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91.
Repetition priming denotes a behavioural change caused by prior exposure to a stimulus. The effect is known to last for weeks. This study addresses the underlying neural mechanisms for very-long-term picture priming by using event-related functional magnetic resonance imaging complemented by a behavioural paradigm. Previous functional imaging studies with shorter retention intervals have shown that priming is associated with changes in the activity of both the occipital and posterior temporal cortex. In this study we compared retention intervals of 1 day and 6 weeks after initial exposure to a picture stimulus. Priming-related decreases in cortical activity in posterior extrastriate and dorsal left inferior frontal areas were found only for the shorter retention interval. In contrast, fMRI activation in the inferior posterior temporal and anterior left inferior frontal cortex was reduced following priming for both retention intervals. In the behavioural paradigm, the priming effect was stable over time. We conclude that the left inferior frontal and inferior posterior temporal cortex play a key role in the very-long-term priming effect.  相似文献   
92.
Loss of cortical gray matter is accompanied by a commensurate increase in the sulcal and intraventricular cerebrospinal fluid volume. On diffusion-weighted magnetic resonance imaging, this would be reflected as a higher apparent diffusion coefficient in affected brain regions. On the basis of the above premise, we suggest that the apparent diffusion coefficient may be used as a surrogate marker for the assessment of regional brain volume deficits. We demonstrate this approach by voxelwise analysis of registered apparent diffusion coefficient images from a group of 15 patients with schizophrenia and 15 age-matched healthy controls. We found widespread regional apparent diffusion coefficient increases in patients. Affected areas included the bilateral insular cortex, hippocampus, temporal lobe, and occipital areas. These results largely concur with previous findings of cortical volume deficits in schizophrenia.  相似文献   
93.
Rotigotine is a new dopamine agonist with transdermal patch formulation for the treatment of Parkinson disease. The aim of this study was to investigate safety and efficacy of rotigotine in patients with early-stage Parkinson disease. In this open-label, dose-escalation, safety and efficacy study, 31 patients in the early stages of idiopathic Parkinson disease received rotigotine to a maximum of 18.0 mg/day. Of the 29 patients who completed the 28-day treatment phase, 24 were maintained at the maximum dose level. The drug was well tolerated, and skin reactions were mild. A statistically significant improvement in UPDRS I, II, and III scores was observed from baseline to end of treatment for the 29 subjects who completed the trial. Mean improvement (+/- standard deviation) was -0.41 +/- 0.78 on UPDRS I (P = 0.0078), -2.76 +/- 3.31 on UPDRS II (P = 0.0001), and -4.62 +/- 5.32 on UPDRS III (P < 0.0001). When results were stratified by maximum dose achieved, significant improvements were seen on all 3 subscores for patients achieving the maximum dose. These data suggest that rotigotine is a safe, well-tolerated, and effective treatment for early-stage Parkinson disease.  相似文献   
94.
This is an open study to compare the cure rate of cutaneous leishmaniasis caused by L. major and treated with either paromomycin sulfate or intralesional injection of meglumine antimoniate. Sixty parasitologically proven cases with 1-3 lesions were included and divided randomly into two equal groups; one group received 1 ml of meglumine antimonate intradermally every other day for 20 days, the other group received the ointment containing 15% parmomycin sulfate in urea twice daily for 20 days. The patients were clinically evaluated at 1 and 6 weeks after treatment was completed. The results of clinical evaluation at 1 week after treatment completed showed a cure rate of 18 out of 27 (66%) in the meglumine antimonate injected group and 20 out of 29 (68%) in the paromomycin sulfate treated group. The chi square test was used to compare the cure rate between the two groups and showed no significant difference (p = 0.85).  相似文献   
95.
96.
Pharmacologic inhibition of indoleamine 2,3 dioxygenase (IDO) activity during murine pregnancy results in rejection of allogeneic fetuses by the maternal immune system. Here, we show that IDO expression is restricted to perinuclear regions of primary trophoblast giant cells (TGCs) of fetal origin at mid-gestation (E10.5). After placentation (E14), no IDO expression was detected at the maternal-fetal interface. Matings involving IDO-deficient females revealed that paternally inherited IDO alleles were inactive in primary TGCs, presumably due to paternal genome-specific gene inactivation. Allogeneic matings in which both parents were genetically IDO-deficient produced litters of normal sizes at normal rates compared to IDO-sufficient parental mice, implying that compensatory or redundant immunosuppressive mechanisms protected allogeneic fetuses during gestation in IDO-deficient mice. Consistent with this notion, treatment with IDO inhibitor did not affect allogeneic pregnancy rates when both parents were IDO-deficient, confirming that IDO was the relevant pharmacologic target of the IDO inhibitor in matings involving IDO-sufficient mice. Hence, IDO is a key immunosuppressive mechanism in normal murine pregnancies, and it is regulated entirely through maternally inherited fetal genes.  相似文献   
97.
