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31.
G. Chan  C. K. Chan 《Hernia》2005,9(1):37-41
At the Shouldice Clinic pre-operative weight loss is used prior to incisional hernia repairs. Mesh repair is selectively used, based on specific hernia characteristics. A series of 236 patients were reviewed and followed up for 36 months. Data were available on 188 patients (80%). There were 15 recurrences (8%). The number of obese patients was reduced from 67 (35.6%) to 25 (13.3%) through the weight loss program. The hernia diameter, gastrointestinal complications, and surgical site infection were significantly related to recurrence but not the type of repair, obesity, location, or previous recurrences. The risk factors of incisional hernias include size, intestinal complications and infections. A selective use has a comparable result to the exclusive use of mesh repair. Weight reduction has yet to be shown to affect the rate of recurrence, and further prospective studies are required.  相似文献   
32.
Background and Objectives: The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations.
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders.  相似文献   
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Quinone(di)imines are nitrogen analogues of quinones in which one or both quinone oxygens are replaced by an imino group. A series of quinone(di)imines with antitumor activity has been studied for its in vitro chemical reactivity, metabolism, acute toxicity to primary cultured rat hepatocytes, and growth-inhibitory activity with Chinese hamster ovary (CHO) cells. The quinone(di)imines exhibited a wide range of activity as substrates for metabolism by hepatic microsomal flavoenzymes. The maximum rate of quinone(di)imine metabolism was more than 7.5-fold greater than reported for metabolism of quinones. Some quinone(di)imines formed free radicals that could be detected by electron spin resonance spectroscopy. 2-Amino-1,4-naphthoquinoneimine gave a short-lived electron spin resonance signal that could be detected only under aerobic conditions. 2,3',6-Trichloroindophenol gave an electron spin resonance signal in air that was stable for 24 h. Most quinone(di)imines underwent oxidation-reduction cycling to form the superoxide anion radical, but some quinone(di)imines, although rapidly metabolized, formed little or no superoxide anion radical. Quinone(di)imines were relatively toxic to hepatocytes and CHO cells, and some quinone(di)imines were more toxic to one cell type than the other. The log 1-octanol/water partition coefficient showed an optimal value of 2.61 for toxicity against both cell types. In hepatocytes the more toxic quinone(di)imines were the most rapidly metabolized. For a subgroup of quinone(di)imines toxicity to hepatocytes and CHO cells appeared to be related to the ability to form a semiquinone(di)imine free radical. Toxicity of quinone(di)imines to hepatocytes and CHO cells was not related to superoxide anion radical formation, and toxicity to CHO cells was not affected by exclusion of oxygen during exposure of the cells to the compounds. The rate of chemical addition of quinone(di)imines to reduced glutathione did not correlate with toxicity. An understanding of the mechanisms of acute toxicity and growth-inhibitory activity of quinone(di)imines could lead to the design of more selective quinonoid antitumor agents.  相似文献   
35.
We identified 18 patients with double-orifice mitral valve (DOMV) and intact atrioventricular (AV) septum out of 40,179 echocardiographic studies performed between 1997 and 2002 at Children's Hospital, Denver, CO. In this study we describe (1) the anatomic characteristics of the DOMV in the absence of AV septal defect, (2) the function of the mitral valve by spectral and color Doppler flow mapping, and (3) associated lesions. The topographic location of the orifices in the leaflets suggests possible embryologic mechanisms of DOMV. In this series, DOMV was most commonly associated with left-sided obstructive lesions (in 39% of patients). Spectral and color Doppler interrogation demonstrated a normal flow profile in most cases; only 2 patients had significant mitral regurgitation or stenosis. Therefore, due to the uncertain natural history of this lesion and the potential need for endocarditis prophylaxis, careful imaging of the mitral valve is recommended, particularly in the presence of left-sided obstructive lesions.  相似文献   
36.
This study examines how acute hand injuries affect patients in their roles as spouse, caregiver, and/or worker. Qualitative data from patient interviews were used to analyze how these life roles were affected by the individuals' hand injuries. Data were extracted from interviews of three hand patients who had one or more roles of spouse, caregiver, and/or worker affected by their injury. Data were then examined and categorized for each life role by participant. Participants' views of how hand therapy affected their recovery and resumption of occupational role performance were also examined. Results showed that the participants expressed profound degrees of change in their ability to perform satisfactorily in their various life roles.  相似文献   
37.
BACKGROUND: Increased autoantibody prevalence has been described in instances of high-dose exposure to polychlorinated biphenyls (PCBs). In 1996, an equipment malfunction at the Swan Hills Treatment Centre in Alberta, Canada, caused the release of gases containing PCBs into the ambient air. In view of the immune effects of PCBs and their potential as endocrine disruptors, we assessed autoantibody prevalence and looked for correlations with PCB levels. METHODS: Fifty-seven persons living within a 100 km radius of the waste treatment facility were assessed. Autoantibodies were measured by indirect immunofluorescence, double immunodiffusion, and immunoblotting. The levels of 26 congeners of PCBs were measured by gas chromatography and mass spectrometry. Provincial health records for physician visits and hospitalizations were reviewed for diagnoses of autoimmune disease. RESULTS: The prevalence of autoantibodies was 11% in the study participants and 0% in healthy controls. There was no correlation of PCB levels with autoantibody results. There was no associated increase in autoimmune disease noted on physician visits or hospitalizations. PCB levels were comparable to background levels reported for other populations. CONCLUSION: A correlation of titers of autoantibodies in the sera of individuals at risk and the blood levels of PCBs was not found, and the prevalence of autoantibodies in the at-risk group was not statistically different (p > .05) from that of an unexposed control group. The study group had higher titers of autoantibodies and some strong reactivity with intracellular antigens, but the significance of this observation may be understood only after long-term clinical assessments and follow-up.  相似文献   
38.
Conventional work-up (CWU) with chest radiography, abdominal ultrasonography, and skeletal scintigraphy has limited value in M staging of nonkeratinizing nasopharyngeal carcinoma (NPC). Our aim was to evaluate whether (18)F-FDG PET could replace CWU by comparing their diagnostic efficacies. METHODS: Patients with histologically proven nonkeratinizing NPC and no prior treatment were prospectively enrolled. All study participants underwent CWU and (18)F-FDG PET for primary M staging. Distant metastasis was considered to be present if there was any reliable evidence identified within 1 y after diagnosis. The comparative diagnostic efficacies of (18)F-FDG PET, CWU, and the combination of (18)F-FDG PET and CWU (PET+CWU) were evaluated using the areas under the receiver-operating-characteristic (ROC) curves. RESULTS: Sixty-one (20.3%) of 300 eligible patients were found to have distant metastases. On a patient-based analysis, (18)F-FDG PET was found to be more effective than CWU (P < 0.001), whereas it was equally effective with PET+CWU (P = 0.130). On region-based analyses, (18)F-FDG PET was more effective than skeletal scintigraphy and chest radiography for detecting bone metastases (P < 0.001) and chest metastases (P < 0.001), respectively. (18)F-FDG PET and abdominal ultrasound were equally effective for detecting hepatic metastases (P = 0.127). On region-based analyses, the combination of (18)F-FDG PET and CWU did not yield any noticeable increase in diagnostic efficacy. CONCLUSION: (18)F-FDG PET can replace CWU in primary M staging of nonkeratinizing NPC.  相似文献   
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