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排序方式: 共有3313条查询结果,搜索用时 46 毫秒
1.
E. Ozdemir Y. Kakehi M. Mishina O. Ogawa Y. Okada D. Ozdemir O. Yoshida 《British journal of cancer》1997,76(10):1348-1352
We report for the first time the frequency distributions of HLA-DRB1 and -DQB1 genes in 55 patients with testicular germ cell carcinoma (TGC) using the modified PCR-RFLP method and compare the results with those for 1216 healthy Japanese control subjects. The modified PCR-RFLP method produced accurate, reproducible cleavage patterns that are easily discriminated. HLA-DRB1*0410 was the susceptibility allele (RR = 3.26, P = 0.006) and DQB1*0602 appears to be a candidate protective allele (RR = 0.26, P = 0.02) for TGC in the Japanese. None of the HLA-DRB1 and -DQB1 alleles showed a specific tendency for histological type or clinical stage of the tumours. Previous studies based on serotyping methods failed to show these allelic associations. High-resolution genotyping is essential because the peptide-binding domain of MHC class II molecules is determined more precisely by their genotypes than by their serotypes. In addition, inherent technical difficulties and typing errors of up to 25% make serotyping inefficient. Our results suggest that high-resolution genotyping is a useful genetic marker to determine risk for TGC. 相似文献
2.
Comparison of the Exposure Obtained by Endoscope and Microscope in the Extended Trans-Sphenoidal Approach 总被引:1,自引:0,他引:1
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Objective: Trans-sphenoidal surgery is often combined with other approaches for the treatment of middle cranial base tumors. By combining a maxillotomy with trans-sphenoidal approach, significantly wider exposure to these regions is gained. However, endoscope-assisted techniques have also been used for sellar and parasellar and upper clival regions. Methods: An extended trans-sphenoidal approach was performed on 10 cadaver heads using the operating microscope and was repeated with a 0-degree endoscope. The mean horizontal and vertical distances were measured and pictured for each technique, and both distances were compared using a parametric paired Student's t-test. Results: The mean horizontal distances in the 10 specimens were 19.5 ± 1.8 mm by microscope and 27.5 ± 2.2 mm by endoscope, and the mean vertical distances were 25.8 ± 1.9 mm by the microscope and 34.5 ± 3.5 mm by the endoscope. Conclusion: The aim of this study was to quantify the amount of exposure obtained with an extended trans-sphenoidal approach and to compare both endoscopic and microscopic techniques. Using the endoscope in conjunction with the operating microscope may provide additional exposure and better access in skull base surgery. 相似文献
3.
The Arg753GLn polymorphism of the human toll-like receptor 2 gene in tuberculosis disease. 总被引:16,自引:0,他引:16
A C Ogus B Yoldas T Ozdemir A Uguz S Olcen I Keser M Coskun A Cilli O Yegin 《The European respiratory journal》2004,23(2):219-223
Toll-like receptor 2 (TLR2), a member of the Toll-like receptor family, plays an important role in recognition of, and subsequent immune response activation against, mycobacteria. The genetic polymorphism of TLR2 (arginine to glutamine substitution at residue 753 (Arg753Gln)) has been associated with a negative influence on TLR2 function, which may, in turn, determine the innate host response to mycobacteria. The aim of the present study was to investigate the Arg753Gln single nucleotide polymorphism of the TLR2 gene in tuberculosis (TB) patients compared to healthy controls. A retrospective case/control study was carried out. The Arg753Gln polymorphism of the TLR2 gene was studied in 151 TB patients compared to 116 ethnically and age-matched healthy control subjects. The TLR2 polymorphism (adenine (A) allele) was observed in 17.9 and 7.7% of TB patients and controls, respectively. When the ratios of the three genotypes were compared between the two groups, the AA genotype was found to be more significantly associated with TB. Allele frequencies for guanine (G) and A were found to be 0.95 and 0.05 in the control group and 0.86 and 0.14 in the TB patient group, respectively. The risk of developing TB disease was increased 6.04- and 1.60-fold for carriers of the AA and GA genotypes, respectively. In conclusion, the present data suggest that the arginine to glutamine substitution at residue 753 polymorphism of the Toll-like receptor 2 gene influences the risk of developing tuberculosis. 相似文献
4.
