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41.
Rachel M Massey Oliver J Warren Michal Szczeklik Sophie Wallace Daniel R Leff John Kokotsakis Ara Darzi Thanos Athanasiou 《Journal of cardiothoracic surgery》2007,2(1):26-9
The use of a skeletonized internal thoracic artery in coronary artery bypass graft surgery has been shown to confer certain
advantages over a traditional pedicled technique, particularly in certain patient groups. Recent reports indicate that radial
and gastroepiploic arteries can also be harvested using a skeletonized technique. The aim of this study is to systematically
review the available evidence regarding the use of skeletonized radial and gastroepiploic arteries within coronary artery
bypass surgery, focusing specifically on it's effect on conduit length and flow, levels of endothelial damage, graft patency
and clinical outcome. Four electronic databases were systematically searched for studies reporting the utilisation of the
skeletonization technique within coronary revascularisation surgery in humans. Reference lists of all identified studies were
checked for any missing publications. There appears to be some evidence that skeletonization may improve angiographic patency,
when compared with pedicled vessels in the short to mid-term. We have found no suggestion of increased complication rates
or increased operating time. Skeletonization may increase the length of the conduit, and the number of sequential graft sites,
but no clear clinical benefits are apparent. Our study suggests that there is not enough high quality or consistent evidence
to currently advocate the application of this technique to radial or gastroepiploic conduits ahead of a traditional pedicled
technique. 相似文献
42.
Christophe Doddoli Adrian Aragon Fabrice Barlesi Bruno Chetaille Stéphane Robitail Roger Giudicelli Pierre Fuentes Pascal Thomas 《European journal of cardio-thoracic surgery》2005,27(4):680-685
OBJECTIVE: To assess the therapeutic effect of the extent of lymph node dissection performed in patients with a stage pI non-small-cell lung cancer (NSCLC). METHODS: We analysed data on 465 patients with stage I NSCLC who were treated with surgical resection and some form of lymph node sampling. The median number of lymph node sampled was 10 and the median number of ipsilateral mediastinal lymph node stations sampled was two. We chose to define a procedure that harvested 10 or more lymph nodes and sampled two or more ipsilateral mediastinal stations as a lymphadenectomy, by contrast with sampling when one or both criteria were not satisfied. The effect of the surgical techniques: lymph node sampling (LS; n=207) vs. lymphadenectomy (LA; n=258) on 30-day mortality and overall survival were investigated. RESULTS: A total of 6244 lymph nodes was examined, including 4306 mediastinal lymph nodes. The mean (+/-SD) numbers of removed lymph nodes were 7+/-6.1 per patient following LS vs.18.6+/-9.3 following LA (P=0.001). An average mean of 1+/-0.90 mediastinal lymph node station per patient was sampled following LS vs. 2.7+/-0.8 following LA (P<10(-6)). Overall 30-day mortality rates were 2.4 and 3.1%, respectively. LA was disclosed as a favourable prognosticator at multivariate analysis (Hazard Risk: 1.43; 95% Confidence Interval: 1.00-2.04; P=0.048), together with younger patient age, absence of blood vessels invasion, and smaller tumour size. CONCLUSIONS: Importance of lymph node dissection affects patients outcome, while it does not enhance the operative mortality. A minimum of 10 lymph nodes assessed, and two mediastinal stations sampled are suggested as possible pragmatic markers of the quality of lymphadenectomy. 相似文献
43.
Background
Studies have found that deaf individuals have higher rates of psychiatric disorder than those who are hearing, while at the same time encountering difficulties in accessing mental health services. These factors might increase the risk of suicide. However, the burden of suicidal behaviour in deaf people is currently unknown. 相似文献44.
Carsten Olbrich Andrea Gessner Werner Schr?der Oliver Kayser Rainer H Müller 《Journal of controlled release》2004,96(3):425-435
Sleeping sickness is a widely distributed disease in great parts of Africa. It is caused by Trypanosoma brucei gambiense and rhodiense, transmitted by the Tse-Tse fly. After a hemolymphatic stage, the parasites enter the central nervous system where they cannot be reached by hydrophilic drugs. To potentially deliver the hydrophilic antitrypanosomal drug diminazene diaceturate to the brain of infected mice, the drug was formulated as lipid-drug conjugate (LDC) nanoparticles (NP) by combination with stearic- (SA) and oleic acid (OA). To estimate the in vivo compatibility, the particles were incubated with human granulocytes. Because as potential delivery mechanism the absorption of specific serum proteins (ApoE, Apo AI and Apo AIV) was found to be responsible for the delivery of nanoparticles to the brain, demonstrated using PBCA nanoparticles coated with polysorbate 80 (LDL uptake mechanism) the nanoparticles were incubated with mouse serum and the adsorption pattern was determined using the 2-D PAGE technique. As a result of this study, the cytotoxic potential was shown to decrease when diminazene is part of the particle matrix compared to pure fatty acid nanoparticles and the mouse serum protein adsorption pattern differs from the samples studied earlier in human serum. Especially, the fact concerning Apo-E that could be detected when the particles were incubated in human serum is absent after the mouse serum incubation, potentially, is a critical point for the delivery via the LDL-uptake mechanism but the data demonstrate that LDC nanoparticles, with 33% (wt/wt) drug loading capacity possess the potential to act as a delivery system for hydrophilic drugs like diminazene diaceturate and that further studies have to demonstrate the usability as a brain delivery system. 相似文献
45.
