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131.
132.
This population-based case-control study of North Carolina workplaces evaluated the hypothesis that employers' policies allowing firearms in the workplace may increase workers' risk of homicide. Workplaces where guns were permitted were about 5 times as likely to experience a homicide as those where all weapons were prohibited (adjusted odds ratio=4.81; 95% confidence interval=1.70, 13.65). The association remained after adjustment for other risk factors. The findings suggest that policies allowing guns in the workplace might increase workers' risk of homicide. 相似文献
133.
Demir Z Kurtay A Velidedeoğlu H Onur MA Atilla P Taş C Cakar N 《Aesthetic plastic surgery》2005,29(4):304-309
Recently, fat injection has gained favor among plastic surgeons for soft tissue augmentation. However, fat injections lose 50% of their volume after 1 year. The profession is in need of an injectable bulking material that gives a long-lasting improvement. Using 30 male rats, this study investigated the stability of the size and structure of the injected fascia autograft and compared it with surgically transplanted fascia. The fascia graft was harvested from the back of the rat, big, and divided into two equal pieces. The first piece was minced into a paste and injected subcutaneously on the anterior surface of the right ear. The other piece was transplanted subcutaneously on the anterior surface of the left ear. The grafts were observed for any sign of resorption over 1 to 6 months.Grossly, injection and transplantation sites were palpable at the end of the observation periods. Microscopic examination showed that injected fascia maintains its histomorphologic structure.These findings indicate that the injected fascia graft is well tolerated, and the size of the graft remained stable. According to this study, fascia injection can result in bulking material that gives a long-lasting improvement, and can be a viable alternative to other methods. 相似文献
134.
Ozatik MA Göl MK Fansa I Uncu H Küçüker SA Küçükaksu S Bayazit M Sener E Taşdemir O 《Journal of cardiac surgery》2005,20(1):52-57
BACKGROUND: Although the overall complication rates have been decreased significantly in recent years, stroke rates still remain high in patients undergoing coronary bypass operations. This study is designed to evaluate the risk factors for stroke in patients who had undergone coronary artery bypass surgery in an 8-year period in our clinic. METHODS: Between 1995 and 2003, 8547 coronary artery operations under cardiopulmonary bypass were performed. Retrospective analysis of the patient files revealed that 75 (0.9%) patients had stroke in the early postoperative period. RESULTS: Mean age of these patients was 62.3 +/- 9.5 years, and 54 (72%) were males. Stroke rate was 1.2% between 1995 and 1998 and this was significantly higher from the stroke rate (0.7%) of the period 1998 to 2003 (p = 0.03). Major technical differences between these two periods were the routine application of preoperative carotid arteries Doppler evaluation and intraoperative epiaortic echocardiography after 1998. Higher age (p = 0.000), female sex (p = 0.005), smoking (p = 0.03), presence of diabetes mellitus (p = 0.01), hypertension (p = 0.008), and left main coronary artery disease (p = 0.001), carotid surgery (p = 0.000), and peripheral vascular disease (p = 0.049) were identified as important risk factors in univariate analysis for stroke development. Higher age (p = 0.000; OR = 21.38), left main coronary artery disease (p = 0.007; OR = 7.26), peripheral vascular disease (p = 0.050; OR = 3.08), and operation date before 1998 (p = 0.012; OR = 6.33) were identified as important risk factors in logistic regression analysis. According to intraoperative epiaortic ultrasonography, operative strategy was changed in 9% of patients. Thirty-seven (49.3%) of the stroke patients died. Female sex (p = 0.023; OR = 5.18) and preoperative hypertension (p = 0.045; OR = 4.03) were observed as significant risk factors for mortality after stroke. CONCLUSION: Development of stroke is one of the major reasons of mortality after coronary artery bypass operations. It is essential to take all the measures to prevent this complication, especially in patients with known risk factors. Evaluation of carotid arteries prior to operation and application of routine intraoperative epiaortic echocardiography may in part eliminate stroke. 相似文献
135.
136.
Atouf F Choi Y Fowler MJ Poffenberger G Vobecky J Ta M Chapman GB Powers AC Lumelsky NL 《Cell transplantation》2005,14(10):735-748
Transplantation of pancreatic islets can provide long-lasting insulin independence for diabetic patients, but the current islet supply is limited. Here we describe a new in vitro system that utilizes adult human pancreatic islet-enriched fractions to generate hormone-producing cells over 3-4 weeks of culture. By labeling proliferating cells with a retrovirus-expressing green fluorescent protein, we show that in this system hormone-producing cells are generated de novo. These hormone-producing cells aggregate to form islet-like cell clusters. The cell clusters, when tested in vitro, release insulin in response to glucose and other secretagogues. After transplantation into immunodeficient, nondiabetic mice, the islet-like cell clusters survive and release human insulin. We propose that this system will be useful as an experimental tool for investigating mechanisms for generating new islet cells from the postnatal pancreas, and for designing strategies to generate physiologically competent pancreatic islet cells ex vivo. 相似文献
137.
