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51.
Jody Tanabe Jason R Tregellas Laura F Martin Robert Freedman 《Neuropsychopharmacology》2006,59(8):754-761
BACKGROUND: Abnormal smooth pursuit eye movement (SPEM) in schizophrenic patients is a well known phenomenon, but the neurophysiological mechanisms underlying the deficit are unknown. Nicotine temporarily improves SPEM and has been associated with reduced hippocampal hemodynamic activity in schizophrenics. Nicotine's effect on brain activity in control subjects performing SPEM has not been studied. The purpose of this work was to determine if nicotine differentially affects brain activity in schizophrenic and control subjects during pursuit eye tracking. METHODS: 16 subjects with schizophrenia and 16 control subjects underwent functional MR imaging during SPEM after receiving placebo or nicotine gum. Four brain regions were analyzed for main effects of group, drug, and interactions: hippocampus, cingulate gyrus, frontal eye fields, and area MT. RESULTS: Nicotine reduced hippocampal activity in both groups, but the effect was greater in control subjects. A group by drug interaction was observed in the anterior cingulate gyrus, where nicotine decreased activity in control subjects and increased activity in schizophrenic subjects. There were no significant effects of group, drug, or interactions in frontal eye fields or area MT. CONCLUSIONS: Nicotine may improve SPEM performance in people with schizophrenia through cholinergic stimulation of the hippocampus and cingulate gyrus. Potential mechanisms include improved inhibitory function and attention. 相似文献
52.
Margaret Seto-Poon Melanie Madronio Jason P Kirkness Terence C Amis Karen Byth Chong Lee Lim 《Clinical neurophysiology》2005,116(5):1172-1180
OBJECTIVE: To examine response decrement of the recently reported inspiratory skin conductance response (SCR) [Lim CL, Seto-Poon M, Clouston PD, Morris JG. Sudomotor nerve conduction velocity and central processing time of the skin conductance response. Clin Neurophysiol 2003;114:2172-80]. METHODS: Twelve healthy adult volunteers performed 3 tasks (A) a control task of maintaining tidal breathing and then two randomized tasks, (B) a deep inspiration to a target oral pressure and (C) tapping with a finger. Each task was performed 30 times on cue every 20s in 3 runs with 5 min of rest between runs. The SCR, oral pressure, airflow, inspired volume and cue signal were recorded continuously and analysed offline. SCR amplitude was logarithmically transformed and then statistically analysed, using a linear mixed effects model, as a function of run number, trial number and absolute error between target and actual oral pressures. RESULTS: Inspiratory efforts elicited exponentially decreasing SCR amplitude with increasing trial number during each run (P < 0.0001). After adjusting for trial number, the mean SCR amplitude of the second and the third run were, respectively, 24.2 (95% CI (0.175, 0.336), P < 0.001) and 14.4% (95% CI (0.104, 0.200), P < 0.001) of the first run amplitude. CONCLUSIONS: Volitional deep inspiration reliably activates an SCR that exhibits response decrement with repetition, which may be habituation. SIGNIFICANCE: The volitional inspiratory SCR may assist in the assessment of sympathetic autonomic status in patients with peripheral afferent neuropathy. 相似文献
53.
James D Fogarty Jason M Hafron David M Hoenig Reza Ghavamian 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(2):199-204
OBJECTIVES: Nephron-sparing surgery has emerged as the treatment of choice for the incidentally detected small renal mass, especially those less than 4 cm in size. We describe our technique and experience with the laparoscopic excision of these lesions. METHODS: Between June 2001 and October 2003, 20 patients underwent nephron-sparing surgery at our institution. Twenty-one laparoscopic partial nephrectomy procedures were performed. All tumors were detected incidentally by cross-sectional imaging. All patients had a solid renal mass or a complex cystic renal mass of Bosniak category III or greater. All solid tumors were exophytic and less than 4cm in diameter. Both transperitoneal and retroperitoneal approaches were used. Hemostasis was achieved without hilar control in 20 of the 21 cases. RESULTS: Twenty renal units were approached transperitoneally, and 1 retroperitoneally. Mean tumor size was 2.6 cm (range, 1.2 to 4). Mean estimated blood loss was 211 mL (range, 50 to 500), and mean operative time was 165 minutes. Pathology revealed renal cell carcinoma in 14 (70%). No intraoperative complications occurred. Two patients required blood transfusions postoperatively. CONCLUSION: Carefully selected patients with small, exophytic renal masses can safely undergo laparoscopic excision. When achievable, this procedure can be a more logical alternative to ablative techniques for the minimally invasive management of such lesions. 相似文献
54.
