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71.
We tested the hypothesis that MELD-XI values correlated with hepatic total fibrosis scores obtained in 70 predominately stable, post-Fontan patients that underwent elective cardiac catheterization. We found a statistically significant correlation between MELD-XI values and total fibrosis scores (p = 0.003). Thus, serial MELD-XI values may be an additional useful clinical parameter for follow-up care in post-Fontan patients.  相似文献   
72.
It is estimated that 5.9% of all human deaths are attributable to alcohol consumption and that the harmful use of ethanol ranks among the top five risk factors for causing disease, disability, and death worldwide. Ethanol is known to disrupt phospholipid packing and promote membrane hemifusion at lipid bilayers. With the exception of mitochondria involved in hormone synthesis, the sterol content of mitochondrial membranes is low. As membranes that are low in cholesterol have increased membrane fluidity and are the most easily disordered by ethanol, we hypothesize that mitochondria are sensitive targets for ethanol damage. HeLa cells were exposed to 50 mM ethanol and the direct effects of ethanol on cellular ultrastructure were examined utilizing transmission electron microscopy. Our ultramicroscopic analysis revealed that cells exposed to ethanol harbor fewer incidence of apoptotic morphology; however, significant alterations to mitochondria and to nuclei occurred. We observed statistical increases in the amount of irregular cells and cells with multiple nuclei, nuclei harboring indentations, and nuclei with multiple nucleolus-like bodies. Indeed, our analysis revealed that mitochondrial damage is the most extensive type of cellular damage. Rupturing of cristae was the most prominent damage followed by mitochondrial swelling. Ethanol exposure also resulted in increased amounts of mitochondrial rupturing, organelles with linked membranes, and mitochondria localizing to indentations of nuclear membranes. We theorize that these alterations could contribute to cellular defects in oxidative phosphorylation and, by extension, the inability to generate regular levels of cellular adenosine triphosphate.  相似文献   
73.
Intermittent fasting (IF) reportedly increases resistance and intestinal IgA response to Salmonella typhimurium infection in mature mice. The aim of this study was to explore the effect of aging on the aforementioned improved immune response found with IF. Middle-aged male BALB/c mice were submitted to IF or ad libitum (AL) feeding for 40 weeks and then orally infected with S. typhimurium. Thereafter, infected animals were all fed AL (to maximize their viability) until sacrifice on day 7 or 14 post-infection. We evaluated body weight, bacterial load (in feces, Peyer’s patches, spleen and liver), total and specific intestinal IgA, lamina propria IgA+ plasma cells, plasma corticosterone, and messenger RNA (mRNA) expression of α-chain, J-chain, and the polymeric immunoglobulin receptor (pIgR) in liver and intestinal mucosa. In comparison with the infected AL counterpart, the infected IF group (long-term IF followed by post-infection AL feeding) generally had lower intestinal and systemic bacterial loads as well as higher total IgA on both post-infection days. Both infected groups showed no differences in corticosterone levels, body weight, or food and caloric intake. The increase in intestinal IgA was associated with enhanced pIgR mRNA expression in the intestine (day 7) and liver. Thus, to maintain body weight and caloric intake, IF elicited metabolic signals that possibly induced the increased hepatic and intestinal pIgR mRNA expression found. The increase in IgA probably resulted from intestinal IgA transcytosis via pIgR. This IgA response along with phagocyte-induced killing of bacteria in systemic organs (not measured) may explain the resolution of the S. typhimurium infection.  相似文献   
74.
The main purpose of the present study was to examine the effects of a physical education-based stretching development and maintenance program on hamstring extensibility in schoolchildren. A sample of 150 schoolchildren aged 7-10 years old from a primary school participated in the present study (140 participants were finally included). The six classes balanced by grade were cluster randomly assigned to the experimental group 1 (n = 51), experimental group 2 (n = 51) or control group (n = 49) (i.e., a cluster randomized controlled trial design was used). During the physical education classes, the students from the experimental groups 1 and 2 performed a four-minute stretching program twice a week for nine weeks (first semester). Then, after a five-week period of detraining coinciding with the Christmas holidays, the students from the experimental groups 1 and 2 completed another stretching program twice a week for eleven weeks (second semester). The students from the experimental group 1 continued performing the stretching program for four minutes while those from the experimental group 2 completed a flexibility maintenance program for only one minute. The results of the two-way analysis of variance showed that the physical education-based stretching development program significantly improved the students’ hamstring extensibility (p < 0.001), as well as that these gains obtained remained after the stretching maintenance program (p < 0.001). Additionally, statistically significant differences between the two experimental groups were not found (p > 0.05). After a short-term stretching development program, a physical education-based stretching maintenance program of only one-minute sessions twice a week is effective in maintaining hamstring extensibility among schoolchildren. This knowledge could help and guide teachers to design programs that allow a feasible and effective development and maintenance of students’ flexibility in the physical education setting.

