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41.
Aging is commonly associated with decreased sleep quality and increased periodic breathing (PB) that can influence heart rate variability (HRV). Cardiac autonomic control, as inferred from HRV analysis, was determined, taking into account the sleep quality and breathing patterns. Two groups of 12 young (21.1 +/- 0.8 years) and 12 older (64.9 +/- 1.9 years) volunteers underwent electroencephalographic, cardiac, and respiratory recordings during one experimental night. Time and frequency domain indices of HRV were calculated in 5-min segments, together with electroencephalographic and respiratory power spectra. In the elderly, large R-R oscillations in the very-low frequency (VLF) range emerged, that reflected the frequency of PB observed in 18% of the sleep time. PB occurred more frequently during rapid eye movement sleep (REM) sleep and caused a significant (P < 0.02) increase in the standard deviation of normal R-R intervals (SDNN) and absolute low-frequency (LF) power. With normal respiratory patterns, SDNN, absolute VLF, LF, and high frequency (HF) power fell during each sleep stage (P < 0.01) compared with young subjects, with no significant sleep-stage dependent variations. An overall decrease (P < 0.01) in normalized HF/(LF + HF) was observed in the elderly, suggesting a predominant loss of parasympathetic activity which may be related to decreased slow-wave sleep duration. These results indicate that two distinct breathing features, implying different levels of autonomic drive to the heart, influence HRV in the elderly during sleep. The breathing pattern must be considered to correctly interpret HRV in the elderly.  相似文献   
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The OPA1 gene, encoding a dynamin-related GTPase that plays a role in mitochondrial biogenesis, is implicated in most cases of autosomal dominant optic atrophy (ADOA). Sixty-nine pathogenic OPA1 mutations have been reported so far. Most of these are truncating mutations located in the GTPase domain coding region (exons 8-16) and at the 3'-end (exons 27-28). We screened 44 patients with typical ADOA using PCR-sequencing. We also tested 20 sporadic cases of bilateral optic atrophy compatible with ADOA. Of the 18 OPA1 mutations found, 14 have never been previously reported. The novel mutations include one nonsense mutation, 3 missense mutations, 6 deletions, one insertion and 3 exon-skipping mutations. Two of these are de novo mutations, which were found in 2 patients with sporadic optic atrophy. The recurrent c.2708_2711delTTAG mutation was found in 2 patients with a severe congenital presentation of the disease. These results suggest that screening for OPA1 gene mutations may be useful for patients with optic atrophy who have no affected relatives, or when the presentation of the disease is atypical as in the case of early onset optic atrophy.  相似文献   
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Recently Merveille and al (1984) using light microscope have observed intranucleolar cavities in rat ovocytes from large antral follicles. They have showed that the frequency of these vacuoles increases when follicular growth is stimulated by gonadotropins. In this paper, the ultrastructure of the nucleolar cavities has been studied. Two types of cavities are visible in these nucleoli: 1. nucleolar "interstices" present at the periphery of the nucleoli in remnants of the granular component and of the dense fibrillar components; 2. nucleolar "vacuoles" which are located in the homogeneous substance forming the greatest part of the nucleolus. The nucleolar vacuoli generally are clear-cut and spherical. The density of their content is similar to the nucleoplasm but they don't communicate to the nucleoplasm. By means of cytochemical to detect Ag-NOR proteins (Ploton and al [1983]) and basic proteins (Sheridan and Barnett [1984]), dense fibrillar component of the nucleolus but no basic proteins may be seen in the wall of the cavity. Moreover no evidence of relation between the presence of the vacuoles and the process of follicular atresia has been found.  相似文献   