Comparative in vivo evaluation of technetium and iodine labels on an anti-HER2 affibody for single-photon imaging of HER2 expression in tumors. 总被引:1,自引:0,他引:1
Anna Orlova Fredrik Y Nilsson Maria Wikman Charles Widstr?m Stefan St?hl J?rgen Carlsson Vladimir Tolmachev 《Journal of nuclear medicine》2006,47(3):512-519
In vivo diagnosis with cancer-specific targeting agents that have optimal characteristics for imaging is an important development in treatment planning for cancer patients. Overexpression of the HER2 antigen is high in several types of carcinomas and has predictive and prognostic value, especially for breast cancer. A new type of targeting agent, the Affibody molecule, was described recently. An Affibody dimer, His6-(ZHER2:4)2 (15.4 kDa), binds to HER2 with an affinity of 3 nmol/L and might be used for the imaging of HER2 expression. The use of 99mTc might improve the availability of the labeled conjugate, and Tc(I)-carbonyl chemistry enables the site-specific labeling of the histidine tag on the Affibody molecule. The goals of the present study were to prepare 99mTc-labeled His6-(ZHER2:4)2 and to evaluate its targeting properties compared with the targeting properties of 125I-4-iodobenzoate-His6-(ZHER2:4)2 [125I-His6-(ZHER2:4)2]. METHODS: The labeling of His6-(ZHER2:4)2 with 99mTc was performed with an IsoLink kit. The specificity of 99mTc-His6-(ZHER2:4)2 binding to HER2 was evaluated in vitro with SK-OV-3 ovarian carcinoma cells. The comparative biodistributions of 99mTc-His6-(ZHER2:4)2 and 125I-His6-(ZHER2:4)2 in tumor-bearing BALB/c nu/nu mice were determined. RESULTS: The labeling yield for 99mTc-His6-(ZHER2:4)2 was approximately 60% (50 degrees C), and the radiochemical purity was greater than 97%. The conjugate was stable during storage and under histidine and cysteine challenges and demonstrated receptor-specific binding. The biodistribution study demonstrated tumor-specific uptake levels (percentage injected activity per gram of tissue [%IA/g]) of 2.6 %IA/g for 99mTc-His6-(ZHER2:4)2 and 2.3 %IA/g for 125I-His6-(ZHER2:4)2 at 4 h after injection. Both conjugates provided clear imaging of SK-OV-3 xenografts at 6 h after injection. The tumor-to-nontumor ratios were much more favorable for the radioiodinated Affibody. CONCLUSION: The use of Tc(I)-carbonyl chemistry enabled us to prepare a stable, site-specifically labeled 99mTc-His6-(ZHER2:4)2 conjugate that was able to bind to HER2-expressing cells in vitro and in vivo. The indirectly radioiodinated conjugate provided better tumor-to-liver ratios. The labeling of Affibody molecules with 99mTc should be investigated further. 相似文献
46.
Cardiac efficiency and oxygen consumption measured with 11C-acetate PET after long-term cardiac resynchronization therapy. 总被引:2,自引:0,他引:2
Oliver Lindner Jens S?rensen Jürgen Vogt Eva Fricke Detlev Baller Dieter Horstkotte Wolfgang Burchert 《Journal of nuclear medicine》2006,47(3):378-383
Cardiac resynchronization therapy (CRT) is a treatment option in patients with severe heart failure and left bundle-branch block (LBBB). This study evaluated the effects of 4 and 13 mo of CRT on myocardial oxygen consumption (MVO2) and cardiac efficiency as compared with mild heart failure patients without LBBB. METHODS: Sixteen patients with severe heart failure and LBBB due to idiopathic cardiomyopathy were studied at baseline and after 4 and after 13 mo of therapy. Thirteen patients with mild heart failure without LBBB served as a comparison group. The clearance rate (k2) of 11C-acetate was measured with PET to assess MVO2. Stroke volume was derived from the dynamic PET data according to the Stewart-Hamilton principle and, furthermore, cardiac efficiency using the work metabolic index. RESULTS: After 4 mo of CRT, stroke volume index (SVI) increased by 50% (P = 0.012) and cardiac efficiency increased by 41% (P < 0.001). Global k2 remained unchanged but regional k2 demonstrated a more homogeneous distribution pattern. The parameters showed no significant changes during therapy. Under CRT, cardiac efficiency, SVI, and the distribution pattern of regional k2 did not differ from mild heart failure patients without LBBB. CONCLUSION: CRT improves cardiac efficiency for at least 13 mo, as demonstrated by a higher SVI, whereas MVO2 remains unchanged. Cardiac efficiency, SVI, and the MVO2 distribution pattern reach the level of patients with mild heart failure without LBBB. The unfavorable hemodynamic performance in heart failure with LBBB is effectively restored by long-term CRT to the level of an earlier disease state. 相似文献
47.
