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Abdullahi Idris Nasir Lozano Carmen Juárez-Fernández Guillermo Höfle Ursula Simón Carmen Rueda Silvia Martínez Angela Álvarez-Martínez Sandra Eguizábal Paula Martínez-Cámara Beatriz Zarazaga Myriam Torres Carmen 《European journal of clinical microbiology & infectious diseases》2023,42(5):569-581
European Journal of Clinical Microbiology & Infectious Diseases - This study determined the carriage rates and antimicrobial resistance (AMR) genes of enterococci from... 相似文献
13.
Myriam Khlat Marie-Hélène Cazes Emmanuelle Génin Marguerite Guiguet 《Cancer epidemiology, biomarkers & prevention》2004,13(10):1660-1664
Case-control studies of genetic factors are prone to a special form of confounding called population stratification, whenever the existence of one or more subpopulations may lead to a false association, be it positive or negative. We quantify both the bias (in terms of confounding risk ratio) and the probability of false association (type I error) in the most unfavorable situation in which only one high-risk subpopulation is hidden within the studied population, considering different scenarios of population structuring and varying sample sizes. In accord with previous work, we find that the bias is likely to be small in most cases. In addition, we show that the same applies to the associated type I error whenever the subpopulation is small in proportion. For instance, when the hidden subpopulation makes up 5% of the entire population, with an allelic frequency of 0.25 (versus 0.10) and a disease rate that is double, then the estimated bias is 1.07 and the type I error associated with a sample of 500 cases and 500 controls is 8% (instead of 5%). We also show that the type I error is substantially greater for a rare allele (frequency of 0.1) than for a common allele (frequency of 0.5) and analyze the pattern of increase of vulnerability to stratification bias with sample size. Based on our findings, we may therefore conclude that with moderate sample sizes the type I error associated with population stratification remains very limited in most realistic scenarios. 相似文献
14.
Claire Joqueviel Véronique Gilard Robert Martino Myriam Malet-Martino Ulf Niemeyer 《Cancer chemotherapy and pharmacology》1997,40(5):391-399
Phosphorus-31 nuclear magnetic resonance spectroscopy was used to evaluate the stability of carboxycyclophosphamide (CXCP)
and carboxyifosfamide (CXIF) in human urine at pH 7.0 and 5.5 at 25°, 8°, −20°, and −80 °C. At 25 °C and pH 7.0, CXCP and
CXIF are relatively stable (≈10% degradation in 24 h). In contrast, they are much less stable at pH 5.5 (≈80% degradation
of CXIF and ≈50% degradation of CXCP in 24 h). The rate of degradation of CXCP and CXIF was a function of the storage temperature
of the urine samples but, even at −80 °C, was not negligible: ≈30% degradation for CXCP irrespective of pH and ≈40% and 50%
degradation for CXIF at pH 7.0 and 5.5, respectively, after storage for 6 months. CXCP was more stable than CXIF at either
pH (7.0 or 5.5) and at all storage temperatures (8°, −20°, or −80 °C) of the urine samples. CXCP and CXIF were more stable
at pH 7.0 than at pH 5.5, although this difference fell with decreasing temperatures to be almost negligible at −80 °C. To
ensure a true estimate of CXCP and CXIF levels, urine samples must be frozen and stored at −80 °C within a few hours of micturition.
CXCP and CXIF assays should also be carried out within 2 months and 1 month of storage, respectively.
Received: 13 July 1996 / Accepted: 20 January 1997 相似文献
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Olivier Rouvière Philippe Puech Raphaële Renard-Penna Michel Claudon Catherine Roy Florence Mège-Lechevallier Myriam Decaussin-Petrucci Marine Dubreuil-Chambardel Laurent Magaud Laurent Remontet Alain Ruffion Marc Colombel Sébastien Crouzet Anne-Marie Schott Laurent Lemaitre Muriel Rabilloud Nicolas Grenier 《The lancet oncology》2019,20(1):100-109
17.
