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41.
Estrogens are critical hormones involved in reproduction and need to bind to estrogen receptors in target organs for biological activity. Fishes have two distinct estrogen receptor subtypes, alpha (α) and beta (β), with variable combinations of additional isoforms of each subtype dependent on the history of genome duplication within a taxon. The comparative expression patterns of estrogen receptor isoforms during the female reproductive cycle will provide important insights into the unique function and importance of each. The purpose of this study was to measure the mRNAs for the four estrogen receptor isoforms (erα1, erα2, erβ1, erβ2) in the liver and ovary of adult, female rainbow trout over the course of an annual reproductive cycle. The expression of estrogen receptor mRNA isoforms was measured by quantitative real-time RT-PCR. Several reproductive indices (gonadosomatic index, maximum oocyte diameter, plasma estradiol-17β, plasma vitellogenin, and ovulation) were also quantified for comparison and used in a correlation analysis to examine any inter-relationships. Of the four isoforms, the expression of erα1 was highest in the liver, and had a significant positive correlation with liver erβ1 expression. Liver expression of erα2 mRNA was the lowest, but showed a significant positive correlation with maximum oocyte diameter in the ovary. The pattern of the erβ isoforms in liver was one of initially elevated mRNA expression followed by a gradual decrease as reproductive development proceeded. In the ovary the erβ1 isoform had the highest mRNA expression of all estrogen receptor isoforms, at the beginning of the reproductive cycle, but then decreased afterward. Both ovarian erβ isoforms had a significant positive correlation with one another. In contrast, erα2 mRNA expression showed a high maximum level in the ovary near the end of the cycle along with a significant positive correlation with plasma estradiol-17β levels; the highest gonadosomatic indices, maximum oocyte diameter, and vitellogenin levels occurred then too.  相似文献   
42.
Complex karyotype (CK) on metaphase cytogenetics discriminates poor outcome in chronic lymphocytic leukaemia (CLL) patients undergoing salvage treatment; we hypothesized that it might provide prognostic information for patients undergoing allogeneic stem cell transplant. Fifty‐one CLL patients were analysed following transplant; 18‐month overall survival (OS), event‐free survival (EFS) and cumulative incidence of progression estimates were 35%, 14% and 63%, respectively, in patients with CK (n = 19) versus 83%, 68% and 29% in patients without (n = 32) (≤ 0·0001, ≤ 0·0001, and P = 0·02). In patients with high‐risk interphase cytogenetics, CK remained predictive of worse OS (P = 0·02) and EFS (P = 0·009). These findings support further evaluation of metaphase karyotype in transplant risk assessment.  相似文献   
43.
We know that the vast majority of people do not sue after personal injury. There is a significant literature on propensity to sue which relates it partly to the person's view of blame or attribution of responsibility. In many jurisdictions now there is legislation to protect apologies from becoming an admission of legal fault because of the perception that apologies are important to people's functioning. The psychological literature suggests that the psychological role of an apology is closely connected to the attribution of responsibility and that this plays out in a complex way to make apologies effective or ineffective within the psychological or legal context. This article explores how the legal regimes which seek to encourage apologies, (particularly in regimes of compensation for personal injury), have often failed to take account of the lessons that psychology has to offer in making apologies effective both psychologically and in reducing litigation.  相似文献   
44.
Delineating the normal development of brain white matter (WM) over the human lifespan is crucial to improved understanding of underlying WM pathology in neuropsychiatric and neurological conditions. We review the extant literature concerning diffusion tensor imaging studies of brain WM development in healthy individuals available until October 2012, summarise trends of normal development of human brain WM and suggest possible future research directions. Temporally, brain WM maturation follows a curvilinear pattern with an increase in fractional anisotropy (FA) from newborn to adolescence, decelerating in adulthood till a plateau around mid-adulthood, and a more rapid decrease of FA from old age onwards. Spatially, brain WM tracts develop from central to peripheral regions, with evidence of anterior-to-posterior maturation in commissural and projection fibres. The corpus callosum and fornix develop first and decline earlier, whilst fronto-temporal WM tracts like cingulum and uncinate fasciculus have protracted maturation and decline later. Prefrontal WM is most vulnerable with greater age-related FA reduction compared with posterior WM. Future large scale studies adopting longitudinal design will better clarify human brain WM changes over time.  相似文献   
45.

Background

Low socioeconomic status (SES) exacerbates the high rate of smoking relapse in women following childbirth.

Purpose

This study examined multiple models of potential mechanisms linking SES and postpartum smoking relapse among women who quit smoking due to pregnancy.

Methods

Participants were 251 women enrolled in a randomized clinical trial of a new postpartum smoking relapse prevention intervention. Four models of the prepartum mechanisms linking SES and postpartum smoking relapse were evaluated using a latent variable modeling approach.

Results

Each of the hypothesized models were a good fit for the data. As hypothesized, SES indirectly influenced postpartum smoking relapse through increased prepartum negative affect/stress, reduced sense of agency, and increased craving for cigarettes. However, the model that included craving as the sole final pathway between SES and relapse demonstrated superior fit when compared with all other models.

