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排序方式: 共有6122条查询结果,搜索用时 15 毫秒
31.
Siamak Mohammadi Emre Belli Ivo Martinovic Lucile Houyel André Capderou Jérome Petit Claude Planché Alain Serraf 《European journal of cardio-thoracic surgery》2005,28(2):217-222
OBJECTIVE: To identify the surgical approaches and risk factors which influence longevity of right ventricle to pulmonary artery (RV-PA) conduits following first reoperation for obstruction. METHODS: Between January 1993 and August 2003, 114 patients underwent 141 reoperations for RV-PA conduit obstruction. Diagnoses included 'Truncus Arteriosus' (n=52), 'Pulmonary atresia/Tetralogy of fallot' (n=39), 'Double outlet right ventricle' (n=10), 'Transposition of great arteries, VSD, and pulmonary atresia' (n=9), and the 'Ross operation' (n=4). All patients had undergone a previous biventricular repair. The first reoperation for conduit obstruction was performed in 112 hospital survivors by: total conduit replacement (Group A, n=73) with valved (homograft=10 and xenograft=54) or non-valved (n=9) conduit, and patch enlargement of the obstructed RV outflow tract with preservation of the posterior and sides of the conduit wall after removing of the fibrocalcific peel and degenerated valve (Group B, n=39). Mean age at first reoperation was 8.8+/-6.7 and 7.5+/-5.3 years in patients of groups A and B, respectively. Seven patients in Group A and 18 in Group B required a second reoperation and two patients in Group B a third reoperation. RESULTS: There were two hospital deaths and no late deaths. Mean follow-up was 5.8+/-3.2 years. Risk factors for second reoperation by univariate analysis were: homograft conduit use (P=0.004), Group B surgical approach (P=0.0001), higher RV-PA systolic pressure gradient at discharge (P=0.02), and age <5-years-old (P=0.01). Multivariate analysis showed that inclusion in Group B and younger age (<5-years-old) at repair were independent risk factors for second reoperation. Group B surgical approaches had higher RV-PA systolic pressure gradient at discharge (P=0.02) and required more PA bifurcation repair at the time of second reoperation (P=0.05). Freedom from second reoperation for conduit obstruction was significantly higher in Group A patients at 5 and 8 years (P<0.04) and those with xenografts rather than homograft (P=0.04). CONCLUSIONS: Our results support the optimal surgical approach for RV-PA conduit obstruction is total replacement with a xenograft. RV outflow reconstruction by other techniques without complete dissection of PA bifurcation does not completely relieve the stenosis and could cause early restenosis. Higher systolic gradients at discharge and younger age at first reoperation are predictors of earlier reoperation. 相似文献
32.
Ozkan Cem Dilek Emre Tezulas 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(2):e22-e25
The narrowing of an extraction site often becomes problematic when attempting to restore the space with a conventional wide-diameter implant. A woman is presented who was treated with a square head, mini-dental implant-supported fixed denture for a maxillary with a narrowed edentulous area, with a mesiodistal width of 5 mm. The implant, with a diameter of 2.4 mm, was inserted without reflecting the mucoperiosteal flap and was loaded immediately. During 12 months of follow-up, there has been no bone resorption and no inflammation observed around the implant. In conclusion, in terms of both clinical and aesthetic criteria, small diameter, mini-dental implants can be successfully used as an alternative to treatment with fixed partial dentures. 相似文献
33.
Dharmarajan Sriram Narasimharaghavan Srichakravarthy Tanushree R Bal Perumal Yogeeswari 《Biomedicine & Pharmacotherapy》2005,59(8):456-459
A series of nevirapine derivatives has been synthesized in an effort to enhance the spectrum of chemotherapeutic properties for the effective treatment of AIDS and AIDS-related opportunistic infections. The nevirapine derivative bearing isoniazid moiety (3a) was found to be the most potent compound with EC50 of<0.0636 microM, CC50 of>1000 microM and selectivity index of>15,723 which also exhibited 90% inhibition against Mycobacterium tuberculosis at 6.25 microg/ml. Compound 3c showed 100% inhibition against M. tuberculosis and also exhibited potent antibacterial activity against 24 pathogenic bacteria with MIC less than 1 microg/ml. 相似文献
34.
M Emre Celebi Hassan A Kingravi Bakhtiyar Uddin Hitoshi Iyatomi Y Alp Aslandogan William V Stoecker Randy H Moss 《Computerized medical imaging and graphics》2007,31(6):362-373
In this paper a methodological approach to the classification of pigmented skin lesions in dermoscopy images is presented. First, automatic border detection is performed to separate the lesion from the background skin. Shape features are then extracted from this border. For the extraction of color and texture related features, the image is divided into various clinically significant regions using the Euclidean distance transform. This feature data is fed into an optimization framework, which ranks the features using various feature selection algorithms and determines the optimal feature subset size according to the area under the ROC curve measure obtained from support vector machine classification. The issue of class imbalance is addressed using various sampling strategies, and the classifier generalization error is estimated using Monte Carlo cross validation. Experiments on a set of 564 images yielded a specificity of 92.34% and a sensitivity of 93.33%. 相似文献
35.
