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521.
Caesalpinia echinata, commonly known as Pau-brasil (Brazilwood), the famous tree that named Brazil is native to the Atlantic forest. Men extensively exploited it ever since discovery and colonial times due to its value as a source of red dye. As a consequence, Brazilwood is a threatened species with populations reduced to small forest fragments. Ten polymorphic microsatellite loci were developed from an enriched genomic library. Using fluorescently-labeled primers, a total of 83 alleles were found after analyzing a sample of 44 trees. These high genetic information content markers should allow detailed investigations of mating systems, gene flow, population structure and paternity in natural populations.  相似文献   
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In baboons trained to perform visuomotor pointing movements, unilateral electrolytic lesions are performed in the dentate nucleus. The consequences of these lesions on the following movement parameters are then studied:--temporal parameters: reaction time and movement time;--spatial parameters: pointing area and directional errors. From the observations taken 3 months after the dentate nucleus exclusion, a distinction can be made between parameters showing recovery phenomena (reaction time and pointing area) and components definitively affected (movement time and directional error).  相似文献   
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The sleep inducing effect of a 15 min treatment with either an active or an inactive Low Energy Emission Therapy (LEET) device emitting amplitude-modulated electromagnetic (EM) fields was investigated in a double-blind cross-over study performed on 52 healthy subjects. All subjects were exposed to both active and inactive LEET treatment sessions, with an interval of at least I week between the two sessions. LEET consists of 27.12 MHz amplitude-modulated (sine wave) EM fields emitted intrabuccally by means of an electrically conducting mouthpiece in direct contact with the oral mucosa. The estimated local peak SAR is less than 10 W/kg in the oral mucosa and 0.1 to 100 mW/kg in brain tissue. No appreciable sensation is experienced during treatment, and subjects are therefore unable to tell whether they are receiving an active or an inactive treatment. In this study the active treatment consisted of EM fields intermittently amplitude-modulated (sine wave) at 42.7 Hz for 3 s followed by a pause of 1 s during which no EM fields were emitted. During the inactive treatment no EM fields were emitted. Baseline EEGs were obtained and 15 min post-treatment EEGs were recorded and analyzed according to the Loomis classification. A significant decrease (paired t test) in sleep latency to stage B2 (?1.78 ± 5.57 min, P = 0.013), and an increase in the total duration of stage B2 (1.15 ± 2.47 min, P = 0.0008) were observed on active treatment as compared with inactive treatment. The deepest sleep stage achieved (B1 to D) following active treatment was also significantly higher than that following inactive treatment (P = 0.040). We conclude 27.12 MHz electromagnetic fields, intermittenly amplitude-modulated at 42.7 Hz, result in a significant sleep inducing effect in healthy subjects. © 1994 Wiley-Liss, Inc.  相似文献   
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