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51.

Background  

Although the application of damage control surgery for trauma has been widely reported and defined, similar approach in non-trauma patients has not been well detailed.  相似文献   
52.
The integrin alpha v beta3 receptor is upregulated on tumor cells and endothelium and plays important roles in angiogenesis and metastasis. Arg-Gly-Asp (RGD) peptide ligands have high affinity for these integrins and can be radiolabeled for PET imaging of angiogenesis or tumor development. We have assessed the safety, stability, and tumor distribution kinetics of a novel radiolabeled RGD-based integrin peptide-polymer conjugate, 18F-AH111585, and its feasibility to detect tumors in metastatic breast cancer patients using PET. METHODS: The biodistribution of 18F-AH111585 was assessed in 18 tumor lesions from 7 patients with metastatic breast cancer by PET, and the PET data were compared with CT results. The metabolic stability of 18F-AH111585 was assessed by chromatography of plasma samples. Regions of interest (ROIs) defined over tumor and normal tissues of the PET images were used to determine the kinetics of radioligand binding in tissues. RESULTS: The radiopharmaceutical and PET procedures were well tolerated in all patients. All 18 tumors detected by CT were visible on the 18F-AH111585 PET images, either as distinct increases in uptake compared with the surrounding normal tissue or, in the case of liver metastases, as regions of deficit uptake because of the high background activity in normal liver tissue. 18F-AH111585 was either homogeneously distributed in the tumors or appeared within the tumor rim, consistent with the pattern of viable peripheral tumor and central necrosis often seen in association with angiogenesis. Increased uptake compared with background (P = 0.002) was demonstrated in metastases in lung, pleura, bone, lymph node, and primary tumor. CONCLUSION: 18F-AH111585 designed to bind the alpha v beta3 integrin is safe, metabolically stable, and retained in tumor tissues and detects breast cancer lesions by PET in most anatomic sites.  相似文献   
53.
Our goal was to determine the primary stability of overlapping osteochondral grafts used in mosaicplasty by studying the effect of overlapping in an ex vivo model. Osteochondral grafts, 10 mm in diameter, were transplanted from the trochlea of cow femurs to the weight-bearing area of the lateral femoral condyle with 0, 15, or 30% overlap. The grafts were pushed in with a probe at a rate of 2 mm/min, and load (N)-displacement (mm) curves were recorded. In Group I (control, 0% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 572.3 +/- 273.6 and 999.3 +/- 427.6 N, respectively. In Group II (15% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 263.6 +/- 91.7 and 746.6 +/- 88.0 N, respectively. In Group III (30% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 179.4 +/- 31.2 and 657.0 +/- 106.5 N, respectively. The loads that were necessary to produce a 1-mm dent in the grafts were significantly different between Groups I and II and Groups I and III (p < 0.05). These results suggest that stability may be reduced by graft overlapping in mosaicplasty surgery. The results of this ex vivo animal study contribute to a more complete understanding of the primary stability of osteochondral grafts in an overlapping position as well as postoperative protocols.  相似文献   
54.
Kaya RA  Türkmenoğlu O  Dalkiliç T  Aydin Y 《Neurosurgery》2003,53(5):1230-3; discussion 1233-4
OBJECTIVE AND IMPORTANCE: A spinal cord tumor occurring in association with Klippel-Feil syndrome is quite rare. The removal of an anteriorly located spinal cord tumor at the level of block vertebrae creates a surgical challenge. CLINICAL PRESENTATION: A case of an intradural extramedullary dermoid cyst located anterior to the spinal cord and a syringomyelic cavity at the level of block vertebrae in a 43-year-old woman with Klippel-Feil syndrome is presented. She experienced pain and numbness in both shoulders and in her neck, and she had a slight weakness in both arms before the operation. Her weakness and the clinical symptoms completely disappeared after the operation, and the resolution of the syringomyelic cavity was observed at control magnetic resonance imaging. INTERVENTION: An anterior approach creating a fenestra corpectomy to the block vertebrae was performed, and the tumor was removed totally. No fusion or fixation was performed. CONCLUSION: To our knowledge, this is the first report of an anteriorly located intradural extramedullary cervical spine tumor in association with Klippel-Feil syndrome treated with this surgical technique. A three-dimensional computed tomographic control scan obtained 1 year after the operation did not show any instability.  相似文献   
55.
Methods: Second primary cancers constitute approximately 9–10% of malignancies diagnosed in the United States. We aimed to show the risk and incidance of second primary tumor occuring associated to urologic tumors and show the distrubution of tumors in Tracia region. We retrospectively examined the patients' files with the diagnosis of malignant disease between the years 1985–2000. Hazard function analysis was performed to estimate the relative risk of secondary malignancy occuring. Age, sex and tumor number were examined to find out if they affect on mortality rate. Results: A total number of 25 MPMNs were diagnosed. In 52 percent of the cases the second primary neoplasm developed within six months. The relative risk of development of a second neoplasm is found as increasing 1.111 times per month. The incidence of secondary malignancy occuring in the patients with one tumor was found as 6.31%. Age (p < 0.001) and tumor number (p < 0.001) are found as statistically effective predictor on mortality rate where the sex is not. Conclusions: In the patients with a primary tumor not only the metastasis must be investigated but also second primary tumors should be taken in to consideration. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
56.

