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排序方式: 共有768条查询结果,搜索用时 15 毫秒
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George V Dedoussis Demosthenes B Panagiotakos Nikoleta V Vidra Eirini Louizou Christina Chrysohoou Athanasios Germanos Yannis Mantas Savas Tokmakidis Christos Pitsavos Christodoulos Stefanadis 《Genetics in medicine》2005,7(6):411-416
PURPOSE: We investigated the association of a polymorphism within the promoter of TauNuF-alpha locus at the position -308 on the likelihood of having acute coronary syndromes (ACS) in Greek adults. METHODS: We studied demographic, lifestyle, and clinical information in 237 hospitalized patients (185 males) with a first event of an ACS and 237 matched by age and sex (controls) without any clinical evidence of coronary heart disease. Genotyping was performed by PCR-RFLP analysis. RESULTS: The genotype frequencies were in patients, 87% (n = 206), 12% (n = 29), and 1% (n = 2) for G/G, G/A, and A/A, and in controls, 96% (n = 227), 4% (n = 10), and 0% (n = 0) for G/G, G/A, and A/A, respectively (P = 0.04). After adjusting for age and sex, as well as various potential confounders, we observed that G/A or A/A genotypes were associated with 1.94-fold higher odds (95% CI 1.06 to 3.68) of ACS compared to G/G homozygotes. No gene to-gender or to-clinical syndrome interactions were observed. Further subgroup analysis showed that the distribution of TNF-alpha -308G>A polymorphism was associated with the presence of family history of CHD in patients, but not in controls. In particular, in G/A and A/A patients 17.2% reported family history of CHD, whereas in G/G patients, 34.5% reported family history (P = 0.036). CONCLUSIONS: Our findings may state a hypothesis of an association between the -308G>A TNF-alpha polymorphism the development of ACS and the presence of family history of CHD, in Greece. 相似文献
23.
P-glycoprotein-mediated multidrug resistance and lymphokine-activated killer cell susceptibility in ovarian carcinoma 总被引:1,自引:0,他引:1
The sensitivity of tumor cells to lysis by natural killer (NK) and interleukin-2 (IL-2)-activated killer (LAK) cells was studied in three ovarian carcinoma cell lines (2780.9S, SKOV-3, and CHOAUXB1), four multidrug-resistant (MDR) variants, and a melphalan-resistant line. The antitumor activity of LAK cells was evaluated both by51Cr release and by conjugate formation assays. Four of four P-glycoprotein-positive (P-gp+) MDR ovarian carcinoma cell line variants were lysed by human LAK cells to a greater extent than were their drug-sensitive counterparts. In contrast, a melphalan-resistant ovarian carcinoma cell line that does not overexpress P-gp (P-gp–) did not exhibit an increased susceptibility to LAK cells relative to its parental cell line. Two of the four P-gp+ MDR ovarian carcinoma cell line variants were tested for human NK cell susceptibility and this was found to be unchanged or decreased. The P-gp+ MDR ovarian carcinoma cell line 2780.AD645 showed a higher frequency of tumor cell binding to LAK cells than did the drug-sensitive parental line. A monoclonal antibody (mAb) against a cell surface epitope of P-gp, MRK16, used at 1 g/ml, enhanced the LAK susceptibility of P-gp+ MDR ovarian carcinoma cell lines. However, when incubation with 10 g/ml MRK-16 antibody (Ab) was followed by 12.5 g/ml F(ab)2 goat anti-mouse (GAM) immunoglobulin (Ig), the increased LAK susceptibility of P-gp+ MDR cell lines was inhibited. These data strongly suggest that P-glycoprotein-positive MDR ovarian carcinoma cells not only are targets for LAK cells, but are more sensitive than their drug-sensitive parental lines. This is in contrast to their susceptibility to NK cells, which is low to start with and remains unchanged or even decreased in MDR cells. It is postulated here that P-gp or associated changes result in a greater frequency of effector-target cell binding, leading to increased LAK cell cytotoxicity. 相似文献
24.
Oxidative stress and enzymatic antioxidant status in patients with nonalcoholic steatohepatitis 总被引:16,自引:0,他引:16
Koruk M Taysi S Savas MC Yilmaz O Akcay F Karakok M 《Annals of clinical and laboratory science》2004,34(1):57-62
Oxidative stress is an important pathophysiological mechanism in nonalcoholic steatohepatitis (NASH). To assess whether there are relationships between oxidative stress and antioxidant enzymes in the development of NASH, we investigated oxidative stress by measuring serum malondialdehyde (MDA) and nitric oxide (NO) and antioxidant status by measuring serum glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and superoxide dismutase (SOD). The study included 18 patients (13 men, 5 women; mean age 42 yr) with biopsy proven NASH and 16 healthy volunteers (10 men, 6 women; mean age 38 yr). Serum levels of MDA, NO, GSH, GSH-Px, GR and SOD were determined by spectrophotometric methods. Serum levels (mean +/- SD) of MDA (6.7 +/- 1.6 vs 2.8 +/- 1.7 nmol/ml, p 0.0001), NO (135 +/- 28 vs 113 +/- 35 mmol/L, p 0.04), GSH (919 +/- 137 vs 770 +/- 128 mmol/L, p 0.003) were increased in patients with NASH vs controls. Serum levels of GSH-Px (1063 +/- 152 vs 1000 +/- 94 U/L) and GR (47 +/- 22 vs 40 +/- 21 U/L) were not singnificantly different in the patients vs controls. However, the serum level of SOD (1.24 +/- 0.32 vs 1.51 +/- 0.37 U/ml, p: 0.04) was significantly decreased. Impaired antioxidant defense mechanisms may be an important factor in the pathogenesis of NASH. Treatment approaches that affect the antioxidant enzymes may be beneficial in patients with NASH. 相似文献
25.
