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61.
62.
The effect of two configuration factors,time, and thermal cycling on resin to dentin bond strengths 总被引:2,自引:0,他引:2
Most in vitro testing of bonding systems is performed using specimens made in a mold with a low configuration (C) factor (ratio of bonded/unbonded surfaces) whereas clinically the C-factor is usually much greater. This study compared the effect of thermal cycling on the measured shear bond strength of 3M Single Bond dental adhesive bonded to dentin using molds with two different C-factors. The hypothesis was that neither C-factor nor thermal cycling would affect measured bond strengths. Resin composite was bonded to human dentin in cylindrical molds with an internal diameter of 3.2mm and either 1mm or 2.5mm deep. The 1mm deep molds had a C-factor of 2.2 and the 2.5mm deep molds had a C-factor of 4.1. Specimens were debonded either 10min after they had been bonded to dentin, or after they had been stored for 7 days in water at 37+/-1 degrees C, or after thermal cycling 5000 times for 7 days. Two-way ANOVA showed that overall both the C-factor and the storage condition had a significant effect on bond strength (p<0.001). There was a significant interaction (p<0.001) between the C-factor and how the specimens had been stored. The GLM/LSMEANS procedure with Sidak's adjustment for multiple comparisons showed that overall the specimens made in the mold with a high C-factor (4.1) had a lower bond strength than those that had been made in the mold with a lower (2.2) C-factor (p<0.001). Thermal cycling had a negative effect on the bond strength only for specimens made in molds with a C-factor of 4.1 (p<0.001). 相似文献
63.
Ramirez JI Vassiliu P Gonzalez-Ruiz C Vukasin P Ortega A Kaiser AM Beart RW 《The American surgeon》2003,69(11):941-945
The American Society of Colorectal Surgeons (ASCRS) recently endorsed low-molecular-weight heparin and low-dose heparin as primary prophylaxis for venous thromboembolism (VTE) in highest-risk patients. Our study evaluates the feasibility of sequential compression device (SCD) use for VTE prophylaxis in these patients. Computerized databases of discharge diagnoses from three hospitals were reviewed. All patients with colorectal cancer or inflammatory bowel disease during a 7-year period were identified. Those who underwent major abdominal surgery and received VTE prophylaxis exclusively with SCDs were selected for the study. Patients diagnosed with postoperative VTE were identified through review of the three databases and of patient records for 90 days after surgery. One thousand two hundred eighty-one patients classified as highest-risk under the published ASCRS parameters underwent major abdominal surgery and received SCDs perioperatively. The incidence of clinically detectable postoperative VTE was 0.78 per cent. There were trends toward lower incidence among patients with malignancy (0.53%) compared with inflammatory bowel disease (1.48%, P = 0.09), and those with abdominal compared to pelvic procedures (0.62% vs. 1.04%, P = 0.41). Prophylaxis for perioperative VTE solely with SCD is a viable option for patients classified as highest-risk under ASCRS parameters. 相似文献
64.
Athanassiou H Antonadou D Coliarakis N Kouveli A Synodinou M Paraskevaidis M Sarris G Georgakopoulos GR Panousaki K Karageorgis P Throuvalas N;Oncology Hellenic Group 《International journal of radiation oncology, biology, physics》2003,56(4):1154-1160
PURPOSE: To evaluate whether pretreatment with amifostine can reduce treatment-induced toxicity in patients with pelvic malignancies undergoing radiotherapy (RT). METHODS AND MATERIALS: A total of 205 patients with pelvic malignancies (rectal, 32; bladder, 47; prostate, 40; gynecologic, 86) were randomized to receive RT (Group 1, n = 95) or RT plus amifostine (Group 2, n = 110). The patient characteristics for both treatment groups were well balanced. Amifostine was administered at 340 mg/m(2) i.v., 15 min before RT, with standard antiemetics 30 min before. All patients received conventional RT, radical (65-70 Gy) or postoperative (50 Gy), with 45 Gy given to the whole pelvis at daily fractions of 1.8-2.0 Gy, 5 d/wk. Skin, bowel, bladder, and hematologic toxicities were evaluated according to the Radiation Therapy Oncology Group/European Organization Research and Treatment of Cancer scoring system. RESULTS: A significant reduction occurred in acute Grade 2-3 bladder and lower GI tract toxicities in the amifostine group (p <0.05, Weeks 3-7). With a median follow-up of 12 months, few late Grade 2-3 effects were observed in either group. No statistically significant difference between the two groups was observed in terms of response 6 weeks after RT completion (complete response plus partial response, 96.8% in the control and 98.3% in the amifostine arm). Amifostine was well tolerated, with only moderate hypotension occurring in 2 patients and moderate nausea in 1 patient. CONCLUSIONS: The results of this randomized trial support the role of amifostine in reducing acute radiation-related toxicity of the bladder and lower GI tract in patients with pelvic malignancies, without evidence of tumor protection. 相似文献
65.
