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61.
Spontaneous allograft rupture after kidney transplantation is a rare complication usually due to an acute rejection of the interstitial type. In a 32-year-old man kidney transplantation was performed under immunosuppression with prednisolone and ciclosporin (CS). The dose of CS was 5 mg/kg body weight intravenously for the first 24 h, on the 2nd day 10 mg/kg/day orally, with gradually decreasing doses thereafter. The patient remained oliguric in the postoperative period and received additionally 600 ml mannitol solution intravenously for osmodiuresis within a period of 6 days. On the 8th postoperative day, 48 h after the last intravenous infusion of mannitol, spontaneous renal rupture occurred. The CS concentrations in the blood during the days before the rupture were within the upper normal range for effective immunosuppression (300-600 ng/ml). Intraoperatively the kidney appeared enlarged due to edematous swelling of the graft, but it showed no signs of rejection. The histological finding was a toxic tubulopathy with extensive isometric vacuolization and peritubular congestion, a known side effect of both of CS and of mannitol. The rupture was successfully repaired. Thirty-four days after the transplantation diuresis increased and hemodialysis therapy could be discontinued. In a second biopsy of the kidney the signs of toxic tubulopathy with isometric vacuolization were reduced. On the following days the serum creatinine dropped below 160 mumol/l. It can be assumed that the combination of CS therapy and administration of massive and continued doses of mannitol in an oliguric patient with allograft kidney may potentiate severe tubulopathy with concomitant edematous swelling of the graft. This can result in an increasing danger of spontaneous renal rupture.  相似文献   
62.
The new thromboxane A2 antagonist [3H]BAY U 3405 was characterized for its binding to washed human platelets and platelet membranes. In washed platelets the specific binding was reversible, selective and stereospecific, but not saturable. The dissociation constant (Kd) was 6 +/- 2.5 nM, the number of specific binding sites 1177 +/- 306 per platelet. Three structurally different thromboxane A2 (TXA2)/prostaglandin H2 (prostaglandin endoperoxide) (PGH2) receptor ligands completely inhibited the specific binding of [3H]BAY U 3405 in a concentration-dependent manner, indicating that the observed high affinity binding site is the TXA2/PGH2 receptor. In platelet membranes, however, specific [3H]BAY U 3405 binding showed saturability in addition to reversibility, selectivity, and stereospecifity. The Kd of the binding was 9.6 +/- 2.3 nM in kinetic studies and 8.7 +/- 3.7 nM in saturation studies, the inhibition constant (Ki) was 10 +/- 1.1 nM in displacement studies. The TXA2/PGH2 receptor agonists U 46619 and CTA2, and the antagonists Daltroban (BM 13505), I-PTA-OH and SQ 29548 all completely inhibited the specific binding of [3H]BAY U 3405 thus defining the observed binding site as the TXA2/PGH2 receptor. In conclusion, the data suggest that the previously reported TXA2 antagonism of BAY U 3405 is mediated by binding to a specific high affinity binding site of human platelets and platelet membranes that represents the TXA2/PGH2 receptor.  相似文献   
63.
The epidemiology of sudden death, the etiology of inflight sudden incapacitation, and the influence of pilot age and experience on air accident rates are reviewed in order to determine the aeromedical emphasis needed to minimize accidents. Sudden deaths in men over age 35 are nearly all due to coronary artery disease, whereas in those under 35 years they are mostly due to hypertrophic cardiomyopathy. The incidence of fatal accidents from human error is, however, far greater than that from physical illness. Since inexperienced pilots have a 2-3 times increased incidence of mishaps due to pilot error, the estimated risk of disease related in-flight sudden incapacitation should be balanced by consideration of pilot experience. Therefore, it may be preferable to grant waivers to experienced pilots with an increased incidence of disease-related inflight sudden incapacitation than to replace them with novices. We conclude that overly strict medical criteria may paradoxically increase accident rates.  相似文献   
64.
