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排序方式: 共有540条查询结果,搜索用时 12 毫秒
471.
S M Schwartz D R Doody E D Fitzgibbons S Ricks P L Porter C Chen 《Cancer epidemiology, biomarkers & prevention》2001,10(11):1137-1144
Heavy alcohol consumption, particularly in combination with cigarette smoking, increases the risk of oral squamous cell carcinoma (OSCC). Alcohol dehydrogenase 3 (ADH3) converts ethanol to acetaldehyde, which is a suspected oral carcinogen. The ADH3*1 allele is associated with increased conversion of ethanol to acetaldehyde, but whether the risk of OSCC is increased among ADH3*1 carriers, or whether the risk of OSCC attributable to alcohol consumption is modified by ADH3 genotype is unclear from previous studies. We examined the association between ADH3 genotypes, alcohol consumption, and OSCC risk in a population-based study of 333 cases and 541 controls from the state of Washington. The distribution of ADH3 genotypes was similar among cases and controls: ADH3*1/*1: 32.7% cases, 36.5% controls; ADH3*1/*2: 49.0% cases, 43.1% controls: ADH3*2/*2: 18.3% cases, 20.3% controls. The age-, sex-, and race-adjusted odds ratios (OR), relative to ADH3*2/*2 carriers, were as follows: ADH*1/*1: OR, 1.0 [95% confidence interval (CI) = 0.7, 1.5]; and ADH3*1/*2: OR, 1.3 (95% CI = 1.0, 1.8). We modeled the risk of OSCC associated with alcohol consumption as modified by ADH3 genotype adjusting for age, sex, race, and cigarette smoking. Among ADH3*2 homozygotes, the risk of OSCC increased 5.3% (2.1-8.5%) with each additional alcoholic drink/week, compared with 2.5% (1.5-2.6%) and 1.2% (0.0-2.4%) among persons carrying the ADH3*1/*2 and ADH3*1/*1 genotypes, respectively. These data suggest that the ADH3*2 allele confers increased susceptibility to the effect of alcohol on OSCC risk in our population. 相似文献
472.
Pericardial damage is one of the consequences of cardiac radiation and may lead to chronic pericarditis and/or tamponade. In three patients treated with radiation for carcinoma of the left breast, the effusions were loculated on the right side of the pericardium resulting in a peculiar cardiac silhouette. The importance of recognizing this entity and possible treatment is stressed. 相似文献
473.
Vargas-Serrato E Barnwell JW Ingravallo P Perler FB Galinski MR 《Molecular and biochemical parasitology》2002,120(1):41-52
Plasmodium vivax merozoite surface protein-9 (Pvmsp-9) is characterized here along with orthologues from the related simian malarias Plasmodium cynomolgi and Plasmodium knowlesi. We show that although the corresponding MSP-9 proteins do not have acidic-basic repeated amino acid (aa) motifs, they are related to the Plasmodium falciparum acidic-basic repeat antigen (ABRA) also known as p101. Recognition of this new interspecies Plasmodium MSP family stems from the prior identification of related MSP termed PvMSP-185, PcyMSP-150, and PkMSP-110 on the surface of P. vivax, P. cynomolgi and P. knowlesi merozoites. A clone containing the nearly complete P. knowlesi gene encoding PkMSP-110/MSP-9 provided a hybridization probe and initial sequence information for the design of primers to obtain the P. vivax and P. cynomolgi orthologues using polymerase chain reaction (PCR) amplification strategies. The P. vivax, P. cynomolgi and P. knowlesi msp-9 genes encode proteins that range in calculated molecular mass from 80 to 107 kDa, have typical eukaryotic signal peptides and diverse repeated motifs present immediately upstream of their termination codon. Another feature conserved among these proteins, including the P. falciparum ABRA protein, is the positions of four cysteine residues near the N-terminus, suggesting this conservation maintains structural and perhaps functional characteristics in the MSP-9 family. Rabbit polyclonal antisera raised against recombinantly expressed N-termini of P. knowlesi and P. vivax MSP-9 cross-react with the counterpart proteins in immunofluorescence and immunoblot assays. Comparative interspecies investigations of the potential role(s) of Plasmodium MSP-9 in merozoite invasion of erythrocytes and as a malaria vaccine candidate can now be pursued. 相似文献
474.
To assess age-related changes in simple syntactic processing with normal aging, event-related brain potentials (ERPs) elicited by grammatical number violations as individuals read sentences for comprehension were analyzed. Violations were found to elicit a P600 of equal amplitude and latency regardless of an individual's age. Instead, advancing age was associated with a change in the scalp distribution of the P600 effect, being less asymmetric and more frontal (though still with a parietal maximum) in older than younger adults. Our results thus show that the brain's response to simple syntactic violations, unlike those reported for simple binary categorizations and simple semantic violations, is neither slowed nor diminished in amplitude by age. At the same time, the brain's processing of these grammatical number violations did engage at least somewhat different brain regions as a function of age, suggesting a qualitative change rather than any simple quantitative change in speed of processing. 相似文献
475.
