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21.
The time course of visual object categorization as a function of electrophysiological activity in the brain was investigated using a variant of the "oddball" design. Category level was manipulated by sequentially presenting subordinate, basic or superordinate target objects among a variety of non-target objects. It was found that superordinate categorizations were performed more quickly and differentiated from basic level categorizations in amplitude early in visual processing (320-420 ms). In contrast, subordinate categorizations took longer to perform and differentiated from basic level categorizations in amplitude and latency at later stages (450-550 ms). Notably, these effects were observed using the same objects categorized at different levels suggesting that visually categorizing objects at varying levels of abstraction engaged specific cognitive processes. These results are consistent with research on rapid visual categorization that challenges the generality of basic category level superiority effects. 相似文献
22.
We present a case illustrating the use of eye movement desensitization and reprocessing (EMDR) in the treatment of psychogenic seizures. These seizures were events lasting many hours, necessitating frequent emergency room visits and an extensive medical work up. Given the patient's history, posttraumatic stress disorder (PTSD) was diagnosed. EMDR is widely used as a treatment modality for PTSD, and the patient was referred for once-per-week treatment, with complete recovery after 18 months of therapy. The impact of her recovery on her quality of life was astonishing. This case supports the notion that EMDR can be an effective alternative treatment for psychogenic seizures, especially when the history reveals a traumatic event or abusive experiences. 相似文献
23.
Cancer outcomes research 总被引:1,自引:0,他引:1
24.
Selective glycogen synthase kinase 3 inhibitors potentiate insulin activation of glucose transport and utilization in vitro and in vivo 总被引:17,自引:0,他引:17
Ring DB Johnson KW Henriksen EJ Nuss JM Goff D Kinnick TR Ma ST Reeder JW Samuels I Slabiak T Wagman AS Hammond ME Harrison SD 《Diabetes》2003,52(3):588-595
Insulin resistance plays a central role in the development of type 2 diabetes, but the precise defects in insulin action remain to be elucidated. Glycogen synthase kinase 3 (GSK-3) can negatively regulate several aspects of insulin signaling, and elevated levels of GSK-3 have been reported in skeletal muscle from diabetic rodents and humans. A limited amount of information is available regarding the utility of highly selective inhibitors of GSK-3 for the modification of insulin action under conditions of insulin resistance. In the present investigation, we describe novel substituted aminopyrimidine derivatives that inhibit human GSK-3 potently (K(i) < 10 nmol/l) with at least 500-fold selectivity against 20 other protein kinases. These low molecular weight compounds activated glycogen synthase at approximately 100 nmol/l in cultured CHO cells transfected with the insulin receptor and in primary hepatocytes isolated from Sprague-Dawley rats, and at 500 nmol/l in isolated type 1 skeletal muscle of both lean Zucker and ZDF rats. It is interesting that these GSK-3 inhibitors enhanced insulin-stimulated glucose transport in type 1 skeletal muscle from the insulin-resistant ZDF rats but not from insulin-sensitive lean Zucker rats. Single oral or subcutaneous doses of the inhibitors (30-48 mg/kg) rapidly lowered blood glucose levels and improved glucose disposal after oral or intravenous glucose challenges in ZDF rats and db/db mice, without causing hypoglycemia or markedly elevating insulin. Collectively, our results suggest that these selective GSK-3 inhibitors may be useful as acute-acting therapeutics for the treatment of the insulin resistance of type 2 diabetes. 相似文献
25.
Taplin SH Barlow WE Ludman E MacLehos R Meyer DM Seger D Herta D Chin C Curry S 《Journal of the National Cancer Institute》2000,92(3):233-242
BACKGROUND: Prospective randomized trials have demonstrated that motivational telephone calls increase adherence to screening mammography. To better understand the effects of motivational calls and to maximize adherence, we conducted a randomized trial among women aged 50-79 years. METHODS: We created a stratified random sample of 5062 women due for mammograms within the Group Health Cooperative of Puget Sound, including 4099 women with prior mammography and 963 without it. We recruited and surveyed 3743 (74%) of the women before mailing a recommendation. After 2 months, 1765 (47%) of the 3743 women had not scheduled a mammogram and were randomly assigned to one of three intervention groups: a reminder post-card group (n = 590), a reminder telephone call group (n = 585), and a motivational telephone call addressing barriers group (n = 590). The telephone callers could schedule mammography. We used Cox proportional hazards models to estimate the hazard ratio (HR) and 95% confidence interval (CI) for documented mammography use by 1 year. RESULTS: Women who received reminder calls were more likely to get mammograms (HR = 1.9; 95% CI = 1.6-2.4) than women who were mailed postcards. The motivational and reminder calls (average length, 8.5 and 3.1 minutes, respectively) had equivalent effects (HR = 0.97; 95% CI = 0.8-1.2). After we controlled for the intervention effect, women with prior mammography (n = 1277) were much more likely to get a mammogram (HR = 3.4; 95% CI = 2.7-4.3) than women without prior use (n = 488). Higher income, but not race or more education, was associated with higher adherence. CONCLUSIONS: Reminding women to schedule an appointment was as efficacious as addressing barriers. Simple intervention groups should be included as comparison groups in randomized trials so that we better understand more complex intervention effects. 相似文献
26.
