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1.
PURPOSE: To compare, using a prospective, randomized controlled study, three methods of teaching a medical school parasitology course: computer-based instruction, traditional lecture-based instruction, and a combination of computer-based and lecture-based instruction. METHOD: A single class of the University of Utah School of Medicine was randomized into three study groups for the second-year parasitology course. The computer group (n = 29) used a locally developed interactive parasitology computer program; the lecture group (n = 32) had traditional lectures, and the combined group (n = 33) used both the computer program and lectures. Students' knowledge was assessed using a pretest, a final examination, and a posttest administered four months after the course. Students also used logs to track the amounts of time they spent studying. Their impressions and course evaluations were collected using a standardized course-evaluation form. RESULTS: The groups' scores on the pretest, final examination, and posttest were not statistically significantly different. Students in the computer group averaged 26.8 hours of studying over the two-week course compared with 32.1 hours in the lecture group and 32.7 hours in the combined group. The difference in study times between the computer and combined groups yielded a significant p value of 0.036. Students were generally positive about the course and the computer program. CONCLUSION: Students can learn parasitology from computer-based instruction as effectively as from traditional lecture-based instruction, and they can do so in less time.  相似文献   
2.
Physiologic assessment of diseases of the motor unit from the anterior horn cells to the muscles relies on a combination of needle electromyography (EMG) and nerve conduction studies (NCS). Both require a unique combination of knowledge of peripheral nervous system anatomy, physiology, pathophysiology, diseases, techniques, and electricity is necessary. Successful, high‐quality, reproducible EMG depends on the skills of a clinician in patient interaction during the physical insertion and movement of the needle while recording the electrical signals. These must be combined with the skill of analyzing electric signals recorded from muscle by auditory pattern recognition and semiquantitation. 10 , 52 This monograph reviews the techniques of needle EMG and waveform analysis and describes the types of EMG waveforms recorded during needle EMG. © 2009 Wiley Periodicals, Inc. Muscle Nerve 39: 244–270, 2009  相似文献   
3.
作者报道2例确诊的慢性丙肝病毒感染患者合并获得性大疱性表皮松解症(EBA)。两例患者临床上均表现为典型EBA,包括皮肤脆性增加及自发和继发于外伤后发生皮肤水疱,继而以粟丘疹和瘢痕愈合。EBA常常是一种免疫状态改变或低下的疾病。还需进一步研究在这两例患者中和一般情况下丙肝病毒是否诱发EBA。  相似文献   
4.
Bronchopulmonary dysplasia (BPD) is a pulmonary disorder that causes significant morbidity and mortality in premature infants. BPD is pathologically characterized by inflammation, fibrosis, and mucosal necrosis, which leads to emphysematous coalescence of alveoli. We tested the hypothesis that azithromycin, a macrolide antibiotic, would decrease the severity of lung injury in an animal model of BPD. Sixty-three rat pups were randomly divided equally into control, hyperoxia, and hyperoxia plus azithromycin groups. The hyperoxia groups were exposed to > 95% oxygen from days of life 4 to 14. On day 14, the animals were processed for lung histology and tissue analysis. Lung morphology was assessed by mean linear intercept, a measure of alveolar size, with larger values corresponding to lungs that are more emphysematous. The degree of lung inflammation was assessed by quantifying interleukin-6 (IL-6) from lung homogenate. Fifty pups survived to day 14 (control = 21, hyperoxia = 11, hyperoxia + azithromycin = 18). Mortality was increased in the hyperoxia group versus the control group (p < .0001). Treatment with azithromycin improved survival in animals subjected to hyperoxia (p < .05). Azithromycin significantly decreased lung damage as determined by the mean linear intercept in the hyperoxia groups (p < .001). Finally, azithromycin-treated pups had lower levels of IL-6 in lung homogenate from the hyperoxia groups (p < .05). Azithromycin treatment resulted in improved survival, less emphysematous change, and decreased IL-6 levels in an animal model of BPD.  相似文献   
5.
