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41.
Background. Little is known about preload-dependent cardiac function after brain death (BD) and subsequent graft preservation.

Methods. A validated model of BD in rabbits was developed and myocardial performance was studied after BD induction and 1 hour of subsequent global hypothermic ischemia using a validated rabbit model and an isolated work-performing heart preparation.

Results. Significant decreases in stroke work, left ventricular contractility, and left ventricular relaxation were observed 2 hours after BD. After global hypothermic ischemia, significant decreases in stroke work, left ventricular contractility, and left ventricular relaxation were observed in the BD group compared with controls. Cardiac output and coronary flow were also significantly decreased in BD hearts compared with controls. Creatine kinase release was increased by 32.5% in BD hearts compared with controls.

Conclusions. In a rabbit model, BD combined with global hypothermic ischemia causes a significant decrease in left ventricular function compared with global hypothermic ischemia. This dysfunction may be attributed to a significant decrease in coronary flows in BD hearts.  相似文献   

42.
The epsilon-sarcoglycan gene (SGCE) on human chromosome 7q21 has been reported to be a major locus for inherited myoclonus-dystonia. Linkage to the SGCE locus has been detected in the majority of families tested, and mutations in the coding region have been found recently in families with autosomal dominant myoclonus-dystonia. To evaluate the relevance of SGCE in myoclonus-dystonia, we sequenced the entire coding region of the epsilon-sarcoglycan gene in 16 patients with either sporadic or familial myoclonus-dystonia. No mutations were found. This study suggests that epsilon-sarcoglycan does not play an important role in sporadic myoclonus-dystonia and supports genetic heterogeneity in familial cases.  相似文献   
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44.
Abstract End-stage liver disease caused by the hepatitis C virus is a major indication for liver transplantation. However, recurrence of hepatitis in the graft is a major issue. HCV re-infection after transplantation is almost constant, and recent data confirm that it significantly impairs patient and graft survival. Factors that may influence disease severity and consequent progression of HCV graft injury remain unclear. Chronic HCV infection develops in 60%–80% of patients, and 6%–28% ultimately progress to cirrhosis within 5 years. Pre-transplantation antiviral treatment is not easily related to poor tolerance. Attempts to administer prophylactic post-transplantation antiviral treatment are under evaluation but are limited by antiviral drug side effects. Treatment of established graft lesions with interferon or ribavirin as single agents has been disappointing. Combination therapy gave promising results, with sustained virological response in 25% of patients, but indications, modality and duration of treatment should be assessed.  相似文献   
45.
Background: The analgesic nefopam does not compromise ventilation, is minimally sedating, and is effective as a treatment for postoperative shivering. The authors evaluated the effects of nefopam on the major thermoregulatory responses in humans: sweating, vasoconstriction, and shivering.

Methods: Nine volunteers were studied on three randomly assigned days: (1) control (saline), (2) nefopam at a target plasma concentration of 35 ng/ml (low dose), and (3) nefopam at a target concentration of 70 ng/ml (high dose, approximately 20 mg total). Each day, skin and core temperatures were increased to provoke sweating and then reduced to elicit peripheral vasoconstriction and shivering. The authors determined the thresholds (triggering core temperature at a designated skin temperature of 34[degrees]C) by mathematically compensating for changes in skin temperature using the established linear cutaneous contributions to control of each response.

Results: Nefopam did not significantly modify the slopes for sweating (0.0 +/- 4.9[degrees]C [middle dot] [mu]g-1 [middle dot] ml; r2 = 0.73 +/- 0.32) or vasoconstriction (-3.6 +/- 5.0[degrees]C [middle dot] [mu]g-1 [middle dot] ml; r2 = -0.47 +/- 0.41). In contrast, nefopam significantly reduced the slope of shivering (-16.8 +/- 9.3[degrees]C [middle dot] [mu]g-1 [middle dot] ml; r2 = 0.92 +/- 0.06). Therefore, high-dose nefopam reduced the shivering threshold by 0.9 +/- 0.4[degrees]C (P < 0.001) without any discernible effect on the sweating or vasoconstriction thresholds.  相似文献   