Wilson's disease (WD) is an inherited disorder of copper metabolism yielding marked motor deficits, including a severely disabling tremor. As a structural correlate of the disease, a variety of cerebral abnormalities has been revealed. However, the relationship between motor deficits and cerebral lesions has remained largely unknown. Here, we investigated correlation between WD tremor and cerebral magnetic resonance imaging (MRI) findings. Cerebral MRI abnormalities in 6 symptomatic WD patients were compared to findings in 6 asymptomatic WD patients and 10 healthy controls. All patients were treated with long-term copper chelating therapy. Motor symptoms including tremor were determined by Unified Parkinson's Disease Rating Scale Part III (UPDRS-III). MRI findings in symptomatic WD patients revealed significant symmetric T2*-weighted hypointense signal alterations of globus pallidus, head of the caudate nucleus, and substantia nigra. In contrast, MRI of asymptomatic WD patients did not differ from healthy controls. Correlation analysis revealed a significant positive correlation between MRI basal ganglia lesions and UPDRS action tremor score. Our results demonstrate for the first time that Wilson's disease tremor is associated with lesions of the globus pallidus, the head of the caudate nucleus, and the substantia nigra.  相似文献   
65.
Abstract During treatment of femoral shaft fractures, not only the actual fracture reduction but also the retention of the achieved reduction is essential. Substantial forces may apply to the bone fragments, due to multidirectional muscular contraction. Furthermore, forces from manipulation of one bone fragment may be transferred over the soft tissues onto the other fragments, thus hindering accurate fracture reduction. Once a sufficient reduction has been achieved, this position must be retained whilst definitive internal fixation is performed. Conventional methods comprise mounting patients on a traction table and applying manual distraction or employing special distraction devices, such as the AO distractor device. These approaches, however, only insufficiently stabilize both main fragments. For example, on the traction table the proximal femoral fragment can pivot around the hip joint thus complicating precise reduction. A novel pneumatic stabilization device to assist surgeons during operative procedures is described. This passive holding device “Passhold” connects to one main fragment through a minimally invasive bone interface and statically locks the fragment’s position. Thereafter, only the other main fragment is manipulated to achieve reduction. Mutual interference of the reciprocal fragment positions, due to soft-tissue force transfer during manipulation, is avoided. The authors examined the stability of the novel retention device on a test rig and proved its functionality under sterile settings using cadaver tests. It is concluded that this device largely facilitates the operative procedure in femoral shaft fractures, is sufficiently stable and ergonomically suitable for intraoperative deployment.  相似文献   
66.
The effectiveness of interdisciplinary treatments for chronic pain is well established. In general, these treatments decrease psychosocial distress and increase physical abilities. Further, return to work rates following interdisciplinary treatment tend to be quite high. Previous studies have highlighted a number of factors that individually influence return to work rates; however, there is a need for more comprehensive and unified models that allow an evaluation of the inter-relations among these factors. The present investigation examined how demographic and treatment outcome variables interacted to influence post-treatment return to work rates in a sample of individuals with chronic pain following interdisciplinary treatment. Results indicated that patient age, lifting ability, pain duration, depression level, and reported disability were individually related to return to work; however, when these variables were evaluated relative to one another, level of depression and patient age had the best ability to predict post-treatment work status. These results add to the literature by specifically highlighting post-treatment factors that best discriminate patients who had returned to work from those that had not. Furthermore, they provide evidence that general emotional distress is perhaps the most important predictor of work status following treatment.  相似文献   
67.
68.
Zusammenfassung Auf Grund unserer vergleichenden Versuche empfehlen wir, neben der WaR. stets mehrere Trübungs- und Flockungsreaktionen auszuführen. Als recht brauchbar haben sich uns die Kahn-, Citochol- und Meinicke-Trübungs-Reaktion erwiesen, da sie schnell und leicht anzustellen und abzulesen und hinsichtlich Empfindlichkeit und Spezifität der WaR. gleichgestellt, in manchen Fällen sogar überlegen sind.  相似文献   
69.
Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm−5) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH2O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH2O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion.  相似文献   
70.
Nine cases of metal intraocular foreign body are presented. This study investigates the use of electrodiagnostic techniques in the diagnosis of metallosis and as a prognostic indicator. The electro-oculogram (EOG) and the electoretinogram (ERG) indicate that there are two mechanisms of metallosis, one of which involves cytotoxic damage by siderosomes, and the other lipid peroxidation of photoreceptor outer segments and retinal pigment epithelium. The evidence suggests that the location of the foreign body in the eye determines whether either or both of these mechanisms occur. We propose that these tests can help the ophthalmologist decide when a foreign body has to be removed and give information as to the mechanism of the pathological process.  相似文献   
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