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排序方式: 共有806条查询结果,搜索用时 15 毫秒
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Ectopic tooth in the roof of the maxillary sinus 总被引:1,自引:0,他引:1
Eruption of a tooth into a nonoral environs is rare. Ectopic eruption of the tooth into the nasal cavity and chin has been reported before. This is a report of an ectopic third molar tooth in the roof of the maxillary sinus, which has not, to our knowledge, been reported before. 相似文献
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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
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Vasanthan Ravichandran Rajani Kant Rai Venkitasamay Kesavan 《Journal of biomaterials science. Polymer edition》2017,28(18):2131-2142
A new approach for the design and synthesis of cyclic N-halamine polymers having anti-bacterial activity based on a vinyl derivative of tyrosine-derived hydantoin is reported. The synthesis of N-halamine polymers generally involves the chemical modification of 5,5′-disubstituted hydantoin to introduce polymerizable vinyl moieties thereby restricting the halogen capture only on the amide nitrogen. Here we show the possibility of synthesizing vinyl monomers of N-halamine from α-amino acids wherein both the amide and imide nitrogens are available for halogen capture. Thus, a hydantoin monomer was synthesized from L-tyrosine and copolymerized with methyl methacrylate and 2-(hydroxyethyl)methacrylate, to obtain random co-polymers. The monomer and its co-polymers were characterized using NMR, IR, HRMS, GPC, DSC, EDAX and TGA analysis. Films of the co-polymers cast from 10% acetone solutions were exposed to sodium hypochlorite solution to activate the hydantoin moieties. The oxidative chlorine content of the films ranged from 0.6 to 0.9%. The activated films were exposed to both Gram positive (S. aureus) and Gram negative (E. coli) bacteria using standard protocols. Polymers having chlorine content as little as 0.6% exhibited 6 log reduction in the bacterial growth within 30 min of exposure. The method allows the halogenation of both amide and imide nitrogens and could be applied to the preparation of a number of vinyl hydantoins from many amino acids. 相似文献
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Geetha Ramachandran A. K. Hemanth Kumar P. K. Bhavani T. Kannan S. Ramesh Kumar N. Poorana Gangadevi V. V. Banurekha L. Sekar N. Ravichandran G. Mathevan G. N. Sanjeeva Rajeshwar Dayal Soumya Swaminathan 《Antimicrobial agents and chemotherapy》2015,59(2):1162-1167
The objective of this report was to study the pharmacokinetics of rifampin (RMP), isoniazid (INH), and pyrazinamide (PZA) in HIV-infected children with tuberculosis (TB) treated with a thrice-weekly anti-TB regimen in the government program in India. Seventy-seven HIV-infected children with TB aged 1 to 15 years from six hospitals in India were recruited. During the intensive phase of TB treatment with directly observed administration of the drugs, a complete pharmacokinetic study was performed. Drug concentrations were measured by high-performance liquid chromatography. A multivariable regression analysis was done to explore the factors impacting drug levels and treatment outcomes. The proportions of children with subnormal peak concentrations (Cmax) of RMP, INH, and PZA were 97%, 28%, and 33%, respectively. Children less than 5 years old had a lower median Cmax and lower exposure (area under the time-concentration curve from 0 to 8 h [AUC0–8]) of INH (Cmax, 2.5 versus 5.1 μg/ml, respectively [P = 0.016]; AUC0–8, 11.1 versus 22.0 μg/ml · h, respectively [P = 0.047[) and PZA (Cmax, 34.1 versus 42.3 μg/ml, respectively [P = 0.055]; AUC0–8, 177.9 versus 221.7 μg/ml · h, respectively [P = 0.05]) than those more than 5 years old. In children with unfavorable versus favorable outcomes, the median Cmax of RMP (1.0 versus 2.8 μg/ml, respectively; P = 0.002) and PZA (31.9 versus 44.4 μg/ml, respectively; P = 0.045) were significantly lower. Among all factors studied, the PZA Cmax influenced TB treatment outcome (P = 0.011; adjusted odds ratio, 1.094; 95% confidence interval, 1.021 to 1.173). A high proportion of children with HIV and TB had a subnormal RMP Cmax. The PZA Cmax significantly influenced treatment outcome. These findings have important clinical implications and emphasize that drug doses in HIV-infected children with TB have to be optimized. 相似文献
10.
N. Palaniappan I. S. Cole A. E. Kuznetsov Balasubramanian K. K. R. Justin Thomas 《RSC advances》2019,9(56):32441
Magnesium alloys are promising materials for the biomedical and automobile industries. The Mg alloy''s light-weight property leads to numerous industrial applications. However, the magnesium alloy oxide layers are not stable in salt environments. Organic inhibitors and epoxy coatings fail as long term barriers in such media. Recently, carbon based functionalized materials, graphene oxides, were shown to be promising materials for improving corrosion resistance in acid and salt environments. Our research considered graphene oxide covalently functionalized with the amino acid leucine to form anticorrosion coating materials. The functionalized materials were characterized by XRD, Raman, FESEM, HRTEM, FTIR, and AFM methods. The corrosion inhibition efficiency was monitored by electrochemical methods. The novelty of the functionalized graphene oxide materials is that they are water impermeable, and thus could enhance the anticorrosion resistance in salt environments.Leucine functionalized graphene oxide chemisorbed on a 111 surface AZ13 magnesium alloy via edge functional groups. 相似文献