The Src-homology 2 domain-containing, leukocyte-specific phosphoprotein of 76 kDa (SLP-76) is a hematopoietic adaptor that plays a central role during immunoreceptor-mediated activation of T lymphocytes and mast cells and collagen receptor-induced activation of platelets. Despite similar levels of expression in macrophages, SLP-76 is not required for Fc receptor for immunoglobulin G (IgG; FcgammaR)-mediated activation. We hypothesized that the related adaptor SLP-65, which is also expressed in macrophages, may compensate for the loss of SLP-76 during FcgammaR-mediated signaling and functional events. To address this hypothesis, we examined bone marrow-derived macrophages (BMM) from wild-type (WT) mice or mice lacking both of these adaptors. Contrary to our expectations, SLP-76(-/-) SLP-65(-/-) BMM demonstrated normal FcgammaR-mediated activation, including internalization of Ig-coated sheep red blood cells and production of reactive oxygen intermediates. FcgammaR-induced biochemical events were normal in SLP-76(-/-) SLP-65(-/-) BMM, including phosphorylation of phospholipase C and the extracellular signaling-regulated kinases 1 and 2. To determine whether macrophages functioned normally in vivo, we infected WT and SLP-76(-/-) SLP-65(-/-) mice with sublethal doses of Listeria monocytogenes (LM), a bacterium against which the initial host defense is provided by activated macrophages. WT and SLP-76(-/-) SLP-65(-/-) mice survived acute, low-dose infection and showed no difference in the number of liver or spleen LM colony-forming units, a measure of the total body burden of this organism. Taken together, these data suggest that neither SLP-76 nor SLP-65 is required during FcgammaR-dependent signaling and functional events in macrophages.  相似文献   
6.
Abuse of the combination of pentazocine (P) and tripelennamine (T) reputedly produces an opiate-like euphoria not obtainable from either drug alone. To determine if this effect is related to interactions at the behavioral or receptor levels we tested this combination in rats trained to discriminate morphine from saline and in mu-receptor binding assays. Displacement of 3H-DHM was compared in morphine-naive, dependent and withdrawn states to determine the importance of prior morphine exposure. The morphine training cue (3 mg/kg) generalized to P but not to T. Combinations of T (0.3 and 1.0 mg/kg) with "no effect" doses of P (1 and 3 mg/kg) resulted in greater than additive increases in morphine-like responding. 3H-DHM was displaced by P but not T in naive, dependent and withdrawn states. Specific dose combinations of T (1 nM) with P (1 nM, 10 nM, 100 nM) resulted in enhanced displacement of 3H-DHM and was not related to prior morphine exposure. We conclude that the addition of T to P increases the mu-like subjective effects of P and this effect may be due to enhanced affinity of P for the mu-receptor.  相似文献   
7.
8.
We examined the association of body mass index (BMI) with sociodemographic data, medical comorbidities and hospital admission following ambulatory foot and ankle surgery. We conducted an analysis utilizing data from the American College of Surgeons National Surgical Quality Improvement Program database from 2007 to 2016. Adult patients who underwent ankle surgery defined as ankle arthrodesis, ankle open reduction and internal fixation, and Achilles tendon repair in the outpatient setting. We examined 6 BMI ranges: <20 kg/m2 underweight, ≥20 to <25 kg/m2 normal weight, ≥25 to <30 kg/m2 overweight, ≥30 to <40 kg/m2 obese, ≥40 kg/m2to <50 kg/m2 severely obese, and ≥50 kg/m2 extremely obese. The primary outcome was hospital admission. We performed multivariable logistic regression and reported odds ratios (OR) and their associated 95% confidence interval (CI) and considered a p value of <.05 as statistically significant. Data extraction yielded 13,454 adult patients who underwent ambulatory ankle surgery. We then performed listwise deletion to exclude cases with missing observations. After excluding 5.4% of the data, the final study population included 12,729 patients. The overall rate of hospital admission was in the population was 18.6% (2,377/12,729). The overall rate of postoperative complications was 0.03% (4/12,729). We found no significant association of BMI with hospital admission following multivariable logistic regression. We recommend that BMI alone should not be solely used to exclude patients from having ankle surgery performed in an outpatient setting, especially since this patient group makes up a significant proportion of orthopedic surgery.  相似文献   
9.
Archives of Sexual Behavior - Sexual minority men (SMM) remain disproportionately burdened by sexually transmitted infections. Although gay community involvement has been theorized to be protective...  相似文献   
10.
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