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31.
Cyclooxygenase-2 expression in colorectal cancer liver metastases   总被引:5,自引:0,他引:5  
Cyclooxygenase-2 (COX-2) is up-regulated in 85-90% of primary human colorectal cancers and is a putative target for the chemopreventative activity of non-steroidal anti-inflammatory drugs. However, COX-2 expression by human colorectal cancer liver metastases has been poorly characterized. We studied a consecutive series of 38 patients who underwent liver resection for metastatic disease, for whom long-term (up to 57 months), prospective follow-up data were available. Semi-quantitative immunohistochemistry for COX-2 was performed on 54 metastases from 35 patients, for whom adequate histological material was available. Diffuse cytoplasmic staining for COX-2 protein was detected in cancer cells in 100% of metastases (COX-2 score 1, n=25; score 2, n=29). There was no relationship between metastasis size or differentiation grade and the level of COX-2 protein expression. There was no difference in colorectal cancer-free or overall survival between patients with high (score 2) and low (score 1) COX-2 scores (Kaplan–Meier survival analysis and log rank test, both P=0.97). Multivariate Cox regression analysis identified age, incomplete resection and presence of extra-hepatic disease as independent predictors of disease-free and overall survival following surgery. COX-2 protein was also localized to a subset of stromal fibroblasts and mononuclear cells within metastases as well as hepatocytes from resection specimens. COX-2 protein was expressed by cancer cells in all human colorectal cancer liver metastases which were studied. Investigation of the effect of selective COX-2 inhibition on metastasis growth and metastasis cancer cell proliferation/apoptosis in vivo are warranted.  相似文献   
32.
Inflammation in the lung can lead to increased expression of inducible nitric oxide synthase (iNOS) and enhanced NO production. It has been postulated that the resultant highly reactive NO metabolites may have an important role in host defence, although they might also contribute to tissue damage. However, in a number of inflammatory lung diseases, including bronchiectasis, iNOS expression is increased but no elevation of airway NO can be detected. A potential explanation for this finding is that NO is rapidly scavenged by reaction with superoxide radicals, forming peroxynitrite, which is preferentially metabolized via nitration and nitrosation reactions. To test this hypothesis, anaesthetized, specific pathogen-free rats were inoculated with Pseudomonas aeruginosa incorporated into agar beads (chronically infected group) or sterile agar beads (control group). Ten to 15 days later, the lungs were isolated and fixed. Pseudomonas organisms were isolated from the lungs of the chronically infected group. These lungs showed extensive inflammatory cell infiltration and tissue damage, which were not observed in control lungs. Expression of iNOS was increased in the chronically infected group when compared with the control group. However, the mean number of cells staining for nitrotyrosine in the chronically infected group was not significantly different from that in the controls, nor was there an excess of nitrotyrosine, nitrate, nitrite or nitrosothiol concentrations in the infected lungs. Thus, no evidence was found of increased NO metabolites in chronically infected lungs, including products of the peroxynitrite pathway. These findings suggest that chronic infection does not cause increased iNOS activity in the lung, despite increased expression of iNOS.  相似文献   
33.
Objectives Hope is important in determining positive outcomes in a range of chronic illnesses. This study examined the role of hope in adjustment to end‐stage renal failure (ESRF) and consequent dialysis. Design A cross‐sectional design examined the ability of hope to predict adjustment to ESRF over and above other relevant variables. Methods Individuals receiving dialysis at 4 units in the North‐West UK were invited to take part in the study. 103 questionnaire packs were included in the analysis. Multiple regression equations determined whether hope was able to predict significant variance in adjustment over and above that accounted for by other factors (demographic and illness‐related factors, perceived control, and social support). Measures of anxiety, depression, and quality of life constituted a multidimensional measure of adjustment to ESRF. Results Each of the regression models was significant. Hope emerged as an independent significant predictor in five of the multiple regressions: anxiety; depression; effects and symptoms of kidney disease; and mental health quality of life. Age also emerged as an important predictor of outcome. Conclusions It appears that hope is a significant predictor of adjustment to ESRF. Clinical implications of this research are discussed, along with suggestions for future research.  相似文献   
