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1.
2.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
3.
Functional recovery, the goal of treatment, has long been overlooked in the assessment of effectiveness of pharmacological treatments. However, with the recent shift in paradigm, from syndromal–symptomatic recovery to functional recovery, there appears to be a new interest in the definition and evaluation of functional recovery. Since functional recovery lags symptomatic recovery, sometimes by months or years, the attainment of functional recovery will be determined by both efficacy and long-term compliance. Quetiapine, due to its efficacy in both mania and depression, and effect on cognition may lead to improved functioning in patients with bipolar disorder.  相似文献   
4.
Hemangioma of the nasal vault: MR and CT features   总被引:1,自引:0,他引:1  
W P Dillon  P M Som  W Rosenau 《Radiology》1991,180(3):761-765
Six patients with a history of epistaxis (five patients) or nasal obstruction (one patient) were found to have a capillary hemangioma of the nasal vault that involved one or more nasal turbinates. Four patients underwent computed tomographic (CT) examination; two of these also underwent magnetic resonance (MR) imaging. Four others underwent only MR imaging. At CT and MR, all of the lesions were well circumscribed and intensely enhancing, with contralateral deviation of the nasal septum. Remodeling of the surrounding bone was present in three patients. On T1-weighted MR images, the masses were intermediate in signal intensity. Varying degrees of T2 shortening were shown on T2-weighted MR images, with an appearance that suggested the presence of blood products surrounding an inner matrix of higher-signal-intensity tumor. Intense enhancement at CT and MR assisted differentiation of tumor from retained sinonasal secretions. In two patients, external carotid arteriography revealed small foci of pooling contrast material; in one of these patients, arteriovenous shunting was also present. Pathologic examination in all patients demonstrated capillary hemangiomas with varying degrees of fibrosis and hemosiderin deposition.  相似文献   
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6.
Congenital thoracic ectopic kidney is a very rare developmental anomaly and the rarest form of all ectopic kidneys. It is usually asymptomatic and discovered incidentally on routine chest radiography. Herein we reported the first case of staghorn stone in a thoracic kidney managed successfully by percutaneous nephrolithotomy.  相似文献   
7.
Although acute thyroiditis often has a distinctive clinical presentation, this relatively uncommon entity can occasionally be confused with other inflammatory processes. In general, the earlier the diagnosis of acute thyroiditis is established, the lower is the frequency and severity of its attendant complications. Computed tomography (CT) is an extremely useful modality in establishing the diagnosis early because it can evaluate iodine content of the thyroid gland and provides more accurate mapping than ultrasound and nuclear medicine techniques. Three patients with acute thyroiditis--two with suppuration--are presented and the CT findings and clinical aspects of this disease are reviewed.  相似文献   
8.
9.
Which patient, which pump?   总被引:1,自引:0,他引:1  
  相似文献   
10.
X-ray fluorescence analysis has been used for measurement of lead in paint for more than a decade. The early systems provided a nondestructive alternative technology to laboratory-based technologies, but were somewhat time consuming and often led to inconclusive results. The procedure required manual substrate correction, multiple measurements, operator's discretion in validating a measurement due to interfering elements and laboratory analysis of inconclusive samples. A new instrument, the RMD LPA-1 system, has been developed based on X-ray fluorescence technology that addresses all of the drawbacks to the older systems. This new system uses a carefully designed and controlled geometry and modern microprocessor technology to automatically provide a rapid quantitative measurement of lead in paint with a 95% confidence level. The improved precision and accuracy achieved with this system are due to geometric enhancements and a mathematical approach which incorporates corrections for both random and systematic errors such as matrix effects and Compton scatter. This technology has been incorporated in a hand-held X-ray fluorescence lead paint analyzer system. A key design philosophy for this system was to maintain a very narrow, task-specific focus, the system was not designed to be an all purpose XRF analyzer, rather it is optimized to meet regulatory requirements of lead paint testing in the most efficient manner. The development of the LPA-1 system is an example of what can be accomplished by listening to the needs and desires of the users, rethinking the design of an existing technique and incorporating modern microprocessor technology.  相似文献   
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