Human herpesvirus 8/Kaposi sarcoma herpesvirus cell association during evolution of Kaposi sarcoma 总被引:2,自引:0,他引:2
Pyakurel P Massambu C Castaños-Vélez E Ericsson S Kaaya E Biberfeld P Heiden T 《Journal of acquired immune deficiency syndromes (1999)》2004,36(2):678-683
Kaposi sarcoma (KS) is associated with a herpesvirus (HHV-8/KSHV), which expresses a latency-associated nuclear antigen (LANA). The histopathology of KS is characterized by angiogenesis, inflammatory cells, and the development of CD34+ tumor spindle cells (SCs). However, the cellular basis for the recruitment and dissemination of HHV-8 during the development of KS lesions is not clear. Twenty-nine KS biopsies with AIDS (AKS, n=22) and without HIV infection (endemic KS or EKS, n=7) were immunostained by a triple antibody method to characterize HHV-8-infected and noninfected (LANA+/-) CD34+ SCs, infiltrating CD3+, CD68+, CD20+, and CD45+ leukocytes as well as proliferating (Ki67+) cells. The CD34+/LANA+ SCs were more frequent in late (nodular) as compared with early (patch/plaque) KS stages. However, in late AKS 36.0% of SCs (median of 11 cases) were CD34+/LANA- compared with 20.7% in early cases (median of 11 cases). Furthermore, both AKS and EKS showed, at all stages, a small (4.1-6.5%) population of LANA+/CD34- cells. Proliferating Ki67+ cells were seen (4.5-11.5%) at all KS stages, and were usually more frequent in early AKS, but no significant difference was observed between nodular AKS and EKS. Most of the proliferating cells in the KS lesions were LANA+/CD34+ but a small fraction was LANA+/CD34-. Lesional CD68+ and CD3+ cells varied between AKS (7.3 and 5.2%, respectively) and EKS (4.9 and 3.1%, respectively) but were not clearly stage related. No LANA+ cells were CD3+, CD20+, or CD45+ and very few (<0.5%) were CD68+. These results indicate that not all CD34+ KS SCs were LANA+, suggesting recruitment of noninfected SCs to the lesions. Cell proliferation in general was much higher in early as compared with the late AKS stages. LANA+ SCs could have a proliferative advantage as suggested by higher frequency of cycling (Ki67+) LANA+ SCs. Few macrophages but no lymphocytes are LANA+. 相似文献
476.
477.
478.
479.
Sara Montagnese Esmeralda Balistreri Sami Schiff Michele De Rui Paolo Angeli Giacomo Zanus Umberto Cillo Giancarlo Bombonato Massimo Bolognesi David Sacerdoti Angelo Gatta Carlo Merkel Piero Amodio 《World journal of gastroenterology : WJG》2014,20(42):15756-15762
AIM: To investigate the agreement and prognostic value of different measures of covert hepatic encephalopathy (CHE).METHODS: One-hundred-and-thirty-two cirrhotic outpatients underwent electroencephalography (EEG), paper-and-pencil psychometry (PHES) and critical flicker frequency, scored on the original/modified (CFFo/CFFm) thresholds. Eighty-four patients underwent Doppler-ultrasound to diagnose/exclude portal-systemic shunt. Seventy-nine were followed-up for 11 ± 7 mo in relation to the occurrence of hepatic encephalopathy (HE)-related hospitalisations.RESULTS: On the day of study, 36% had grade I HE, 42% abnormal EEG, 33% abnormal PHES and 31/21% abnormal CFFo/CFFm. Significant associations were observed between combinations of test abnormalities; however, agreement was poor (Cohen’s κ < 0.4). The prevalence of EEG, PHES and CFFo/CFFm abnormalities was significantly higher in patients with grade I overt HE. The prevalence of EEG and CFFm abnormalities was higher in patients with shunt. The prevalence of EEG abnormalities was significantly higher in patients with a history of HE. During follow-up, 10 patients died, 10 were transplanted and 29 had HE-related hospitalisations. Grade I HE (P = 0.004), abnormal EEG (P = 0.008) and abnormal PHES (P = 0.04) at baseline all predicted the subsequent occurrence of HE; CFF did not.CONCLUSION: CHE diagnosis probably requires a combination of clinical, neurophysiological and neuropsychological indices. 相似文献
480.
Effect of sitagliptin on glucose control in type 2 diabetes mellitus after Roux‐en‐Y gastric bypass surgery 下载免费PDF全文
Ankit Shah MD Kiarra Levesque MS Esmeralda Pierini MS Betsy Rojas BS Michael Ahlers MS Sarah Stano BA Marlena Holter BA Roxanne Dutia PhD Scott Belsley MD James McGinty MD Blandine Laferrère MD 《Diabetes, obesity & metabolism》2018,20(4):1018-1023
The present study was a 4‐week randomized trial to assess the efficacy and safety of sitagliptin, a dipeptidyl‐peptidase‐4 inhibitor, in persistent or recurring type 2 diabetes after Roux‐en‐Y gastric bypass surgery (RYGB). Participants (n = 32) completed a mixed meal test (MMT) and self‐monitoring of plasma glucose (SMPG) before and 4 weeks after randomization to either sitagliptin 100 mg daily or placebo daily. Questionnaires were administered to assess gastrointestinal discomfort. Outcome variables were glucose, active glucagon‐like peptide‐1 and β‐cell function during the MMT, and glucose levels during SMPG. Age (56.3 ± 8.2 years), body mass index (34.4 ± 6.7 kg/m2), glycated haemoglobin (7.21 ± 0.77%), diabetes duration (12.9 ± 10.0 years), years since RYGB (5.6 ± 3.3 years) and β‐cell function did not differ between the placebo and sitagliptin groups at pre‐intervention. Sitagliptin was well tolerated, decreased postprandial glucose levels during the MMT (from 8.31 ± 1.92 mmol/L to 7.67 ± 1.59 mmol/L, P = 0.03) and mean SMPG levels, but had no effect on β‐cell function. In patients with diabetes and mild hyperglycemia after RYGB, a short course of sitagliptin provided a small but significant glucose‐lowering effect, with no identified improvement in β‐cell function. 相似文献