46.
47.
The purpose of this clinical trial was to evaluate the reliability and time saved with a plasma arc curing unit (Apollo 95E, Dental/Medical Diagnostic Systems, Woodland Hills, Calif) compared with a conventional curing unit (Ortholux XL 3000, 3M Unitek, St Paul, Minn) for direct bracket bonding with resin adhesive. Forty-five patients were involved in the study, and 608 brackets were bonded in a contralateral quadrant pattern. The patients were followed for a mean (+/- standard deviation) period of 11 +/- 3.2 months. Survival analysis was carried out to compare the failure rate for the 2 techniques. The time required for bonding with each technique was also recorded. The mean survival time was 399 days, and there were no significant differences in survival time between the 2 bonding methods. Twelve bonding failures were reported with each technique. The curing time per bracket was significantly reduced with the plasma curing light compared with a conventional curing unit (65 +/- 19 vs 82 +/- 31 seconds). The plasma arc curing light can save chair-time without affecting the bonding failure rate.  相似文献   
48.
OBJECTIVE: To assess the therapeutic effect of the extent of lymph node dissection performed in patients with a stage pI non-small-cell lung cancer (NSCLC). METHODS: We analysed data on 465 patients with stage I NSCLC who were treated with surgical resection and some form of lymph node sampling. The median number of lymph node sampled was 10 and the median number of ipsilateral mediastinal lymph node stations sampled was two. We chose to define a procedure that harvested 10 or more lymph nodes and sampled two or more ipsilateral mediastinal stations as a lymphadenectomy, by contrast with sampling when one or both criteria were not satisfied. The effect of the surgical techniques: lymph node sampling (LS; n=207) vs. lymphadenectomy (LA; n=258) on 30-day mortality and overall survival were investigated. RESULTS: A total of 6244 lymph nodes was examined, including 4306 mediastinal lymph nodes. The mean (+/-SD) numbers of removed lymph nodes were 7+/-6.1 per patient following LS vs.18.6+/-9.3 following LA (P=0.001). An average mean of 1+/-0.90 mediastinal lymph node station per patient was sampled following LS vs. 2.7+/-0.8 following LA (P<10(-6)). Overall 30-day mortality rates were 2.4 and 3.1%, respectively. LA was disclosed as a favourable prognosticator at multivariate analysis (Hazard Risk: 1.43; 95% Confidence Interval: 1.00-2.04; P=0.048), together with younger patient age, absence of blood vessels invasion, and smaller tumour size. CONCLUSIONS: Importance of lymph node dissection affects patients outcome, while it does not enhance the operative mortality. A minimum of 10 lymph nodes assessed, and two mediastinal stations sampled are suggested as possible pragmatic markers of the quality of lymphadenectomy.  相似文献   
49.
Insomnia in psychiatric patients is frequently underestimated in clinical practice. Usually drugs are prescribed for the treatment of this disorder but non-pharmacological intervention can be successfully used. The present study aimed at evaluating the efficacy of a two-session psychoeducational intervention in improving persistent non-organic insomnia and reducing the administration of PRN therapy in severely mentally ill patients. A pre-post study was performed on 36 psychiatric patients admitted to a residential psychiatric unit. The Nocturnal Sleep Onset Scale (NSOS) and Daytime Sleepiness Scale (DSS), the sleep onset latency, the time awake after sleep onset and the numbers of awakenings were gathered 2 weeks before the intervention (T0), immediately prior the intervention (T1), 2 weeks after the last session of the intervention (T2) and a 3-month follow-up (T3). The total number of administrations of PRN therapy from T0 to T1 and from T1 to T2 were also examined. A significant reduction was shown on the NSOS, the sleep onset latency and in the time awake after sleep onset from T1 to T2 and from T1 to T3, while no significant difference was found between T0 and T1. A significant decrease on the mean number of administrations of PRN therapy was also found between 15 days before the intervention (T0-T1) and 15 days after intervention (T1-T2). The initial results of this study seems to suggest the possible efficacy of a short-term psychoeducational intervention on improving persistent non-organic insomnia in severely mentally ill patients. Further control studies are necessary to confirm these findings.  相似文献   
50.
A 44-year-old man with right-sided herpes zoster ophthalmicus (HZO) developed ipsilateral third and sixth cranial nerve palsies and first-division trigeminal (fifth cranial nerve) sensory loss. MRI revealed contrast enhancement of the cisternal and cavernous portions of the third cranial nerve and high signal on a FLAIR sequence within the ipsilateral medulla at the presumed location of the trigeminal nucleus and tract. To our knowledge, this is the first report of the combination of these imaging findings in HZO.  相似文献   
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