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The Lyme disease vaccine is based on the outer-surface lipoprotein (OspA) of the pathogen Borrelia burgdorferi, and 95% of vaccine recipients develop substantial titers of antibodies against OspA. Here, we identified seven individuals with very low antibody titers after vaccination (low responders). The macrophages of low responders produced less tumor necrosis factor-alpha and interleukin-6 after OspA stimulation and had lower cell-surface expression of Toll-like receptor (TLR) 1 as compared to normal cells, but normal expression of TLR2. TLRs activate innate responses to pathogens, and TLR2 recognizes lipoproteins and peptidoglycan (PGN). After OspA immunization, mice genetically deficient in either TLR2 (TLR2(-/-)) or TLR1 (TLR1(-/-)) produced low titers of antibodies against OspA. Notably, macrophages from TLR2(-/-) mice were unresponsive to OspA and PGN, whereas those from TLR1(-/-) mice responded normally to PGN but not to OspA. These data indicate that TLR1 and TLR2 are required for lipoprotein recognition and that defects in the TLR1/2 signaling pathway may account for human hyporesponsiveness to OspA vaccination.  相似文献   
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Erol OO 《Plastic and reconstructive surgery》2000,105(6):2229-41; discussion 2242-3
In nose surgery, carved or crushed cartilage used as a graft has some disadvantages, chiefly that it may be perceptible through the nasal skin after tissue resolution is complete. To overcome these problems and to obtain a smoother surface, the authors initiated the use of Surgicel-wrapped diced cartilage. This innovative technique has been used by the authors on 2365 patients over the past 10 years: in 165 patients with traumatic nasal deformity, in 350 patients with postrhinoplasty deformity, and in 1850 patients during primary rhinoplasty. The highlights of the surgical procedure include harvested cartilage (septal, alar, conchal, and sometimes costal) cut in pieces of 0.5 to 1 mm using a no. 11 blade. The fine-textured cartilage mass is then wrapped in one layer of Surgicel and moistened with an antibiotic (rifamycin). The graft is then molded into a cylindrical form and inserted under the dorsal nasal skin. In the lateral wall and tip of the nose, some overcorrection is performed depending on the type of deformity. When the mucosal stitching is complete, this graft can be externally molded, like plasticine, under the dorsal skin. In cases of mild-to-moderate nasal depression, septal and conchal cartilages are used in the same manner to augment the nasal dorsum with consistently effective and durable results. In cases with more severe defects of the nose, costal cartilage is necessary to correct both the length of the nose and the projection of the columella. In patients with recurrent deviation of the nasal bridge, this technique provided a simple solution to the problem. After overexcision of the dorsal part of deviated septal cartilage and insertion of Surgicel-wrapped diced cartilage, a straight nose was obtained in all patients with no recurrence (follow-up of 1 to 10 years). The technique also proved to be highly effective in primary rhinoplasties to camouflage bone irregularities after hump removal in patients with thin nasal skin and/or in cases when excessive hump removal was performed. As a complication, in six patients early postoperative swelling was more than usual. In 16 patients, overcorrection was persistent owing to fibrosis, and in 11 patients resorption was excessive beyond the expected amount. A histologic evaluation was possible in 16 patients, 3, 6, and 12 months postoperatively, by removing thin slices of excess cartilage from the dorsum of the nose during touch-up surgery. This graft showed a mosaic-type alignment of graft cartilage with fibrous tissue connection among the fragments. In conclusion, this type of graft is very easy to apply, because a plasticine-like material is obtained that can be molded with the fingers, giving a smooth surface with desirable form and long-lasting results in all cases. The favorable results obtained by this technique have led the authors to use Surgicel-wrapped diced cartilage routinely in all types of rhinoplasty.  相似文献   
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OBJECTIVE: To describe the diagnostic problems and present our findings in 2 uncommon tumors, malignant myoepithelioma and small cell undifferentiated carcinoma, by examining fine needle aspiration (FNA) biopsies of parotid gland masses. STUDY DESIGN: The study group consisted of 34 females and 41 males 12-80 years old, with an average of 44. Excluding inflammatory results, all adequate aspirates were confirmed histologically to determine the correlation. RESULTS: Sensitivity of FNA cytology was 91%, with specificity of 98%. We encountered some difficulties, and therefore misdiagnoses, in evaluating specific neoplasms, such as adenoid cystic carcinoma and Warthin's tumor, which have well-established cytologic diagnostic criteria. Two cases of uncommon neoplasms of salivary glands, small cell undifferentiated carcinoma and malignant myoepithelioma, were cytologically found to be malignant but not further classified. In addition, tuberculous parotitis, with its well-defined features, should to be referred since unnecessary surgery can be avoided by using FNA cytology. CONCLUSION: FNA is a sensitive and specific diagnostic tool for parotid gland masses. However, specific classification of neoplasms may sometimes be difficult. Pathologists should be aware of specific entities, such as malignant myoepithelioma, when evaluating high grade neoplasms.  相似文献   
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Bioprocess and Biosystems Engineering - Photofermentative production of hydrogen is a promising and sustainable process; however, it should be coupled to dark fermentation to become cost effective....  相似文献   
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We report a significantly-enhanced bioinformatics suite and database for proteomics research called Yale Protein Expression Database(YPED) that is used by investigators at more than 300 institutions worldwide. YPED meets the data management, archival, and analysis needs of a high-throughput mass spectrometry-based proteomics research ranging from a singlelaboratory, group of laboratories within and beyond an institution, to the entire proteomics community. The current version is a significant improvement over the first version in that it contains new modules for liquid chromatography–tandem mass spectrometry(LC–MS/MS) database search results, label and label-free quantitative proteomic analysis, and several scoring outputs for phosphopeptide site localization. In addition, we have added both peptide and protein comparative analysis tools to enable pairwise analysis of distinct peptides/proteins in each sample and of overlapping peptides/proteins between all samples in multiple datasets. We have also implemented a targeted proteomics module for automated multiple reaction monitoring(MRM)/selective reaction monitoring(SRM) assay development. We have linked YPED's database search results and both label-based and label-free fold-change analysis to the Skyline Panorama repository for online spectra visualization. In addition, we have built enhanced functionality to curate peptide identifications into an MS/MS peptide spectral library for all of our protein database search identification results.  相似文献   
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Biology Bulletin - The bioactive components of propolis differ according to geographical origins, plant resources and bee species. In our research, the chemical components, amino acid and vitamin...  相似文献   
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