Conclusions

Findings have implications for future interventions that aim to reduce postpartum relapse.  相似文献   
46.
Previous studies suggest overuse disparity of head computed tomography (CT) in white pediatric trauma patients with minor head injuries. Our study is meant to determine if race or insurance status impacts the probability of obtaining head CT in patients with a Glasgow Coma Scale (GCS)?=?15. Using the 2008–2010 National Hospital Ambulatory Medical Care Survey for Emergency Departments (NHAMCS) database, the following variables were analyzed: race, emergency medical services (EMS) arrival, triage category, admission status, gender, age, and insurance status. Patients with injuries were excluded. All patients included had GCS?=?15. In univariate analysis, head CT is more likely to be obtained for patients in the following categories: Medicare insured, private insurance, Medicaid insured, and self-pay, EMS arrival, triage category immediate, and age >75 years. In logistic regression, race (white vs. black) was no longer significant, but there was disparity based on insurance status with privately insured patients more likely to receive a head CT (OR?=?1.683, 95 % CI?=?1.255–2.259). After controlling for the above inclusion variables and focusing on patients less likely to need CT (non-traumatic with GCS?=?15), privately insured patients were more likely to receive a head CT compared with uninsured. Race alone was not associated with an increased probability of receiving a head CT.  相似文献   
47.
48.
Introduction: Generic inhalers are often perceived as inferior to their branded counterparts; however, they are safe and effective if they can meet the regulatory requirements. The approach to assess bioequivalence (BE) in oral dosage form products is not sufficient to address the complexities of inhalational products (e.g., patient-device interface); hence, more considerations are needed and caution should be applied in determining BE of inhaled compounds.

Areas covered: This review outlines the evaluation process for generic inhalers, explores the regulatory approaches in BE assessment, and highlights the considerations and challenges in the current in vitro and in vivo approaches (lung deposition, pharmacokinetic, pharmacodynamic/clinical studies, and patient-device interface) for establishing BE of inhaled compounds.

Expert opinion: The ultimate goals in this field are to establish uniformity in the regulatory approaches to speed the drug submission process in different regions, clear physicians’ misconception of generic inhalers, and have meaningful clinical endpoints such as improvement in patient quality of life when compared to placebo and brand name drugs. As inhalational drugs become more common for other indications such as antibiotics, the technologies developed for inhaled compounds in the treatment of chronic pulmonary diseases may be extrapolated to these other agents.  相似文献   

49.
Nutrition-sensitive agriculture programmes have the potential to improve child nutrition outcomes, but livestock intensification may pose risks related to water, sanitation and hygiene (WASH) conditions. We assessed the impact of SELEVER, a nutrition- and gender-sensitive poultry intervention, with and without added WASH focus, on hygiene practices, morbidity and anthropometric indices of nutrition in children aged 2−4 years in Burkina Faso. A 3-year cluster randomised controlled trial was implemented in 120 villages in 60 communes (districts) supported by the SELEVER project. Communes were randomly assigned using restricted randomisation to one of three groups: (1) SELEVER intervention (n = 446 households); (2) SELEVER plus WASH intervention (n = 432 households); and (3) control without intervention (n = 899 households). The study population included women aged 15−49 years with an index child aged 2−4 years. We assessed the effects 1.5-years (WASH substudy) and 3-years (endline) post-intervention on child morbidity and child anthropometry secondary trial outcomes using mixed effects regression models. Participation in intervention activities was low in the SELEVER groups, ranging from 25% at 1.5 years and 10% at endline. At endline, households in the SELEVER groups had higher caregiver knowledge of WASH-livestock risks (∆ = 0.10, 95% confidence interval [CI] [0.04−0.16]) and were more likely to keep children separated from poultry (∆ = 0.09, 95% CI [0.03−0.15]) than in the control group. No differences were found for other hygiene practices, child morbidity symptoms or anthropometry indicators. Integrating livestock WASH interventions alongside poultry and nutrition interventions can increase knowledge of livestock-related risks and improve livestock-hygiene-related practices, yet may not be sufficient to improve the morbidity and nutritional status of young children.  相似文献   
50.
Similar to several other countries in the world, the epidemiology of hepatitis A virus changed from high to intermediate endemicity level in Tunisia, which led to the occurrence of outbreaks. This study aimed to determine the genetic and antigenic variability of HAV strains circulating in Tunisia during the last few years. Genotyping using complete VP1 gene and VP1-2A junction confirmed the predominance of genotype IA, with co-circulation of several genetic and antigenic variants. Phylogenetic analysis including Tunisian and strains from other regions of the world showed the presence of at least two IA-variants within IA subgenotype. Amino-acid analysis showed several mutations in or close to epitope regions in the VP1-region. This study provides a baseline on the genetic and antigenic variability of HAV circulating strains before the introduction of vaccination into the national immunization schedule.  相似文献   
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