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排序方式: 共有1725条查询结果,搜索用时 29 毫秒
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N. J. Carty C. Carter C. Rubin D. Ravichandran G. T. Royle I. Taylor 《Annals of the Royal College of Surgeons of England》1995,77(2):127-130
Fibroadenoma is a common cause of discrete breast lumps in young women. There is agreement that fibroadenomas can be diagnosed preoperatively with a high degree of confidence and that some of the lesions thus diagnosed will resolve, possibly obviating the need for excision. There is, however, wide disagreement over the proportion of fibroadenomas that resolve spontaneously and therefore the benefit that accrues from an expectant policy. The aim of this study was to audit the management of fibroadenomas on one unit and clarify their natural history over a 5-year period. A cohort of 70 women with 87 fibroadenomas diagnosed using a triple assessment of clinical examination, cytology and imaging (sonomammography) have been followed for a minimum of 5 years. In all, 53 of the 'fibroadenomas' have been excised. In four cases the histology revealed benign disease other than fibroadenoma; there were no neoplasms. The sensitivity of cytology and sonomammography for the diagnosis of fibroadenoma were 84% and 98% respectively. Thirty-four fibroadenomas have not been excised. Of 25 fibroadenomas that have been reassessed after at least 5 years of follow-up, 13 (52%) have reduced in size, 4 (16%) are unchanged in size and 8 (32%) have grown. No patient has developed a carcinoma at the site of the presumed fibroadenoma. This study confirms that an expectant management policy of fibroadenomas has not resulted in misdiagnosis of carcinomas. Further, since a significant proportion of fibroadenomas remain static or reduce in size over a 5-year period many women can avoid excision. 相似文献
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Differential PsaA-, PspA-, PspC-, and PdB-specific immune responses in a mouse model of pneumococcal carriage 下载免费PDF全文
Palaniappan R Singh S Singh UP Sakthivel SK Ades EW Briles DE Hollingshead SK Paton JC Sampson JS Lillard JW 《Infection and immunity》2005,73(2):1006-1013
Larger numbers of pneumococci were detected in the nasal tract compared to the lung, cervical lymph nodes, and spleen 1, 2, 4, 7, 14, and 21 days after nasal challenge with Streptococcus pneumoniae strain EF3030. In this mouse model of pneumococcal carriage, peripheral S. pneumoniae pneumococcal surface adhesin A (PsaA)-specific humoral responses (immunoglobulin G2a [IgG2a] > IgG1 = IgG2b > IgG3) were significantly higher than pneumococcal surface protein A (PspA)-specific, genetic toxoid derivative of pneumolysin (PdB)-specific, or pneumococcal surface protein C (PspC)-specific serum antibody levels. However, PspA-specific mucosal IgA antibody levels were significantly higher than those against PsaA, PdB, and PspC. In general, both PsaA- and PspA-specific lung-, cervical lymph node-, nasal tract-, and spleen-derived CD4(+) T-cell cytokine (interleukin-4, interleukin-6, granulocyte-macrophage colony-stimulating factor, gamma interferon, and tumor necrosis factor alpha) and proliferative responses were higher than those for either PspC or PdB. Taken together, these findings suggest that PsaA- and PspA-specific mucosal responses as well as systemic humoral and T helper cell cytokine responses are predominantly yet differentially induced during pneumococcal carriage. 相似文献
4.
Donnadieu E Jouvin MH Rana S Moffatt MF Mockford EH Cookson WO Kinet JP 《Immunity》2003,18(5):665-674
Allergic reactions are triggered via crosslinking of the high-affinity receptor for immunoglobulin E, F(c)epsilonRI. In humans, F(c)epsilonRI is expressed as a tetramer (alphabetagamma(2)) and a trimer (alphagamma(2)). The beta subunit is an amplifier of F(c)epsilonRI surface expression and signaling. Here, we show that as a consequence of alternative splicing, the F(c)epsilonRIbeta gene encodes two proteins with opposing and competing functions. One isoform is the full-length classical beta, the other a novel truncated form, beta(T). In contrast to beta, beta(T) prevents F(c)epsilonRI surface expression by inhibiting alpha chain maturation. Moreover, beta(T) competes with beta to control F(c)epsilonRI surface expression in vitro. We propose that the relative abundance of the products of the beta gene may control the level of F(c)epsilonRI surface expression and thereby influence susceptibility to allergic diseases. 相似文献
5.
