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1.
Introduction: This study investigated variables associated with subjective decline in executive function among Veterans of Operations Enduring Freedom, Iraqi Freedom, and New Dawn (OEF/OIF/OND) following a history of blast-related mild traumatic brain injury (mTBI).

Method: Fifty-six male U.S. Veterans (MAge = 35.3 ± 8.8 years) with a history of blast-related mTBI (6.6 ± 3.2 years post injury) completed a battery of self-report questionnaires and neuropsychological measures. Participants rated current and retrospectively estimated pre-mTBI executive function difficulties on the Frontal Systems Behavior Scale (FrSBe). A difference score (post- minus pre-mTBI ratings) was the dependent variable (?FrSBe). Linear regression models examined variables predicting ?FrSBe, including: pre-injury characteristics (education, premorbid intelligence), injury-related characteristics (number of blast exposures, losses of consciousness), post-injury clinical symptoms (PTSD Checklist–Military version; Pittsburgh Sleep Quality Index), and post-injury neuropsychological performances on executive function measures (Trail Making Test Part B; Controlled Oral Word Association Test; Auditory Consonant Trigrams; Wisconsin Card Sorting Test).

Results: While 11% of participants had a clinically elevated pre-injury FrSBe total score, 82% had a clinically elevated post-injury FrSBe total score. Only self-reported PTSD symptom severity independently predicted perceived change in executive function.

Conclusions: Many OEF/OIF/OND Veterans with a history of blast-related mTBI experience subjective decline in executive function following injury. Perceived executive function decline was associated with higher PTSD symptom severity, aligning with previous research associating PTSD with cognitive complaints. Results did not support a correspondence between perceived cognitive change and neuropsychological performances.  相似文献   
2.
In der Behandlung von Frakturen spielt die Analgesie eine wesentliche Rolle. Es stellt sich daher die Frage, ob in der Klinik h?ufig eingesetzte Analgetika wie Tramadol oder Diclofenac negative Wirkungen auf die Knochenbruchheilung haben.  相似文献   
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Zusammenfassung In einem pulsatil mit Kochsalz durchströmten Modell der Femoralisgabel wurden Flussmessungen und Druckgradienten für Flussmengen von 170 bis 860 ml/min bei peripheren Widerständen von 232 bis 25 792 dyn s cm–5 über dem Superficialis- und Profundaabgang bei Stenosen von 1 cm Länge und Querschnittsverminderungen von 0% bis 100% gemessen. Bei grossen Flussmengen (800–860 ml/min) und kleinem peripheren Widerstand (<640 dyn s cm–5) lag die kritische Stenose am Profundaabgang bei 4,1 mm Durchmesser, für hohe periphere Widerstände (> 5 072 dyn s cm–5) bei 2,6 mm; bei kleinen Flussmengen (<400 ml/min) betrug der kritische Durchmesser 1,8 mm. Der nicht stenosierte Profundaabgang stellte für keine der Versuchsbedingungen ein strömungsdynamisches Hindernis dar.  相似文献   
4.
Blood flowing through a prosthetic heart valve can be damaged by flow-induced shear forces. Fluid dynamics variables and geometric factors play an important role in the evaluation of shear-stress-related blood damage. Central-flow prosthetic valves have been considered as an optimal replacement for mechanical and biological valves. Recently it was shown that shear stress distribution along the surface of a polyurethane cusp reaches values that can damage the blood elements. A mathematical model correlating the effects of shear stresses on blood corpuscles with clinical findings was employed in vitro. The model can be applied to the effects of blood-surface interaction and is of clinical relevance.  相似文献   
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A 45-year-old woman with history of iritis, uveitis, and sarcoidosis of the skin presented with a subacute cervical myelopathy. Magnetic resonance imaging (MRI) ;howed patchy, multifocal, gadoliniumenhancing intramedullary lesions of the spinal cord, and extramedullary lesions of the basal cisterns and fourth ventricle. Symptoms and MRI abnormalities were improved within 1 month of corticosteroid therapy.  相似文献   
9.
Knowledge of the response of the primary visual cortex to the various spatial frequencies and orientations in the visual scene should help us understand the principles by which the brain recognizes patterns. Current information about the cortical layout of spatial frequency response is still incomplete because of difficulties in recording and interpreting adequate data. Here, we report results from a study of the cat primary visual cortex in which we employed a new image-analysis method that allows improved separation of signal from noise and that we used to examine the neurooptical response of the primary visual cortex to drifting sine gratings over a range of orientations and spatial frequencies. We found that (i) the optical responses to all orientations and spatial frequencies were well approximated by weighted sums of only two pairs of basis pictures, one pair for orientation and a different pair for spatial frequency; (ii) the weightings of the two pictures in each pair were approximately in quadrature (1/4 cycle apart); and (iii) our spatial frequency data revealed a cortical map that continuously assigns different optimal spatial frequency responses to different cortical locations over the entire spatial frequency range.  相似文献   
10.
Extended soft tissue defects after extensive deep burns or tumor resections are still an unresolved problem in plastic and reconstructive surgery. There is a clinical need for an adequate solution to this problem but currently, no adequate implant material is available for the correction of these defects. Since the autologous transplantation of mature adipose tissue gives poor results, this study explores the advantages of using human preadipocytes in collagen sponges for tissue reconstruction purposes. Human preadipocytes of young adults were isolated, cultured, seeded onto collagen sponges with uniform pore size, and implanted into immunodeficient mice. After 24 hours of incubation in vitro and after explantation at 3, 8, and 12 weeks, sponges were examined for macroscopic appearance, weight, thickness, histology, immuno-histochemistry, and ultrastructure. We find good penetration of cells into the scaffold, layers of adipose tissue, and new vessels on all grafts while controls appear unchanged. These results are promising for improving the reconstruction of soft tissue defects.  相似文献   
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