Mohammad Khalid Jamal M.D. Eric J. DeMaria M.D. Jason M. Johnson D.O. Brennan J. Carmody M.D. Luke G. Wolfe M.S. John M. Kellum M.D. Jill G. Meador R.N. 《Surgery for obesity and related diseases》2005,1(6):655-516
BACKGROUND: We hypothesized that major co-morbidities affect survival and complications after gastric bypass. METHODS: A total of 1465 patients undergoing laparoscopic and open gastric bypass between 1995 and 2002 were studied. Patients with a body mass index >or= 35 kg/m(2) and major co-morbidities (group 1, n = 1045) were compared with patients with a body mass index >or= 40 kg/m(2) with minor/no co-morbidities (group 2, n = 420). RESULTS: Group 1 patients were older (43 versus 36 years, P < 0.001) and had a greater BMI (53 versus 50 kg/m(2), P < 0.001). Early postoperative complications were greater in group 1 than in group 2 and included leaks (4.1% versus 1.2%, P < 0.0032) and wound infections (3.9% versus 1.4%, P < 0.0133). Procedure-related mortality in the series was 1.7%. Mortality was 10-fold greater in group 1 (2.3% versus 0.2%, P < 0.0032). The incidence of small bowel obstruction, incisional hernia, and pulmonary embolism was similar in the two groups. Excess weight loss was significantly greater in group 2 (68% versus 62%, P < 0.001) at 1 year. Resolution of group 1 co-morbidities was great, including hypertension in 62%, diabetes in 75%, venous stasis disease in 96%, and pseudotumor cerebri in 98%. CONCLUSION: Outcomes analysis of obesity surgery requires risk stratification. The very low mortality rates in published studies are likely explained by surgical treatment of low-risk patients with minor co-morbidities, such as those seen in group 2. However, despite the increased perioperative risk, the group 1 patients (with major co-morbidities) demonstrated dramatic resolution of their co-morbid conditions, justifying the decision to go forward with surgery. The data support a radical change in treatment philosophy in which morbidly obese individuals should be offered bariatric surgery before major co-morbid conditions develop as a strategy to decrease the operative risk. 相似文献
55.
Effects of gastric bypass procedures on bone mineral density,calcium, parathyroid hormone,and vitamin d 总被引:2,自引:0,他引:2
Jason M. Johnson James W. Maher Isaac Samuel Deborah Heitshusen Cornelius Doherty Robert W. Downs 《Journal of gastrointestinal surgery》2005,9(8):1106-1111
Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data
on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals
after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic
preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had
or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by
9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n =
14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year,
by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the
operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS)
by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS)
and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively
(25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the
first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the
first year.
Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18,
2005 (oral presentation). 相似文献
56.
57.
Vivek N Ahya Alden M Doyle James D Mendez David A Lipson Jason D Christie Emily A Blumberg Alberto Pochettino Linda Nelson Roy D Bloom Robert M Kotloff 《The Journal of heart and lung transplantation》2005,24(7):932-935
Chronic rejection is the major hurdle to long-term survival after lung transplantation. Endobronchial infection with Pseudomonas aeruginosa is common in patients with chronic rejection and this may further contribute to deterioration of the allograft. Inhaled tobramycin is commonly used to treat P aeruginosa airways infection in patients with cystic fibrosis. The safety of inhaled tobramycin in transplant recipients, however, has not been established. We describe the first report of a lung transplant recipient who developed renal failure and vestibular injury after receiving inhaled tobramycin. We review the literature regarding the safety of inhaled tobramycin and discuss potential mechanisms that may promote systemic toxicity in transplant recipients. 相似文献
58.
We present a comprehensive, meta‐analytic review and critical evaluation of outcome research pertaining to the effectiveness of premarital prevention programs. Results revealed that the mean effect size for premarital programs was .80, which means that the average person who participated in a premarital prevention program was significantly better off afterwards than 79% of people who did not participate. Stated differently, the average participant in a premarital program tends to experience about a 30% increase in measures of outcome success. Our findings suggest that premarital prevention programs are generally effective in producing immediate and short‐term gains in interpersonal skills and overall relationship quality and that these improvements are significantly better than nonintervention couples in these areas. However, because of a lack of extended follow‐up research, conclusions about long‐term effectiveness remain elusive. We propose implications for future research, education, and policy. 相似文献
59.
Daniel le Grange Jason Tibbs Timothy D. Noakes 《The International journal of eating disorders》1994,15(4):369-376
Competitive pressures to achieve a slim body shape may be of importance in the etiology of eating disorders in ballet dancers. This study examines the presence of anorexia nervosa-like symptoms in a group of 49 female ballet students (mean age = 18.9 years, SD ± 1.9). All students were assessed for certain physical (weight and height) and psychological (Eating Attitude Test [EAT]) indices at the start of their academic training year. Thereafter, all subjects who presented with anorexia nervosa-like symptoms (EAT ≥ 30, and/or with current secondary amenorrhea or primary amenorrhea if aged 16 years or over) at the initial assessment, were invited for a semistructured interview (Morgan-Russel scales) to determine their diagnostic status. Another aim of the study was to assess the prognostic implications of a diagnosis of anorexia nervosa in this sample. All subjects previously interviewed were invited for a follow-up assessment at 10 months. Anorexia nervosa could be diagnosed in 2 students (4.1%), whilst another 4 students (8.2%) presented with “partial syndrome” anorexia nervosa. All diagnosed students managed to complete their academic training year. The development and implications of a diagnosis of anorexia nervosa in the ballet students are discussed. 相似文献
60.