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Myocardial fibrosis can occur as a complication of chronic infection of the heart with Trypanosoma cruzi (Chagas' disease) and can lead to serious disability. To assess whether there might be a direct relationship between intracellular parasitization and subsequent tissue fibrosis in this disease, we tested serum-free conditioned media from cultures of fibroblasts, vascular smooth-muscle cells, and myocardial cells for fibroblast-stimulating activity. Conditioned media from all infected cultures, but not from uninfected cultures, stimulated fibroblast [3H]thymidine incorporation, DNA and protein synthesis, and cell proliferation. Fibroblast-stimulating activity was also detected in extracts of amastigotes but not of trypomastigotes or epimastigotes. We conclude that parasitization of mesenchymal cells, including myocardial cells, results in elaboration of a fibroblast-stimulating factor(s), perhaps of parasite origin. We postulate that this factor may play a role in initiation of myocardial fibrosis in Chagas' disease.  相似文献   
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OBJECTIVE: This study was designed to investigate potential areas of practice for the clinical laboratory scientist (CLS) and to propose a graduate curriculum to prepare the practitioner for an advanced level of practice. DESIGN: Meta-analysis of PharmD, physician assistant, physical therapy, and nurse practitioner curricula focusing on academic and clinical advanced practice was used to develop an educational model and curriculum for a professional doctorate in clinical laboratory science (CLS). MAIN OUTCOME MEASURE: (1) New educational model for CLS advanced practice; (2) A proposed curriculum for a Doctorate of Clinical Laboratory Science degree. RESULTS: A new curriculum model was adapted from established healthcare educational models. CONCLUSION: Although there is a need for a baccalaureate degree in CLS there is also a role for expanded education and responsibilities for CLS practitioners. The CLS Advanced Practitioner design focuses on moving students from the baccalaureate level to the doctoral level and prepares the individual to become an integral part of the healthcare team.  相似文献   
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Over recent decades, the use of in vitro diffusion cell studies to assess skin permeability has evolved into a major research tool, providing key insights into the relationships between skin, drug and formulation. Sometimes, such studies involve synthetic membranes as this approach can yield useful inferences with respect to drug-skin partitioning and diffusion phenomena. Yet despite the popularity of such studies, it is still not at all known whether typical solute transport across synthetic barriers results in a normal distribution of permeability coefficients or alternatively some type of skewed distribution. The present study aims to shed light on this issue. To this end, five compounds (testosterone, oestradiol, corticosterone, aldosterone and adenosine) exhibiting a broad range of octanol-water partition coefficient values were selected as test penetrants. The protocol involved taking multiple replicate measurements of each drug's passive steady state flux through poly(dimethylsiloxane) membrane. Each penetrant's resultant permeability coefficient database was subjected to a Kolmogorov-Smirnov (KS) test for normality. It was found that the permeability coefficients of all five drugs were distributed in a Gaussian-normal fashion. The theoretical significance and practical impact of these findings are discussed.  相似文献   
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Background: Remifentanil is commonly used to replace nitrous oxide in general anesthesia to avoid the side effects of the latter. However, there are reports that intraoperative remifentanil infusion can lead to acute opioid tolerance. In this study, the authors tried to determine the dose of remifentanil comparable in efficacy to 70% nitrous oxide and to evaluate its effect on postoperative pain and morphine consumption after colorectal surgery using isoflurane anesthesia.

Methods: Sixty adult patients undergoing open colorectal surgery were randomly assigned to receive either remifentanil or 70% nitrous oxide along with isoflurane anesthesia. After morphine analgesia titration in the postanesthesia care unit, patient-controlled analgesia was commenced. Morphine consumption and pain were scored at rest and during cough or movement for 24 h.

Results: The mean remifentanil infusion rate was 0.17 [mu]g [middle dot] kg-1 [middle dot] min-1. The median visual analog pain score on arrival in the postanesthesia care unit was 1 (0-10) in the nitrous oxide group and 3 (0-9) in the remifentanil group (P < 0.05). Otherwise, there was no difference in pain scores at 5, 10, and 15 min and no difference in the total morphine consumption during the stay in the postanesthesia care unit. The two groups had similar total morphine consumption in the first 24 h and pain scores at rest and during movement. The incidence of postoperative nausea and vomiting was 10% in both groups. There was no difference in the sedation scores.  相似文献   

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Attention-deficit/hyperactivity disorder (ADHD) is associated with impairments in occupational, social, and educational functioning in adults. This study examined relations of adaptive impairment to ADHD symptom domains (inattentive-disorganized and hyperactive-impulsive) and to deficits in executive functioning (EF) in 195 well-characterized adults (105 ADHD, 90 non-ADHD, between ages 18 and 37). Participants completed a battery of EF measures as well as assessments of adaptive functioning. Confirmatory factor analyses were used to validate latent factors for adaptive functioning and EF. In a measurement model, weaker EF was associated with poorer adaptive functioning (r = -.30). When multi-informant composite variables for current inattentive-disorganized and hyperactive-impulsive ADHD symptoms were included in the structural model, EF no longer predicted adaptive functioning. While both symptom composites were similarly related to EF (inattentive-disorganized r = .36; hyperactive-impulsive r = .29), inattentive-disorganized symptoms accounted for more variance in adaptive functioning (67.2% vs. 3.6%). Furthermore, for retrospectively reported childhood symptoms of ADHD, only the inattentive-disorganized symptom domain was related to EF or adaptive impairment. These results suggest that, in adults with ADHD, inattentive-disorganized symptoms may be the primary contributor to key aspects of poorer adaptive function and may be the behavioral path through which EF deficits lead to adaptive impairment.  相似文献   
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The purpose of this study was to appraise the value of PET in the assessment of the effect of supposedly proangiogenic new therapies such as gene therapy with vascular endothelial growth factor (VEGF) gene and endomyocardial laser therapy. METHODS: Thirty-five patients with end-stage coronary artery disease and class III (Canadian Cardiovascular Society) angina were included. Myocardial ischemia was evaluated with dipyridamole PET scanning and exercise tolerance with bicycle ergometry. Ten patients were treated with naked plasmid DNA encoding for human VEGF165 (VEGF) and 12 patients were treated with laser therapy (direct myocardial revascularization [DMR]) using an electromechanical mapping system. Thirteen patients were treated with standard medical therapy (control). RESULTS: In both active treatment groups, angina was reduced in most subjects, except in 2 VEGF and 5 DMR patients. In the control group, no improvement in anginal classification was found, except in 3 subjects. On the PET scan, solely in the VEGF group, the stress perfusion was significantly improved (from 57 +/- 33 to 81 +/- 55 mL/min/100 g; P = 0.031). Furthermore, in the VEGF group, the number of ischemic segments was reduced from 274 +/- 41 to 234 +/- 48 segments (P = 0.004) but not in the DMR group (from 209 +/- 43 to 215 +/- 52 segments) or in the control group (from 218 +/- 18 to 213 +/- 28 segments). Bicycle exercise duration showed slight nonsignificant changes in the VEGF group (from 3.6 +/- 2.0 to 4.6 +/- 2.1 min), in the DMR group (from 5.1 +/- 1.5 to 4.7 +/- 1.3 min), and in the control group (from 3.3 +/- 1.8 to 3.5 +/- 2.3 min). CONCLUSION: PET showed that intramyocardial gene therapy with the human VEGF165 gene in contrast to laser DMR treatment effectively reduces myocardial ischemia.  相似文献   
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