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The authors have investigated the electrical activity of corpus cavernous, first according to Wagner and Gerstenberg’ method, then, since one year, according to Stief method, in the basal state and following intracavernosal injection of vasoactive agents, or following various stimulation tests. They have found again the electrical activity described by these authors, but have been confronted with the difficulty in quantifying the data. Specially single potential analysis seems to them little reliable and reproducible for an objective interpretation. At this stage of their experience, they test two simpler criteria interpretation: the richness of the electrical activity, and the reactivity of the recording to various stimulations. Their preminary results suggest a correlation between those criteria and the state of the autonomic nervous system of the penis.  相似文献   
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Complete sequences of the rRNA genes of Drosophila melanogaster   总被引:19,自引:0,他引:19  
In this, the first of three papers, we present the sequence of the ribosomal RNA (rRNA) genes of Drosophila melanogaster. The gene regions of D. melanogaster rDNA encode four individual rRNAs: 18S (1,995 nt), 5.8S (123 nt), 2S (30 nt), and 28S (3,945 nt). The ribosomal DNA (rDNA) repeat of D. melanogaster is AT rich (65.9% overall), with the spacers being particularly AT rich. Analysis of DNA simplicity reveals that, in contrast to the intergenic spacer (IGS) and the external transcribed spacer (ETS), most of the rRNA gene regions have been refractory to the action of slippage-like events, with the exception of the 28S rRNA gene expansion segments. It would seem that the 28S rRNA can accommodate the products of slippage-like events without loss of activity. In the following two papers we analyze the effects of sequence divergence on the evolution of (1) the 28S gene "expansion segments" and (2) the 28S and 18S rRNA secondary structures among eukaryotic species, respectively. Our detailed analyses reveal, in addition to unequal crossing-over, (1) the involvement of slippage and biased mutation in the evolution of the rDNA multigene family and (2) the molecular coevolution of both expansion segments and the nucleotides involved with compensatory changes required to maintain secondary structures of RNA.   相似文献   
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Physiological functions of mineral macronutrients   总被引:6,自引:0,他引:6  
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Percutaneous coronary intervention can be associated with distal embolization of thrombotic material causing myocardial necrosis and infarction. We discuss the role of intravascular imaging to guide the use of a distal protection device by describing the outcome of a young woman presenting with non-ST elevation myocardial infarction. Coronary angiography demonstrated an isolated minor stenosis in the proximal left anterior descending coronary artery with slight haziness beyond the lesion. Intravascular ultrasound confirmed an extensive thrombus overlying a bulky atherosclerotic plaque. A distal filter wire was therefore successfully used to reduce the risk of distal embolization. The use of intravascular ultrasound in patients presenting with acute coronary syndrome may reveal large thrombi that are difficult to image using conventional angiographic techniques. Intravascular ultrasound can therefore be used as a tool to select lesions requiring distal protection.  相似文献   
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Gemcitabine-squalene is a new prodrug that self-organizes in water forming nanoassemblies. It exhibits better anti-cancer properties in vitro and in vivo than gemcitabine. A liquid chromatography/tandem mass spectrometry assay of gemcitabine-squalene and gemcitabine was developed in human plasma in order to quantitate gemcitabine and its squalene conjugate. After protein precipitation with acetonitrile/methanol (90/10, v/v), the compounds were analyzed by reversed-phase high performance liquid chromatography and detected by tandem mass spectrometry using multiple reaction monitoring. The method was linear over the concentration range of 10-10,000 ng/ml of human plasma for both compounds with an accuracy lower than 10.4% and a precision below 14.8%. The method showed a lower limit of quantitation of 10 ng/ml of human plasma for dFdC and dFdC-SQ. A preliminary in vivo study in mice was shown as application of the method as no significant difference between human and mice plasma for the analysis of dFdC and dFdC-SQ was demonstrated.  相似文献   
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