OBJECTIVE: To investigate body fat composition, measured by bioelectrical impedance assay (BIA), for predicting the presence and severity of obstructive sleep apnea-hypopnea syndrome (OSAHS). Body fat composition was also compared with other well-known OSAHS predictors such as body mass index (BMI), neck circumference, and abdominal visceral fat. STUDY DESIGN: A prospective study was designed. Fifty-one patients (41 male, 10 female), who were referred to Hacettepe University Faculty of Medicine, Department of Otorhinolaryngology, Head and Neck Surgery with suspected OSAHS, between April 2003 and June 2004, were included in the study. METHODS: All patients underwent polysomnography (PSG) and were classified according to their apnea-hypopnea index (AHI) into four groups. The cross-sectional area of abdominal visceral fat was measured by computed tomography (CT) scanning in 33 of the patients. Neck circumference and BMI was measured for all patients. BIA was performed to determine body fat composition. The groups were compared, and correlation of the variables with AHI was investigated. RESULTS: Of the variables, BMI and percentage of body fat (determined by BIA) were found to be significantly correlated with AHI (r = 0.782, r = 0.647). CT of cross-sectional area of abdominal visceral fat provided 100% sensitivity and specificity (P < .001) in differentiating simple snorers from OSAHS patients. By combining percentage of body fat and body fat mass, higher levels of sensitivity (95%) and specificity (100%) were achieved for diagnosis of OSAHS. CONCLUSION: It was concluded that the BIA could be an inexpensive and practical alternative to prePSG screening tests and should be included in the evaluation of OSAHS patients. 相似文献
138.
139.
Bozkurt MC Tağil SM Ozçakar L Ersoy M Tekdemir I 《Clinical anatomy (New York, N.Y.)》2005,18(4):274-280
The aim of this study was to assess the anatomical variations, especially the anomalous muscles passing through Guyon's canal and the fibrous arch forming the piso-hamate hiatus, which may play a role in ulnar tunnel syndrome. We have also focused on the relation of these structures with specific concern to the ulnar nerve. Nineteen embalmed cadavers (37 hands and forearms) were dissected. A fibrous arch extending between the pisiform and the hook of the hamate was observed in 21 hands. In majority of the cases flexor digiti minimi muscle was found to originate only from this arch. An anomalous muscle was disclosed in six hands with four of them passing through the piso-hamate hiatus with the deep branch of the ulnar nerve. In two of four cases, the superficial branch of the ulnar nerve was also accompanying the deep branch of the ulnar nerve beneath the anomalous muscle and through the piso-hamate hiatus. Because these anomalous muscles were generally found to course through the piso-hamate hiatus with the branches of the ulnar nerve, we conclude that the distal portion of the Guyon's canal has a relatively higher risk for ulnar nerve entrapment. We believe that surgeons operating on this region should take into account these various anatomic structures. 相似文献
140.
Demirbilek S Karaman A Gürünlüoğlu K Akin M Taş E Aksoy RT Kekilli E 《Pediatric surgery international》2005,21(6):423-427
The association between gastroesophageal reflux (GER) and intestinal malrotation (IM) has been well described. Delayed or impaired gastric emptying in IM is thought to be a contributing factor in the development of gastroesophageal reflux disease (GERD). The current study assessed the role of malrotation in delayed gastric emptying in children with GERD. We also evaluated the interactions between GERD, malrotation, gastric pH abnormalities, and gastric dysmotility. Sixty-seven patients between 1 and 5 years of age (mean 3.08±1.2) and with symptoms of GER, such as emesis, reactive or recurrent lung disease, and/or growth retardation, were studied in 2001–2005. Upper and lower gastrointestinal contrast studies were performed for the diagnosis of malrotation. Gastric motility was evaluated with a liquid gastric emptying protocol. GER was documented by upper gastrointestinal studies, scintigraphy, and/or 24-h pH monitoring. In our series of 44 children with GERD, there was an unexpectedly high incidence of IM: 54.5% (24/44). IM has previously been known to occur in 25% of patients with GERD. GERD was found in 24 (82.7%) of 29 patients with IM. Mean nuclear gastric emptying (MNGE) was 51.6±8.04 min in patients with isolated GERD and 96.6±20.5 min in children with IM and GERD. There was a statistically significant difference in MNGE time (p<0.05) between children with primary GERD and in those with GERD and IM. Esophageal pH monitoring showed that mean fraction time below pH 4 was 7.06±1.1% in patients with isolated GERD and 14.7±4.1% in patients with IM and GERD. GERD is common in children between 1 and 5 years old. Using gastric emptying studies and esophageal pH monitoring, we have shown that gastric dysmotility and esophageal pH abnormalities are highly prevalent, especially in children with malrotation compared with children with isolated GERD. These findings suggest that malrotation is an important factor responsible for delayed gastric emptying in GERD. Hence, we recommend that all infants and children with GERD and delayed gastric emptying undergo careful evaluation for malrotation. 相似文献