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Several vaccine technologies were evaluated for their abilities to induce anti-human immunodeficiency virus Gag immune responses in rhesus macaques. While no vaccine alone was able to induce broad and strong immune responses, these were achieved by priming with Gag DNA and boosting with Gag protein adsorbed to polylactide coglycolide microparticles. This regimen elicited strong antibodies, helper T cells, and cytotoxic T lymphocytes and thus holds promise as an effective vaccination scheme.  相似文献   
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Molecular weights (molar masses), molecular weight distributions, dissociation constants and other interaction parameters are fundamental characteristics of proteins, nucleic acids, polysaccharides and glycoconjugates in solution. Sedimentation equilibrium analytical ultracentrifugation provides a powerful method with no supplementary immobilization, columns or membranes required. It is a particularly powerful tool when used in conjunction with its sister technique, namely sedimentation velocity. Here, we describe key approaches now available and their application to the characterization of antibodies, polysaccharides and glycoconjugates. We indicate how major complications, such as thermodynamic non-ideality, can now be routinely dealt with, thanks to a great extent to the extensive contribution of Professor Don Winzor over several decades of research.  相似文献   
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A survey of mean blood pressure levels in age-and-sex-matched samples of the population of the island of Tiree appears to support the local belief that blood pressure is higher on the island than on the mainland. This conclusion may be related to the observation of a greater mean width of the heart, measured radiologically, in the island population compared with the mainland population. The greater mean body weight observed in the island compared with the mainland may be a factor. Blood pressure in men between the ages of 40 and 59 years is higher in Tiree than in selected samples in England and America.  相似文献   
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During jumping or falling in humans and various other mammals, limb muscles are activated before landing, and the intensity and timing of this pre-landing activity are scaled to the expected impact. In this study, we test whether similarly tuned anticipatory muscle activity is present in hopping cane toads. Toads use their forelimbs for landing, and we analysed pre-landing electromyographic (EMG) timing and intensity in relation to hop distance for the m. coracoradialis and m. anconeus, which act antagonistically at the elbow, and are presumably important in stabilizing the forelimb during landing. In most cases, a significant, positive relationship between hop distance and pre-landing EMG intensity was found. Moreover, pre-landing activation timing of m. anconeus was tightly linked to when the forelimbs touched down at landing. Thus, like mammals, toads appear to gauge the timing and magnitude of their impending impact and activate elbow muscles accordingly. To our knowledge these data represent the first demonstration of tuned pre-landing muscle recruitment in anurans and raise questions about how important the visual, vestibular and/or proprioceptive systems are in mediating this response.  相似文献   
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