Key points

  • A physical education-based stretching maintenance program of only one-minute sessions twice a week is effective in maintaining hamstring extensibility among schoolchildren.
  • A four-minute maintenance program shows similar effects that the one-minute maintenance program on hamstring extensibility among schoolchildren.
  • Physical education teachers and other practitioners could carry out one-minute programs for a feasible and effective maintenance of students’ flexibility.
Key words: Flexibility program, flexibility maintaining, classic sit-and-reach test, physical fitness, primary school children, physical education setting  相似文献   
75.
BACKGROUND: [corrected] The Attention Deficit Disorder with Hyperactivity (ADDH) Barkley model predicts concomitant deficits in working memory and in the development of a sense of time as a consequence of poor behavioral inhibition. Objective: To evaluate electrophysiologically Barkley's theory (1997). SUBJECTS AND METHODS: We studied the electroencephalogram (EEG) of fifteen right-handed, normal limit IQ ADDH children (inattentive subtype), aged 7-11 years, and a control group. Subjects were studied at rest, with the eyes open (RO) while performing a time estimation task (ET). Forty-two data matrices were analyzed in three conditions: RO, ET and ET-RO, to assess broad-band spectral parameters; the anteriority, temporal-referenced and laterality quotients (Aq, Aqt and Lq, respectively); and the theta/alpha and theta/beta ratios. RESULTS: Analyses of variance revealed significant differences for ES-RA, in absolute (Aq &Aqt) and relative powers (Aq). Discriminant function analysis was able to predict group membership with an accuracy over 80%, but it decreased slightly when the leave-one-out method was applied Linear discrimination based on right hemisphere Aqt values showed the highest discrimination accuracy. CONCLUSIONS: These results support Barkley's theory, suggesting further evaluation of the temporal-referenced anteriority quotient as a promising electrophysiological tool for the diagnosis and follow up of ADDH children.  相似文献   
76.
INTRODUCTION: The transplantation program of organs obtained from deceased donors requires a complex structural organization. Medical, logistic, and cultural aspects must be taken into account. MATERIAL AND METHODS: We analyzed the detection of possible organ donors in San Luis Potosí, Mexico, from August 21, 1999 to August 30, 2002. We studied the main causes of brain death, donor conversion, legal implications, reasons for donation and refusal to donate. RESULTS: 71.42% of donors and 64.15% of non donors required legal intervention. The main cause of brain death was brain traumatic injury (66.97%). The donation rate per one million inhabitants was 8.3. CONCLUSIONS: Adequate forensic management has a positive influence on achieved deceased donors. An effective team work and coordination with the State Council of Transplants has allowed the State of San Luis Potosí to have the highest rate of organ donation in Mexico.  相似文献   
77.
This study sheds light on the smoking pregnant women's outlook on cigarette use. The Theory of Social Representations was used as a theoretical reference. For data analysis, the Collective Subject Discourse was constructed. Of the 27 women that were interviewed, 18 had finished elementary education, 8 had completed secondary education, and one had college level education; 14 had a stable union and 6 were married. Four themes emerged from the interviews: (1) starting to smoke: a natural, social practice; (2) satisfaction versus guilt; (3) shattering news: effects of smoking on pregnancy; and (4) quitting: between will and ability. Pregnant women revealed negative ideas about smoking, considering smoking the worst of addictions and a potential cause for complications to the fetus and the mother. Smoking was represented in a prejudicial manner, disregarding the existence of treatment and the need for it. Emerging difficulties were related to quitting, for which professionals, information and adequate approaches for treatment and support for achieving success are utmost necessities.  相似文献   
78.