Objectives:

To compare the mean total antioxidant status (TAS) among 3 glaucoma types, namely: pseudoexfoliation glaucoma (PEG), primary open angle glaucoma (POAG), and primary angle closure glaucoma (PACG), and study its potential association with various clinical glaucoma-parameters.

Methods:

In this case-control study, plasma samples were obtained between September 2013 and October 2014 from 340 glaucoma patients (PEG [n=54]; POAG [n=147]; PACG [n=139]), and 351 controls of matching age, gender, ethnicity, and 5 different systemic co-morbidities from King Abdulaziz University Hospital, Riyadh, Saudi Arabia. The TAS in all samples was determined by a colorimetric-based assay.

Results:

The mean±standard deviation of TAS was significantly lower among cases: 0.77±0.32 than controls: 1.1±0.22, p<0.0001. Moreover, the TAS levels were significantly different across the 3 types of glaucoma: 0.86±0.24 in PEG, 0.47±0.32 in POAG, and 0.98±0.41 in PACG (all p<0.0001). In addition, there was a significant correlation between TAS and age at onset (Pearson correlation coefficient [R] 0.17, p<0.0001), cup/disc ratio (R: -0.13, p=0.004), and number of anti-glaucoma medications (R: -0.16, p=0.001).

Conclusion:

