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排序方式: 共有1125条查询结果,搜索用时 15 毫秒
21.
Increased aneusomy and long arm deletion of chromosomes 5 and 7 in the lymphocytes of Chinese workers exposed to benzene 总被引:4,自引:1,他引:4
Zhang L; Rothman N; Wang Y; Hayes RB; Li G; Dosemeci M; Yin S; Kolachana P; Titenko-Holland N; Smith MT 《Carcinogenesis》1998,19(11):1955-1961
Two of the most common cytogenetic changes in therapy- and chemical-
related leukemia are the loss and long (q) arm deletion of chromosomes 5
and 7. The detection of these aberrations in lymphocytes of individuals
exposed to potential leukemogens may serve as useful biomarkers of
increased leukemia risk. We have used a novel fluorescence in situ
hybridization (FISH) procedure to determine if specific aberrations in
chromosomes 1, 5 and 7 occur at an elevated rate in the blood cells of
workers exposed to benzene. Forty-three healthy workers exposed to a wide
range of benzene concentrations (median 31 p.p.m., 8 h time-weighted
average) and 44 unexposed controls from Shanghai were studied. Whole blood
was cultured and metaphase spreads were harvested at 72 h. Benzene exposure
was associated with increases in the rates of monosomy 5 and 7 but not
monosomy 1 (P < 0.001, P < 0.0001 and P = 0.94, respectively) and
with increases in trisomy and tetrasomy frequencies of all three
chromosomes. Long arm deletion of chromosomes 5 and 7 was increased in a
dose-dependent fashion (P = 0.014 and P < 0.0001) up to 3.5-fold in the
exposed workers. These results demonstrate that leukemia-specific changes
in chromosomes 5 and 7 can be detected by FISH in the peripheral blood of
otherwise healthy benzene-exposed workers. We suggest that aberrations in
chromosomes 5 and 7 may be useful biomarkers of early biological effect for
benzene exposure.
相似文献
22.
G. Halverson BS MT E. Shanahan I. Santiago R. Mabile T. Thurrell A. M. Strupp C. F. W. Wolf P. Spruell and M. K. Moulds 《Vox sanguinis》1994,66(3):206-209
The antibodies of the Dombrock blood group system have only rarely been encountered in transfusion practice, and anti-Dob has not previously been implicated in an acute hemolytic transfusion reaction. We have encountered the first such case involving a chronically transfused black female with hemoglobin SS disease and multiple antibodies in her serum. During a previous admission for sickle cell crisis, the patient received 3 units of compatible blood with no untoward effects. Serum obtained 21 days later contained, in addition to the known antibodies, anti-S plus an unidentified antibody showing characteristics of HTLA. Blood lacking the E, K1, Fy(a), Jk(b) and S antigens was obtained, and 2 least incompatible units were transfused. While administering the second unit, the patient complained of fever and low back pain, and hemoglobinemia was detected. Anti-Dob was identified in the post-reaction samples by absorption-elution tests, and the patient was confirmed to be Do(a+b–). The first unit transfused during this hemolytic episode tested Do (b+). This case, and a similar case involving anti-Doa reported in 1986, strengthens the belief that Dombrock antibodies are clinically significant and illustrates the need for their differentiation, prior to transfusion from less clinically significant HTLA antibodies. 相似文献
23.
T. Lin E.P. Murono J. Osterman H.R. Nankin 《Metabolism: clinical and experimental》1981,30(2):156-159
The effects of tamoxifen on rat testicular steroidogenesis were studied using dispersed interstitial cells. Tamoxifen significantly inhibited LH-, and 8-bromo-adenosine 3′,5′-monophosphate (8-bromo-cyclic AMP)-stimulated testosterone synthesis in a dose-dependent manner. Tamoxifen (10?5M) also reduced LH-stimulated cyclic AMP formation. The addition of equimolar concentrations of 17β-estradiol or tamoxifen separately to interstitial cells resulted in similar inhibition of LH-stimulated testosterone synthesis. When equimolar concentrations of 17β-estradiol and tamoxifen were added concomitantly to interstitial cells, the inhibition was additive. Present studies demonstrate that tamoxifen has direct inhibitory effects on testicular steroidogenesis: both at the plasma membrane resulting in decreased cyclic AMP formation and also at steps subsequent to cyclic AMP. 相似文献
24.
