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排序方式: 共有1303条查询结果,搜索用时 15 毫秒
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Erkan Yildirim Erkan Kaptanoglu Kanat Ozisik Ethem Beskonakli Ozerk Okutan Mustafa F Sargon Kamer Kilinc Unal Sakinci 《European journal of cardio-thoracic surgery》2004,25(4):523-529
OBJECTIVE: We aimed to demonstrate the time-dependent ultrastructural changes in pneumocyte type II cells following brain injury, and to propose an electron microscopic scoring model for the damage. METHODS: Forty Wistar-Albino female rats weighing 170-200 g were used. The rats were allocated into five groups. The first group was the control and the second was the craniotomy without trauma. The others were trauma groups. Weight-drop method was used for achieving head trauma. Samples were obtained from the right and left pulmonary lobes at 2-, 8-, and 24-h intervals after transcardiac perfusion. An electron microscopic scoring model was used to reveal the changes. RESULTS: There were no ultrastructural pathological findings pointing to lung injury in any rat of the control groups. There was intense intracellular oedema in type II pneumocyte and interstitial oedema in the adjacent tissue in trauma groups. Oedema in mitochondria and dilatation in both smooth endoplasmic reticulum and Golgi apparatus was more evident in the 8- and 24-h trauma groups. The chromatin dispersion was disintegrated in the nucleus in all trauma groups. Scores of all trauma groups were significantly different from the controls (P<0.05). All trauma groups were different from each other at significant levels (P<0.05 for each trauma groups). CONCLUSIONS: The data suggested that ultrastructural damage is obvious at 2 h and deteriorates with time. The electron microscopic scoring model worked well in depicting the traumatic changes, which were supported by lipid peroxidation. Further experiments are needed to determine the exact outcome after brain death model. 相似文献
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We report a case of Noonan syndrome associated with central giant cell granuloma. The patient was a 101/2-year-old boy with the chief complaint of proptosis of the right eye. He also had various malformations such as short stature, webbed neck, pectus excavatum, cubitus valgus, pulmonary valve stenosis and patent foramen ovale, a characteristic face appearance and cryptorchidism and so on. Chromosome analysis showed a 46, XY karyotype. A computed tomographic scan and magnetic resonance imaging showed a mass originated from the lateral wall of the right maxillary sinus. The patient underwent Caldwell-Luc operation. Histological examination of the mass showed the characteristics of central giant cell granuloma. This case report describes a patient with the features of the recently described Noonan-like/multiple giant cell lesion syndrome. 相似文献
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It has been suggested recently that acute intussusception should only be managed in a specialised paediatric centre. The aim of this study is to assess the incidence and outcome of acute intussusception in a comprehensive paediatric unit in Waterford Regional Hospital. It is a retrospective medical records study over a ten year period from June 1990 to June 2000. Our results showed that we had 24 cases giving an incidence of 2.4 cases per year. Contrast enema was performed in 23(95%) cases, successfully reduced in 14(61%) cases, unsuccessfully reduced in 7(30%). Surgical intervention was necessary in 7(30%) cases. Three (12.5%) cases were transferred to a specialised paediatric surgical centre. There were no perforation or death. We conclude from this study that management of acute intussusception can be successfully undertaken in a regional paediatric centre. It requires adequate throughput of cases and close co-operation between paediatrician, radiologist, anaesthetist, surgeons and of course a dedicated paediatric nursing staff. 相似文献
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BackgroundThere has been increasing uptake of minimally invasive pancreatoduodenectomy during the past decade, but it remains a highly specialized procedure as benefits over open pancreatoduodenectomy remain contentious. This study aimed to evaluate current evidence on minimally invasive pancreatoduodenectomy versus open pancreatoduodenectomy in terms of impact of center volume on outcomes.MethodsA systematic review of articles on comparative cohort and registry studies on minimally invasive pancreatoduodenectomy versus open pancreatoduodenectomy published until 31st December 2019 were identified, and meta-analyses were performed. Primary endpoints were International Study Group on Pancreatic Fistula