Claudia St?llberger Josef Finsterer Birke Schneider 《Journal of the American College of Cardiology》2006,47(7):1500; author reply 1500-1500; author reply 1501
48.
Pieter F Vos Oliver Zilch Aag Jennekens-Schinkel Miriam Salden Jasper Nuyen Menno P Kooistra M Alexander C van Huffelen Margriet M Sitskoorn 《Nephrology, dialysis, transplantation》2006,21(9):2529-2535
BACKGROUND: End-stage renal disease patients have a poor quality of life (QoL), suffer from impaired cognitive functioning, and their electroencephalogram (EEG) shows abnormalities. Conventional haemodialysis (CHD) only partially restores these disorders. Short daily haemodialysis (SDHD) has been reported to improve QoL, but effects on cognitive functioning and EEG have yet to be described. METHODS: Of the 13 patients (11 male, 2 female, age 45.5 +/- 8.1 years), 11 completed the Kidney Disease Quality of Life and Affect Balance Scale questionnaires, 10 underwent neuropsychological testing, and all 13 underwent EEG examination. For the neuropsychological assessments, nine patients (six male, three female, age 45.4 +/- 12.6) who remained on the CHD schedule, served as controls. The dialysis schedule of thrice-a-week for 4 h was changed in the experimental group to six times a week for 2 h (SDHD) over a period of 6 months and back to thrice a week for 4 h. RESULTS: When on SDHD, patients rated several dimensions of health-related QoL as being improved. After resuming CHD, one of these dimensions again decreased and several others worsened even lower than baseline. Cognitive functioning did not change when compared with control data. On the EEG, alpha peak frequency increased slightly when on SDHD but decreased significantly after resuming CHD. CONCLUSIONS: SDHD improves health-related QoL, but has no clear effects on cognitive functioning and EEG. Resumption of CHD after SDHD decreases aspects of QoL and EEG alpha peak frequency but has no effect on cognitive functioning. 相似文献
49.
Comparison of three different purification methods for the routine preparation of [11C] Metomidate. 总被引:1,自引:0,他引:1
Markus Mitterhauser Wolfgang Wadsak Oliver Langer Joern Schmaljohann Georg Zettinig Robert Dudczak Helmut Viernstein Kurt Kletter 《Applied radiation and isotopes》2003,59(2-3):125-128
PET with (R)-[O-methyl-11C] metomidate ([11C] MTO) is an attractive method for the characterisation of adrenal masses discriminating lesions of adrenal cortical origin from noncortical lesions. [11C] MTO was prepared by the reaction of [11C] methyliodide with the corresponding free acid. Three purification methods have been compared. The method of choice uses preparative HPLC with a ready-to-use weak acidic solvent. 相似文献
50.
Michael Brauckhoff Oliver Gimm Udo Bilkenroth Raoul Hinze Henning Dralle 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2002,387(5-6):201-203
BACKGROUND: In most examined populations the RET germline polymorphism S836S is found in about 3.6% of the normal population but in about 9% of patients suffering from sporadic C-cell hyperplasia or medullary thyroid carcinoma. The polymorphism S836S is thought to be involved in the development of sporadic medullary thyroid carcinoma. CASE PRESENTATION: We report a 48-year-old woman suffering from primary hyperparathyroidism (parathormone 121-166 pg/ml, normal <72), bilateral diffuse and nodular C-cell hyperplasia (calcitonin after pentagastrin administration 156 pg/ml, normal <4.6), and papillary thyroid carcinoma. Two commercial analyses of RET did not reveal any germline mutation within the known hot spots. However, sequencing revealed the presence of the RET polymorphism S836S. Following total thyroidectomy and removal of two hyperplastic parathyroid glands parathormone decreased to 51 pg/ml and calcitonin was no longer detected. CONCLUSIONS: The pathogenetic importance of the RET polymorphism S836S is still obscure. However, according to the published overrepresentation of the RET polymorphism S836S in patients suffering from apparent sporadic medullary thyroid carcinoma, it is conceivable that it also plays a role in multiglandular endocrine disease. 相似文献