The aim of this study was to evaluate the oral sequelae of radiotherapy in patients treated between 1999 and 2003 for head and neck tumors. One-hundred patients (24 women, 76 men) ranging in age from 30 to 83 years (mean 59.2 years) were examined. Time since radiotherapy ranged from 1 to 72 months (mean 28 months). The total mean radiation dose received by the patients was 5,955 cGy. The evaluation protocol included anamnesis, intraoral and extraoral examination, measurement of stimulated salivary flow and salivary pH. Symptoms reported by the patients included dry mouth (68%), dysphagia (38%), and dysgeusia (30%). In 64% of the patients, the mean stimulated salivary flow rate was less than 0.7 ml/min. The mean salivary pH was 6.97 (+/- 0.714). Stimulated salivary flow increased with increasing postradiotherapy time (p < 0.05). The prevalence of mucositis was associated with higher radiation doses (p < 0.05), and the prevalence of atrophic candidiasis was related to a longer post-treatment period (p < 0.05). Two cases of recurrence of the primary tumor were detected during the study. The main effect of radiotheraphy in the head and neck region was a reduction of the salivary flow rate, even though our study demonstrated that there was a modest late improvement of the salivary flow.  相似文献   
79.
Regional odontodysplasia (RO), also known as ghost teeth, is an unusual nonhereditary developmental anomaly of tooth formation that characteristically affects enamel and dentin formation of the primary and/or permanent dentition. In the present paper, we report a case of RO affecting a 7-year-old boy, with 9 years of follow-up. During this time, progressive development of dental tissue was observed, including complete root formation. However, delayed dental eruption was evident. In view of these findings, we discuss the clinical presentation, pathogenesis, differential diagnosis, and treatment of RO.  相似文献   
80.
BACKGROUND: The primary treatment for attention-deficit/hyperactivity disorder (ADHD) has been psychostimulants. Recently developed nonpsychostimulant treatments have allowed certain patients to switch from a psychostimulant to a nonpsychostimulant. However, the outcomes of such switches have not been systematically studied. OBJECTIVE: The purpose of this pilot study was to assess treatment tolerance and efficacy during a cross-taper transition from methylphenidate or amphetamine to atomoxetine among children and adolescents with ADHD. METHODS: This pilot study was conducted in patients (aged 6-17 years) with incomplete responses (failure to obtain full reduction/elimination of symptoms) or intolerance of adverse events (AEs) during psychostimulant treatment. Patients continued ongoing psychostimulant treatment during the first week of the study. Transition to atomoxetine began by administering atomoxetine 0.5 mg/kg . d plus full-dose psychostimulant for 1 week, followed in the second week by 1.2 mg/kg . d atomoxetine plus half-dose psychostimulant. Patients remained on 1.2 mg/kg . d atomoxetine monotherapy for the remaining 5 weeks. This stepwise transition was enacted due to the difference in pharmacodynamics between the psychostimulants and atomoxetine. Applying a stepwise cross-titration allowed for better control of ADHD symptoms during the intervening period. Change in ADHD symptoms, as measured by the mean change in the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-administered and -scored (ADHDRS-IV-Parent:Inv), was assessed from baseline to end point. RESULTS: Of the 62 subjects enrolled in the study, 39 (62.9%) were diagnosed as ADHD-combined type. Similar proportions were receiving methylphenidate (51.6%) and amphetamine (48.4%). Slightly more wished to switch due to inadequate response (53.2%) than intolerability (46.8%). Nine subjects discontinued at various times during the course of the study (patient or parent/caregiver decision [4], AE [2], protocol violation [2], and lack of efficacy [1]). Mean (SD) ADHDRS-IV-Parent:Inv total scores (n = 59, last-observation-carried-forward) improved significantly from baseline (visit 2) to an end point (32.1 [10.5] vs 22.6 [14.0]; P < 0.001). Of the 58 subjects answering in the atomoxetine monotherapy phase, 38 (65.5%) reported a preference for atomoxetine treatment over their previous psychostimulant. Tolerability results were as follows: 26 (44.1%) of 59 patients reported >or=1 AE, the most common being somnolence (4 [6.8%]), fatigue (3 [5.1%]), decreased appetite (3 [5.1%]), cough (3 [5.1%]), headache (3 [5.1%]), and contact dermatitis (2 [3.4%]). No clinically severe AEs were reported. Both mean (SD) diastolic (2.4 [7.8] mm Hg; P = 0.031) and systolic (2.4 [7.9] mm Hg; P = 0.029) blood pressures increased significantly from baseline to end point. Electrocardiography revealed a significant increase in mean (SD) heart rate (9.2 [11.6] bpm; P < 0.001) and a corresponding decrease in mean (SD) RR interval (-77.8 [98.2] ms; P < 0.001). Statistically significant, but mild, increases in diastolic pressure and heart rate were observed. CONCLUSION: These children and adolescent patients were successfully switched from methylphenidate or amphetamine to atomoxetine treatment, with resulting improvement in ADHD symptom severity from baseline in this pilot study.  相似文献   
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