BACKGROUND: Expression of cytokeratins 7 (CK7) and 20 (CK20) may help distinguish the site of origin for metastatic carcinomas. Little is known regarding their expression in biliary tract and pancreatic carcinomas. Our aim was to study the expression of CK7 and CK20 in these tumors. DESIGN: Fifty-three carcinomas of the extrahepatic bile ducts (n = 8), ampulla of Vater (n = 7), gallbladder (n = 11), and pancreas (n = 27), were retrieved from the surgical pathology files of the University of Massachusetts Medical Center. Formalin-fixed, paraffin-embedded sections were immunostained with mouse monoclonal antibodies to CK7 and CK20 using an avidin-biotin immunoperoxidase technique with microwave antigen retrieval. The percentage of cells positive for each antibody was assessed on a scale of 0 to 3 (0, <10%; 1+, 10% to 50%; 2+, 51% to 90%; 3+, >90%). RESULTS: The majority of carcinomas in all groups were positive for CK7 (CK7+) and negative for CK20 (CK20-). Of the CK7+ tumors, the majority of tumors in each group were 3+ positive. CONCLUSIONS: (1) Carcinomas of the extrahepatic biliary tract and pancreas are strongly positive for CK7 and negative for CK20 and can be included in the differential diagnosis of other carcinomas with this profile in metastatic sites. (2) The CK7/CK20 immunostaining profile will not identify the site of origin for tumors with extensive growth in the porta hepatis region. 相似文献
26.
27.
Derya Hopanci Bicakli Msc RD Medine C. Yilmaz PhD RN Serap Aksoylar MD Mehmet Kantar MD Nazan Cetingul MD Savas Kansoy MD 《Pediatric blood & cancer》2012,59(7):1327-1329
We aimed to demonstrate whether enteral nutrition (EN) is feasible in daily practice of hematopoietic stem cell transplantation (HSCT).Nutritional records of 100 patients were evaluated. Patients with poor oral intake were fed by EN with tube. A total of 79 patients required nutritional support. Of them, 71 were fed by EN only. Five were fed by EN plus parenteral nutrition (PN),three were fed by PN only. Median duration of EN was 21 days. In the EN only group, 68% gained or maintained their weight. EN should be considered as a feasible option for nutrition support in children undergoing HSCT. Pediatr Blood Cancer 2012; 59: 1327–1329. © 2012 Wiley Periodicals, Inc. 相似文献
28.
29.
Lyme disease is a cause of illness involving multiple organ systems, including, in 10–15 % of cases, the nervous system.
Peripheral radiculoneuritis, cranial neuritis, encephalitis and myelitis are among the neurological manifestations found in
the second and third stages. We present the MRI findings in isolated oculomotor nerve involvement by Lyme disease and discuss
the differential diagnosis.
Received: 14 June 1995 Accepted: 16 January 1996 相似文献
30.
Ozden Kilinc MD Savas Sencan MD Tulay Ercalik MD Pinar Kahraman Koytak MD Hande Alibas MD Osman Hakan Gunduz MD Tulin Tanridag MD Kayihan Uluc MD 《Muscle & nerve》2018,57(1):E24-E28
Introduction: An increased response to painful stimuli without spontaneous pain suggests a role of central hyperexcitability of pain pathways in the pathogenesis of myofascial pain syndrome (MPS). In this study we aimed to test the hypothesis that spinal pain pathways are affected in MPS. We used cutaneous silent period (CSP) parameters to demonstrate the hyperexcitability of spinal pain pathways in MPS. Methods: Twenty‐nine patients diagnosed with MPS and 30 healthy volunteers were included in the study. The CSP recordings were performed in the right upper and left lower extremities. Results: In both upper and lower extremities, patients had prolonged CSP latencies (P = 0.034 and P = 0.049 respectively) and shortened CSP durations (P = 0.009 and P = 0.008, respectively). Discussion: Delayed and shortened CSP in MPS patients implies dysfunction in the inhibitory mechanism of the spinal/supraspinal pain pathways, suggesting central sensitization in the pathogenesis of MPS and supporting our research hypothesis. Muscle Nerve 57 : E24–E28, 2018 相似文献