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Eight normal male volunteers received 80 mg doses of propranolol by the oral and rectal routes and 2.2 mg by intravenous administration in a crossover fashion. Plasma concentrations of propranolol were measured by a gas chromatographic method using an electron capture detector. Individual subject concentration-time data were analysed and results indicated that the data fit a two compartment model with first order absorption. An approximately two-fold higher plasma propranolol concentration was observed after rectal administration as compared with oral dosing. Statistical analysis of the difference in the total AUCs indicates a significantly higher bioavailability of propranolol administered by the rectal route. The reduced bioavailability after oral administration indicates a substantial first pass effect but that it is possible to bypass the liver, at least partially, by giving the drug rectally to man.  相似文献   
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Developing thymocytes are selected for recognition of molecules encoded by the major histocompatibility complex, purged of self-reactive cells and committed to either the CD4 or CD8 lineage. The 1% of thymocytes that complete these tasks emigrate and join the population of peripheral lymphocytes. Whether T cell maturation is complete at the time of thymic exit has been a subject of debate. Using mice transgenic for green fluorescent protein driven by the recombination activating gene 2 promoter to identify recent thymic emigrants, we now show that T cell differentiation continues post-thymically, with progressive maturation of both surface phenotype and immune function. In addition, the relative contribution of CD4 and CD8 recent thymic emigrants was modulated as they entered the peripheral T cell pool. Thus, T cell maturation and subset contribution are both finalized in the lymphoid periphery.  相似文献   
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The COVID-19 pandemic has had a significant impact on populations at an economic, health, and on an interpersonal level, it is still unclear how it has affected health-risk behaviors, such as comfort food consumption over time. This study longitudinally examines the effect of the perceived impact of COVID-19 on comfort food consumption and whether this effect is mediated by emotional distress. A convenience sample of 1048 students and university staff (academic and non-academic) from two universities completed monthly online surveys during the COVID-19 pandemic across six waves (W; W1 to W6). Participants reported their perceived impact of COVID-19 (economic, interpersonal, and health), comfort food consumption, and emotional distress (DASS-21). Using structural equation models, we found an indirect longitudinal effect of the perceived impact of COVID-19 (W1) on comfort food consumption (W3 to W6) through increased emotional distress (W2). The perceived negative impact of COVID-19 on comfort food consumption was fully mediated by the emotional distress during the first waves (W3 and W4), ending in a partial mediation in the last waves (W5 and W6). These findings contribute to disentangling the mechanisms by which the perceived impact of COVID-19 affects comfort food consumption over time, and highlight the role of emotional distress. Future interventions should address comfort food consumption by focusing on handling emotional distress during a crisis.  相似文献   
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Anin vivo glioma model was developed in syngeneic BD IX rats. The BT4An tumor was derived from serialin vivo passages of the BT4A tumor, originally induced from transformed fetal rat brain cells after transplacental exposure to ethylnitrosourea. The cell line was characterized for the presence of neuroglial differentiation markers, chromosome content and cell cycle distribution as determined by flowcytometry. A standardized method for i.c. tumor induction was developed, and the tumors were investigated by light and electron microscopy and for evidence of blood-brain barrier disruption. Tumor cell ability for phagocytosis was studied, as this property may be important for the invasion pattern of the tumors. We conclude that the model seems suitable for bothin vivo therapy and invasion studies. The tumor had 100% tumor take, yielded a predictable symptom-free life span after inoculation, had a characteristic histological picture of an aggressive glioma, and the blood-brain barrier within the tumor was in part disrupted. Compared to the parent cell line, there was loss of neuroglial differentiation markers, the chromosomal distribution was changed, and the ability for phagocytosis was practically lost.  相似文献   
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Longitudinal studies evaluating the relationship between UPF consumption and the incidence of Metabolic Syndrome (MetS) and its components are still scarce. This study aimed to evaluate the effect of UPF consumption on the incidence of MetS and its components in adults. A prospective study was conducted with 896 participants from the 1978/79 Ribeirão Preto cohort, São Paulo, Brazil. UPF consumption was evaluated in %kcal and %g at ages 23–25 years. Incidence of MetS and its components were estimated at ages 37–39 years, according to the Joint Interim Statement criteria. Poisson regression was used to assess associations, and interactions with sex were investigated. UPF consumption had no association with MetS (%kcal Adjusted PR: 1.00; 95% CI: 0.99–1.01; %g Adjusted PR: 1.00; 95% CI: 0.99–1.01). However, women with higher UPF consumption, in %kcal and %g, had a higher risk of abdominal obesity (%kcal: p = 0.030; %g: p = 0.003); and women with higher UPF consumption, in %g, had a higher risk of low HDL-cholesterol (p = 0.041). For the other components of MetS, no significant associations were observed in either sex. These findings suggest evidence of no association between UPF consumption and MetS; however, consumption of UPF was associated with increased WC and low HDL-c, but only in women.  相似文献   
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Introduction:Uterine cervix tumors have an invasive nature, with the capacity to proliferate to surrounding organs such as the vagina, bladder, and rectum, as well as the capacity for dissemination and involvement of structures distant from its place of origin. According to the International Federation of Gynecology and Obstetrics, patients with stages IB I, IB I microscopic (small dimension <4 cm) are indicated for radiotherapy or adjuvant chemoradiotherapy with cisplatin (40 mg/m2). However, cisplatin has side effects such as hematological implications (anemia, neutropenia, and thrombocytopenia), gastrointestinal disorders (nausea, vomiting, diarrhea, constipation), and fatigue. Zingiber officinale contains bioactive compounds that act on pregnancy and postoperative nausea, chemotherapy-induced nausea and vomiting, and also in the management of fatigue, myalgia, and insomnia. This study aimed to evaluate the effects of ginger on chemotherapy-induced nausea and vomiting in patients with cervical cancer undergoing treatment with cisplatin and radiotherapy.Methods and analyses:A randomized intervention clinical and controlled trial with a triple-blind design is described, comparing the effects of institutional antiemetic therapy alone, as well as in combination with 2 different ginger concentrations.Ethics and dissemination:Due to the nature of the study, we obtained approval from the Division Ethics Committee of Liga Contra o Câncer. All participants signed an informed consent form prior to randomization. The results of this study will be published in peer-reviewed journals. The data collected will also be available in a public repository of data.Trial registration number:This study is registered in the Brazilian Registry of Clinical Trials under number RBR-47yx6p9. This study was approved by the Division Ethics Committee of Liga Contra o Câncer under CAAE 40602320.0.0000.5293.  相似文献   
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