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Rhesus monkeys with electrodes chronically implanted in reward sites in central tegmentum were given telemetered brain stimulation while they were free ranging alone or with cagemates. Stimulation seemed to induce a relaxed positive affect as measured by increased huddling, increased lipsmacking, reduced muscle tone, increased solicitation of grooming and increased grooming of other monkeys. Stimulation did not increase dominant/submissive interactions and seemed to have no effect on aggression or fear. These results are very different from those obtained from an anterolateral hypothalamic self-stimulation site and indicate that fibers which provide input from this area to anterolateral hypothalamus are not solely responsible for effects obtained in the anterolateral hypothalamic area.  相似文献   
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A simple, rapid mixed agglutination test using sheep erythrocytes (SRBC) sensitized with rabbit hemolysin and intact viable staphylococci is described for the detection of bound staphylococcal protein A. Soluble protein A was heat extracted from 50 clinical isolates as well as the Cowan I and Wood 46 strains of Staphylococcus aureus and titered by a hemagglutination test using sensitized SRBC and dilutions of soluble protein A. Protein A could be detected in all of these supernatants including that of S. aureus Wood 46, a strain generally considered to be protein A negative. These organisms were later retested by the mixed agglutination test and even those staphylococcal isolates expressing very low heat-extractable soluble protein A concentrations (1:2 titers) were positive, confirming the sensitivity of the test. In a screen of clinical isolates, only 4 of 235 (1.8%) coagulase-positive isolates were negative in the mixed agglutination test. Of 25 coagulase-negative isolates, none yielded a positive reaction.  相似文献   
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Electronic structure and magnetic properties of Fe3Se4 are calculated using the density functional approach. Due to the metallic properties, magnetic moments of the iron atoms in two nonequivalent positions in the unit cell are different from ionic values for Fe3+ and Fe2+ and are equal to M1=2.071μB and M2=2.042μB, making the system ferrimagnetic. The total magnetic moment for the unit cell is 2.135μB. Under isotropic compression, the total magnetic moment decreases non-monotonically and correlates with the non-monotonic dependence of the density of states at the Fermi level N(EF). For 7% compression, the magnetic order changes from the ferrimagnetic to the ferromagnetic. At 14% compression, the magnetic order disappears and the total magnetic moment becomes zero, leaving the system in a paramagnetic state. This compression corresponds to the pressure of 114 GPa. The magnetic ordering changes faster upon application of an isotropic external pressure due to the sizeable anisotropy of the chemical bondings in Fe3Se4. The ferrimagnetic and paramagnetic states occur under pressures of 5.0 and 8.0 GPa, respectively. The system remains in the metallic state for all values of compression.  相似文献   
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Spontaneous coronary artery dissection is a rare but increasingly recognized cause of acute myocardial ischemia in young adults, especially in women. We report a case of spontaneous coronary dissection in a young healthy man who was also a carrier of the factor V Leiden gene mutation.  相似文献   
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The principle of stretching wound margins for primary wound closure is commonly practiced and used for various skin defects, leading at times to excessive tension and complications during wound closure. Different surgical techniques, skin stretching devices and tissue expanders have been utilized to address this issue. Previously designed skin stretching devices resulted in considerable morbidity. They were invasive by nature and associated with relatively high localized tissue pressure, frequently leading to necrosis, damage and tearing of skin at the wound margins. To assess the clinical effectiveness and performance and, to determine the safety of TopClosure? for gradual, controlled, temporary, noninvasive and invasive applications for skin stretching and secure wound closing, the TopClosure? device was applied to 20 patients for preoperative skin lesion removal and to secure closure of a variety of wound sizes. TopClosure? was reinforced with adhesives, staples and/or surgical sutures, depending on the circumstances of the wound and the surgeon's judgment. TopClosure? was used prior to, during and/or after surgery to reduce tension across wound edges. No significant complications or adverse events were associated with its use. TopClosure? was effectively used for preoperative skin expansion in preparation for dermal resection (e.g., congenital nevi). It aided closure of large wounds involving significant loss of skin and soft tissue by mobilizing skin and subcutaneous tissue, thus avoiding the need for skin grafts or flaps. Following surgery, it was used to secure closure of wounds under tension, thus improving wound aesthetics. A sample case study will be presented. We designed TopClosure?, an innovative device, to modify the currently practiced concept of wound closure by applying minimal stress to the skin, away from damaged wound edges, with flexible force vectors and versatile methods of attachment to the skin, in a noninvasive or invasive manner.  相似文献   
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