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1.
A 5-year-old boy presented with history of failure to thrive from infancy. There was a history of one sibling death due to similar problems and history of severe abortions in the mother. Routine examination of peripheral smear revealed more than 50% acanthocytes. Based on this tests were streamlined to doing lipid profile and Lipo protein electrophoresis which revealed hypolipidemia and absent Β hypo protein band. Jejuna) mucosal biopsy confirmed the diagnosis of A Beta Lipo proteinemia which revealed lipid laden enterocytes. This case illustrates the importance of simple tests like peripheral smear examination in streamlining further tests in the diagnosis of major diseases.  相似文献   
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Actinobacillus actinomycetemcomitans, an oral bacterium implicated in human periodontal disease, was recently demonstrated to invade cultured epithelial cells (D. H. Meyer, P. K. Sreenivasan, and P. M. Fives-Taylor, Infect. Immun. 59:2719-2726, 1991). This report characterizes the requirements for invasion of KB cells by A. actinomycetemcomitans. The roles of bacterial and host factors were investigated by using selective agents that influence specific bacterial or host cell functions. Inhibition of bacterial protein synthesis decreased invasion, suggesting the absence of a preformed pool of proteins involved in A. actinomycetemcomitans invasion. Inhibition of bacterial and eukaryotic energy synthesis also decreased invasion, confirming that A. actinomycetemcomitans invasion is an active process. Bacterial adherence to KB cells was indicated by scanning electron microscopy of infected KB cells. Further, the addition of A. actinomycetemcomitans-specific serum to the bacterial inoculum reduced invasion substantially, suggesting a role for bacterial attachment in invasion. Many of the adherent bacteria invaded the epithelial cells under optimal conditions. Inhibitors of receptor-mediated endocytosis inhibited invasion by A. actinomycetemcomitans. Like that of many facultatively intracellular bacteria, A. actinomycetemcomitans invasion was not affected by eukaryotic endosomal acidification. These are the first published observations describing the requirements for epithelial cell invasion by a periodontopathogen. They demonstrate that A. actinomycetemcomitans utilizes a mechanism similar to those used by many but not all invasive bacteria to gain entry into eukaryotic cells.  相似文献   
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Thirty children in the age group of 2 to 12 years were brought with a history of recurrent non-seasonal moderate to severe wheezy episodes associated with symptoms of nasal congestion, sneezing and occasional headache. All of them had maxillary or pan sinusitis with 26 having associated right, left or bilateral lower lobe pneumonitis or bronchiectasis. Serum immunoglobulins were normal in 22 and was not done in eight. There was positive (2 to 4+ above negative control) skin test response to dust and dust mite in 15 of the 22 children tested. Throat swabs/sputum or nasal secretions grew B-hemolytic streptococcus or streptococcus pneumoniae in twenty-seven. All the children were put on bactericidal drugs for 6 to 8 weeks and bronchodilators were used when needed. At the end of 6 to 8 weeks follow-up X-ray of sinuses and chest showed significant clearing of the lesions which coincided with marked clinical improvement. Sinus X-ray should be considered in bronchial asthma resistant to medical management since untreated bacterial sinusitis can be an underlying cause of chronic poorly controlled asthma.  相似文献   
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Juveniles tried as adults (JTA) represent a select and small subsample of juvenile offenders. This study seeks to provide a profile of habitually violent JTAs transferred to the adult penal system and to compare them with their adult counterparts. Twenty-nine incarcerated violent male juveniles tried as adults were compared with a sample of 27 incarcerated violent male offenders across demographic, neuropsychological, criminal history, psychopathy, and substance abuse variables. The JTAs were characterized by a high rate of gang membership (96%), substance abuse (alcohol, marijuana, and phenylcyclidene), and use of guns. In the juvenile sample, 65 percent used guns in violence not leading to arrest, and 93 percent used guns in a violent crime leading to arrest. Juvenile offenders were similar to their adult counterparts in patterns of criminality, although adult offenders had higher psychopathy scores. Both groups revealed generally intact neuropsychological functioning with the exception of a higher rate of perseverative responses in the adult sample. The results are discussed in terms of the implication of the degree of violence in a young offender population.  相似文献   
