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991.
Thirty children undergoing cardiac surgery under cardiopulmonary bypass (CPB) were prospectively studied to assess beneficial effects of modified ultrafiltration (MUF) over and above conventional ultrafiltration (CUF). Transoesophaegeal echocardiography determined ejection fraction (EF), fractional area change (FAC) and posterior wall thickness in end-diastole and end-systole were measured and compared in two groups undergoing CUF (group I) and CUF plus MUF (group II). Haemodynamic data, haematocrit, temperature drift, postoperative chest tube drainage in first 48 hours, ventilation and intensive care unit (ICU) stay were also recorded. Within group data were analysed by general linear trend and intergroup comparisons were made with t-test. EF and FAC decreased at 0 min after CPB in both groups, but both recovered at 10 and 30 min after CPB in group II. Increase in EF and FAC in group II was about 12-15 % and 3-5 % from 0 min respectively. There was also significant improvement in posterior wall thickness and haematocrit (P<0.05) in group II. Patients in group II maintained better systolic blood pressure and heamoglobin after CPB. Chest tube drainage in first 48 hours was significantly less in group 1I (100 -18 verses 85 +/-20 ml, P<0.05), but ventilation and ICU stay were not different between the two groups. Combined ultrafiltration has beneficial effect an haemodynamics with improvement in EF and FAC. It improves haematocrit and decreases chest pulse drainage.  相似文献   
992.
993.
994.
Schizophrenia patients show a disconnection in amygdala-medial prefrontal cortex and autonomic arousal systems for processing fear. Concurrent functional magnetic resonance imaging [fMRI] and skin conductance recording were used to determine whether these disturbances are specific to fear, or present in response to other signals of danger. We also examined whether these disturbances distinguish a specific symptom profile. During scanning, 27 schizophrenia (13 paranoid, 14 nonparanoid) and 22 matched healthy control subjects viewed standardized facial expressions of fear, anger and disgust (versus neutral). Skin conductance responses [SCRs]were acquired simultaneously to assess phasic increases in arousal. 'With-arousal' versus 'without-arousal' responses were analysed using non-parametric methods. For controls, 'with-arousal' responses were associated with emotion-specific activity for fear (amygdala), disgust (insula) and anger (anterior cingulate), together with common medial prefrontal cortex [MPFC] engagement, as predicted. Schizophrenia patients displayed abnormally increased phasic arousal, with concomitant reductions in emotion-specific regions and MPFC. These findings may reflect a general disconnection between central and autonomic systems for processing signals of danger. This disjunction was most apparent in patients with a profile of paranoia, coupled with poor social function and insight. Heightened autonomic sensitivity to signals of fear, threat or contamination, without effective neural mechanisms for appraisal, may underlie paranoid delusions which concern threat and contamination, and associated social and interpersonal difficulties.  相似文献   
995.
BACKGROUND: The aim of this study was to assess the correlation of overall survival with tumor location (lobar vs. deep grey matter) and with other clinical and imaging variables in a cohort of patients with high grade gliomas. METHODS: Adult patients with newly diagnosed supratentorial WHO grade 3 and 4 gliomas were evaluated. Clinical data included demographics, symptoms at presentation, treatment variables, and overall survival. Radiological data included tumor side, site (deep vs. lobar) and size, extent of peritumoral edema, and presence of midline shift. Biostatistics were carried out using log rank tests and univariate and multivariate Cox regression models. RESULTS: A total of 121 patients were investigated, 23 (19.0%) with WHO grade 3 and 98 (81.0%) with WHO grade 4 gliomas. Tumors had lobar location in 96 cases (79.3%) and deep grey matter location in 25 cases (20.7%). Median survival time for all patients was 26 weeks (IQR: 14-53). Patients with deep tumors survived significantly longer than those with lobar gliomas (log rank test, p=0.0083). Extensive brain edema significantly shortened survival (log rank test, p=0.0003). Presence of midline shift (>1 cm) was a statistically significant risk factor for shorter survival (log rank test, p<0.0001). The univariate Cox regression model demonstrated statistical significance for the variables age, side, site and size of tumor, presence of extensive edema, and presence of mass effect (>1 cm). In the multivariate Cox models, tumor grade, site and size showed statistical significance. CONCLUSIONS: This study suggests that patients with deep grey matter gliomas may survive significantly longer after the initial diagnosis than those with tumors in a lobar location. This is a potentially novel finding, which may corroborate the theory of differential invasion of glioma cells in different microenvironments of the brain, but remains to be confirmed in future prospective studies.  相似文献   
996.
997.
Nemaline rod myopathy (NM) is a rare form of congenital myopathy characterized by slowly progressive or nonprogressive muscle weakness and pathognomonic rod-like structures within the muscle fibers. To the best of our knowledge, this is first documentation of the clinicopathological features of this rare entity from India. All cases of NM diagnosed in our laboratory were retrieved. Clinical and pathological features were reviewed. During a period of 1.5 years (Jan 2004 to June 2005), we received 750 muscle biopsies for various reasons. Of which, 15 were diagnosed as congenital myopathies and four as nemaline rod myopathies. Thus, NM comprises 0.53% of all muscle diseases and 22.6% of all congenital myopathies. All of them presented in childhood (first five years of life) with generalized hypotonia, feeding problems, repeated respiratory infections and muscle weakness. Both males and females were equally affected. The CPK levels were normal and EMG was myopathic. Microscopic examination revealed minimal changes but characteristic red-colored material was seen on modified Gomori trichrome staining which was immunopositive to alpha actinin. Ultrastructural examination confirmed this material to be nemaline rods. NM, although a rare form of congenital myopathies, should be suspected in children who present with generalized hypotonia, repeated chest infections and slowly progressive muscle weakness. This report highlights the importance of histochemistry and ultrastructural examination in the diagnosis of this entity, in the absence of the availability of methodology for genetic studies.  相似文献   
998.
999.
The central nervous system activity of the petroleum ether extract of Amorphophallus paeoniifolius tuber was examined in mice, fed normal as well as healthy conditions. The petroleum ether extract of Amorphophallus paeoniifolius tuber at the doses of 100, 300 and 1000 mg/kg showed significant central nervous system activity in mice.  相似文献   
1000.

Background

Ketamine has previously been shown to induce delusion-like or referential beliefs, both acutely in healthy volunteers and naturalistically among nonintoxicated users of the drug. Delusions are theoretically underpinned by increased superstitious conditioning or the erroneous reinforcement of random events.

Materials and methods

Using a novel and objectively measured superstitious conditioning task, experiment 1 assessed healthy volunteers before and during placebo (n?=?16), low-dose (n?=?15), and high-dose ketamine (n?=?16) under randomized and double-blind conditions. Experiment 2 used the same task to compare ketamine users (n?=?18), polydrug controls (n?=?19), and nondrug-using controls (n?=?17).

Results

In experiment 1, ketamine produced dose-dependent psychotomimetic effects but did not cause changes in superstitious conditioning. Experiment 2 found increased levels of superstitious conditioning among ketamine users compared to polydrug and nondrug-using controls, respectively, as evidenced by both objective task responses and subjective beliefs following the task.

Conclusions

Results indicate that chronic but not acute exposure to ketamine may increase the propensity to adopt superstitious conditioning. These findings are discussed in terms of acute and chronic ketamine models of delusion-like belief formation in schizophrenia.  相似文献   
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