Our findings provide evidence that plasma TAS levels are decreased in patients with glaucoma, more so in POAG and PEG than PACG, supporting the hypothesis that decreased antioxidative defense and/or increased oxidative stress may have a critical role in the pathogenesis of glaucoma.Glaucoma is a progressive optic neuropathy associated with optic nerve damage, and is one of the most leading cause of blindness worldwide.1 Elevated intraocular pressure (IOP) as a result of reduction in normal aqueous outflow is a major causal risk factor that is well supported by animal studies.2-4 Although IOP is considered a major risk factor for glaucoma,2,3 other concomitant factors affecting the pathophysiology of glaucomatous retinal ganglion cell (RGC) death include retinal ischemia,5 nutritional status,6 and oxidative stress.7 There is evidence of oxidative damage in ocular diseases, such as cataract and age-related macular degeneration.8 In addition, significant oxidative damage has been demonstrated in human trabecular meshwork (TM) cells of patients with glaucoma,7 causing elevated IOP and visual field damage.9 Furthermore, our previous studies have documented mitochondrial abnormalities10-12 (oxidative stress marker), and glutathione-S-transferase (antioxidant) gene (GST) polymorphisms to be associated with various types of glaucoma.13 It is clearly evident from the literature, and our own studies, that oxidative stress mechanisms play a critical role in the pathogenesis of glaucoma. Previous studies had demonstrated reduced total antioxidant capacity in aqueous humor and blood samples from patients with glaucoma.14-17 To evaluate the role of oxidative stress in different types of glaucoma we had previously investigated total antioxidants status (TAS) in the plasma of pseudoexfoliation glaucoma (PEG) patients,18 primary angle closure glaucoma (PACG) patients,19 and in the plasma of primary open angle glaucoma (POAG) patients.20 As an extension to these studies, here, we compare the mean TAS level among these 3 glaucoma types, and study the potential association between the TAS level and various clinical parameters important to each type of glaucoma.18-20  相似文献   
57.
Background Pneumoperitoneum causes intracranial pressure elevation and blood stasis at lower extremities. This study investigates cerebral oxygen saturation changes during laparoscopy and the effects of intermittent sequential compression (ISC) of the lower extremities in patients during elective laparoscopic cholecystectomy. Patients and method Sixty patients were randomly divided into two groups according to the application of ISC to the lower extremities. Group I served as control group whereas ISC was applied to group II. Cerebral oxygen saturation, peripheral blood oxygen saturation, heart rate, mean blood pressure, and associated changes have been recorded during the operation. Results Peripheral blood oxygen saturation and mean blood pressure values did not change significantly after pneumoperitoneum. Cerebral oxygen saturation levels of the group II patients were higher in than the group I patients and the difference between the groups was statistically significant (p = 0.0001). The difference became more prominent following the 35th minute of the operation. Mean heart rate of the patients in group II was lower than the patients in group I and the difference was also statistically significant (p = 0.0001). Conclusion In this study, it was found that the decrease in cerebral oxygen saturation was recovered with ISC application. This simple and reliable technique helps to restore cerebral oxygen saturation levels while increasing blood return from the lower extremities.  相似文献   
58.
BACKGROUND: The effects on morbidity were examined of providing an educational intervention and a written guided self-management plan to the parents of pre-school children following a recent attendance at hospital for asthma or wheeze. METHODS: A prospective, randomised, partially blinded, controlled trial was designed at two secondary care centres. Over a 13 month period 200 children aged 18 months to 5 years at the time of admission to a children's ward or attendance at an accident and emergency department or children's (emergency) assessment unit (A&E/CAU) with a primary diagnosis of acute severe asthma or wheezing were recruited. 101 children were randomised into the control group and received usual care and 99 were assigned to the intervention group and received: (1) a pre-school asthma booklet; (2) a written guided self-management plan; and (3) two 20 minute structured educational sessions between a specialist respiratory nurse and the parent(s) and child. Subjects were assessed at 3, 6, and 12 months. The main outcomes were GP consultation rates, hospital re-admissions, and attendances at A&E/CAU. Secondary outcomes included disability score, caregivers' quality of life, and parental knowledge of asthma. RESULTS: There were no statistically significant differences between the two groups during the 12 month follow up period for any of the main or secondary outcome measures. CONCLUSIONS: These results do not support the hypothesis that the introduction of an educational package and a written guided self-management plan to the parents of pre-school children with asthma who had recently attended hospital for troublesome asthma or wheeze reduces morbidity over the subsequent 12 months.  相似文献   
59.
INTRODUCTION: Choosing surgery as a career is declining among U.S. medical students. The 8-wk third year surgery clerkship at our institution can be an intense learning experience, and we hypothesized that during this clerkship medical student quality-of-life would drop significantly from baseline, and that this drop would be greater among certain subgroups, such as women students not interested in pursuing a surgical career, and those who place a high value on a controllable lifestyle. METHODS: At clerkship orientation (baseline), students were asked to complete a survey that measured quality-of-life on an 84-point scale, and depression on a 40-point scale. The quality-of-life scale was composed of select questions from the Medical Outcomes Study, and the Harvard Department of Psychiatry/NDSD brief screening instrument was used to measure depression. Students were also asked the typical number of hours they slept per night. Demographics, attitude toward a controllable lifestyle, and top three specialties of interest were also gathered at baseline. On week 6 of the clerkship, students were surveyed on the same quality-of -life and depression scales, and asked average hours of sleep per night for the previous week. RESULTS: From June 2005 through December 2006, 143 of 177 (81%) students agreed to participate, and after exclusions for missing data, 137 students were included in the analysis. Sixty-nine students were women (51%), and the average age was 25.8 (sd 2.6). Mean quality-of-life at baseline was 57.0 (sd 11.3) and at week 6 was 50.4 (sd 10.1) representing a statistically significant average decline of 6.6 points (P < 0.0001). Mean depression at baseline was 14.4 (sd 3.8) and at week 6 was 15.1 (sd 3.6), representing a small but significant average decline of 0.7 points (P = 0.0155). Mean sleep at baseline was 6.3 h/night (sd 0.9) and at week 6 was 5.7 h/night (sd 1.2), representing a statistically significant average decline of 0.6 h/night (P < 0.0001). Declines were similar on all outcomes between men versus women, those who ranked surgery in their top three career choices versus those who did not, and those who ranked controllable lifestyle as "very important" versus all other categories. CONCLUSION: Quality-of-life and sleep declines and depression increases significantly in third-year medical students from orientation to week 6 of their surgery clerkship at our institution. We look forward to studying quality-of-life on other clerkships for comparison, assessing whether the magnitude of this decline in quality-of-life predicts students avoiding a future career in surgery, and testing interventions to prevent this decline in quality-of-life during the clerkship.  相似文献   
60.
PURPOSE: The purpose of this study was to evaluate the treatment of patients with Mason type III radial head fracture with and without elbow dislocation by open reduction with internal fixation, collateral ligament repair, and early mobilization. An additional purpose was to investigate whether there is any effect of elbow dislocation on the severity and functional outcome. METHODS: Twenty-five patients were treated with open reduction with internal fixation using low-profile miniplate and screws for comminuted fracture of the radial head. Eighteen fractures were Mason type III, and 7 fractures were Mason type III with elbow dislocation. There were 5 women and 20 men with a mean age of 34 years. The mean follow-up time was 27 months. Patients were reviewed for functional ability, physical examination, and radiographic assessment. RESULTS: The mean functional index in Mason type III fracture and Mason type III fracture with elbow dislocation was 87 for both groups. The mean range of motion at the elbow joint was calculated as 5 degrees extension to 136 degrees flexion for Mason type III and 7 degrees extension to 133 degrees flexion for Mason type III with elbow dislocation. The mean pronation and supination for all patients were 74 degrees and 67 degrees , respectively. CONCLUSIONS: Selected Mason III radial head fractures and fracture dislocations could be stabilized satisfactorily with internal fixation. Meticulous surgical technique, combined with rigid internal fixation, can allow early motion of the forearm and elbow after fixation of Mason type III radial head fractures with and without elbow dislocation and ligamentous injury. We believe there is still a role for prosthetic replacement in comminuted Mason III radial head fractures that cannot reliably be treated with open reduction and internal fixation. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.  相似文献   
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