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排序方式: 共有841条查询结果,搜索用时 15 毫秒
781.
Belogubova EV Ulibina YM Suvorova IK Kuligina ESh Karpova MB Shutkin VA Koloskov AV Kuchinskiy AP Togo AV Hanson KP Hirvonen A Imyanitov EN 《Journal of cancer research and clinical oncology》2006,132(5):327-331
Purpose: Polycyclic aromatic hydrocarbons are activated by cytochrome P450 1A1 (CYP1A1) and inactivated by glutathione S-transferase
mu (GSTM1). Therefore, it is expected that a combination of proficient CYP1A1 genotype with deficient GSTM1 variant would result in particularly elevated lung cancer (LC) risk, especially for squamous cell carcinoma (SCC). This study
was aimed to validate whether the CYP1A1-C
3801
(CYP1A1*2) allele has an unfavorable significance alone and/or in combination with the GSTM1 deficiency. Methods: We compared the distribution of CYP1A1 and GSTM1 genotypes in LC patients (n=141), healthy donors (HD, n=204), and elderly tumor-free smokers and non-smokers (ED, n=246). Results: CYP1A1*2 allele carriers demonstrated a clear-cut association with SCC: the adjusted odds ratios (OR) were 2.22 (95% CI=1.06–4.63)
and 2.27 (95% CI=1.14–4.52) when HD and ED were used as referents, respectively. CYP1A1*2(+)/GSTM1(-) combined genotypes were overrepresented in the SCC patients (14/70, 20.0%) and underrepresented in the ED (19/246, 7.7%)
as compared to the intermediate prevalence in the HD (26/204, 12.7%); the adjusted OR for SCC versus ED reached 3.85 (95%
CI=1.43–10.33). Conclusions: In agreement with some literature data, our results support the concerted role of CYP1A1 and GSTM1 at-risk genotypes in SCC predisposition. 相似文献
782.
783.
Victor Pasechnikov Sergej Chukov Evgeny Fedorov Ilze Kikuste Marcis Leja 《World journal of gastroenterology : WJG》2014,20(38):13842-13862
Gastric cancer continues to be an important healthcare problem from a global perspective. Most of the cases in the Western world are diagnosed at late stages when the treatment is largely ineffective. Helicobacter pylori (H. pylori) infection is a well-established carcinogen for gastric cancer. While lifestyle factors are important, the efficacy of interventions in their modification, as in the use of antioxidant supplements, is unconvincing. No organized screening programs can be found outside Asia (Japan and South Korea). Although several screening approaches have been proposed, including indirect atrophy detection by measuring pepsinogen in the circulation, none of them have so far been implemented, and more study data is required to justify any implementation. Mass eradication of H. pylori in high-risk areas tends to be cost-effective, but its adverse effects and resistance remain a concern. Searches for new screening biomarkers, including microRNA and cancer-autoantibody panels, as well as detection of volatile organic compounds in the breath, are in progress. Endoscopy with a proper biopsy follow-up remains the standard for early detection of cancer and related premalignant lesions. At the same time, new advanced high-resolution endoscopic technologies are showing promising results with respect to diagnosing mucosal lesions visually and targeting each biopsy. New histological risk stratifications (classifications), including OLGA and OLGIM, have recently been developed. This review addresses the current means for gastric cancer primary and secondary prevention, the available and emerging methods for screening, and new developments in endoscopic detection of early lesions of the stomach. 相似文献
784.
785.
Stephen B. Asiimwe Robin Fatch Gregory Patts Michael Winter Christine Lloyd-Travaglini Nneka Emenyonu Winnie Muyindike Allen Kekibiina Elena Blokhina Natalia Gnatienko Evgeny Kruptisky Debbie M. Cheng Jeffrey H. Samet Judith A. Hahn 《AIDS and behavior》2017,21(2):204-215
In HIV-infected drinkers, alcohol types more likely to cause inflammation could plausibly increase the risk of HIV disease progression. We therefore assessed the association between alcohol type and plasma HIV RNA level (HIV viral load) among HIV-infected drinkers not on antiretroviral therapy (ART) in Russia and Uganda. We analyzed the data of participants from cohorts in Russia and Uganda and assessed their HIV viral load at enrollment by the alcohol type predominantly consumed. We defined predominant alcohol type as the alcohol type contributing >50% of total alcohol consumption in the 1 month (Russia) or 3 months (Uganda) prior to enrollment. Using multiple linear regression, we compared log10 HIV viral load by predominant alcohol type, controlling for age, gender, socioeconomic status, total number of standard drinks, frequency of drinking ≥6 drinks/occasion, and in Russia, history of injection drug use. Most participants (99.2% of 261 in Russia and 98.9% of 352 in Uganda) predominantly drank one alcohol type. In Russia, we did not find evidence for differences in viral load levels between drinkers of fortified wine (n = 5) or hard liquor (n = 49), compared to drinkers of beer/low-ethanol-content cocktails (n = 163); however, wine/high-ethanol-content cocktail drinkers (n = 42) had higher mean log10 viral load than beer/low-ethanol-content cocktail drinkers (β = 0.38, 95% CI 0.07–0.69; p = 0.02). In Uganda, we did not find evidence for differences in viral load levels between drinkers of locally-brewed beer (n = 41), commercially-distilled spirits (n = 38), or locally-distilled spirits (n = 43), compared to drinkers of commercially-made beer (n = 218); however, wine drinkers (n = 8) had lower mean log10 HIV viral load (β = ?0.65, 95% CI ?1.36 to 0.07, p = 0.08), although this did not reach statistical significance. Among HIV-infected drinkers not yet on ART in Russia and Uganda, we observed an association between the alcohol type predominantly consumed and the HIV viral load level in the Russia sample. These exploratory results suggest that, in addition to total number of drinks and drinking patterns, alcohol type might be a dimension of alcohol use that merits examination in studies of HIV and alcohol related outcomes. 相似文献
786.
