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Said Saghieh Elie Ghanem Bernard Sagherian Maria Karam Nadim Afeiche 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2008,18(3):237-242
The treatment of open segmental tibia fracture associated with bone loss is very demanding. Despite the fact that the principles of the distraction osteogenesis are being followed commonly in these fractures, there is not a single technique that fits all situations. In this article, we report a case where the initial fractures were stabilized with a monolateral bridging external fixator with no evidence of callus formation 6 weeks later. The proximal fracture was used as “an osteotomy” for bone transport after a latent period of 6 weeks of compression. The successful outcome in this patient, confirms that distraction of a delayed union even when it is mobile, can lead to bone formation and healing of the delayed union. 相似文献
976.
S A M Said M B M Hofman A M Beek T van der Werf A C van Rossum 《Journal of cardiovascular magnetic resonance》2007,9(3):575-583
OBJECTIVE: To evaluate the use of cardiovascular magnetic resonance (CMR) to visualize angiographically-detected congenital coronary artery fistulas in adults. METHODS: CMR techniques were used to study 13 patients, recruited from the Dutch Registry, with previously angiographically diagnosed fistulas. RESULTS: Coronary fistulas were detected in 10 of 13 (77%) patients by CMR and, retrospectively, in two (92%) more. In 93% of these, it was possible to determine the origin and the outflow site of the fistulas. Cardiovascular magnetic resonance allowed demonstration of dilatation of the fistula-related coronary artery in all cases. Tortuosity of fistulas was detected in all visualized patients. Uni-or bilaterality of fistulas as seen on CAG was proven on CMR in all patients. Flow measurement could be performed in 8 patients. A fairly good correlation (r = 0.72) was found between angiographic (mean 6.2 mm, range 1-16) and cardiovascular magnetic resonance (mean 6.3 mm, range 3-15) measured fistulous diameters. CONCLUSIONS: Cardiovascular magnetic resonance of congenital fistulas with clinical significant shunting is feasible and can provide additional physiological data complementary to the findings of conventional coronary angiography. 相似文献
977.
The present study was conducted in Kohistan region, where mafic and ultramafic rocks (Kohistan island arc and Indus suture zone) and metasedimentary rocks (Indian plate) are exposed. Water samples were collected from the springs, streams and Indus river and analyzed for physical parameters, anions, cations and arsenic (As3+, As5+ and arsenic total). The water quality in Kohistan region was evaluated by comparing the physio-chemical parameters with permissible limits set by Pakistan environmental protection agency and world health organization. Most of the studied parameters were found within their respective permissible limits. However in some samples, the iron and arsenic concentrations exceeded their permissible limits. For health risk assessment of arsenic, the average daily dose, hazards quotient (HQ) and cancer risk were calculated by using statistical formulas. The values of HQ were found >1 in the samples collected from Jabba, Dubair, while HQ values were <1 in rest of the samples. This level of contamination should have low chronic risk and medium cancer risk when compared with US EPA guidelines. Furthermore, the inter-dependence of physio-chemical parameters and pollution load was also calculated by using multivariate statistical techniques like one-way ANOVA, correlation analysis, regression analysis, cluster analysis and principle component analysis. 相似文献
978.