Gresham T Richter Jacob E Smith Horace J Spencer Chun Y Fan Emre Vural 《Otolaryngology--head and neck surgery》2007,137(2):239-242
OBJECTIVES: Histological comparison of human-based (AlloDerm) and porcine-based (ENDURAGen) dermal matrices regarding tissue incorporation and neovascularization as potential soft tissue augmentation materials. STUDY DESIGN: In vivo, rat model. METHODS: Subcutaneous implantation of 1-mm thick, 1 cm x 1 cm pieces of AlloDerm, ENDURAGen, and meshed ENDURAGen was performed in 24 Sprague Dawley rats. Implant materials were harvested at 4 (n = 12) and 8 weeks (n = 12). Histological quantification of soft tissue ingrowth and microvascular density was performed following hematoxylin-eosin staining and CD34 immunohistochemistry, respectively. RESULTS: AlloDerm showed significantly greater soft tissue ingrowth and microvascular density compared with both ENDURAGen and meshed ENDURAGen at 4 and 8 weeks (P < 0.001). CONCLUSIONS: Although these results may differ in human host tissues, AlloDerm seems to be a more suitable dermal matrix implant than ENDURAGen for cases in which tissue incorporation and neovascularization are sought for the optimal outcome based on this animal model. 相似文献
36.
M. S. Bal K. Kapoor T. Raj 《Indian journal of otolaryngology and head and neck surgery》1993,45(3):156-157
A 65 year old Punjabi male presented with an exophytic lesion, 3 Cm. in diameter, which was pedunculated, on the attached
gingiva. It was situated on the right side, near the motars. On histological examination, it was diagnosed as plasma cell
granuloma. 相似文献
37.
We examined the effect of hydrocortisone succinate on the growth of three isolates of Chlamydia pneumoniae in vitro. There was a significant increase in the number of inclusions seen in two of the C. pneumoniae strains in the presence of hydrocortisone. There was no significant increase in the number of inclusions with various concentrations of hydrocortisone over time. The addition of hydrocortisone did not affect the in vitro activities of azithromycin, erythromycin, and doxycycline against C. pneumoniae. 相似文献
38.
The purpose of this paper is to carry out an analysis of the term leukoplakia since its introduction in 1877 and to expose the most accepted concepts and present classification within specialists. For this purpose attention will be paid to definitions established in the international seminary developed in Malm? City, Sweden, in June 1983. A group of observations on present status of research and diagnostic methods and its limitations to pre-establish when a lesion of this type is going to evolve toward malignancy, is included. An important part of this paper is devoted to the linguistic analysis of leukoplakia and leukoplasia expressions. An extensive argumentation demonstrating the systematic impropriety in the Spanish Language of translating the English term "leukoplakia as leukoplasia, is presented. There is in Spanish the accurate translation, given by the expression leukoplakia, which is not only the adequate one for the exactness of its translation but also the one more conceptually adjusted to contemporary definition universally accepted, that is to say, a white plaque. Finally, a comment on importance of incorporates to our language the exact translation of scientific words, not only to fit it to present science, but also to a better fulfillment of its function in allowing the communication within Latin American researches themselves and with the world scientific community, is exposed. 相似文献
39.
40.
Improved DOP-PCR-based representational whole-genome amplification using quantitative real-time PCR.
Liliána Z Fehér Margit Balázs János Z Kelemen Agnes Zvara István Németh Zoltán Varga-Orvos László G Puskás 《Diagnostic molecular pathology》2006,15(1):43-48
In many cases, only a minute amount of partially degraded genomic DNA can be extracted from archived clinical samples. Diverse whole-genome amplification methods are applied to provide sufficient amount of DNA for comparative genome hybridization, single-nucleotide polymorphism, and microsatellite analyses. In these applications, the reliability of the amplification techniques is particularly important. In PCR-based approaches, the plateau effect can seriously alter the original relative copy number of certain chromosomal regions. To eliminate this distorting effect, we improved the standard degenerate oligonucleotide-primed PCR (DOP-PCR) technique by following the amplification status with quantitative real-time PCR (QRT-PCR). With real-time detection of the products, we could eliminate DNA overamplification. Probes were prepared from 10 different tumor samples: primary and metastatic melanoma tissues, epidermoid and bronchioloalveolar lung carcinomas, 2 renal cell carcinomas, 2 colorectal carcinomas, and a Conn and Cushing adenoma. Probes were generated by using nonamplified and amplified genomic DNA with DOP-PCR and DOP-PCR combined with QRT-PCR. To demonstrate the reliability of the QRT-PCR based amplification protocol, altogether 152 relative copy number changes of 44 regions were determined. There was 85.6% concordance in copy number alterations between the QRT-PCR protocol and the nonamplified samples, whereas this value was only 63.8% for the traditional DOP-PCR. Our results demonstrate that our protocol preserves the original copy number of different chromosomal regions in amplified genomic DNA than standard DOP-PCR techniques more accurately. 相似文献