Karsten Lunze Dmitry Lioznov Debbie M. Cheng Ruslan V. Nikitin Sharon M. Coleman Carly Bridden Elena Blokhina Evgeny Krupitsky Jeffrey H. Samet 《AIDS and behavior》2017,21(9):2609-2617
Unhealthy alcohol use, highly prevalent in the Russian Federation (Russia), is associated with HIV risk behaviors among people living with HIV (PLWH). HIV stigma contributes to the HIV risk environment in Russia. To examine HIV stigma among Russian PLWH and to explore its association with unhealthy alcohol use, we conducted a longitudinal analysis of 700 PLWH in St. Petersburg, Russia. We assessed the association between alcohol dependence and HIV stigma measured at baseline and 12 months follow-up. Participants with alcohol dependence (n = 446) reported significantly higher HIV stigma scores over time than those without dependence (n = 254) (adjusted mean difference 0.60, 95% CI 0.03–1.17; p = 0.04). In secondary analyses, we examined recent risky alcohol use and did not detect an association with HIV stigma. Alcohol dependence is associated with high HIV stigma among Russian PLWH but the nature of the association is conjectural. HIV prevention efforts in Russia that address alcohol use disorders hold potential to mitigate HIV-related stigma and its possible adverse effects among PLWH. 相似文献
787.
E. Jennifer Edelman Karsten Lunze Debbie M. Cheng Dmitry A. Lioznov Emily Quinn Natalia Gnatienko Carly Bridden Christine E. Chaisson Alexander Y. Walley Evgeny M. Krupitsky Anita Raj Jeffrey H. Samet 《AIDS and behavior》2017,21(9):2618-2627
The link between HIV stigma with substance use is understudied. We characterized individuals with high HIV stigma and examined whether HIV stigma contributes to substance use among HIV-positive Russians reporting risky alcohol use. We analyzed data from HERMITAGE, a randomized controlled trial of 700 people living with HIV/AIDS (PLWHA) with past 6-month risky sex and risky alcohol use in St. Petersburg, Russia (2007–2011). Participants who were female and reported depressive symptoms and lower social support were more likely to endorse high HIV stigma (all p’s < 0.001). In adjusted models, high HIV stigma was not significantly associated with the primary outcome unhealthy substance use and was not consistently associated with secondary substance use outcomes. Interventions to enhance social and mental health support for PLWHA, particularly women, may reduce stigma, though such reductions may not correspond to substantial decreases in substance use among this population. 相似文献
788.
789.
Ryzhikov NN Seneca N Krasikova RN Gomzina NA Shchukin E Fedorova OS Vassiliev DA Gulyás B Hall H Savic I Halldin C 《Nuclear medicine and biology》2005,32(2):109-116
A straightforward method for the preparation of no-carrier-added (n.c.a.) [18F]flumazenil via standard nucleophilic radiofluorination of the corresponding nitro-analog Ro 15-2344 has been developed. The labeling was performed by employing the K18F/kryptofix complex in DMF at 160 degrees C for 30 min and equimolar ratio [K/K2.2.2]+18F-/precursor. Under these conditions, an 18F incorporation rate into flumazenil was in the range of 55-60%. The final product was isolated by HPLC purification within a total synthesis time of 75 min and a radiochemical yield of about 30% (EOB). Human post-mortem whole-hemisphere autoradiography of brain sections demonstrated selective uptake of the radioligand in the areas of high density of the central benzodiazepine receptors (BZR). PET studies in a cynomolgus monkey and metabolite studies by HPLC demonstrated similar results by [18F]flumazenil as for [11C]flumazenil. In blocking experiments, almost all radioactivity was inhibited by the addition of unlabeled flumazenil. [18F]Flumazenil is a suitable radioligand for PET assessment of the BZR. 相似文献
790.
BACKGROUND: 274 children were HIV-infected during 1988-89 in hospitals in the South of Russia during treatment of heavy pathology requiring an intensive therapy and catheterization of large venous vessels. Today only 140 children, receiving HAART now, remain alive. PATIENTS AND METHODS: In 1988 - 89 mothers having nosocomially HIV-infected children were tested on a 'WHOQOL-100' technique (Russian version). FINDINGS: Though the majority of mothers estimated the basic domains of quality of life (QoL) as average and good, the significant part considers their QoL as bad (in physical health, 22.7%, in psychological health, 20.4%, in environment, 25%, in social relationship, 11.4%). The least data of the test were in facets of financial resources, medical and social help and 47.7% consider a general QoL and condition of health as bad, 54.5% marks a lack of positive emotions, and 52.3% had plenty of negative emotions. 45.5% of mothers marked unsatisfactory opportunities for rest and entertainments, 31.8% of those interrogated had problems with an environment of a house. For the most part, mothers considered their health as 'neither bad, nor good' (63.9%), as 'basically bad' (9.1%), and 22.7% as 'basically good'. The basic problems are 'heart problems' (38.6%), 'increased blood pressure' (25%), 'chronic nervous/emotional problems' (36.4%), 'depression' (31.8%). The absence of problems with health was noted by only 9.1% of those surveyed. Overall, 54.5% of mothers considered themselves as patients, and 22.7% as requiring medical treatment 'rather urgently'. At the same time, only 11.4% had received stationary treatment 'in the last 2 weeks', and 15.9%, any out-patient treatment. INTERPRETATION: The problems of QoL and of psychosocial rehabilitation of mothers having nosocomially HIV-infected children are discussed. 相似文献