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51.
Study ObjectiveTo compare preoperative transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI) with intraoperative ultrasound (IOUS) in surgeons first learning to use this technique.DesignA prospective study of IOUS accuracy for mapping the size and location of myomas compared with TVUS or MRI (Canadian Task Force classification II-2).SettingFive University of California academic centers (Davis, Irvine, Los Angeles, San Diego, and San Francisco).PatientsTwenty-six premenopausal women seeking uterine-sparing surgical treatment of myomas. Eligible participants could have no more than 6 myomas ≥2 cm and <10 cm and a uterine size no larger than 16 weeks by pelvic examination.InterventionsMeasurement of myomas by IOUS followed by radiofrequency ablation (RFA) of fibroids.Measurements and Main ResultsEligible participants had to have imaging with TVUS or MRI within the last year to assess myoma characteristics. During the RFA operation, surgeons who had undergone a 1-day training on RFA and IOUS measured all myomas visualized with IOUS. Surgeons measured more myomas than were reported on MRI (12 on MRI and 16 on IOUS) or TVUS (41 on TVUS and 62 on IOUS) in all positions (anterior, posterior, lateral, and fundal). In particular, they identified more myomas <2 cm (4 on MRI, 9 on IOUS, 1 on TVUS, and 19 on IOUS). They located 2.3 times as many myomas in the anterior position as TVUS. For the myomas ≥2 cm identified by IOUS and MRI or IOUS and TVUS, there was no statistically significant difference in the mean myoma number or the mean myoma diameter measurements.ConclusionSurgeons first learning to use IOUS detect the same number of myomas ≥2 cm as identified by TVUS and MRI and find a greater number of myomas <2 cm on IOUS compared with radiologist-reported TVUS.  相似文献   
52.
Immunologic Research - Obesity, a morbid condition snowballing in the world, may cause many health issues in healthy and ill people. Many disorders are known to be influenced by obesity, mainly in...  相似文献   
53.
Animal models of hearing loss and tinnitus observe pathological neural activity in the tonotopic frequency maps of the primary auditory cortex. Here, we applied ultra high-field fMRI at 7 T to test whether human patients with unilateral hearing loss and tinnitus also show altered functional activity in the primary auditory cortex. The high spatial resolution afforded by 7 T imaging allowed tonotopic mapping of primary auditory cortex on an individual subject basis. Eleven patients with unilateral hearing loss and tinnitus were compared to normal-hearing controls. Patients showed an over-representation and hyperactivity in a region of the cortical map corresponding to low frequencies sounds, irrespective of the hearing loss and tinnitus range, which in most cases affected higher frequencies. This finding of hyperactivity in low frequency map regions, irrespective of hearing loss range, is consistent with some previous studies in animal models and corroborates a previous study of human tinnitus. Thus these findings contribute to accumulating evidence that gross cortical tonotopic map reorganization is not a causal factor of tinnitus.  相似文献   
54.
Acute stress can exert beneficial or detrimental effects on different forms of cognition. In the present study, we assessed the effects of acute restraint stress on different forms of cost/benefit decision-making, and some of the hormonal and neurochemical mechanisms that may underlie these effects. Effort-based decision-making was assessed where rats chose between a low effort/reward (1 press=2 pellets) or high effort/reward option (4 pellets), with the effort requirement increasing over 4 blocks of trials (2, 5, 10, and 20 lever presses). Restraint stress for 1 h decreased preference for the more costly reward and induced longer choice latencies. Control experiments revealed that the effects on decision-making were not mediated by general reductions in motivation or preference for larger rewards. In contrast, acute stress did not affect delay-discounting, when rats chose between a small/immediate vs larger/delayed reward. The effects of stress on decision-making were not mimicked by treatment with physiological doses of corticosterone (1–3 mg/kg). Blockade of dopamine receptors with flupenthixol (0.25 mg/kg) before restraint did not attenuate stress-induced effects on effort-related choice, but abolished effects on choice latencies. These data suggest that acute stress interferes somewhat selectively with cost/benefit evaluations concerning effort costs. These effects do not appear to be mediated solely by enhanced glucocorticoid activity, whereas dopaminergic activation may contribute to increased deliberation times induced by stress. These findings may provide insight into impairments in decision-making and anergia associated with stress-related disorders, such as depression.  相似文献   
55.