Jered C Garrison Tammy L Rold Gary L Sieckman Said Daibes Figueroa Wynn A Volkert Silvia S Jurisson Timothy J Hoffman 《Journal of nuclear medicine》2007,48(8):1327-1337
The BB2 receptor subtype, of the bombesin family of receptors, has been shown to be highly overexpressed in a variety of human tumors, including prostate cancer. Bombesin (BBN), a 14-amino acid peptide, has been shown to target the BB2 receptor with high affinity. 64Cu (half-life = 12.7 h, beta+: 18%, E(beta+ max) = 653 keV; beta-: 37%, E(beta- max) = 578 keV) is a radioisotope that has clinical potential for application in both diagnostic imaging and radionuclide therapy. Recently, new chelation systems such as 1,4,8,11-tetraazabicyclo[6.6.2]hexadecane-4,11-diacetic acid (CB-TE2A) have been reported to significantly stabilize the 64Cu radiometal in vivo. The increased stability of the 64Cu-CB-TE2A chelate complex has been shown to significantly reduce nontarget retention compared with tetraazamacrocycles such as 1,4,7,10-tetraazacyclodoadecane-N,N',N',N'-tetraacetic acid (DOTA). The aim of this study was to determine whether the CB-TE2A chelation system could significantly improve the in vivo stability of 64Cu bombesin analogs. The study directly compares 64Cu bombesin analogs using the CB-TE2A and DOTA chelation systems in a prostate cancer xenograft SCID (severely compromised immunodeficient) mouse model. METHODS: The CB-TE2A-8-AOC-BBN(7-14)NH2 and DOTA-8-AOC-BBN(7-14)NH2 conjugates were synthesized and radiolabeled with 64Cu. The receptor-binding affinity and internalization profile of each metallated conjugate was evaluated using PC-3 cells. Pharmacokinetic and small-animal PET/CT studies were performed using female SCID mice bearing PC-3 xenografts. RESULTS: In vivo BB2 receptor targeting was confirmed by tumor uptake values of 6.95 +/- 2.27 and 4.95 +/- 0.91 %ID/g (percentage injected dose per gram) at the 15-min time point for the 64Cu-CB-TE2A and 64Cu-DOTA radioconjugates, respectively. At the 24-h time point, liver uptake was substantially reduced for the 64Cu-CB-TE2A radioconjugate (0.21 +/- 0.06 %ID/g) compared with the 64Cu-DOTA radioconjugate (7.80 +/- 1.51 %ID/g). The 64Cu-CB-TE2A-8-AOC-BBN(7-14)NH2 radioconjugate demonstrated significant clearance, 98.60 +/- 0.28 %ID, from the mouse at 24 h after injection. In contrast, only 67.84 +/- 5.43 %ID of the 64Cu activity was excreted using the 64Cu-DOTA-8-AOC-BBN(7-14)NH2 radioconjugate because of nontarget retention. CONCLUSION: The pharmacokinetic and small-animal PET/CT studies demonstrate significantly improved nontarget tissue clearance for the 64Cu-CB-TE2A8-AOC-BBN(7-14)NH2. This is attributed to the improved in vivo stability of the 64Cu-CB-TE2A chelate complex as compared with the 64Cu-DOTA chelate complex. 相似文献
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980.
Valerie Amiard MD Hugues Jullien PhD Dia Nassif MD Veronique Bach PhD Yves Maingourd MD Said Ahmaidi PhD 《Congenital heart disease》2008,3(3):191-199
The present investigation was aimed at assessing the effect of home‐based training on cardiorespiratory responses in children surgically corrected for congenital heart impairment using dyspnea threshold (DT) as training intensity. A group of 23 children aged 15 ± 1.4 years who had undergone surgical correction for congenital heart disease (CHD group) and 12 healthy children used as a control group performed an exercise protocol during which aerobic capacity, ventilatory threshold (VT), and DT were assessed. Afterwards, the CHD group was divided into two subgroups: trained and untrained subjects. Training sessions over a period of 2 months were performed at an intensity corresponding to DT by the CHD trained group. Dyspnea was scored according to a visual analog scale during the warm up, at each exercise stage, and during the recovery period. DT was located on the oxygen uptake/dyspnea curve when a sudden increase in the dyspnea score occured, while VT was defined according to the methodology previously employed by Beaver and colleagues. The results showed that children who had undergone surgery for CHD had reduced aerobic capacity. No significant difference was observed between VT and DT in children corrected for CHD. These two thresholds were highly related. Home‐based training at DT did not strongly improve aerobic capacity nor did it influence the relationship between VT and DT. Further studies should be conducted to confirm these preliminary findings, particularly when aerobic capacity is improved by training. 相似文献