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81.
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Reinherz Helen Z.; Giaconia Rose M.; Hauf Amy M. Carmola; Wasserman Michelle S.; Silverman Amy B. 《Canadian Metallurgical Quarterly》1999,108(3):500
An ongoing longitudinal community study (N?=?375) examined childhood risks and later adult impairments associated with 1-year Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) diagnoses of major depression during the transition to adulthood. Risks from birth to age 9 were reported by mothers, participants, and teachers. Teacher-reported hostility at age 6 predicted later depression. At age 9, self-perceptions of anxiety/depression, unpopularity, familial rejection, and abuse were potent risks. For men, neonatal and childhood health problems predicted later depression. For women, risks included family constellation, parental death, and poor academic achievement at age 9. Men and women who were depressed at age 18, age 21, or both demonstrated extensive psychosocial impairments in early adulthood, including poor overall functioning, interpersonal and behavioral problems, low self-esteem, and suicidality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
F. Pellemoine W. MittigM. Avilov D. IppelJ. Lenz J. OlivaI. Silverman D. YouchisonT. Xu 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,655(1):3-9
One of the major challenges of the FRIB project (Facility for Rare Isotope Beams) at Michigan State University is the design and integration of the production target to produce rare isotope beams via fragmentation reaction. In the most extreme case, a 400 kW uranium beam of 200 MeV/u will be focused in a 1 mm diameter spot, leading to a power density of 60 MW/cm3 for a C target. Up to 200 kW may be dissipated in the target.A rotating solid carbon disk concept has been selected as the target design approach for all primary beams up to uranium to provide high-power operation. A high rotational speed is necessary to compensate for the high power density. A multi-slice approach allows the evacuation of the large amount of heat deposited by the increase of the radiating area. In the present design study, the multi-slice target device has a diameter of about 30 cm and rotates at about 5000 RPM (revolutions per minute). The first step of the R&D strategy consists in the development and test of a 20 kW single-slice target prototype. This single disk device is designed to accept the same fraction of power as each disk of the final multi-slice target. Critical information on thermal-mechanical properties can be obtained thus at a lower power level than the one of the full device. Different carbon materials were tested. An electron beam of ∼20 keV was used for the thermal tests. Simulations were performed using the ANSYS code for the thermo-mechanical behaviour of the target, the resulting deformation and the stress profiles of heated graphite disks. Results of the simulations were compared with experimental data. 相似文献
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Collagen-induced arthritis (CIA) is a T cell-dependent disease in which susceptibility is controlled by genes both within and outside the major histocompatibility complex (MHC). In the present study, we compared the humoral responses and kinetics of cytokine secretion patterns in the draining lymph nodes of arthritis-susceptible DA rats and arthritis-resistant F344 and DA MHC congenic PVG.1AV1 rats immunized with rat type II collagen (RCII) in incomplete Freund's adjuvant. The results demonstrate a marked humoral RCII response and a Th1 cytokine profile, with expression of interferon-gamma and interleukin (IL)-2 mRNA in DA rats; a limited humoral RCII response and a Th2 cytokine profile, with expression of IL-4 mRNA in arthritis-resistant F344 rats; and a marked humoral RCII response in arthritis-resistant PVG.1AV1 rats. However, in contrast to DA rats, PVG.1AV1 rats produce IgG1 autoantibodies which, together with strong expression of IL-4 mRNA, indicates the involvement of Th2 subsets. From these data, we conclude that non-MHC gene(s) determines the direction of the anti-RCII response towards a Th1 disease-promoting, or a Th2 disease-limiting response. 相似文献
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Pineda J.A. Silverman D.S. Vankov A. Hestenes J. 《IEEE transactions on neural systems and rehabilitation engineering》2003,11(2):181-184
The ability to control electroencephalographic rhythms and to map those changes to the actuation of mechanical devices provides the basis for an assistive brain-computer interface (BCI). In this study, we investigate the ability of subjects to manipulate the sensorimotor mu rhythm (8-12-Hz oscillations recorded over the motor cortex) in the context of a rich visual representation of the feedback signal. Four subjects were trained for approximately 10 h over the course of five weeks to produce similar or differential mu activity over the two hemispheres in order to control left or right movement in a three-dimensional video game. Analysis of the data showed a steep learning curve for producing differential mu activity during the first six training sessions and leveling off during the final four sessions. In contrast, similar mu activity was easily obtained and maintained throughout all the training sessions. The results suggest that an intentional BCI based on a binary signal is possible. During a realistic, interactive, and motivationally engaging task, subjects learned to control levels of mu activity faster when it involves similar activity in both hemispheres. This suggests that while individual control of each hemisphere is possible, it requires more learning time. 相似文献
89.
GJ Juvenal LB Pregliasco L Krawiec LV Bocanera D Silberschmidt MA Pisarev 《Canadian Metallurgical Quarterly》1997,7(5):795-800
The sympathetic nervous system plays a role in the regulation of thyroid function. In FRTL-5 rat thyroid cells, norepinephrine (NE) acutely depresses intracellular I- by increasing I- efflux. The present study was undertaken to determine the effect of NE on iodide transport after a longer time period. NE inhibited the ability of thyrotropin (TSH) to induce iodide uptake by FRTL-5 cells after 48 or 72 hours, but not after 24 hours. The effect of NE was more evident with increasing concentrations of TSH. NE did not modify the rate of I- efflux. Inhibition was associated with a decrease in the Vmax and no change in the Km for iodide influx. To determine if this was a generalized effect of NE on thyroid cell membrane, the uptake of alpha-aminoisobutyric acid (a nonmetabolizable aminoacid) and of 2-deoxyglucose was measured. NE did not inhibit TSH stimulation of the uptake of the two compounds. NE inhibited the action of dibutyryl cAMP (dbcAMP) on iodide uptake in a similar manner to TSH, but did not alter the cyclic adenosine monophosphate (cAMP) levels increased by TSH. The effects of different adrenoreceptor agonists and antagonists demonstrated that norepinephrine acts through an alpha1-adrenergic receptor. 相似文献
90.
LA Smith DE Barker CW Chase LB Somberg WB Brock RP Burns 《Canadian Metallurgical Quarterly》1997,63(12):1102-7; discussion 1107-8
The purpose of this review is to present a 4-year experience with the vacuum pack technique of temporary abdominal closure. From April 1992 to December 1996, 171 vacuum packs were performed on 93 patients. Eighty-seven vacuum packs were performed on 38 general surgical patients, and 84 vacuum packs were performed on 55 trauma patients. Overall hospital mortality was 32 per cent. Methods of achieving permanent wound closure varied in 73 patients. Four patients (4.3%) developed enterocutaneous fistulae; four patients developed intra-abdominal abscesses (4.3%). There were no eviscerations. Management of the complicated intra-abdominal process is discussed: 1) the decision to manage the abdomen in an open fashion; 2) which method of temporary closure to use; 3) subsequent explorations; 4) when the abdomen should be closed; 5) which type of closure to use; and 6) when the abdominal wall should be revised (herniorrhaphy). The vacuum pack is the method of choice for open abdomen management and temporary abdominal closure at our institution. With careful subsequent management, good patient outcome can be achieved. 相似文献