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31.
The precise cause of allograft dysfunction after renal transplantation often cannot be established by non-invasive means. In clinical practice, radionuclide scans form an integral part of the clinician's armamentarium in the assessment of these patients [1, 2]. Unfortunately, in the clinical setting more than one pathological process may be responsible for the impaired function, making it difficult to correlate the scan appearances with the pathology. In this study in rats we compared the renal DTPA scan appearances of the various pathological processes which may cause renal allograft dysfunction in the immediate post-transplant period.  相似文献   
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Virgin female BALB/c mice were exposed in vivo to whole body gamma-radiation and/or to 7,12-dimethylbenz[a]anthracene (DMBA) p.o. Mammary epithelial cells were isolated and assayed for carcinogen altered cell populations both in vitro by an epithelial focus assay and in vivo by injection into cleared fat pads of syngeneic host mice. Five groups of mice were exposed as follows: (a) sham controls; (b) 50-rad gamma-radiation; (c) 100-rad gamma-radiation; (d) 75 micrograms DMBA; or (e) 50-rad gamma-radiation followed in 1 week by 75 micrograms DMBA. Mammary epithelial cells were isolated and assayed at 24 h and at 1, 4, 16, and 52 weeks after in vivo exposure. Four to 12 mice per treatment per time point were individually assayed. Altered in vitro growth potential was characterized by the proliferation of carcinogen exposed (but not control) cells as epithelial foci which persisted at least 12 weeks in primary culture. Epithelial foci which could then be subcultured at least four times were termed subculturable epithelial foci. Altered in vivo morphogenic potential was characterized by dysplastic or neoplastic growth in host fat pads. With increased time in situ between exposure and assay, cell populations emerged which exhibited both increased in vitro subculturability and enhanced tumorigenic potential including a host response upon injection in vivo. Further, combined radiation and DMBA resulted in higher frequencies of subculturable epithelial foci than either treatment alone. The relevance of these progressive cellular changes to the process of mammary tumor development is discussed.  相似文献   
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The pathogenesis of NC in VLBW infants appears to be multifactorial. The vulnerability of extreme immaturity and the underdevelopment of renal function may be the most important variables. In some ways, we view this problem as similar to that of retinopathy of prematurity. (Clearly the exposure of the retina to high partial pressures of oxygen contributes to the development of retinopathy of prematurity but other variables--some known, such as an immature retina, and others not yet defined--must be present.) Hypercalciuria is common in the VLBW infant, yet not all develop NC. Decreased glomerular filtration rate, low citrate excretion, and frequently an alkaline urine are in part due to the immaturity of renal function of these infants. The need for prolonged hyperalimentation resulting in increased oxalate excretion and the development of BPD frequently requiring diuretics that may cause phosphaturia and magnesium depletion and that may increase calcium excretion are more common in the smallest and sickest of premature infants. Even transient insults to the kidneys, such as hypoxia or hypotension or the use of nephrotoxic drugs that provoke tubular injury and cell death with the probability of crystal formation and growth by way of heterogeneous nucleation, are likely to occur more frequently in this vulnerable population.  相似文献   
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This study was undertaken to investigate the endocrine stress response during cataract surgery in local anaesthesia (LA) with or without additional sedation with midazolam (Dormicum). 20 patients for cataract surgery in LA were randomly allocated to the midazolam-group (before injection of LA, sedation with single doses of 1 mg midazolam until the patient was sleeping, but awakeable), and to the control-group without sedation. Premedication and LA were standardized. The investigation was performed at 7 measuring points starting at the arrival in the preparation room up to 30 min after surgery. Adrenaline in plasma was significantly lower in the midazolam-group. Intraoperatively, adrenaline increased in the control-group and decreased in the midazolam-group. In time course, noradrenaline in plasma decreased in the midazolam-group, in contrast to the control-group. With respect to ADH, ACTH and cortisol, no significant differences were found in group levels or time course, and concentrations remained within normal range. In contrast to the control-group, mean arterial pressure decreased in the midazolam-group during the course of time. There were no differences in heart rate or arterial oxygen saturation between the two groups. Local anaesthesia and premedication were sufficient to prevent psychic and surgical stressors. The slight sympathoadrenergic response in the control-group was significantly reduced by small doses of midazolam. Thus, a careful supplementation of local anaesthesia with midazolam appears advantageous for patients with cardiovascular disorders.  相似文献   
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OBJECTIVE: To improve smiling after long-term facial nerve palsy (FNP). Physiotherapy rehabilitation of an adapted (more symmetrical) smile was investigated in FNP subjects 1 year post-onset, using video self-modeling (video replay of only best adapted smiles) and implementation intentions (preplanning adapted smiles for specific situations). STUDY DESIGN AND SETTING: Prospective, blinded clinical trial. Facial-Nerve-Palsy Clinic. RESULTS: After video self-modeling: 1) reaction time (RT) to initiation of adapted smiles became 224 ms faster whereas RT for everyday (asymmetrical) smiles became 153 ms slower; 2) adapted smiles were completed 544 ms faster; 3) adapted smiles had higher overall quality, movement control, and symmetry ratings; and 4) Facial Disability Index scores also improved. Implementation intentions after video self-modeling ensured transfer of adapted smile to everyday situations. CONCLUSION: Following intervention the smile improved, with significant changes in availability, execution speed, and quality. SIGNIFICANCE: This study supports these rehabilitation techniques to maximize quality of smiling following FNP. EBM rating: B-2b.  相似文献   
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A dose-escalation study of the calcium ion entry blocking drug nicardipine was performed using large dose infusions in 67 patients with recent aneurysmal subarachnoid hemorrhage (SAH). A safe, potentially therapeutic dose of the drug was determined. Patients admitted within 7 days of SAH from a documented cerebral aneurysm were entered into the study if no spasm was present on the initial angiogram. Nicardipine was administered as a continuous intravenous infusion throughout the 14-day period after SAH, regardless of the timing of surgery. To determine the safest possible dose, nicardipine was administered at seven dose levels from 0.01 to 0.15 mg/kg/hr. The total daily doses ranged from 27.7 mg to 375.0 mg. A follow-up angiogram was carried out on all 67 patients 7 to 10 days after SAH. Computerized tomography and neurological examinations were used to determine the presence of cerebral infarction. No major adverse effects, unexpected reactions, or permanent sequelae could be attributed to nicardipine. A decline in blood pressure was noted following administration of the drug. This occurred more frequently among patients given the largest dose but did not produce clinical problems or require discontinuation of the drug. Favorable outcomes were noted in 52 patients (78%). Vasospasm was found by arteriography in 31 patients (46%). A dose-related trend was noted: only eight (24%) of 33 patients treated at the highest dose level (approximately 10 mg/hr) developed arteriographic evidence of vasospasm. Symptomatic vasospasm was diagnosed in only two (6%) of 33 patients treated with this dose. Of the 34 patients receiving the lower dose levels, angiographic spasm was observed in 68% and symptomatic vasospasm in 27%. No deaths due to vasospasm occurred. Nicardipine appears to prevent both vasospasm and cerebral ischemia after SAH. A multicenter randomized double-blind trial to test this hypothesis is planned.  相似文献   
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