Efstathios J. Boviatsis Lampis C. Stavrinou Andreas T. Kouyialis Maria M. Gavra Pantelis C. Stavrinou Marios Themistokleous Panayiotis Selviaridis Damianos E. Sakas 《European spine journal》2008,17(6):831-837
This study is designed based on the retrospective analysis of patients treated in the Neurosurgical Department of two major
hospitals and review of the literature. The aim of this study is to evaluate the efficacy of surgery and address controversial
issues in the treatment of symptomatic lumbar intraspinal synovial cysts. Spinal juxtafacet cysts (synovial and ganglion cysts)
are a rare cause of low back and radicular leg pain. Although the relevant reports in the international literature are increasing,
the controversy about conservative versus surgical treatment and the need for concomitant fusion still exists. Data from seven
patients (age range 58–69 years, mean age 61 years) with low back and radicular leg pain due to a lumbar facet joint cyst
were retrospectively analyzed. Demographic data, cyst level, presence of concomitant local pathology, treatment and results
of treatment were recorded. A follow-up of at least 6 months (range 6–48 months) was conducted and results were noted. All
patients had back pain, while five also experienced unilateral radicular leg pain and one had bilateral leg pain. One patient
had neurogenic claudication. MRI identified the cyst and highlighted underlying pathology in all cases. All patients underwent
surgical cyst excision. No fusion was performed. Post-operatively, all patients showed a total resolution of symptoms with
sustained benefit at final evaluation. Review of the literature revealed a trend towards surgery, as this is correlated to
a more favorable outcome compared with conservative treatment. Fusion should be performed on a case-by-case basis only. Surgery
is a safe and effective treatment choice in this increasingly appearing ailment. A prospective, randomized trial should clarify
issues under debate.
An erratum to this article can be found at 相似文献
66.
Liappas IA Nicolaou C Chatzipanagiotou S Tzavellas EO Piperi C Papageorgiou C Boufidou F Bagos P Soldatos CR 《Clinical biochemistry》2007,40(11):781-786
Alcohol abuse is a major cause of liver cirrhosis as well as chronic liver disease. The aim of the present study was to investigate the possible correlation, between liver dysfunction biological markers and vitamin B12, with interleukin-6, in the serum of alcohol-dependent individuals without liver disease (AWLD). In a sample of 43 alcohol abusing/dependent subjects (33 males and 10 females) treated on an inpatient basis according to a standard detoxification protocol, the serum activities of the hepatic enzymes (ASAT, ALAT, gamma-GT), as well as the concentration of B12 and IL-6, were determined on admission. A strong positive correlation has been observed between IL-6 and B12, ASAT, ALAT, and gamma-GT at the beginning of the detoxification period. The results confirmed that in alcohol-dependent individuals, the median serum concentration of IL-6, before the beginning of the treatment, had a significant positive correlation with the liver dysfunction biological markers and B12. In conclusion, IL-6 might be used as an additional diagnostic marker for the degree of liver dysfunction in alcohol dependent individuals. 相似文献
67.