Some 2-methyl-3-triazole-substituted-4(3H)-quinazolinones 3a-f were prepared and tested for their H1- and H2-antihistaminic activities. In addition these compounds are central nervous system depressants and anticonvulsants. 3e shows highly significant decrease of locomotor activity. 相似文献
5.
Researchers usually employ orthogonal arrays or D-optimal designs with little or no attribute overlap in stated-choice surveys. The challenge is to balance statistical efficiency and respondent burden to minimize the overall error in the survey responses. This study examined whether simplifying the choice task, by using a design with more overlap, provides advantages over standard minimum-overlap methods. We administered two designs for eliciting HIV test preferences to split samples. Surveys were undertaken at four HIV testing locations in San Francisco, California. Personal characteristics had different effects on willingness to pay for the two treatments, and gains in statistical efficiency in the minimal-overlap version more than compensated for possible imprecision from increased measurement error. 相似文献
6.
Gülin Vural Mustafa Ünlü Tamer Atasever Izlem Özur Ayşegül Özdemir Nahide Gökçora 《European journal of nuclear medicine and molecular imaging》1997,24(3):312-315
Indium-111 octreotide and thallium-201 scintigraphic studies were compared in 21 patients (16 with palpable and five with non-palpable lesions) suspected of having breast malignancies on the basis of mammography. Early (15 min) and late (3 h)201Tl (111 MBq) and 4-h and 24-h111In-octreotide (111–148 MBq) static planar anterior images (matrix 256×256) were obtained on separate days. Images were evaluated both visually and quantitatively. Biopsy was performed following the imaging studies. Histopathology revealed 17 breast carcinomas (15 cases of invasive ductal carcinoma, one mucinous adenocarcinoma and one intraductal carcinoma) and four benign breast lesions (two fibroadenomas, one abscess and one case of fat necrosis). The means histopathologcial tumour size (mean largest diameter) was 3.38±1.9 cm.111In-octreotide detected 16 of the 17 breast cancers (94%) while201Tl detected 13 of them (76%). Both111In-octreotide and201Tl missed one nonpalpable carcinoma showing only an isolated cluster of microcalcifications on mammography. The smallest tumour size detected by both agents 1.5×1.5 cm. Of the four benign lesions, only the breast abscess revealed both201Tl and111In-octreotide uptake.111In-octreotide scan also showed tracer uptake in five of the six patients with histologically proven axillary metastases, while four of these six patients showed201Tl uptake. The tumour/background (T/B) ratios of late111In-octreotide and201Tl images were 1.71±0.38 and 1.46±0.30 respectively (P=0.039). In this preliminary study,111In-octreotide yielded more favourable results than201Tl in the detection of breast carcinomas. However, the diagnostic efficacy of111In-octreotide imaging needs to be investigated in larger patient series. 相似文献
7.
8.
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
9.
Hüseyin Katilmi? Sedat Oztürkcan Ismail Ozdemir I?il Adadan Aziz Tun? Ay?egül Akder Sinan Ba?o?lu 《Otolaryngology--head and neck surgery》2007,136(2):291-295
OBJECTIVE: This study evaluates the vocal cord and arytenoid mobility in relation to the tumoral involvement of the cricoarytenoid joint (CAJ), thyroarytenoid (TA) muscle, and posterior cricoarytenoid (PCA) muscle in whole-organ sections of total laryngectomy specimens. STUDY DESIGN AND SETTING: The study was prospectively carried out between 1998 and 2003 and involved 133 primary squamous cell carcinoma cases of larynx or pyriform sinus that were treated with total laryngectomy. Preoperative mobility of vocal cords and arytenoids were evaluated separately and correlated with histopathologic findings. RESULTS: In cases with fixed vocal cord CAJ, TA muscle, and PCA muscle were involved in 42.4%, 72.9%, and 27.1% of the cases, respectively, while in cases with fixed arytenoid these structures were affected in 40%, 66.3%, and 25.3% of the cases. Weight effect seemed to play a role in 60% and 50% of the cases of supraglottic and pyriform sinus carcinoma, respectively. CONCLUSION: Careful evaluation of the mobility of the cord arytenoid unit separately helps the surgeon to better understand the patterns of tumoral extension guiding for the appropriate surgery which should be undertaken. 相似文献
10.
Ozdemir O 《The Journal of allergy and clinical immunology》2005,116(5):1165-6; author reply 1166-7