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141.
AIDS and Behavior - The World Health Organization identified men as an essential group to target with HIV testing and treatment strategies;: men who have sex with men (MSM) and male clients of...  相似文献   
142.
Experimental bacteremia and hepatic nutrient blood flow   总被引:1,自引:0,他引:1  
To study altered hepatic nutrient blood flow during the early phases of bacteremia, Sprague-Dawley rats (250-350 gm) underwent carotid cannulation; 24 hr later, they received an intravascular infusion of 2.5 X 10(8) Escherichia coli (LD70) over 45 min. Controls were anesthetized and cannulated only. Experimental and control animals then received a flow-dependent dose of indocyanine green (5 mg/kg) via the cannula, and arterial blood was sampled at 3, 4, 5, 6, 7, and 8 min after. Separate groups of animals were studied at 3 and 6 hr after bacteremia. The half-life (t1/2) of indocyanine green clearance was then determined at each time period, with t1/2 representing an estimation of total hepatic nutrient blood flow. Results indicated a prolonged t1/2 at both time periods in the bacteremic rats. Hepatic histology from plastic-embedded sections appeared to reveal fibrin, platelets, and leukocyte fragments within the sinusoids. From these data, we conclude that reduced nutrient blood flow occurs during experimental bacteremia prior to systemic changes of arterial pressure.  相似文献   
143.
Experiments were undertaken to assess the role of amifostine in the activation of latent TGFbeta1 and in the smad proteins cascade (smad 2/3, smad4, smad7), focusing on megakaryocytes, in the bone marrow irradiated in vivo. Non-irradiated megakaryocytes were negative for active TGFbeta1. Immunopositivity to active TGFbeta1 was detected in megakaryocytes 10 days after irradiation in amifostine- treated and untreated marrows. Smad 2/3 and smad 4 were strongly positive in the nucleus of megakaryocytes 10 days after irradiation. At the same time, a predominant hypocellular bone marrow with foci of hematopoiesis was observed with few megakaryocytes. An increase in the number of reticulin fibers was also seen. In amifostine-treated marrows, smad 2/3 and smad4 were not detected in the nucleus but were positive in the cytoplasm of megakaryocytes 10 days after irradiation. Coincidentally, bone marrows were cellular with megakaryocytes. Smad7 immunoexpression was detected in the cytoplasm of megakaryocytes in the non-irradiated, amifostine-treated and in the irradiated, amifostine-treated marrows. Data indicate that amifostine does not prevent latent TGFbeta1 activation in irradiated megakaryocytes. While TGFbeta1 signal transduction occurs in megakaryocytes in untreated bone marrows, it is inhibited in megakaryocytes in amifostine-treated marrows due to the induction of smad 7 activation. This is the first report showing smad 7 activation by amifostine. Our results also suggest a role for TGFbeta1 as an inhibitor of megakaryocytes in vivo.  相似文献   
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Patients with a large congenital atrial septal defect (ASD) traditionally have the ASD repaired at the preschool age. Unfortunately, insufficient education of patients regarding medical science and clinical recommendations can lead to delayed therapy, resulting in complications during adulthood. We report a rare case of a large congenital ASD in a 20-year-old man. Echocardiography showed a 67-mm ostium secundum defect and moderate mitral and tricuspid regurgitation. The patient underwent transthoracic ASD repair along with mitral and tricuspid valvuloplasty. This report emphasizes the importance of educating patients about congenital malformations and potential interventions in developing countries, particularly in rural communities.  相似文献   
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Recent studies have suggested that sleep is associated with IQ measures in children, but the underlying mechanism remains unknown. An association between sleep spindles and IQ has been found in adults, but only two previous studies have explored this topic in children. The goal of this study was to examine whether sleep spindle frequency, amplitude, duration and/or density were associated with performance on the perceptual reasoning, verbal comprehension, working memory, and processing speed subscales of the Wechsler Intelligence Scale for Children-IV (WISC-IV). We recruited 29 typically developing children 7–11 years of age. We used portable polysomnography to document sleep architecture in the natural home environment and evaluated IQ. We found that lower sleep spindle frequency was associated with better performance on the perceptual reasoning and working memory WISC-IV scales, but that sleep spindle amplitude, duration and density were not associated with performance on the IQ test.  相似文献   
150.

Five years after the publication of DSM-5 in 2013, three widely used diagnostic instruments have published algorithms designed to represent its (sub-)criteria for Autism Spectrum Disorder (ASD) in children and adolescents. This study aimed to: (1) establish the content validity of these three DSM-5-adapted algorithms, and (2) identify problems with the operationalization of DSM-5 diagnostic criteria in measurable and observable behaviors. Algorithm items of the Autism Diagnostic Observation Schedule—Second Edition (ADOS-2), Developmental, Dimensional and Diagnostic Interview (3di) and Diagnostic Interview for Social and Communication Disorders—11th edition (DISCO-11) were mapped onto DSM-5 sub-criteria. The development and decision-making rules integrated in their algorithms were then compared with DSM-5. Results demonstrated significant variability in the number and nature of sub-criteria covered by the ADOS-2, 3di and DISCO-11. In addition to differences in the development of algorithms and cut-off scores, instruments also differed in the extent to which they follow DSM-5 decision-making rules for diagnostic classification. We conclude that such differences in interpretation of DSM-5 criteria provide a challenge for symptom operationalization which will be most effectively overcome by consensus, testing and reformulation.

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