Dimitris Siablis Pantelis Kraniotis Dimitris Karnabatidis George C Kagadis Konstantinos Katsanos John Tsolakis 《Journal of endovascular therapy》2005,12(6):685-695
PURPOSE: To report the 6-month angiographic results from a prospective single-center study investigating the efficacy and outcome of sirolimus-eluting stents used for bailout after infrapopliteal revascularization of patients with critical limb ischemia (CLI). METHODS: Twenty-nine patients (21 men; mean age 68.7 years) underwent infrapopliteal revascularization with bare metal stents (group B) implanted for bailout in 65 lesions (38 stenoses and 27 occlusions) in 40 infrapopliteal arteries. Another 29 patients (21 men; mean age 68.8 years) underwent infrapopliteal bailout stenting with sirolimus-eluting stents (group S) in 66 lesions (46 stenoses and 20 occlusions) in 41 vessels. Preliminary 6-month angiographic and clinical results were analyzed. RESULTS: Hyperlipidemia and symptomatic cardiac and carotid diseases were more pronounced in group S (p<0.05). Technical success was 96.6% (28/29 limbs) in group B versus 100.0% in group S (p=0.16). Six-month primary patency was 68.1% in group B versus 92.0% in group S (p<0.002). Binary in-stent and in-segment restenosis rates were 55.3% and 66.0%, respectively, in patients with bare stents versus 4.0% and 32.0%, respectively, in patients treated with the sirolimus-eluting stents (both p<0.001). The target lesion re-intervention rate at 6 months was 17.0% in group B versus 4.0% in group S (p=0.02). Limb salvage was 100% in both groups. Six-month mortality and minor amputation rates were 6.9% and 17.2%, respectively, in group B versus 10.3% and 3.4%, respectively, in group S (p=0.32 and p=0.04, respectively). CONCLUSIONS: Sirolimus-eluting stents seem to restrict neointimal hyperplasia in the infrapopliteal vascular bed. 相似文献
68.
Ian H Harding Nadia Solowij Ben J Harrison Michael Takagi Valentina Lorenzetti Dan I Lubman Marc L Seal Christos Pantelis Murat Yücel 《Neuropsychopharmacology》2012,37(8):1923-1933
The long-term effect of regular cannabis use on brain function underlying cognitive control remains equivocal. Cognitive control abilities are thought to have a major role in everyday functioning, and their dysfunction has been implicated in the maintenance of maladaptive drug-taking patterns. In this study, the Multi-Source Interference Task was employed alongside functional magnetic resonance imaging and psychophysiological interaction methods to investigate functional interactions between brain regions underlying cognitive control. Current cannabis users with a history of greater than 10 years of daily or near-daily cannabis smoking (n=21) were compared with age, gender, and IQ-matched non-using controls (n=21). No differences in behavioral performance or magnitude of task-related brain activations were evident between the groups. However, greater connectivity between the prefrontal cortex and the occipitoparietal cortex was evident in cannabis users, as compared with controls, as cognitive control demands increased. The magnitude of this connectivity was positively associated with age of onset and lifetime exposure to cannabis. These findings suggest that brain regions responsible for coordinating behavioral control have an increased influence on the direction and switching of attention in cannabis users, and that these changes may have a compensatory role in mitigating cannabis-related impairments in cognitive control or perceptual processes. 相似文献
69.
70.
Chatzigeorgiou KS Sergentanis TN Tsiodras S Hamodrakas SJ Bagos PG 《Journal of clinical microbiology》2011,49(9):3284-3291
Phoenix 100 and Vitek 2 (operating with the current colorimetric cards) are commonly used in hospital laboratories for rapid identification of microorganisms. The present meta-analysis aims to evaluate and compare their performance on Gram-positive and Gram-negative bacteria. The MEDLINE database was searched up to October 2010 for the retrieval of relevant articles. Pooled correct identification rates were derived from random-effects models, using the arcsine transformation. Separate analyses were conducted at the genus and species levels; subanalyses and meta-regression were undertaken to reveal meaningful system- and study-related modifiers. A total of 29 (6,635 isolates) and 19 (4,363 isolates) articles were eligible for Phoenix and colorimetric Vitek 2, respectively. No significant differences were observed between Phoenix and Vitek 2 either at the genus (97.70% versus 97.59%, P = 0.919) or the species (92.51% versus 88.77%, P = 0.149) level. Studies conducted with conventional comparator methods tended to report significantly better results compared to those using molecular reference techniques. Speciation of Staphylococcus aureus was significantly more accurate in comparison to coagulase-negative staphylococci by both Phoenix (99.78% versus 88.42%, P < 0.00001) and Vitek 2 (98.22% versus 91.89%, P = 0.043). Vitek 2 also reached higher correct identification rates for Gram-negative fermenters versus nonfermenters at the genus (99.60% versus 95.90%, P = 0.004) and the species (97.42% versus 84.85%, P = 0.003) level. In conclusion, the accuracy of both systems seems modified by underlying sample- and comparator method-related parameters. Future simultaneous assessment of the instruments against molecular comparator procedures may facilitate interpretation of the current observations. 相似文献