BACKGROUND: One of the most challenging problems in clinical surgery is management of injured duodenum. In this experimental study, we treated large duodenal defects by an expanded polytetrafluoroethylene (ePTFE, Gore-Tex; W.L. Gore, Elkton, MD) soft-tissue patch and compared it with the jejunal serosal patch. MATERIALS AND METHODS: A duodenal defect (about 50% of the total circumference) was created in the second portion of the duodenum in 20 dogs. The effectiveness and gross and histological examinations of the ePTFE patch technique was compared with the jejunal serosal patch. RESULTS: No significant difference was found in early survival rates (90.9% versus 88.9%; P = 0.711). The whole grafted area was covered by neomucosa at the end of the sixth week in all animals with the ePTFE patch. The scar was small; no significant narrowing of lumen was noted and serosal healing was uniformly complete. In histological examination, complete coverage of the ePTFE grafts by neomucosa consisting of columnar epithelium with short villous formations was observed. CONCLUSION: Use of the ePTFE patch method is easy, reliable, and comparable to the jejunal serosal patch. It can be used in the treatment of large duodenal defects, which cannot be repaired by duodenorraphy.  相似文献   
56.
Human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic inflammatory myelopathy. The pathophysiology of HAM/TSP is not yet fully understood; therefore, effective therapy remains a challenging issue. This study was designed to evaluate the efficacy of interferon-alpha (IFN-α) in HAM/TSP patients in the Northeast of Iran. Forty-nine patients with a definite diagnosis of HAM/TSP were enrolled in this clinical trial. For six months, the patients received three million international units of subcutaneous IFN-α-2b per each injection. The dose regimen was daily injection for the first month, three times administration per week for the months 2 and 3, twice weekly injection for the months 4 and 5 and weekly injection for the sixth month. The clinical and laboratory responses were evaluated based on neurologic examinations and immunovirological markers. IFN-α had significant but temporary effect on the motor and urinary functions of the patients. Comparing to the baseline values, proviral load was significantly decreased one month after treatment in responders (495.20±306.87 to 262.69±219.24 p=0.02) and non-responders (624.86±261.90 to 428.28±259.88 p=0.03). Anti-HTLV-1 antibody titers were significantly decreased among responders (1152.1±200.5 to 511.6±98.2 p=0.009) and non-responders (1280.1±368.1 to 537.6±187 p=0.007). Flow cytometry showed no significant changes in CD4, CD8, CD4CD25 and CD16CD56 counts with IFN-α. The positive impact of IFN-α was observed during the treatment period with significant effects on some clinical aspects of HAM/TSP.  相似文献   
57.
Few studies have explored the associations of reported PA (RPA) with the processes underlying the development of disability. The present study was performed to explore RPA among older persons and its association with onset of functional dependence and mortality. Among a probability sample of 1782 community-living persons, aged 75-83 years, we evaluated the 1021 who reported no disability in basic activities of daily living. Participants were followed for a median of 8.34 years in public registers to determine onset of disability and mortality. RPA predicted mortality in older women (HR=1.77, 95%CI=1.42-2.19) and men (HR=1.65, 95%CI=1.27-2.14) over long time intervals. The effect of RPA persisted among permanently disabled older women, after adjusting for age, baseline vulnerability and grade of disability. Low RPA was independently associated with risk of incident disability (HR=1.56, 95%CI=1.10-2.23) in men. Among older women, the association between RPA and incidence of disability was attenuated in analyses that controlled for baseline mobility function. Thus, the association between physical activity and mortality reflected processes different from those underlying a simple relation between physical activity, disability and mortality. Physical activity was an ubiquitous predictor of longevity, but only for women.  相似文献   
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59.
Abstract Behcet's disease is a multisystem disorder and classified as “vasculitic syndrome with a wide variety of clinical manifestations.” Cardiac involvement is very rare but can occur with different presentations including: pericarditis, cardiomyopathy, endocarditis, endomyocardial fibrosis, intracavitary thrombosis, and coronary artery disease. Great vessel involvement is more common. Recurrent Phlebitis, commonly involving large vessels (superior vena cava, inferior vena cava, hepatic veins) and cerebral veins are the sole presentation in this regard. Arterial involvement is expressed by aneurysm or pseudoaneurysmal formation. Due to the wide variety of cardiovascular manifestations and the resulting high mortality, cardiac surgeons should be familiar with this disease. In this paper we review the articles and introduce our four cases presenting with aneurysm of ascending aorta with free aortic insufficiency, aneurysm of descending aorta, pulmonary artery aneurysm, and pseudoaneurysm of aortic arch.  相似文献   
60.
We aimed to summarize the available evidence on cerebral blood flow (CBF) changes in normal aging and common cognitive disorders. We searched PubMed for studies on CBF changes in normal aging and cognitive disorders up to 1 January 2019. We summarized the milestones in the history of CBF assessment and reviewed the current evidence on the association between CBF and cognitive changes in normal aging, vascular cognitive impairment (VCI) and Alzheimer’s disease (AD). There is promising evidence regarding the utility of CBF studies in cognition research. Age-related CBF changes could be related to a progressive neuronal loss or diminished activity and synaptic density of neurons in the brain. While a similar cause or outcome theory applies to VCI and AD, it is possible that CBF reduction might precede cognitive decline. Despite the diversity of CBF research findings, its measurement could help early detection of cognitive disorders and also understanding their underlying etiology.  相似文献   
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