grade B/C postoperative pancreatic fistula and 30-day mortality.ResultsAfter screening 7,390 studies, 43 comparative cohort studies (8,755 patients) with moderate methodological quality and 3 original registry studies (43,735 patients) were included. For the cohort studies, the median annual hospital minimally invasive pancreatoduodenectomy volume was 10. No significant differences were found in grade B/C postoperative pancreatic fistula (odds ratio: 0.98, 95% confidence interval: 0.78–1.23) or 30-day mortality (odds ratio: 1.14, 95% confidence interval: 0.65–2.01) between minimally invasive pancreatoduodenectomy when compared with open. No publication biases were present and meta-regression identified no confounding for grade B/C postoperative pancreatic fistula, center volume or 30-day mortality. Minimally invasive pancreatoduodenectomy was only strongly associated with significantly lower rates of postoperative pulmonary complications and surgical site infection, shorter length of stay, and significantly higher rates of R0 margin resections.ConclusionMinimally invasive pancreatoduodenectomy remains noninferior to open pancreatoduodenectomy for grade B/C postoperative pancreatic fistula but is strongly associated with significantly lower rates of postoperative pulmonary complications and surgical site infection. Minimally invasive pancreatoduodenectomy can be adopted safely with good outcomes irrespective of annual center resection volume. 相似文献
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Ghizlane Genc İlken Kocadereli Ferda Tasar Kamer Kilinc Sibel El Bahram Sarkarati 《Lasers in medical science》2013,28(1):41-47
The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the velocity of orthodontic tooth movement and (2) the nitric oxide levels in gingival crevicular fluid (GCF) during orthodontic treatment. The sample consisted of 20 patients (14 girls, six boys) whose maxillary first premolars were extracted and canines distalized. A gallium-aluminum-arsenide (Ga-Al-As) diode laser was applied on the day 0, and the 3rd, 7th, 14th, 21st, and 28th days when the retraction of the maxillary lateral incisors was initiated. The right maxillary lateral incisors composed the study group (the laser group), whereas the left maxillary lateral incisors served as the control. The teeth in the laser group received a total of ten doses of laser application: five doses from the buccal and five doses from the palatal side (two cervical, one middle, two apical) with an output power of 20 mW and a dose of 0.71 J /cm2. Gingival crevicular fluid samples were obtained on the above-mentioned days, and the nitric oxide levels were analyzed. Bonferroni and repeated measures variant analysis tests were used for statistical analysis with the significance level set at p ≤ 0.05. The application of low-level laser therapy accelerated orthodontic tooth movement significantly; there were no statistically significant changes in the nitric oxide levels of the gingival crevicular fluid during orthodontic treatment. 相似文献
9.
Hilal Bayram Halime Kenar Ferda Taşar Vasıf Hasırcı 《International journal of oral and maxillofacial surgery》2013,42(1):140-146
A limited number of clinical studies indicate the supportive role of low level laser therapy (LLLT) on medical and/or surgical approaches carried out in treatment modalities for bisphosphonate related necrosis of jaws (BRONJ), the most common side effect of bisphosphonates used to inhibit bone resorption. The purpose of this study was to investigate the effects of LLLT on cell proliferation and alkaline phosphatase (ALP) activity of human osteoblast-like cells (Saos-2) treated with different doses of zoledronate, the most potent bisphosphonate. Saos-2 cells were treated with different concentrations of zoledronate and were irradiated with diode laser (wavelength 808 nm, 10 s, 0.25 or 0.50 W). Cell numbers and ALP activity of the cells were determined. LLLT mildly increased the proliferation rate or ALP activity, while zoledronate reduced both. When applied together, LLLT lessened the detrimental effects of zoledronate and improved cell function and/or proliferation. Based on the results of this study, it was concluded that LLLT has biostimulative effects on Saos-2 cells, even after treatment with zoledronate. LLLT may serve as a useful supportive method for BRONJ treatment through enhancement of healing by osteoblasts. 相似文献
10.
Sait Demirkol M.D. Ugur Kucuk M.D. Oben Baysan M.D. Sevket Balta M.D. Turgay Celik M.D. Ibrahim Halil Kurt M.D. Hilal Olgun Kucuk M.D. Uygar Cagdas Yuksel M.D. Murat Unlu M.D. Mehmet Yokusoglu M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(9):1064-1070
Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle. 相似文献