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Avascular necrosis (AVN) is idiopathic in about 40% of cases. The pathophysiology of avascular necrosis remains incompletely elucidated. Here, we report a case that underlines the role for inherited factors in AVN of the femoral heads. Idiopathic AVN of the femoral heads occurred in five members of the same family (a woman, her two paternal aunts, her male paternal cousin and her female paternal cousin) at a mean age of 42.4 years (range, 33–58 years). Standard pelvic radiographs showed Arlet and Ficat stage 4 AVN in three patients and stage 3 in two patients. None of the patients had a history of glucocorticoid therapy, alcohol abuse, or trauma. All five patients underwent investigations for a cause, including blood cell counts, a lipid profile, coagulation tests, testing for antinuclear antibodies, hemoglobin electrophoresis, ultrasonography of the abdomen, and standard radiographs of the long limb bones. The results were normal or negative, ruling out known hereditary causes of AVN such as sickle cell anemia and Gaucher disease. Many cases of familial AVN of the femoral head have been described in patients with sickle cell anemia or Gaucher disease. However, only five families with idiopathic familial AVN of the femoral heads have been reported (three in the US and two in Taiwan). All the patients in these families had isolated bilateral AVN of the femoral heads without AVN at other sites.  相似文献   
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Clinical Oral Investigations - This study compared the effects of oral hygiene with a toothpaste formulated with zinc (test) to a fluoride dentifrice (control) for effects on oral polymorphonuclear...  相似文献   
10.
Problem: Studies on leadership identity development through reflection with Team-Based Learning (TBL) in medical student education are rare. We assumed that reflection and feedback on the team leadership process would advance the progression through leadership identity development stages in medical students within the context of classes using TBL. Intervention: This study is a quasi-experimental design with pretest–posttest control group. The pretest and posttest were reflection papers of medical students about their experience of leadership during their TBL sessions. In the intervention group, TBL and a team-based, guided reflection and feedback on the team leadership process were performed at the end of all TBL sessions. In the other group, only TBL was used. The Stata 12 software was used. Leadership Identity was treated both as a categorical and quantitative variable to control for differences in baseline and gender variables. Chi-square, t tests, and linear regression analysis were performed. Context: The population was a cohort of 2015–2016 medical students in a TBL setting at Tehran University of Medical Sciences, School of Medicine. Teams of four to seven students were formed by random sorting at the beginning of the academic year (intervention group n = 20 teams, control group n = 19 teams). Outcome: At baseline, most students in both groups were categorized in the Awareness and Exploration stage of leadership identity: 51 (52%) in the intervention group and 59 (55%) in the control group: uncorrected χ2(3) = 15.6, design-based F(2.83, 108) = 4.87, p = .003. In the posttest intervention group, 36 (36%) were in exploration, 33 (33%) were in L-identified, 20 (20%) were in Leadership Differentiated, and 10 (10%) were in the Generativity. None were in the Awareness or Integration stages. In the control group, 3 (20%) were in Awareness, 56 (53%) were in Exploration, 35 (33%) were in Leader Identified, 13 (12%) were in Leadership Differentiated. None were in the Generativity and Integration stages. Our hypothesis was supported by the data: uncorrected χ2(4) = 18.6, design-based F(3.77, 143) = 4.46, p = .002. The mean of the leadership identity in the pretest, intervention group equaled 1.93 (SD = 0.85) and the pretest, control group mean was 2.36 (SD = 0.86), p = .004. The mean of the posttest, intervention group was 3.04 (SD = 0.98) and posttest, control group mean was 2.54 (SD = 0.74), T = ?4.00, design df = 38, p < .001, and adjusted on baseline and gender T = ?8.97, design df = 38, p < .001. Lessons Learned: Reflection and feedback on the team leadership process in TBL advances the progression in stages of leadership identity development in medical students. Although the TBL strategy itself could have an impact on leadership identity development, this study demonstrates that when a reflection and feedback on leadership intervention are added, there is much greater impact.  相似文献   
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