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991.
Radnitz Cynthia L.; Hsu Louis; Tirch Dennis D.; Willard Jeffrey; Lillian Lynn B.; Walczak Stacey; Festa Joanne; Perez-Strumolo Lysandra; Broderick Charles P.; Binks Martin; Schlein Ilana; Bockian Neil; Green Leon; Cytryn Arthur 《Canadian Metallurgical Quarterly》1998,107(4):676
The authors assessed effects of paraplegic and quadriplegic spinal cord injuries (SCls) on posttraumatic stress disorder (PTSD) by comparing severity and prevalence of PTSD in these groups to a sample of controls who experienced traumatic injuries other than SCI. The authors found that veterans with quadriplegia reported significantly less severe current PTSD symptoms than controls who were not significantly different from veterans with paraplegia. These results suggest that sustaining a quadriplegic SCI decreases risk of current PTSD, whereas sustaining a paraplegic SCI is associated with greater risk of PTSD, although the risk is no greater than that incurred from experiencing the trauma itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
993.
Ion cooling and axialization produced by azimuthal quadrupolar excitation in the presence of ion-neutral collisions are applied to laser desorption Fourier transform ion cyclotron resonance mass spectrometry (LD/FT/ICR-MS). With this technique, the large kinetic and internal energies of ions generated by laser desorption processes can be cooled effectively by collisions of ions with neutral argon atoms (at > 5 x 10(-7) Torr). After sufficient cooling in the source compartment of a dual ion trap, the axialized ions may be transferred to the analyzer compartment for detection at much lower pressure (and thus much higher mass resolving power). Enhancements in both FT/ICR mass resolving power and sensitivity are observed; moreover, ion isolation with high selectivity at high pressure is also demonstrated. 相似文献
994.
995.
Postoperative fatigue (POF) appears to be less following laparoscopic surgery but this has not been proven previously. This study compared a group of patients who had undergone open cholecystectomy with a group undergoing laparoscopic cholecystectomy. Postoperative fatigue was found to be decreased in duration in the patients having laparoscopic surgery, returning to pre-operative fatigue levels by 14 days, compared to 28 days for open surgery. Postoperative pain in the first 24 h and the early metabolic response to surgery were similar for both groups. The authors conclude that laparoscopic surgery is associated with decreased POF and that this is unlikely to be accounted for by a decrease in the early metabolic response to surgery. 相似文献
996.
SJ Peter MJ Yaszemski LJ Suggs RG Payne R Langer WC Hayes MR Unroe LB Alemany PS Engel AG Mikos 《Canadian Metallurgical Quarterly》1997,8(11):893-904
Neointimal formation and arterial wall remodeling are pivotal causes of luminal narrowing in atherogenesis and restenosis. Arterial remodeling refers to a series of dynamic structural changes that arteries may undergo in response to various stimuli, including changes in blood flow and pressure, and acute injury. The biological mechanisms involved in arterial remodeling are poorly understood and are currently a main target for research. We have recently focused on the role of the arterial wall microcirculation (ie, vasa vasorum) in arterial remodeling after injury. In the past, a correlation between arterial wall neovascularization and the accumulation of arterial plaque has been documented; however, the dynamic role of these microvessels in arterial repair and luminal narrowing has not been examined. The type of arterial injury, the nature of the lesion that develops, and the arterial compartment in which angiogenesis occurs may determine the role of the vasa vasorum in arterial narrowing. In this review, we highlight the data that link arterial wall neovascularization with lesion formation and the process of arterial remodeling. 相似文献
997.
BT Veering PM Ter Riet AG Burm R Stienstra JW Van Kleef 《Canadian Metallurgical Quarterly》1996,77(3):343-346
In this randomized, observer-blind study, we have examined, in elderly patients, the effect of site of injection on analgesia levels after spinal injection of 0.5% hyperbaric bupivacaine solution. Thirty male patients, aged 68-87 yr, undergoing minor urological surgery during spinal anaesthesia received 3 ml of a 0.5% hyperbaric bupivacaine solution at either the L3-4 (n = 15) or L4-5 (n = 15) interspace. The solution was injected with the patient in the sitting position. The patient remained sitting for 2 min and was then placed in the supine horizontal position. Analgesia levels were assessed bilaterally using pin-prick. The highest analgesia levels did not differ between groups (medians were approximately T7). There were no significant differences in the time to maximum cephalad spread of analgesia, maximum degree of motor block or haemodynamic changes. We conclude that injection at the L4-5 interspace has no advantage compared with injection at the L3-4 interspace. 相似文献
998.
999.
AG Yakovlev SM Knoblach L Fan GB Fox R Goodnight AI Faden 《Canadian Metallurgical Quarterly》1997,17(19):7415-7424
We examined the temporal profile of apoptosis after fluid percussion-induced traumatic brain injury (TBI) in rats and investigated the potential pathophysiological role of caspase-3-like proteases in this process. DNA fragmentation was observed in samples from injured cortex and hippocampus, but not from contralateral tissue, beginning 4 hr after TBI and continuing for at least 3 d. Double labeling of brain with terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and an antibody directed to neuronal nuclear protein identified apoptotic neurons with high frequency in both traumatized rat cortex and hippocampus. Cytosolic extracts from injured cortex and hippocampus, but not from contralateral or control tissue, induced internucleosomal DNA fragmentation in isolated nuclei with temporal profiles consistent with those of DNA fragmentation observed in vivo. Caspase-3 mRNA levels, estimated by semiquantitative RT-PCR, were elevated fivefold in ipsilateral cortex and twofold in hippocampus by 24 hr after TBI. Caspase-1 mRNA content also was increased after trauma, but to a lesser extent in cortex. Increased caspase-3-like, but not caspase-1-like, enzymatic activity was found in cytosolic extracts from injured cortex. Intracerebroventricular administration of z-DEVD-fmk-a specific tetrapeptide inhibitor of caspase-3-before and after injury markedly reduced post-traumatic apoptosis, as demonstrated by DNA electrophoresis and TUNEL staining, and significantly improved neurological recovery. Together, these results implicate caspase-3-like proteases in neuronal apoptosis induced by TBI and suggest that the blockade of such caspases can reduce post-traumatic apoptosis and associated neurological dysfunction. 相似文献
1000.
On the basis of a review of neuropsychological evidence for several component processes of responding to global and local levels of hierarchically structured patterns, L. C. Robertson and M. R. Lamb (see record 1991-24938-001) hypothesized that interhemispheric communication between posterior cortexes would disrupt the typically interfering effects of global patterns on local response. These studies confirmed this hypothesis in 3 commissurotomized Ss. The normal interaction between visual field presentation and global or local level was present in normal Ss and all 3 patients, but global interference was absent or even reversed in patients. These data are discussed as they relate to the function of the corpus callosum and functional hemisphere asymmetries in responding to global and local levels of hierarchical forms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献