J R Taplin 《Journal of community psychology》1987,15(1):78-89
The current third-party fee-for-service mode of reimbursement for mental health services emphasizes individual, pathology-oriented intervention and thus has disadvantages for clients and carriers. This article focuses on the mode's effects on outpatient services for children, youth, and families. It examines the ways in which common payment modes seriously limit services and create an incentive for psychologists to take a narrow, often nonempirical, perspective. Suggestions that allow for multisystem, ecological skill building hinge on building relationships between psychologists and the carriers. Desired results take two forms: modification of contingencies between providers and carriers and modification of contingency between insured and carrier. Examples of each are presented. 相似文献
27.
Ovicidal activity and killing times were evaluated for six pediculicides, using viable eggs and recently fed head lice from infested children. Lice were continuously exposed to the products until death, and elapsed time was recorded. Eggs were immersed for ten minutes, rinsed, and dried. Four synergized pyrethrin products (RID, R&C Shampoo, A-200 Pyrinate Shampoo, A-200 Pyrinate Liquid) killed all lice in ten to 23 minutes, and 23% to 32% of treated eggs hatched; 0.5% malathion lotion (Prioderm Lotion) killed lice within five minutes and was highly ovicidal, with only 5% of eggs hatching. One percent lindane shampoo (Kwell Shampoo) was the slowest-acting pediculicide, requiring approximately three hours to kill all lice; 30% of the eggs hatched after treatment. The in vitro results for RID, Prioderm Lotion, and K well Shampoo were validated by clinical trials. 相似文献
28.
Using functional imaging, we investigated the effects of two different tasks on activation in the lateral occipital complex (LOC). Alternating blocks of intact and scrambled objects were presented. In one task, subjects responded when an object repeated (matching task). In a second task subjects silently named objects (naming task). Identical objects (tools, animals and letters) were presented for both tasks. A relative measure of the number of voxels activated in LOC in left and right hemispheres was calculated for each task across a range of thresholds. Also the effects of task demands on category specific areas in LOC were examined. The object matching task resulted in proportionally more activity in the right hemisphere. The object naming task resulted in proportionally more activity in the left hemisphere, most prominently in the anterior portion of LOC. Effectively, changing the task changed the lateralization of activation to intact objects in LOC. In contrast, changing the task did not change the lateralization of category-specific activations. The results suggest that there are task-related top-down influences on the activation of neural populations in LOC as a whole, but the lateralization of category-specific regions in LOC is independent of task demands and may reflect bottom-up processing. 相似文献
29.
30.
N K Hollenberg A Rivera T Meinking G Martinez M McCullough D Passan M Preston D Taplin M Vicaria-Clement 《Nephron》1999,82(2):131-138
BACKGROUND/AIMS: Among possible contributors to a progressive fall in renal perfusion and function with increasing age, some hypotheses have invoked the rise in blood pressure that occurs with age, and a high-protein diet typical of urban cultures. Kuna Amerinds residing in isolated islands off the Panamanian Coast have a very low protein intake and show no tendency for blood pressure to rise with age, thus providing an opportunity to test these hypotheses. METHODS: We measured renal plasma flow and glomerular filtration rate (PAH and inulin clearance) in 16 Kuna Indians ranging in age from 18 to 86 years (51 +/- 6 years) who have resided on Ailigandi, an isolated Panamanian island for all of their lives. Inulin and PAH were infused with a battery-driven pump for 60 min, and a metabolic clearance rate used to calculate inulin and PAH clearance. For comparison, we employed identical techniques in 29 residents of Boston, ranging in age from 19 to 79 years (52 +/- 4 years), all normotensive and free of disease or medication use. Twenty-four were Caucasian. RESULTS: The Bostonian controls showed the anticipated fall in PAH clearance with age (y = 806 - 4.9 x; r = -0.82; f = 38.0; p < 0.0001). Our hypothesis was that the absence of a blood pressure rise with age and the low protein intake would flatten the slope relating renal perfusion to Kuna age. Our finding was a numerically steeper slope relating age and renal plasma flow in the Kuna (y = 936 - 6.48x; r = -0.81; p < 0.001). Filtration fraction rose with age in both populations, and again the rise was steeper in the Kuna. GFR in the Kuna, on the other hand, was very much higher at any age (139 +/- 4 ml/min/1.73 m2) than in Bostonians (112 +/- 3 ml/min/1.73 m2; p < 0.001). CONCLUSION: The findings are not in accord with the hypothesis that age-related changes in renal perfusion and glomerular filtration rate reflect an important contribution from blood pressure rise and a high protein intake, typical of modern, urban life. 相似文献