Ricard Navins Giovanni Oriolo Igor Horrillo Myriam Cavero Bruno Aouizerate Martin Schaefer Lucile Capuron J Javier Meana Rocio Martin-Santos 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2022,25(6):468
BackgroundThe relationship between antidepressant response and glial, inflammatory, and metabolic markers is poorly understood in depression. This study assessed the ability of biological markers to predict antidepressant response in major depressive disorder (MDD).MethodsWe included 31 MDD outpatients treated with escitalopram or sertraline for 8 consecutive weeks. The Montgomery-Åsberg Depression Rating Scale (MADRS) was administered at baseline and at week 4 and 8 of treatment. Concomitantly, blood samples were collected for the determination of serum S100B, C-reactive protein (CRP), and high-density lipoprotein cholesterol (HDL)-C levels. Treatment response was defined as ≥50% improvement in the MADRS score from baseline to either week 4 or 8. Variables associated with treatment response were included in a linear regression model as predictors of treatment response.ResultsTwenty-seven patients (87%) completed 8 weeks of treatment; 74% and 63% were responders at week 4 and 8, respectively. High S100B and low HDL-C levels at baseline were associated with better treatment response at both time points. Low CRP levels were correlated with better response at week 4. Multivariate analysis showed that high baseline S100B levels and low baseline HDL-C levels were good predictors of treatment response at week 4 (R2 = 0.457, P = .001), while S100B was at week 8 (R2 = 0.239, P = .011). Importantly, baseline S100B and HDL-C levels were not associated with depression severity and did not change over time with clinical improvement.ConclusionsSerum S100B levels appear to be a useful biomarker of antidepressant response in MDD even when considering inflammatory and metabolic markers. 相似文献
18.
This study investigates the relation between early life conditions and adult obesity in France, using a rich data set collected through the 2003 nationally representative Life History Survey. No salient factor emerged in men, while in women, after controlling for current socio-demographic characteristics, a relation was found between obesity and the following factors: father's occupation (OR = 3.2 for women whose father was a clerical worker, versus those whose father was in a higher-level occupation); experience of economic hardship in childhood (OR = 2.0), and; high parity (OR = 2.1 for parities of more than 3 versus parity of 1). Neither early family history nor mother's working status surfaced as significant factors. Those findings highlight a definite gender pattern, with a strong association between early disadvantage and obesity in women, but not in men. Potential mechanisms are discussed, particularly the “habitus”, the “thrifty phenotype” and the “feast–famine” hypotheses, and possible interactions with childbearing and motherhood. An integration of social and biological perspectives is needed to reach a better understanding of the processes involved, and to achieve progress in primary and secondary prevention. 相似文献
19.
Legleye S Beck F Khlat M Peretti-Watel P Chau N 《The Journal of adolescent health》2012,50(4):395-402
PurposeTo investigate the influence of the family socioeconomic status (F-SES) on various intensities and frequencies of cannabis use in late adolescence.Design/Settings/ParticipantsData were obtained from a cross-sectional survey conducted in 2008, which was representative of French youth aged 17(n = 39,542). Outcomes were overall use (abstinence, lifetime use, 1–9, and 10+ uses in the past year) for all adolescents, and frequent use for those who smoked cannabis at least 10 times in the past year (≤9, 10–19, 20+ uses in the past month). Additionally, cannabis use disorders and heavy use (having smoked at least 4 joints last time) were studied among previous-year users. F-SES was the highest occupational category of both parents (in 7 categories, from managers/professionals [used as the reference category] to inactive/unemployed). Multinomial logistic regressions were computed controlling for gender; other substances use; parental separation; parental use of alcohol, tobacco, and cannabis; housing, being out of school, and sociability.FindingsFor overall use, we found a strong positive social gradient: the lower the F-SES or the higher the frequency of use, the lower the odds ratio (OR) (from .85 to .52 for 10+ uses in the past year among farmers). For frequent use, we found a strong negative gradient: the lower the F-SES category, the higher the OR (from 1.02 to 2.05 among inactive/unemployed), and likewise for cannabis use disorder and heavy use (OR = 1.85 and 2.03 among inactive/unemployed).ConclusionsAdolescents from affluent families are more prone to experimentation with cannabis and to use it at low levels but present lower levels of frequent, heavy, or problematic use than those from other SES categories. Mechanisms that hinder transition to intensive use should be investigated. 相似文献
20.
BACKGROUND: The management of symptomatic cholelithiasis during pregnancy remains controversial. We compared outcomes after medical versus surgical management of biliary tract disease in pregnant patients. METHODS: We reviewed the clinical course of patients with symptomatic cholelithiasis during pregnancy from 1992 to 2002 at two university hospitals. RESULTS: Seventy-six women with 78 pregnancies were admitted with biliary tract disease. Of the 63 women who presented with symptomatic cholelithiasis, 10 underwent surgery while pregnant. There were no deaths, preterm deliveries, or intensive care unit admissions. Fifty-three patients were treated medically. Their clinical courses were complicated by symptomatic relapse in 20 patients (38%), by labor induction to control biliary colic (8 patients), and by premature delivery in 2 patients. Each relapse in the medically managed group accounted for an additional five days in hospital. CONCLUSION: Surgical management of symptomatic cholelithiasis in pregnancy is safe, decreases days in hospital, and reduces the rate of labor induction and preterm deliveries. 相似文献