Zeynep H. Coban‐Akdemir Wu‐Lin Charng Mahshid Azamian Ingrid S. Paine Jaya Punetha Christopher M. Grochowski Tomasz Gambin Santiago O. Valdes Bryan Cannon Gladys Zapata Patricia P. Hernandez Shalini Jhangiani Harsha Doddapaneni Jianhong Hu Fatima Boricha Donna M. Muzny Eric Boerwinkle Yaping Yang Richard A. Gibbs Jennifer E. Posey Xander H. T. Wehrens John W. Belmont Jeffrey J. Kim Christina Y. Miyake James R. Lupski Seema R. Lalani 《American journal of medical genetics. Part A》2020,182(6):1387-1399
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Guy N.J. Betts Amanda Eustace Shalini Patiar Helen R. Valentine Joely Irlam Anassuya Ramachandran Ashirwad Merve Jarrod J. Homer Carla Möller-Levet Francesca M. Buffa Gillian Hall Crispin J. Miller Adrian L. Harris Catharine M.L. West 《European journal of cancer (Oxford, England : 1990)》2013,49(1):156-165
Background and purposeTumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours.Materials and methodsTumour samples (n = 201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV).ResultsThe assay was sensitive with linear reaction efficiencies across a 4log10 range of inputted cDNA (0.001–10 ng/μl). Intra- (CoV = 6.9%) and inter- (CoV = 2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO2. TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p < 0.01) and positive pimonidazole scores (p = 0.005).ConclusionsGene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material. 相似文献
8.
Shalini Narayanan Joyanta K. Modak Catherine S. Ryan Jose Garcia-Bustos John K. Davies Anna Roujeinikova 《Antimicrobial agents and chemotherapy》2014,58(5):2754-2762
Due to their lack of toxicity to mammalian cells and good serum stability, proline-rich antimicrobial peptides (PR-AMPs) have been proposed as promising candidates for the treatment of infections caused by antimicrobial-resistant bacterial pathogens. It has been hypothesized that these peptides act on multiple targets within bacterial cells, and therefore the likelihood of the emergence of resistance was considered to be low. Here, we show that spontaneous Escherichia coli mutants resistant to pyrrhocoricin arise at a frequency of approximately 6 × 10−7. Multiple independently derived mutants all contained a deletion in a nonessential gene that encodes the putative peptide uptake permease SbmA. Sensitivity could be restored to the mutants by complementation with an intact copy of the sbmA gene. These findings question the viability of the development of insect PR-AMPs as antimicrobials. 相似文献
9.
Anju Sinha Nomita Chandhiok Seema Sahay Sibnath Deb Shalini Bharat Abhilasha Gupta 《AIDS care》2015,27(9):1196-1198
A compelling case for promoting male circumcision (MC) as an intervention for reducing the risk of heterosexually acquired HIV infection was made by dissemination of the results of three studies in Africa. The WHO/UNAIDS recommendation for MC for countries like India, where the epidemic in concentrated in high-risk groups, advocates MC for specific population groups such as men at higher risk for HIV acquisition. A multicentre qualitative study was conducted in four geographically distinct districts (Belgaum, Kolkata, Meerut and Mumbai) in India during June 2009 to June 2011. Two categories of health care providers: Registered Healthcare Providers (RHCPs) and traditional circumcisers were interviewed by trained research staff who had received master's level education using interview guides with probes and open-ended questions. Respondents were selected using purposive sampling. A comparative analysis of the perspectives of the RHCP vs. traditional circumcisers is presented. Representatives of both categories of providers expressed the need for Indian data on MC. Providers feared that promoting circumcision might jeopardize/undermine the progress already made in the field of condom promotion. Reservation was expressed regarding its adoption by Hindus. Behavioural disinhibition was perceived as an important limitation. A contrast in the practice of circumcision was apparent between the traditional and the trained providers. MC should be mentioned as a part of comprehensive HIV prevention services in India that includes HIV counselling and testing, condom distribution and diagnosis and treatment of sexually transmitted infections. It should become an issue of informed personal choice rather than ethnic identity. 相似文献
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