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61.
Osteomyelitis is an infectious disease located in the bone or bone marrow. Long-circulating and pH-sensitive liposomes containing a technetium-99m-labeled antibiotic, ceftizoxime, (SpHL-(99m)Tc-CF) were developed to identify osteomyelitis foci. Biodistribution studies and scintigraphic images of bone infection or non infection-bearing rats that had been treated with these liposomes were performed. A high accumulation in infectious foci and high values in the target-non target ratio could be observed. These results indicate the potential of SpHL-(99m)Tc-CF as a potential agent for the diagnosis of bone infections.  相似文献   
62.
Gongora, J., Cuddahee, R. E., do Nascimento, F. F., Palgrave, C. J., Lowden, S., Ho, S. Y. W., Simond, D., Damayanti, C. S., White, D. J., Tay, W. T., Randi, E., Klingel, H., Rodrigues‐Zarate, C. J., Allen, K., Moran, C. & Larson, G. (2011). Rethinking the evolution of extant sub‐Saharan African suids (Suidae, Artiodactyla). —Zoologica Scripta, 40, 327–335. Although African suids have been of scientific interest for over two centuries, their origin, evolution, phylogeography and phylogenetic relationships remain contentious. There has been a long‐running debate concerning the evolution of pigs and hogs (Suidae), particularly regarding the phylogenetic relationships among extant Eurasian and African species of the subfamily Suinae. To investigate these issues, we analysed the mitochondrial and nuclear DNA sequences of extant genera of Suidae from Eurasia and Africa. Molecular phylogenetic analyses revealed that all extant sub‐Saharan African genera form a monophyletic clade separate from Eurasian suid genera, contradicting previous attempts to resolve the Suidae phylogeny. Two major sub‐Saharan African clades were identified, with Hylochoerus and Phacochoerus grouping together as a sister clade to Potamochoerus. In addition, we find that the ancestors of extant African suids may have evolved separately from the ancestors of modern day Sus and Porcula in Eurasia before they colonised Africa. Our results provide a revision of the intergeneric relationships within the family Suidae.  相似文献   
63.
A lectin from the red marine alga Hypnea musciformis (HML) was purified by extraction with 20 mM PBS, precipitation with 70% saturated ammonium sulphate, ion-exchange DEAE-Cellulose chromatography and RP-HPLC. The 9.3 kDa polypeptide agglutinates erythrocytes from various sources and shows oligomerization tendencies under certain MALDI-TOF/MS conditions. Preliminary N-terminal sequencing and biological assays strongly suggest that the HML may belong to a new class of algae lectins.  相似文献   
64.
Random amplified polymorphic DNA analysis was applied to DNAs extracted from Trichuris trichiura eggs recovered from human fecal samples. Four out of 6 primers tested displayed 18 distinct and well defined polymorphic patterns, ranging from 650 to 3200 base pairs. These results, upon retrieval and DNA sequencing of some of these bands from agarose gels, might help in establishing. T. trichiura specific genetic markers, not available yet, and an important step to design primers to be used in molecular diagnosis approaches.  相似文献   
65.
Glycoconjugate Journal - The complex enzyme network responsible for glycan synthesis suffers significant changes during the first steps of tumor development, leading to the early formation of...  相似文献   
66.
Sporotrichosis is a chronic granulomatous mycosis caused by the dimorphic fungus Sporothrix schenckii, which is widely distributed in nature, and presents a saprophytic mycelial form on plant debris and soil. The immunological mechanisms involved in the prevention and control of sporotrichosis are not yet fully understood. In this study, mice were studied after infection with Sporothrix schenckii. In the first week after infection, fungal loading increased and thence decreased drastically 14 days after infection. Analysis by immunoblotting showed that the sera of all mice tested had antibodies reacting only with a 70 kDa antigen, with predominance of IgG1 and IgG3. Taken together, our results show that antigens from S. schenckii induced a specific humoral response in infected mice.  相似文献   
67.
The dichloromethane extract of Calea uniflora afforded a mixture of two novel chromanones, uniflorol-A (1) and uniflorol-B (2), and one known chromanone, 2,2-dimethyl-6-(1-hydroxyethyl)-chroman-4-one (3). The structures of these compounds were determined by spectroscopic methods. Biological activity of the compounds against Leishmania major promastigotes was evaluated. Mixture of the novel chromanones 1 and 2 showed significant growth inhibition of the parasite in the micrograms per milliliter range.  相似文献   
68.
Analogs of pralidoxime, which is a commercial antidote for intoxication from neurotoxic organophosphorus compounds, were designed, synthesized, characterized, and tested as potential inhibitors or reactivators of acetylcholinesterase (AChE) using the Ellman’s test, nuclear magnetic resonance, and molecular modeling. These analogs include 1-methylpyridine-2-carboxaldehyde hydrazone, 1-methylpyridine-2-carboxaldehyde guanylhydrazone, and six other guanylhydrazones obtained from different benzaldehydes. The results indicate that all compounds are weak AChE reactivators but relatively good AChE inhibitors. The most effective AChE inhibitor discovered was the guanylhydrazone derived from 2,4-dinitrobenzaldehyde and was compared with tacrine, displaying similar activity to this reference material. These results indicate that guanylhydrazones as well as future similar derivatives may function as drugs for the treatment of Alzheimer's disease.  相似文献   
69.
The currently used pertussis vaccines are highly efficacious; however, neonates are susceptible to whooping cough up to the sixth month. In agreement, DTP-immunized neonate mice were not protected against intracerebral challenge with Bordetella pertussis. Neonate mice immunized with either DTP or a recombinant-BCG strain expressing the genetically detoxified S1 subunit of pertussis toxin do not show a humoral immune response against PT. On the other hand, rBCG-Pertussis induces higher PT-specific IFN-gamma production and an increase in both IFN-gamma(+) and TNF-alpha(+)-CD4(+)-T cells than the whole cell pertussis vaccine and confers protection against a lethal intracerebral challenge with B. pertussis.  相似文献   
70.
Diterpene esters of aristolochic acids from Aristolochia pubescens   总被引:3,自引:0,他引:3  
From the acetone and ethanol extracts of the tubercula of Aristolochia pubescens, two diterpene esters of aristolochic acids were isolated, together with 23 known compounds. The structures of the compounds were determined on the basis of spectroscopic analysis.  相似文献   
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