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BackgroundGeneral practitioners (GPs) encounter women suffering from premenstrual symptoms. Often women with premenstrual problems experience little understanding from GPs. Views of GPs will influence their approach to these women and their care. Insight into these views is lacking but could help in designing educational programmes for GPs.ObjectivesTo explore the views of Dutch GPs towards aetiology, diagnostic process, and preferred treatment of premenstrual symptoms.MethodsIn 2017, we conducted a qualitative, semi-structured, interview survey among 27 GPs, varying in age, gender, and practice setting.ResultsImportant themes emerged from the interviews: ‘no need for a symptom diary,’ ‘PMS defined as illness’ exclusively in case of disruption of normal functioning, and ‘symptomatic treatment’ as preferred approach. Most GPs considered PMS to be a physiological phenomenon, with taking history as an adequate diagnostic tool. Almost all GPs regarded a normal cyclical hormonal cycle as causal; many also mentioned the combination with personal sensitivity. Some pointed to a dividing line between physiological condition and illness if women could not function normally in daily life. Lastly, the approach GPs preferred was focussing on relieving symptoms of individual patients. In addition to explaining the hormonal cycle and lifestyle advice, all GPs advocated oral contraceptives, and if necessary psychological support. GPs expressed negative feelings about prescribing antidepressants.ConclusionGPs considered physiological changes and personal sensitivity as aetiological factors. We recommend more training to improve GPs knowledge and more insight into the burden of women with PMS. A symptom diary is an essential diagnostic tool for GPs.  相似文献   
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Controlled donation after circulatory death (cDCD) is used for “extended criteria” donors with poorer kidney transplant outcomes. The French cDCD program started in 2015 and is characterized by normothermic regional perfusion, hypothermic machine perfusion, and short cold ischemia time. We compared the outcomes of kidney transplantation from cDCD and brain-dead (DBD) donors, matching cDCD and DBD kidney transplants by propensity scoring for donor and recipient characteristics. The matching process retained 442 of 499 cDCD and 809 of 6185 DBD transplantations. The DGF rate was 20% in cDCD recipients compared with 28% in DBD recipients (adjusted relative risk [aRR], 1.43; 95% confidence interval [CI] 1.12–1.82). When DBD transplants were ranked by cold ischemia time and machine perfusion use and compared with cDCD transplants, the aRR of DGF was higher for DBD transplants without machine perfusion, regardless of the cold ischemia time (aRR with cold ischemia time <18 h, 1.57; 95% CI 1.20–2.03, vs aRR with cold ischemia time ≥18 h, 1.79; 95% CI 1.31–2.44). The 1-year graft survival rate was similar in both groups. Early outcome was better for kidney transplants from cDCD than from matched DBD transplants with this French protocol.  相似文献   
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IntroductionSex differences have already been reported in sub‐Saharan Africa for attrition and immunological response after antiretroviral therapy (ART) initiation, but follow‐up was usually limited to the first two to three years after ART initiation. We evaluated sex differences on the same outcomes in the 10 years following ART initiation in West African adults.MethodsWe used cohort data of patients included in the IeDEA West Africa collaboration, who initiated ART between 2002 and 2014. We modelled no‐follow‐up and 10‐year attrition risks, and immunological response by sex using logistic regression analysis, survival analysis with random effect and linear mixed models respectively.ResultsA total of 71,283 patients (65.8% women) contributed to 310,007 person‐years of follow‐up in 16 clinics in eight West African countries. The cumulative attrition incidence at 10‐year after ART initiation reached 75% and 68% for men and women respectively. Being male was associated with an increased risk of no follow‐up after starting ART (5.1% vs. 4.0%, adjusted Odds Ratio: 1.25 [95% CI: 1.15 to 1.35]) and of 10‐year attrition throughout the 10‐year period following ART initiation: adjusted Hazard Ratios were 1.22 [95% CI: 1.17 to 1.27], 1.08 [95% CI: 1.04 to 1.12] and 1.04 [95% CI: 1.01 to 1.08] during year 1, years 2 to 4 and 5 to 10 respectively. A better immunological response was achieved by women than men: monthly CD4 gain was 30.2 and 28.3 cells/mL in the first four months and 2.6 and 1.9 cells/μL thereafter. Ultimately, women reached the average threshold of 500 CD4 cells/μL in their sixth year of follow‐up, whereas men failed to reach it even at the end of the 10‐year follow‐up period. The proportion of patients reaching the threshold was much higher in women than in men after 10 years since ART initiation (65% vs. 44%).ConclusionsIn West Africa, attrition is unacceptably high in both sexes. Men are more vulnerable than women on both attrition and immunological response to ART in the 10 years following ART initiation. Innovative tracing strategies that are sex‐adapted are needed for patients in care to monitor attrition, detect early high‐risk groups so that they can stay in care with a durably controlled infection.  相似文献   
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