Dr. Michael D. Schuffler MD Lawrence R. Kaplan MD Linda Johnson BS MT ASCP 《Digestive diseases and sciences》1978,23(9):821-828
The purpose of this investigation was to determine the frequency and severity of small intestinal mucosal damage in pseudoobstruction syndromes. One hundred eighty-nine interpretable biopsies from 12 patients were blindly reviewed by two investigatiors. The underlying disorders were scleroderma in 7 and idiopathic intestinal pseudoobstruction in 5. All 12 had small-intestinal dilatation on small-bowel series. Eight of the 12 patients had biopsies characterized by moderate, to severe mucosal damage; 3 of these had some biopsies which were flat. The damage did not correlate with: (1) types and numbers of organisms recovered from small intestinal aspirates; (2) duration of illness; (3) degree of dilatation of the proximal small bowel; (4) concentrations of deconjugated bile salts in small intestinal fluid; or (5) amount of fat absorbed in fat-balance studies. We conclude that mucosal damage is common in pseudoobstruction syndromes. The pathogenesis of the damage and its relationship to intraluminal bacteria remain undefined. 相似文献
25.
The finding of elevated intracellular levels of adenosine deaminase (ADA) in some patients with acute lymphoblastic leukemia has led to attempts to control this disease with the adenosine deaminase inhibitor 2'-deoxycoformycin (dCF). Because of clinical reports indicating its relative freedom from myelotoxicity, we have tested the effects of this drug on erythroid, granulocytic, and T-lymphocyte colony formation by normal marrow and peripheral blood cells. While clinically the drug has been found to be active at serum concentrations of approximately 10 microM, we have tested it at concentrations up to and including 1 mM. It was found that both erythroid and granulocytic colony growth was completely unaffected by 1 mM dCF, a concentration at least 2 magnitudes higher than that necessary to totally ablate intracellular ADA levels. T-lymphocyte colony growth was unaffected by 100 microM dCF, but at 1 mM some inhibition was observed. These findings therefore indicate that dCF, while able to cause leukemic cell lysis in vivo, has no inhibitory effect on the proliferative capacity of normal hematopoietic cells. 相似文献
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29.
Forde KA Haynes K Troxel AB Trooskin S Osterman MT Kimmel SE Lewis JD Lo Re V 《Journal of viral hepatitis》2012,19(4):271-277
Hepatitis C virus (HCV) infection is associated with systemic inflammation and metabolic complications that might predispose patients to atherosclerosis. However, it remains unclear if HCV infection increases the risk of acute myocardial infarction (MI). To determine whether HCV infection is an independent risk factor for acute MI among adults followed in general practices in the United Kingdom (UK), a retrospective cohort study was conducted in The Health Improvement Network, from 1996 through 2008. Patients ≥18 years of age with at least 6 months of follow-up and without a prior history of MI were eligible for study inclusion. HCV-infected individuals, identified with previously validated HCV diagnostic codes (n = 4809), were matched on age, sex and practice with up to 15 randomly selected patients without HCV (n = 71 668). Rates of incident MI among patients with and without a diagnosis of HCV infection were calculated. Adjusted hazard ratios were estimated using Cox proportional hazards regression, controlling for established cardiovascular risk factors. During a median follow-up of 3.2 years, there was no difference in the incidence rates of MI between HCV-infected and -uninfected patients (1.02 vs 0.92 events per 1000 person-years; P = 0.7). HCV infection was not associated with an increased risk of incident MI (adjusted HR, 1.10; 95% confidence interval [CI], 0.67-1.83). Sensitivity analyses including the exploration of a composite outcome of acute MI and coronary interventions yielded similar results (adjusted HR, 1.16; 95% CI, 0.77-1.74). In conclusion, HCV infection was not associated with an increased risk of incident MI. 相似文献
30.