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排序方式: 共有9102条查询结果,搜索用时 15 毫秒
101.
Luisa Di Marzio Alfredo Di Leo Benedetta Cinque Donatella Fanini Alessio Agnifili Pasquale Berloco Michele Linsalata Dionigi Lorusso Michele Barone Claudio De Simone Maria Grazia Cifone 《Cancer epidemiology, biomarkers & prevention》2005,14(4):856-862
OBJECTIVES: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues. MATERIALS AND METHODS: The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed. RESULTS: Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls. CONCLUSION: These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms. 相似文献
102.
Yi Ren Brian Cao Simon Law Yi Xie Ping Yin Lee Leo Cheung Yongxong Chen Xin Huang Hiu Man Chan Ping Zhao John Luk George Vande Woude John Wong 《Clinical cancer research》2005,11(17):6190-6197
PURPOSE: Hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, c-Met, play important roles in tumor development and progression. In this study, we measured the serum HGF levels in patients with esophageal squamous cell carcinoma (ESCC) to evaluate its relationships with clinicopathologic features and the role of HGF in ESCC. EXPERIMENTAL DESIGN: One hundred and forty-nine patients with ESCC were studied. Pretherapy serum was collected and ELISA was used to detect the concentrations of HGF, vascular endothelial growth factor (VEGF), and interleukin 8 (IL-8). The function of HGF was shown by invasion chamber assay. RESULTS: Pretherapy serum HGF was found to be significantly higher in patients with ESCC than in control subjects. The levels of HGF correlated significantly with advanced tumor metastasis stage and survival. Multivariate analyses showed that serum HGF level in cell migration was an independent prognostic factor. Increased HGF serum levels correlated positively with serum levels of VEGF and IL-8. Our results also showed that HGF was overexpressed in ESCC tissues and cell lines. In vitro study showed that HGF could stimulate ESCC cell to express VEGF and IL-8 and markedly enhance invasion and migration of ESCC cells. Furthermore, HGF-induced IL-8 and VEGF expression was dependent on extracellular signal-regulated kinase signaling pathways. The inhibition of extracellular signal-regulated kinase activation reduced HGF-mediated IL-8 and VEGF expression. CONCLUSIONS: Our results suggest that serum HGF may be a useful biomarker of tumor progression and a valuable independent prognostic factor in patients with ESCC. HGF may be involved in the progression of ESCC as an autocrine/paracrine factor via enhancing angiogenesis and tumor cell invasion and migration. 相似文献
103.
BACKGROUND: Deep-vein thrombosis (DVT) and pulmonary embolism (PE) are the most important causes of morbility and mortality in patients submitted to surgical intervention: some peculiar factors of laparoscopic surgery can modify their risk. The aim of this study is to evaluate possible variations of the fibrinolytic system after cholecystectomy. METHODS: Eighteen patients affected by symptomatic and non-complicated gallstones have been included in this study. They were divided into two groups of nine patients each: the first group was submitted to laparoscopic cholecystectomy (LC) and the second to open cholecystectomy (OC). Antitrombin III (ATIII), fibrinogen degradation products (FDP), tissue plasminogen activator (tPA), and plasminogen activator inhibitor (PAI) have been evaluated preoperatively and 6, 12, 24 and 48 hours after the operation. RESULTS: The levels of ATIII did not present significantly variations. The FDP in both groups were significantly increased 48 hours after open cholecystectomy. Levels of PAI instead were increased in comparison to the basal values at 6, 12, 24, 48 hours with p < 0.05; p < 0.01 and p < 0.05 respectively in patients submitted to OC, in the LC group no variations were observed; a comparison between the groups showed a significant modification (p < 0.05) only at the 12th hour. CONCLUSIONS: The early mobilization of patients in the postoperative course and the lower invasion of LC can oppose the prothrombotic effect in the lower limbs. 相似文献
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107.
Martin Dres Ewan C. Goligher Leo M. A. Heunks Laurent J. Brochard 《Intensive care medicine》2017,43(10):1441-1452
Diaphragm weakness is highly prevalent in critically ill patients. It may exist prior to ICU admission and may precipitate the need for mechanical ventilation but it also frequently develops during the ICU stay. Several risk factors for diaphragm weakness have been identified; among them sepsis and mechanical ventilation play central roles. We employ the term critical illness-associated diaphragm weakness to refer to the collective effects of all mechanisms of diaphragm injury and weakness occurring in critically ill patients. Critical illness-associated diaphragm weakness is consistently associated with poor outcomes including increased ICU mortality, difficult weaning, and prolonged duration of mechanical ventilation. Bedside techniques for assessing the respiratory muscles promise to improve detection of diaphragm weakness and enable preventive or curative strategies. Inspiratory muscle training and pharmacological interventions may improve respiratory muscle function but data on clinical outcomes remain limited. 相似文献
108.
Rupesh Agrawal Hnin Hnin Oo Praveen Kumar Balne Lisa Ng Louis Tong Yee Sin Leo 《Ocular immunology and inflammation》2018,26(5):654-659
Zika virus (ZIKV), a mosquito-borne flavivirus, is the latest global health concern. Transmission is mainly via Aedes mosquitoes and the infection can be diagnosed on molecular or serologic testings. It typically causes a mild self-remitting illness of low-grade fever, maculopapular rash, and myalgia, but when severe, it is associated with neurological deficits and congenital structural defects. Ocular manifestations are usually mild like nonpurulent conjunctivitis in adults, though it may be linked to uveitis, maculopathy, and hypertensive iridocyclitis. Ocular signs seem to be more significant in congenital ZIKV—macular pigment mottling, neuroretinal atrophy with macular involvement, iris coloboma, and changes in retinal vasculature are noted in infants with infected mothers. Risk factors include ZIKV infection in first trimester and smaller cephalic diameter at birth. Hence, ophthalmic examination in newborns is now recommended. Currently, prevention and active surveillance are integral as there is no known vaccine, and treatment is only symptomatic. 相似文献
109.
Eleven polymorphic and three monomorphic microsatellite loci were developed for Dermacentor albipictus using three methods: (1) screening of a microsatellite enriched genomic DNA library, (2) in silico screening of EST libraries, and (3) adapting loci previously developed for D. variabilis (Say). An average of 4.91 alleles was detected per polymorphic locus. Average observed and expected heterozygosity among polymorphic loci was 0.518 and 0.623 respectively. No locus was significantly linked and one locus exhibited significant deviation from Hardy?CWeinberg equilibrium. All loci amplified with varying success in D. andersoni and D. variabilis. These microsatellite loci will be useful for studying the species boundaries and genetic diversity of Dermacentor albipictus in North America. 相似文献
110.