OBJECTIVE: To determine the prevalence and morphologic helical computed tomography (CT) features of peripancreatic vascular abnormalities in patients with acute pancreatic inflammatory disease in correlation with the severity of the pancreatitis. MATERIALS AND METHODS: One hundred and fifty-nine contrast-enhanced helical CT scans of 100 consecutive patients with acute pancreatitis were retrospectively and independently reviewed by three observers. CT scans were scored using the CT severity index (CTSI): pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the CT severity index and the presence of peripancreatic vascular abnormalities was calculated (K-statistic). Correlation between the prevalence of complications and the degree of pancreatitis was estimated using Fisher's exact test. RESULTS: The severity of pancreatitis was graded as mild (n = 59 scans), moderate (n = 82 scans), and severe (n = 18 scans). Venous abnormalities detected included splenic vein (SV) thrombosis (31 scans, 19 patients), superior mesenteric vein (SMV) thrombosis (20 scans, 14 patients), and portal vein (PV) thrombosis (17 scans, 13 patients). Arterial hemorrhage occurred in five patients (6 scans). In our series, no cases of arterial pseudoaneurysm formation were detected. The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of major vascular abnormalities was 75.5-79.2 and 86.2-98.8%, respectively. The presence of the vascular abnormalities in correlation with the severity of pancreatitis was variable. CONCLUSION: Vascular abnormalities are relatively common CT findings in association with acute pancreatitis. The CT severity index is insufficiently accurate in predicting some of these complications since no statistically significant correlation between their prevalence and the severity of pancreatitis could be established.  相似文献   
98.
Arthrodesis of the Charcot foot and ankle   总被引:1,自引:0,他引:1  
The unstable Charcot foot remains a challenge to even the most experienced surgeon. Reconstructive surgical management of the neuropathic Charcot foot is a valuable treatment option for the patient who has severe musculoskeletal deformity. Frequently, the unstable nature of this deformity prevents successful use of therapeutic shoes or braces. For these high-risk individuals, reconstructive surgery often is the only way to avoid amputation. With precise surgical technique, appropriate postoperative care, and meticulous patient compliance, stability can be restored to the dysfunctional foot. The management of the Charcot foot can be extremely rewarding for the patient and surgeon.  相似文献   
99.
A selective, sensitive and robust capillary electrophoresis (CE) method has been developed and validated for multi analysis of ragaglitazar (also known as NNC 61-0029 or DRF 2725) and its counter ion arginine in Active Pharmaceutical Ingredients (API) and low-dose tablets (0.5, 1.0 and 2.0 mg). The method covers a total number of 12 analyses for the API and tablets: assay and identification of ragaglitazar and arginine, chiral purity of ragaglitazar and purity of ragaglitazar. After a simple extraction of samples with acetonitrile and 0.01 M sodium hydroxide (10:90), separation was performed using a combination of two cyclodextrins; sulfobutylether-beta-cyclodextrin (SB-beta-CD) and dimethyl-beta-cyclodextrin (DM-beta-CD) in the electrolyte. The method showed good specificity and could separate and detect ragaglitazar, the distomer (the (+)-enantiomer) and arginine. The LOQ was found to be 0.10%, corresponding to 0.2 ng (0.5 microg/ml) for ragaglitazar and the distomer. Linearity was observed to be from 0.5 to 15 microg/ml (range 0.2-60 ng) and 400-600 microg/ml (range 1603-2404 ng) for ragaglitazar and 166-250 microg/ml (range 668-1000 ng) for arginine. The accuracy (as percent recovery) for ragaglitazar was found to be 101-106% (at 400-600 microg/ml), 101-125% (at 0.5-15 microg/ml) and for arginine 97-101% (at 166-250 microg/ml). The repeatability for the detection of peaks as R.S.D. was found to be as follows, ragaglitazar: 0.05%, distomer: 1.01%, largest single impurity: 5.84%, total impurities: 0.90% and arginine: 2.00%. The intermediate precision for the detection of peaks as R.S.D. was found to be as follows, ragaglitazar: 0.63%, distomer: 1.98%, largest single impurity: 5.22%, total impurities: 13.17% and arginine: 3.50.  相似文献   
100.
OBJECTIVE: This study was undertaken to evaluate the impact of a pelvic dissection course on resident proficiency in surgical anatomy. STUDY DESIGN: Over a 1-year period, residents attended a course consisting of pretesting and posttesting, lectures, and pelvic dissection. Tests results were analyzed using paired Student t test, analysis of variance, and Kruskal-Wallis statistics. RESULTS: Of 42 residents, 24 completed all testing (study cohort). On written and practical examinations, resident scores improved a median of 42% and 29% (both P<.0001). Postgraduate year (PGY) 2 demonstrated the greatest improvement on the practical and PGY-3s demonstrated the greatest improvement on the written. Baseline written and practical results discriminated PGY level (construct validity): PGY-2=PGY-3相似文献   
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