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Neural activity, as measured immunohistochemically by the presence of Fos protein, was determined in the lamina terminalis, a thin strip of tissue forming the anterior wall of the third brain ventricle, after adrenalectomy. Several weeks after surgery, the adrenalectomized rats were maintained with access to water and a low sodium diet for five days. In addition, hypertonic (0.5M) NaCl solution was available for the entire five-day period (sodium available) or only during the first four days (sodium unavailable). The number of neurons expressing Fos, determined at the end of the fifth day, was increased in the adrenalectomized rats with or without NaCl solution to drink. Fos activity in the median preoptic nucleus was increased only in adrenalectomized rats without access to NaCl solution. Treatment of adrenalectomized rats with the sodium-retaining mineralocorticoid hormone, deoxycorticosterone, at the end of the fourth day, decreased Fos expression in the subfornical organ and the organum vasculosum of the lamina terminalis when NaCl solution was available but not when the NaCl solution was unavailable. In the adrenalectomized rats with NaCl solution available, mineralocorticoid treatment decreased both urinary sodium excretion and daily sodium intake. Brain nuclei in the lamina terminalis also became activated in intact rats made sodium deplete by treatment with the diuretic, furosemide. Relative to sodium-deplete intact rats, however, sodium-deplete adrenalectomized rats had a greater number of neurons expressing Fos in the organum vasculosum. Treatment of sodium-deplete rats, adrenalectomized or intact, with the angiotensin II-type 1 receptor antagonist, ZD7155, decreased sodium intake and Fos expression in the subfornical organ but not in the organum vasculosum of the lamina terminalis or median preoptic nucleus.In conclusion, the results demonstrated that activation of the brain nuclei located in the lamina terminalis of adrenalectomized rats was primarily related to sodium deficit and not to the absence of the mineralocorticoid hormones, although the adrenal hormones may have a role in limiting the activation of organum vasculosum of the lamina terminalis during sodium depletion. Furthermore, the results obtained with the administration of the angiotensin receptor antagonist are consistent with the proposal that sodium appetite of the sodium-deplete rat, adrenalectomized or intact, is mediated by circulating angiotensin II acting in the subfornical organ.  相似文献   
36.
In most research dealing with biological abnormalities in depression, the clinical diagnosis of depression is made and the occurrence of a biological abnormality, for example, reduced REM latency, is documented. In this study, that design was reversed; REM latency was used as a grouping variable to assess empirically the "biological" priority of Research Diagnostic Criteria endogenous symptoms. We found that terminal insomnia, pervasive anhedonia, unreactive mood, and appetite loss were most likely to discriminate among "reduced" and "nonreduced" REM latency depressions at various threshold values. Contrary to expectation, diurnal mood variation was found equivalently in all categories of REM latency studied. Implications for clinical decision making based on endogenous symptoms are discussed.  相似文献   
37.
A recent necropsy study has shown that 80% of patients with the Wernicke-Korsakoff syndrome were not diagnosed as such during life. Review of the clinical signs of these cases revealed that only 16% had the classical clinical triad and 19% had no documented clinical signs. The incidence of clinical signs in this and other retrospective pathological studies is very different from that of prospective clinical studies. This discrepancy may relate to "missed" clinical signs but the magnitude of the difference suggests that at least some cases of the Wernicke-Korsakoff syndrome may be the end result of repeated subclinical episodes of vitamin B1 deficiency. In order to make the diagnosis, clinicians must maintain a high index of suspicion in the "at risk" group of patients, particularly alcoholics. Investigations of thiamine status may be helpful and if the diagnosis is suspected, parenteral thiamine should be given.  相似文献   
38.
BackgroundAccurate resuscitation of pediatric patients with large thermal injury is critical to achieving optimal outcomes. The goal of this project was to describe the degree of variability in resuscitation guidelines among pediatric burn centers and the impact on fluid estimates.MethodsFive pediatric burn centers in the Pediatric Injury Quality Improvement Collaborative (PIQIC) contributed data from patients with ≥15% total body surface area (TBSA) burns treated from 2014 to 2018. Each center's resuscitation guidelines and guidelines from the American Burn Association were used to calculate estimated 24-h fluid requirements and compare these values to the actual fluid received.ResultsDifferences in the TBSA burn at which fluid resuscitation was initiated, coefficients related to the Parkland formula, criteria to initiate dextrose containing fluids, and urine output goals were observed. Three of the five centers’ resuscitation guidelines produced statistically significant lower mean fluid estimates when compared with the actual mean fluid received for all patients across centers (4.53 versus 6.35 ml/kg/% TBSA, p < 0.001), (4.90 versus 6.35 ml/kg/TBSA, p = 0.002) and (3.38 versus 6.35 ml/kg/TBSA, p < 0.0001).ConclusionsThis variation in practice patterns led to statistically significant differences in fluid estimates. One center chose to modify its resuscitation guidelines at the conclusion of this study.  相似文献   
39.
Archives of Sexual Behavior - Research on consensual non-monogamy (CNM) has largely focused on CNM behavior, while less attention has been given to attitudes toward and willingness to engage in...  相似文献   
40.
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