent data, however, have shown that in the porcine to cynomolgus monkey setting, HAR is not inevitably seen after porcine kidney transplantation. The influence of preoperative antiporcine antibody levels in the recipient, cold ischemia time, and donor organ weight on the onset of HAR was investigated by using unmodified large white pigs (aged 3-12 weeks) as organ donors and adult cynomolgus monkeys (aged 1.5-3.5 years) as recipients. Porcine kidney xenotransplantation was performed in either a non-life-supporting model (n=7) or in a life-supporting model (n=8). In both models, no correlation was found between cold ischemia time and HAR. When preoperative anti-porcine antibody levels were investigated, a significant increase in incidence of HAR was observed in animals with elevated anti-porcine IgM (P<0.05) but not IgG levels (P=NS). Interestingly, although 5 of 12 grafts with an organ weight of less than 50 g underwent HAR, none of three grafts with a donor organ weight of more than 70 g showed signs of HAR. In addition, all three larger grafts showed intraoperative and postoperative urine production, although only in 1 (48 g) of the 12 grafts weighing less than 50 g primary graft function was observed. In one animal, a second porcine kidney (23 g) was successfully transplanted (without HAR) immediately after HAR and subsequent removal of a first porcine kidney (20 g). These results indicate that in the porcine to cynomolgus monkey setting anti-porcine IgM rather than IgG anti-porcine antibody levels seem to be of predominant importance for the induction of HAR. By increasing the donor organ size and weight the frequency of the onset of HAR can be at least reduced. This is most likely due to immunoabsorption of the recipients preformed antibodies in the porcine kidney without lethal damage for the graft. 相似文献
83.
Ulrike Heider Corinna Langelotz Christian Jakob Ivana Zavrski Claudia Fleissner Jan Eucker Kurt Possinger Lorenz C Hofbauer Orhan Sezer 《Clinical cancer research》2003,9(4):1436-1440
PURPOSE: Increased bone resorption is a hallmark of multiple myeloma and is attributable to osteoclast activation. Recent studies showed that the receptor activator of nuclear factor kappaB ligand (RANKL) is the key mediator of osteoclastogenesis and plays a crucial role in bone destruction in malignant bone disease. We found that human myeloma cells express RANKL and analyzed the association of the RANKL expression with the presence of osteolytic bone disease in patients with multiple myeloma. EXPERIMENTAL DESIGN: Flow cytometry was performed on bone marrow samples derived from controls and multiple myeloma patients with or without osteolytic bone lesions on conventional radiography. Plasma cells were identified as CD38++/CD138+ cells. The level of RANKL expression on the surface of bone marrow plasma cells was correlated with the bone status of the patients. RESULTS: The bone marrow plasma cells from controls showed no or only a weak surface expression of RANKL, and the median mean fluorescence index (MFI) was 6. In contrast, expression of RANKL could be detected on bone marrow plasma cells from all of the patients with multiple myeloma, and median MFI was 47. The difference in MFI for RANKL expression of bone marrow plasma cells from controls and myeloma patients was highly significant (P < 0.0005). Myeloma patients with osteolytic bone lesions showed a significantly higher expression of RANKL (median MFI = 60; range, 16-2494) compared with patients without osteolysis (median MFI = 16; range, 6-229; P < 0.0005). CONCLUSIONS: These results show for the first time that the level of RANKL expression by myeloma cells correlates significantly with osteolytic bone disease. 相似文献
84.
Zum Thema
Etwa 1–2 % der Schwangeren müssen sich w?hrend der Schwangerschaft einem operativen Eingriff unter An?sthesiebedingungen unterziehen.
Eine sichere An?sthesie für diese Eingriffe verlangt eine sorgf?ltige Planung und enge Kooperation von An?sthesist, Operateur
und Geburtshelfer. Der Geburtshelfer wird oft bereits im Vorfeld gemeinsam mit dem behandelnden Chirurgen die Indikation für
einen chirurgischen Eingriff in der Schwangerschaft beraten. Dabei wird er meist nicht nur um eine pr?operative Beurteilung
gebeten, z. B. um die Notwendigkeit einer prophylaktischen Tokolyse zu erw?gen, sondern zunehmend auch in die perioperative
überwachung der Schwangerschaft eingebunden. 相似文献
85.
A 4-year-old boy presented with acute abdominal pain and a 1-year history of intermittent umbilical complaints. Ultrasonographic
examination demonstrated a large cyst in the lower abdomen divided by a thin membrane. With micturition, impaired bladder
function was expected. Initial suprapubic drainage produced 1,000 ml dark-brown liquid. Laparotomy revealed an ileal duplication
cyst. Preoperative computed tomography and laparoscopy with the cyst drained did not further clarify the diagnosis.
Accepted: 5 August 1997 相似文献
86.
A CT-based method of marking superficial intracranial lesions with a needle is presented. This form of neuronavigation can be applied in every neurosurgical centre. Owing to its rapid application it is also suitable for cases of emergency. The neurosurgical approach can be centred precisely over the lesion providing for a minimally invasive operation. The method has proved its efficacy in numerous cases of haematomas and cystic lesions. 相似文献
87.
Chlorpromazine modulates cytokine expression in the liver and lung after burn injury and endotoxemia
Clancy KD Lorenz K Dries D Gamelli RL Hahn EL 《The Journal of trauma》2000,48(2):215-22; discussion 222-3
88.
89.
Fractures of the greater and lesser tuberosities of the humerus are often caused by direct trauma or traumatic dislocations. Besides clinical examination and radiological diagnostics, computed tomography (CT) scans and magnetic resonance imaging (MRI) should be obtained. In general, fragment dislocations up to 3?mm are treated non-operatively with repeated radiological control examinations. Operative treatment includes osteosynthesis with plates, screws or suture fixation. This article describes the procedure including arthroscopy and fixation by suture anchors. This technique has several advantages: (1) The tuberosities can be securely fixed even when they are split into several pieces, (2) there is no need for hardware removal in a second procedure, (3) continuous and planar fixation of the fragment to the bone, (4) primary stability allows early functional rehabilitation. 相似文献
90.
Andrea Lorenz Otto Müller Philipp Kohler Markus Wünschel Nikolaus Wülker Ulf G. Leichtle 《The Knee》2012,19(6):818-822
BackgroundIn patients with anterior knee pain and patellar instability, a specific training of the quadriceps muscle – especially the vastus medialis – is often recommended, although the practicability is discussed controversially and the proof of a measurable clinical effect is difficult. Therefore, this in vitro study investigates the influence of asymmetric muscle loading on the motion of the human patella.MethodsSeven human knee specimens were tested in a specially developed knee simulator. During simulated weight-bearing knee flexion, the kinematics of tibia, femur and patella were measured using an ultrasound motion capture system. The quadriceps forces were controlled to achieve a constant ankle force over the whole flexion range which is assumed to represent almost physiological loading. Three different force distributions of the quadriceps were tested — a central, equally distributed load as well as mainly lateral and medial loads.ResultsA significant influence of different quadriceps force distributions was found for patellar tilt around a proximodistal axis (up to 1.7°) and patellar rotation around an anteroposterior axis (up to 3.8°) with respect to the femur. Interestingly, the patellar mediolateral shift was influenced only marginally (< 1.5 mm).ConclusionsSpecific muscle training might help patients with patellofemoral pain and cartilage damage by a slight modification of the kinematics, but we could show that even highly asymmetric quadriceps loads only led to a small alteration of the mediolateral shift in case of a physiologic anatomy of the trochlear groove. 相似文献