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排序方式: 共有418条查询结果,搜索用时 31 毫秒
1.
Detection of Pneumocystis carinii DNA in sputum and bronchoalveolar lavage samples by polymerase chain reaction. 总被引:4,自引:8,他引:4 下载免费PDF全文
A polymerase chain reaction (PCR)-based assay was developed for the detection of Pneumocystis carinii DNA in induced sputum and bronchoscopic alveolar lavage samples. The primer pair was selected from the published sequence of the thymidylate synthase gene of P. carinii derived from infected rats. The amplified DNA fragment of 403 bp was detected by agarose gel electrophoresis and by Southern and slot blot hybridization. No positive reaction was seen with DNA from different microorganisms typically found in the respiratory tract. P. carinii DNA was demonstrated in 30 of 42 sputum samples from immunosuppressed patients, whereas 21 of 42 sputum samples were positive by indirect immunofluorescence (IFL). Among the 42 patients, 14 were receiving prophylactic chemotherapy. In that group, PCR detected P. carinii in nine sputum samples, whereas IFL detected P. carinii in only four sputum samples. A positive PCR result was also seen in 5 of 43 IFL-negative bronchoscopic alveolar lavage samples from patients with respiratory symptoms. The PCR assay detected 10 copies of the target DNA, which corresponds to 10(-18) g of the specific P. carinii sequence. The results indicate that PCR amplification in combination with DNA hybridization is specific and is a more sensitive diagnostic method than IFL for the detection of P. carinii. 相似文献
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Gennady Bratslavsky Stephanie Gleicher Joseph M. Jacob Thomas H. Sanford Oleg Shapiro Dimitra Bourboulia Laurie M Gay Julie Andrea Elvin Jo-Anne Vergilio James Suh Shakti Ramkissoon Eric Allan Severson Jonathan Keith Killian Alexa Betzig Schrock Jon H. Chung Vincent A. Miller Mehdi Mollapour Jeffrey S. Ross 《Urologic oncology》2021,39(6):367.e1-367.e5
Introduction and ObjectiveUnlike clear cell renal cell carcinoma (CCRCC), collecting duct carcinoma (CDC) and renal medullary carcinoma (RMC) are rare tumors that progress rapidly and appear resistant to current systemic therapies. We queried comprehensive genomic profiling to uncover opportunities for targeted therapy and immunotherapy.Material and MethodsDNA was extracted from 40 microns of formalin-fixed, paraffin-embedded specimen from relapsed, mCDC (n = 46), mRMC (n = 24), and refractory and metastatic (m) mCCRCC (n = 626). Comprehensive genomic profiling was performed, and Tumor mutational burden (TMB) and microsatellite instability (MSI) were calculated. We analyzed all classes of genomic alterations.ResultsmCDC had 1.7 versus 2.7 genomic alterations/tumor in mCCRCC ( = 0.04). Mutations in VHL (P < 0.0001) and TSC1 (P = 0.04) were more frequent in mCCRCC. SMARCB1 (P < 0.0001), NF2 (P = 0.0007), RB1 (P = 0.02) and RET (P = 0.0003) alterations were more frequent in mCDC versus mCCRCC. No VHL alterations in mRMC and mCDC were identified. SMARCB1 genomic alterations were significantly more frequent in mRMC than mCDC (P = 0.0002), but were the most common alterations in both subtypes. Mutations to EGFR, RET, NF2, and TSC2 were more frequently identified in mCDC versus mRMC. The median TMB and MSI-High status was low with <1% of mCCRC, mCDC, and mRMC having ≥ 20 mut/Mb.ConclusionGenomic alteration patterns in mCDC and mRMC differ significantly from mCCRCC. Targeted therapies for mCDC and mRMC appear limited with rare opportunities to target alterations in receptor tyrosine kinase and MTOR pathways. Similarly, TMB and absence of MSI-High status in mCDC and mRMC suggest resistance to immunotherapies. 相似文献
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Enes Elvin Gul MD Rajiv A. Kabadi MD Santosh K. Padala MD Paula Sanchez Somonte MD Jordana Kron MD Richard K. Shepard MD Jayanthi N. Koneru MD Gautham Kalahasty MD Maria Terricabras MD Bernice Tsang MD Yaariv Khaykin MD Zaev Wulffhart MD Alfredo Pantano MD Kenneth A. Ellenbogen MD Atul Verma MD 《Journal of cardiovascular electrophysiology》2021,32(9):2515-2521
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Prediction of Secondary Structure of Proteins. A Comparison of the ?,Ψ Angles Previously Predicted for Cytochrome c with Recent X-Ray Crystallographic Findings 下载免费PDF全文
Elvin A. Kabat Tai Te Wu 《Proceedings of the National Academy of Sciences of the United States of America》1974,71(3):899-900
Newer data from the x-ray crystallographic studies of tuna heart ferrocytochrome c have increased the number of residues in alpha-helical segments. This provided an objective test of our method of predicting varphi,Psi values for cytochrome c using the sequences of 18 cytochromes c and twenty 20 x 20 tables for the varphi,Psi values of tripeptides in 10 other proteins whose three-dimensional structures were known from x-ray crystallographic studies. Of the 32 residues now considered from x-ray data to be in alpha-helices, 27 had been predicted to be in the alpha-helical domain. 相似文献
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Price ET Welder GJ Zineh I 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2012,26(2):95-99
Purpose
The PPAR-alpha agonists (fibrates) are commonly used in the treatment of dyslipidemia. It has been hypothesized that the cardio-protective effects of fibrates are partially due to immunomodulatory effects. However, there is a paucity of data regarding the effect of fibrates on neutrophilic chemokines such as epithelial neutrophil activating protein (ENA-78) and interleukin (IL)-8. We investigated the influence of fenofibrate on IL-1β-stimulated production of ENA-78 and IL-8 from human endothelial cells (HUVECs). 相似文献10.
The success rates of craniofacial osseointegrated implants are not uniform throughout the craniofacial area. A better understanding of their clinical behaviour is needed. This article investigates current perspectives on the application of endosseous implants in the restoration of craniofacial defects. An online search was completed for the time period from 1966 to 2007, along with a manual search, to locate relevant peer-reviewed articles and textbooks published in English. A review of published reports of craniofacial application of endosseous implants in irradiated and nonirradiated tissue sites showed a strong correlation between anatomic sites and clinical success. Maxillofacial prosthetic considerations are also reviewed. 相似文献