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排序方式: 共有306条查询结果,搜索用时 265 毫秒
301.
Nahid Kondori Parisa Afshari Tehrani Louise Strömbeck Jan Faergemann 《Mycopathologia》2013,176(3-4):237-241
The laboratory diagnosis of dermatophytosis is usually based on direct microscopic examination and culturing of clinical specimens. A commercial polymerase chain reaction kit (Dermatophyte PCR) has had favorable results when used for detection of dermatophytes and identification of Trichophyton rubrum in nail specimens. This study investigated the efficacy of the Dermatophyte PCR kit for detecting dermatophytosis in 191 hair or skin specimens from patients with suspected dermatophytosis. PCR was positive for 37 % of samples, whereas 31 and 39 % of the specimens were positive by culturing and direct microscopy, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value for PCR analysis were 83, 84, 71, and 91 %, respectively. The sensitivity of the PCR test was higher in specimens obtained from skin (88 %) than in those obtained from hair (58 %), while the specificity remained almost the same (84 and 86 % for skin and hair, respectively). Our results show that the Dermatophyte PCR kit is a promising diagnostic tool for detection of dermatophytosis in skin samples, providing clinicians with a rapid diagnosis. 相似文献
302.
Liposomes, the artificial phospholipid vesicles, have the capacity of entrapping water soluble substances in their aqueous
compartments. Of the many possible potentials of liposomes their application in immunology is most significant. Recent studies
have shown an adjuvant and a carrier effect of liposomes to a number of antigens. Liposomes used in these studies are generally
multilamellar vesicles with the antigen encapsulated in the aqueous phase. Some antigens may also be associated with the lipid
lamellae covalently or noncovalently. The adjuvant property of liposomes is greatly affected by the surface charge of the
vesicle as well as the site of association of the antigen. The other factors which may have a role in immunopotentiation by
liposomes are the size and structure of the vesicles, the lipid composition, route of administration and their surface sugars.
In addition, liposomes may function as carriers to haptens and other antigens. In association with liposomes the nature of
the immune response may be modulated. For a further enhancement of the adjuvant activity of liposomes use has been made of
immunomodulators. 相似文献
303.
304.
Malihatosadat Gholamzadeh Nahid Hosseinzadeh Gharajeh Mohammad A. Hejazi 《Biotechnology progress》2019,35(2):e2773
Genetic investigation and in silico analysis of plantaricin EFI (plnEFI) locus was performed in three indigenous isolates of Lactobacillus plantarum EL3, L28 and BL1. Amplification with plnEFI specific primers and production of ~ 10 KDa size protein suggested the existence of class II bacteriocins. The analysis demonstrated that the studied fragment included structural bacteriocin, immunity, partial transporter and potential regulatory encoding regions. Based on the results, there was one DNA polymorphic site in plnE as well as plnF of the studied sequences. One nucleotide substitution in plnE of BL1 isolate lead to replacement of Glycin with Valine. These two are of non-polar type which did not affect instability index of plnE protein. The only nucleotide variation in plnF of EL3 isolate did not change the amino acid sequence since the modified nucleotide constituted alternative codon of the original amino acid. The highest DNA polymorphism occurred in the region with immunity function which in BL1 resulted in the conversion of start codon to amino acid codon. In the partial transporter sequence, one variable nucleotide site caused amino acid replacement in all the isolates which elevated stability of N-terminal domain in the transporter protein compared to nominated reference isolate L. plantarum C11. The region with possible regulatory function was identical in all three isolates. © 2018 American Institute of Chemical Engineers Biotechnol Progress, 35: e2773, 2019. 相似文献
305.
Anja Rautenberg Dmitry Filatov Bodil Svennblad Nahid Heidari Bengt Oxelman 《BMC evolutionary biology》2008,8(1):299
Background
Increasing evidence from DNA sequence data has revealed that phylogenies based on different genes may drastically differ from each other. This may be due to either inter- or intralineage processes, or to methodological or stochastic errors. Here we investigate a spectacular case where two parts of the same gene (SlX1/Y1) show conflicting phylogenies within Silene (Caryophyllaceae). SlX1 and SlY1 are sex-linked genes on the sex chromosomes of dioecious members of Silene sect. Elisanthe. 相似文献306.
Mohammad Amin Azimifar Zahra Salmasi Abbas Doosti Nahid Babaei Maryam Hashemi 《Biotechnology progress》2021,37(4):e3175
Interleukin 12 (IL-12) is considered as an important molecule for cancer immunotherapy with significant roles in hindering tumor activity, mostly mediated by tumor-associated macrophages and anti-angiogenic factors. Mesenchymal stem cells (MSCs) have been come out as promising carriers to increase the accumulation of drug/gene in tumor sites. As a vehicle, MSCs have various advantages, including tumor-specific propensity and migratory ability; however, they have limited transfection efficiency, compared to other cells. In this study, we introduced a novel delivery system based on poly-(amidoamine) (PAMAM) (G5) to deliver a plasmid encoding IL-12 to MSCs. Initially, 30% of the amine surface of PAMAM was substituted by 10-bromodecanoic acid. Then, the low molecular weight of protamine peptide was conjugated to PAMAM and PAMAM-alkyl with N-succinimidyl 3-(2-pyridyldithio) propionate as a linker. Physicochemical properties of this modified PAMAM were evaluated, including size and surface charge, toxicity, transfection efficiency to deliver reporter and IL-12 genes into MSCs and finally the migration potential of the engineered stem cells into cancer and normal cell lines (HepG2 and NIH/3 T3). The results showed that alkyl-peptide modified PAMAM with low toxicity had a higher potential to deliver green fluorescent protein and IL-12 genes to stem cells, than PMAMAM, PAMAM-alkyl and PAMAM-peptide. These engineered stem cells had a greater ability to migrate to cancer cells than normal cells. It can be concluded that engineered stem cells containing the IL-12 gene can be considered as an efficient cell carrier for cancer immunotherapy. Further clinical studies are needed to confirm these results. 相似文献