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The increasing popularity of open management of the septic abdomen has generated a challenge that the surgeon is forced to face more frequently. The typical presentation is that of a patient with a full-thickness abdominal wall defect occurring after a protracted, severe illness. The various methods of reconstruction of the abdominal wall are reviewed and evaluated. The reconstruction should only be attempted once intra-abdominal sepsis is controlled, re-exploration of the peritoneal cavity is no longer necessary and organ support is discontinued. Although various methods of reconstruction are described, the recommended technique consists of either medial advancement of the rectus abdominis muscle or direct application of split-thickness skin grafts. Mid-line abdominal defects may also be repaired with tensor fasciae latae or rectus femoris flaps.  相似文献   
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Rules for the classification of Nonverbal Learning Disabilities (NLD) and Basic Phonological Processing Disabilities (BPPD) that had been generated and tested on older children (ages 9-15) were applied to younger children (ages 7-8). The goal was to evaluate the applicability of these classification rules for a younger population with NLD and BPPD, and to make revisions if necessary. These rules were used to differentiate these two subtypes of learning disabilities using levels and patterns of performance on motor/psychomotor, tactile/perceptual, visual-spatial, auditory-perceptual, problem solving, and language measures. An experienced child-clinical neuropsychologist classified each child. Only those children who received a classification of NLD or BPPD by the neuropsychologist and those who met criteria for definite or probable NLD and BPPD as defined by the rules were used in this study. Revisions were made to these rules for younger children. Revised rules allow for their use as a source of information to assist a clinician in deciding whether a comprehensive neuropsychological evaluation would be valuable. They may also be useful for research purposes.  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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Objective: To investigate the neuroprotective effects of Syzygium aromaticum(S.aromaticum)extract(500 mg/kg) on AlCl_3(300 mg/kg)-induced mouse model of oxidative stress and neurotoxicity.Methods: An ethanolic extract of S.aromaticum seeds was prepared and the active compounds were identified using nuclear magnetic resonance spectroscopy.BALB/c mice were divided into five groups(negative control, AlCl_3-treated, self-recovery, AlCl_3 + S.aromaticum, S.aromaticum only; n=10) and treated with AlCl_3 and S.aromaticum extract.Expression of oxidative markers [Superoxide dismutase 1(SOD1) and peroxiredoxin 6(Prdx6)] and amyloid precursor protein(APP) in the hippocampus and cortex was evaluated via PCR.Histopathological assessment was performed to investigate the extent of neurodegeneration.Results: It was observed that AlCl_3 exposure increased the expression of APP770 while simultaneously down regulated the expression of APP695.AlCl_3 also induced a significant decrease(P0.05) and an increase(P0.05) in the expression level of SOD1 and Prdx6, respectively.A substantial decrease substantial(P0.05) in the density of Nissl substance was also observed in cortex of the mice treated with AlCl_3.Interestingly, treatment with S.aromaticum extract normalized the alterations in the expression level of SOD1, Prdx6 and APPisoforms and improved the neuronal structural damage.Conclusions: The results showed that S.aromaticum is a promising antioxidant and a neuroprotective agent.  相似文献   
6.
In UK medical schools, five-option single-best answer (SBA) questions are the most widely accepted format of summative knowledge assessment. However, writing SBA questions with four effective incorrect options is difficult and time consuming, and consequently, many SBAs contain a high frequency of implausible distractors. Previous research has suggested that fewer than five-options could hence be used for assessment, without deterioration in quality. Despite an existing body of empirical research in this area however, evidence from undergraduate medical education is sparse. The study investigated the frequency of non-functioning distractors in a sample of 480 summative SBA questions at Cardiff University. Distractor functionality was analysed, and then various question models were tested to investigate the impact of reducing the number of distractors per question on examination difficulty, reliability, discrimination and pass rates. A survey questionnaire was additionally administered to 108 students (33 % response rate) to gain insight into their perceptions of these models. The simulation of various exam models revealed that, for four and three-option SBA models, pass rates, reliability, and mean item discrimination remained relatively constant. The average percentage mark however consistently increased by 1–3 % with the four and three-option models, respectively. The questionnaire survey revealed that the student body had mixed views towards the proposed format change. This study is one of the first to comprehensively investigate distractor performance in SBA examinations in undergraduate medical education. It provides evidence to suggest that using three-option SBA questions would maximise efficiency whilst maintaining, or possibly improving, psychometric quality, through allowing a greater number of questions per exam paper.  相似文献   
7.
Purpose

Pulmonary function testing (PFT) in patients with tracheostomies has been perceived as difficult to perform and clinically unreliable. We studied the feasibility, quality, repeatability and clinical significance of PFT.

Methods

Patients with tracheostomies that underwent PFT from January 1, 2010 to February 29, 2012 were identified. Clinical history and PFT data were reviewed retrospectively.

Results

Fifty patients (88% men) were identified. Forty-seven (94%) patients were able to perform PFT. Acceptable repeatability was obtained for FVC in 39 (83%) and for FEV1 in 41 (87%). Patients with tracheostomies showed difficulty in meeting ATS end-of-test criteria; only 9 (19%) met plateau criteria and 25 (53%) had exhalation times of greater than 6 s. Obstructive pattern was observed in 30 (64%) and restrictive pattern in 9 (19%). DLCO measurements were attempted in 43 patients and satisfactorily obtained in 34 (79%).

Conclusions

PFT can be performed with reliability in patients with tracheostomies, and they are useful for detecting and classifying types of lung dysfunction.

  相似文献   
8.
To characterize the genomic context of New Delhi metallo-β-lactamase-1 (NDM-1) and Klebsiella pneumoniae carbapenemase (KPC), we sequenced 78 Enterobacteriaceae isolates from Pakistan and the United States encoding KPC, NDM-1, or no carbapenemase. High similarities of the results indicate rapid spread of carbapenem resistance between strains, including globally disseminated pathogens.  相似文献   
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