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101.
102.
Cytochrome P4502E1 (CYP2E1) plays an important role in ROS production thus favouring accelerated membrane lipid peroxidation. This isoform is strongly expressed in the liver but it can be also found in lymphocytes. As such, lymphocyte may provide a non-invasive accessible pool for screening CYP2E1 expression in man. We have, therefore, analysed CYP2E1 expression and activity in lymphocyte microsomes from 12 healthy controls, 11 type 1 and 12 type 2 diabetic subjects by using Western blot and enzymatic activities. Immunoblotting did not show difference among CYP2E1 protein bands in controls, type 1 and type 2 diabetics. To assess CYP2E1 activity we used the 7-ethoxy-4-trifluoromethylcoumarin (7-EFC), as a fluorescent substrate. The rate of deethylation of 7-EFC from controls did not differ from type 1 and type 2 diabetic subjects. The lack of any difference in CYP2E1 activity also was confirmed by the NADPH-dependent microsomal lipid peroxidation CCL4-induced assay showing similar peroxidation rates among controls and diabetic subjects. The results show that CYP2E1 expression/activity in lymphocytes is not enhanced in diabetes.  相似文献   
103.
Free-radical formation may play a role in postoperative complications of phacoemulsification (e.g., corneal endothelium damage from mechanical injury). The present experiments were aimed at investigating whether different molecular weight ranges (2000-2600, 2600-3200, or 3200-3800 kDa) of hyaluronan may influence free radical formation, corneal endothelium damage, and inflammation parameters after phacoemulsification in the rabbit eye. The viscoelastic substance was injected in the anterior chamber of rabbits' eyes before phacoemulsification, at a 2.5% concentration. The formation of free radicals was determined by adding luminol to the irrigation media and measuring the chemoluminescence in eyes. The corneal endothelial damage was evaluated by measuring the corneal central thickness by pachimetry. The inflammation parameters were measured by calculation in aqueous humor of peak levels of leukocytes and prostaglandin E(2) (PGE(2)) and evaluation in uveal tissue of myeloperoxidase activity. Hyaluronan decreased by about 58-60% free-radical formation during phacoemulsification, reduced by about 76-80% modifications in mean corneal thickness and by about 54-61% the corneal endothelial cell loss in all molecular weight ranges used. No difference was found among various molecular weight ranges. The highest molecular weight range showed to be more potent than the lowest range for reduced number of inflammation cells and level of PGE(2) in aqueous humor. Thus, hyaluronan reduces free-radical formation, exerts protection on the corneal endothelium and exerts anti-inflammation properties after phacoemulsification in rabbits. The latter effect seems to depend on the molecular weight of the substance.  相似文献   
104.
We report the case of a 30-year-old woman with cystic fibrosis (CF) chronically infected with Pseudomonas aeruginosa who delivered and breast-fed a healthy boy. While breast-feeding the woman had to undergo an i.v. antibiotic course with tobramycin, due to pulmonary exacerbation. Tobramycin was not detected in her milk and lactation could be continued. This is the first time that the presence of tobramycin in the milk of a CF woman during i.v. administration has been investigated.  相似文献   
105.
106.
Serum PDGF-AB in pleural mesothelioma.   总被引:2,自引:0,他引:2  
Overexpression of platelet-derived growth factor (PDGF) has been observed in lung and pleural tumors. The aim of this study was to evaluate the diagnostic and prognostic role of serum PDGF in pleural mesothelioma (PM). Four groups of subjects were studied: 93 malignant PM patients, 33 primary non small cell lung cancer patients, 51 subjects exposed to asbestos, defined as high-risk controls, and 24 healthy controls. PDGF-AB mean concentration was higher in PM patients (45.8 ng/ml) than in high-risk controls (33.1 ng/ml) and healthy controls (26.8 ng/ml). Using the cut-off level of 49.8 ng/ml, corresponding to the mean+2SD of PDGF-AB in healthy controls, 43% of PM patients showed positive PDGF-AB levels. Survival was evaluated in 82 PM patients. At the end of the follow-up (median 9.8 months) 80.5% of patients had died. Median survival was 13.1 and 7.9 months for patients with PDGF-AB lower and higher than the cut-off, respectively. Adjusting for age, sex, histology and platelet count, positive PDGF-AB levels were associated with lower survival (OR=1.2, 95%CI: 0.9-1.6), even if not significantly so. In conclusion, serum PDGF may represent a useful additional parameter to prognostic factors already available for PM.  相似文献   
107.
The burden of morbidities affecting cardiovascular and musculoskeletal systems, metabolism, and psychosocial health in young patients with cancer is high. It is alarming that patients and survivors of childhood cancer are less physically active than their healthy peers, since exercise may improve many of these conditions significantly and is associated with reduction in all‐cause mortality in the general population. Systematic integration of exercise programing into cancer care remains an exception, above all in children. Pediatric oncologists may contribute to a culture shift towards educating patients and stakeholders on the benefit of exercise and sports for children and adolescents with cancer.  相似文献   
108.
ABSTRACT

It is commonly assumed that people who are addicted to certain substances would abuse any substance. This position has never been supported by validly collected and analyzed research data. In this study, the authors examine the use of street methadone by heroin addicts seeking their first agonist opioid treatment in a clinical setting. Fifty-four heroin addicts who resorted to street methadone use were compared by socio-demographic, current clinical, and disease-related variables to 251 peers who do not use street methadone. Heroin addicts who resort to street methadone use are more likely to be females and to have a higher degree of education, are less likely to engage in polyabuse (use of more than three substances), are less severely ill, have been addicted for a shorter period of time, and have been seeking treatment sooner in the course of their disease. Also, they suffer from a wider range of psychopathological distress symptoms. In Italy, resorting to street methadone does not seem to be a surrogate form of heroin addiction, but rather represents means of harm reduction, with treatment seeking occurring shortly after its initiation. This should be accounted for when deciding on take-home policies and issues of potential methadone diversion.  相似文献   
109.
Within a few decades half of the patients with non-valvular atrial fibrillation (AF) will be older than 80 years. These patients are at particularly high risk of thromboembolism (Scylla) but also of the hemorrhagic complications of thromboprophylaxis (Charybdis). A frequent compromise is to use as antithrombotic agents instead of vitamin-K antagonists aspirin or other antiplatelet drugs, which are ineffective for thromboprophylaxis in the oldest old and definitely not free from a high risk of severe bleeding. All the new direct anticoagulants currently licensed (dabigatran, rivaroxaban, apixaban) are at least as effective as warfarin for thromboprophylaxis in AF, but the risk of the intracranial bleeding, the most feared complication of anticoagulant therapy, is at least halved. In the oldest patients of 80 years of age or more preliminary data, available so far only for dabigatran, indicate that the favorable outcomes of direct anticoagulants are also present in this subgroup, often left untreated for fear of intracranial bleeding. The choice between the different direct anticoagulants is driven by the presence or not of renal insufficiency, the presence and degree of multimorbidity and polypharmacy and by the likelihood or not of poor treatment adherence in patients who are often frail and with some degree of cognitive impairment.  相似文献   
110.
This statement, focused on melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with melanonychia and to assist choosing appropriate management for melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.  相似文献   
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