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Abstract

The ability of an experimental lazaroid, U74389G, to prevent damage to hippocampal CA 1 cytoarchitecture due to transient global ischemia was studied by light and electron microscopy. Post-ischemic rats were given a single i.p. dose of lazaroid (6 or 18 mg kg-1) at 5 min after revival by cardiopulmonary resuscitation (CPR). Without lazaroid treatment the number of normal-appearing neurons in the CA1 region declined from a normal value of 75.49± 2.21 to 8.40± 10.08 per 100 μ,m2 on day 7 after the ischemic episode, and there was extensive damage visible in the cytoarchitecture of this region. In lazaroid treated rats, the normal cytoarchitecture was retained and the number of normal-appearing cells was maintained at 15.1O± 2.22 per 100 ¼,m2? Ultrastructure studies indicated that pyknotic pyramidal cells laden with Pysosomal aggregates were common in untreated post-ischemic rats but rare in lazaroid-treated rats. These results indicate that U74389G maintained the structural integrity of this region of the brain after transient global ischemia and suggest that this lazaroid may be an effective neuroprotectant. [Neural Res 1997; 19: 431-434]  相似文献   
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Nonalcoholic fatty liver disease is a type of hepatic steatosis that is not only associated with critical metabolic risk factors but can also result in advanced liver diseases. Ultrasound parametric imaging, which is based on statistical models, assesses fatty liver changes, using quantitative visualization of hepatic-steatosis–caused variations in the statistical properties of backscattered signals. One constraint with using statistical models in ultrasound imaging is that ultrasound data must conform to the distribution employed. Small-window entropy imaging was recently proposed as a non–model-based parametric imaging technique with physical meanings of backscattered statistics. In this study, we explored the feasibility of using small-window entropy imaging in the assessment of fatty liver disease and evaluated its performance through comparisons with parametric imaging based on the Nakagami distribution model (currently the most frequently used statistical model). Liver donors (n?=?53) and patients (n?=?142) were recruited to evaluate hepatic fat fractions (HFFs), using magnetic resonance spectroscopy and to evaluate the stages of fatty liver disease (normal, mild, moderate and severe), using liver biopsy with histopathology. Livers were scanned using a 3-MHz ultrasound to construct B-mode, small-window entropy and Nakagami images to correlate with HFF analyses and fatty liver stages. The diagnostic values of the imaging methods were evaluated using receiver operating characteristic curves. The results demonstrated that the entropy value obtained using small-window entropy imaging correlated well with log10(HFF), with a correlation coefficient r?=?0.74, which was higher than those obtained for the B-scan and Nakagami images. Moreover, small-window entropy imaging also resulted in the highest area under the receiver operating characteristic curve (0.80 for stages equal to or more severe than mild; 0.90 for equal to or more severe than moderate; 0.89 for severe), which indicated that non–model-based entropy imaging—using the small-window technique—performs more favorably than other techniques in fatty liver assessment.  相似文献   
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Chronic lymphocytic leukemia is one of the most common leukemias in the western world and consists of many chromosome aberrations. We report the case of a 74-year-old male patient with chronic lymphocytic leukemia with complex variant translocations t(8;22)(q24;q11) and der(8)t(6;8)(p21;p21) identified by chromosome banding analysis and confirmed by fluorescence in situ hybridization analysis of interphase cells. Because of the rarity of these changes, possible molecular mechanisms associated with this karyotype are discussed.  相似文献   
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Background

Surgery for pancreatic cancer yields significant morbidity and mortality risks and survival is limited. Therefore, the influence of complications on quality of life (QoL) after pancreatic surgery is important. This study compares QoL in patients with and without severe complications after surgery for pancreatic (pre-)malignancy.

Methods

This prospective cohort study scored complications after pancreatic surgery according to the Clavien–Dindo system and the definitions of the International Study Group of Pancreatic Surgery. QoL was measured by the RAND36 questionnaire, the European Organization for Research and Treatment of Cancer core questionnaire (QLQ-C30) and the pancreas specific QLQ-PAN26. QoL in patients with severe complications was compared with QoL in patients with no or mild complications over a period of 12 months. Analysis was performed with linear mixed models for repeated measurements.

Results

Between March 2012 and July 2016, 137 patients were included. Sixty-eight patients (50%) had at least 1 severe complication. There were no statistically significant and clinically relevant differences between both groups in QoL up to 12 months after surgery.

Conclusion

In this study, no differences in QoL between patients with and without severe postoperative complications were encountered during the first 12 months after surgery for pancreatic (pre-)malignancy.

Trial registration

http://www.clinicaltrials.gov Identifier: NCT02175992.  相似文献   
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