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排序方式: 共有1658条查询结果,搜索用时 2 毫秒
31.
V Dogra S Verma G Singh A. H Wani R Chahota P Dhar L Verma M Sharma 《Majallah-i ta?qīqāt-i dāmpizishkī-i īrān》2015,16(4):350-356
Pasteurella multocida (P. multocida) is an important pathogen of various domestic animals. The outer membrane proteins (OMPs) play a major role in pathogenesis and immunogenicity of P. multocida. The aim of the study was to develop indirect enzyme linked immuno sorbant assay (ELISA) based on OMPs to ascertain the antibody titers in animals post-infection or to gauge the potency of vaccine. The OMPs were extracted and purified from P. multocida P:52 (vaccine strain) and P. multocida B:2 isolated from natural outbreak of Haemorrhagic septicaemia (HS) and analyzed on SDS PAGE and through western blot. The OMPs profile of the vaccine strain and the isolate from the natural outbreak of HS were found to be similar. Optimization of various components viz. coating antigens, anti-species conjugate, etc. were carried out against both anti-P. multocida hyper immune and pre immune serum. Validation of OMP based indirect ELISA assay to measure immune response against P. multocida in bovine revealed 91% diagnostic sensitivity (DSN) and about 100% diagnostic specificity (DSP) at 25% cut off. OMP based indirect ELISA was found to be more specific, but less sensitive as compared to WCL based assay.Key Words: Diagnostic sensitivity, Diagnostic specificity, Indirect ELISA, Outer membrane proteins, Pasteurella multocida 相似文献
32.
In vivo expression of the B7 costimulatory molecule by subsets of antigen-presenting cells and the malignant cells of Hodgkin's disease 总被引:10,自引:0,他引:10
Munro JM; Freedman AS; Aster JC; Gribben JG; Lee NC; Rhynhart KK; Banchereau J; Nadler LM 《Blood》1994,83(3):793-798
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites. 相似文献
33.
Karrer M. Alghazali Zeid A. Nima Rabab N. Hamzah Madhu S. Dhar 《Drug metabolism reviews》2015,47(4):431-454
Bone loss and failure of proper bone healing continues to be a significant medical condition in need of solutions that can be implemented successfully both in human and veterinary medicine. This is particularly true when large segmental defects are present, the bone has failed to return to normal form or function, or the healing process is extremely prolonged. Given the inherent complexity of bone tissue – its unique structural, mechanical, and compositional properties, as well as its ability to support various cells – it is difficult to find ideal candidate materials that could be used as the foundation for tissue regeneration from technological platforms. Recently, important developments have been made in the implementation of complex structures built both at the macro- and the nano-level that have been shown to positively impact bone formation and to have the ability to deliver active biological molecules (drugs, growth factors, proteins, cells) for controlled tissue regeneration and the prevention of infection. These materials are diverse, ranging from polymers to ceramics and various composites. This review presents developments in this area with a focus on the role of scaffold structure and chemistry on the biologic processes that influence bone physiology and regeneration. 相似文献
34.
Nucleotide sequence of the BK virus DNA segment encoding small t antigen. 总被引:12,自引:0,他引:12 下载免费PDF全文
R Dhar I Seif G Khoury 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(2):565-569
The nucleotide sequence from 0.64 to 0.53 map units in the BK virus genome coding for the small t protein has been determined. There is only one open reading frame that can code for a polypeptide of 172 amino acids, the putative small t protein. Beyond this segment, multiple termination codons are present in all three reading frames. There is considerable nucleotide and amino acid sequence homology between this region of BK virus and the analogous region of simian virus 40, especially in the proximal portion from 0.64 to 0.60 map units which is most likely common to the small t and large T BK virus proteins. A comparison of the conserved sequences within the early papovavirus genes both confirms the evolutionary relationship between these viruses and suggests the amino acid composition of the regions required for T antigen functions. 相似文献
35.
Jeremy YC Teoh Steffi KK Yuen James HL Tsu Charles KW Wong Brian SH Ho Ada TL Ng Wai-Kit Ma Kwan-Lun Ho Ming-Kwong Yiu 《Asian journal of andrology》2015,17(5):821-825
We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted. 相似文献
36.
Sean Marrache Shanta Dhar 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(40):16288-16293
Mitochondrial dysfunctions cause numerous human disorders. A platform technology based on biodegradable polymers for carrying bioactive molecules to the mitochondrial matrix could be of enormous potential benefit in treating mitochondrial diseases. Here we report a rationally designed mitochondria-targeted polymeric nanoparticle (NP) system and its optimization for efficient delivery of various mitochondria-acting therapeutics by blending a targeted poly(d,l-lactic-co-glycolic acid)-block (PLGA-b)-poly(ethylene glycol) (PEG)-triphenylphosphonium (TPP) polymer (PLGA-b-PEG-TPP) with either nontargeted PLGA-b-PEG-OH or PLGA-COOH. An optimized formulation was identified through in vitro screening of a library of charge- and size-varied NPs, and mitochondrial uptake was studied by qualitative and quantitative investigations of cytosolic and mitochondrial fractions of cells treated with blended NPs composed of PLGA-b-PEG-TPP and a triblock copolymer containing a fluorescent quantum dot, PLGA-b-PEG-QD. The versatility of this platform was demonstrated by studying various mitochondria-acting therapeutics for different applications, including the mitochondria-targeting chemotherapeutics lonidamine and α-tocopheryl succinate for cancer, the mitochondrial antioxidant curcumin for Alzheimer’s disease, and the mitochondrial uncoupler 2,4-dinitrophenol for obesity. These biomolecules were loaded into blended NPs with high loading efficiencies. Considering efficacy, the targeted PLGA-b-PEG-TPP NP provides a remarkable improvement in the drug therapeutic index for cancer, Alzheimer’s disease, and obesity compared with the nontargeted construct or the therapeutics in their free form. This work represents the potential of a single, programmable NP platform for the diagnosis and targeted delivery of therapeutics for mitochondrial dysfunction-related diseases. 相似文献
37.
Marchaim D Chopra T Bogan C Bheemreddy S Sengstock D Jagarlamudi R Malani A Lemanek L Moshos J Lephart PR Ku K Hasan A Lee J Khandker N Blunden C Geffert SF Moody M Hiro R Wang Y Ahmad F Mohammadi T Faruque O Patel D Pogue JM Hayakawa K Dhar S Kaye KS 《American journal of infection control》2012,40(8):760-765
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This project reports results from a questionnaire survey of sexual practices, contraception use and pregnancy plans in HIV-positive women in Leicester, UK, in order to establish the need for a dedicated sexual and reproductive health (SRH) clinic. The majority (96%) of women were aware of the benefits of antiretroviral therapy (ART) in pregnancy and 39% were planning a future pregnancy. Most (74%) used condoms consistently but their use decreased with the addition of another contraceptive method. Condoms were mostly obtained from non-National Health Service (NHS) settings. Long-acting reversible contraception (LARC) use was higher in this group of women than the general population and mainly provided by family planning services. A dedicated SRH clinic was thought to be useful by 79% of women. Data also identified some limitations of the existing service and need to provide holistic and integrated care. 相似文献