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61.
The correlation between somatosensory evoked potentials (SEPs) and sensory perception was studied in 110 patients with traumatic chronic spinal cord lesions. Perception thresholds over the legs for light touch, vibratory sensibility, temperature and thermal pain were tested together with recordings of tibial and peroneal SEPs. Tibial nerve SEPs correlated better with sensory perception than peroneal nerve SEPs. Normal tibial nerve SEPs were not present with absent or trace vibratory sensibility and vice versa. However, we found many exceptions to the correlation between temperature and pain perception and SEPs. Light touch, vibratory sensibility, and SEPs were highly correlated between each other, while temperature and pain perception correlated poorly to these other modalities. This represents an evident segregation of touch perception, vibratory sensibility and SEPs, which are thought to share dorsal columns as a common ascending pathway, and temperature and pain perception known to be related to the spinothalamic system.  相似文献   
62.
Machine learning techniques that combine multiple classifiers are introduced for classifying adult attention deficit hyperactivity disorder (ADHD) subtypes based on power spectra of EEG measurements. The analyzed sample includes 117 adults (67 ADHD, 50 controls). The measurements are taken for four different conditions: two resting conditions (eyes open and eyes closed) and two neuropsychological tasks (visual continuous performance test and emotional continuous performance test). We divide the sample into four data sets, one for each condition. Each data set is used for training of four different support vector machine classifiers, while the output of classifiers is combined using logical expression derived from the Karnaugh map. The results show that this approach improves the discrimination between ADHD and control groups, as well as between ADHD subtypes.  相似文献   
63.
BACKGROUND: Hemodialysis (HD) patients are at increased risk for arterial intimal (AIC) and medial calcification (AMC). METHODS: In a cross-sectional study on 153 HD patients we evaluated the presence of AIC and AMC using plain radiography of the pelvis and the presence of atherosclerotic lesions using high-resolution B-mode ultrasonography of the common carotid arteries (CCA). RESULTS: The radiography of the pelvis confirmed the frequent presence of AIC (35.3%) and AMC (35.9%) in our HD patients. Arterial calcification was absent (non calcified-NC) in a minority of patients (28.8%). Patients with AIC had significantly higher prevalence of atherosclerotic plaques on CCA (78.6%) compared with both other groups and a higher number of documented atherosclerotic complications, such as cardiovascular (85.2%), cerebrovascular (33.3%) and peripheral arterial disease (38.9%) in comparison with the NC patients. According to the 1-year calculated data from patient records, there were no significant differences in the specific HD risks, such as the dose of prescribed calcium carbonate and vitamin D3, serum levels of calcium, phosphate, calcium-phosphate product and intact parathyroid hormone. All four bone metabolism markers within the range proposed by K/DOQI guidelines were achieved in 9.3%, 14.5% and 20.4% in the AIC, AMC and NC group, respectively. CONCLUSIONS: Patients with AIC and AMC are frequently found in the HD population. Screening for arterial calcifications in chronic kidney disease patients is suggested even in the early pre-dialysis period. The highest proportion of patients within the guidelines proposed range for bone and mineral metabolism markers was observed in the NC group. A longer period of data analysis is required in order to evaluate the possible role of some traditional and HD-specific risk factors for the development of arterial calcifications. The achievement of the K/DOQI guidelines is an important issue in the prevention of those conditions.  相似文献   
64.
Novel Pd(II) complex with N‐heteroaromatic Schiff base ligand, derived from 8‐quinolinecarboxaldehyde (q8a) and ethyl hydrazinoacetate (haOEt), was synthesized and characterized by analytical and spectroscopy methods. The structure of novel complex, as well as structures of its quinoline and pyridine analogues, was optimized by density functional theory calculations, and theoretical data show good agreement with experimental results. A cytotoxic action of the complexes was evaluated on cultures of human promyelocytic leukemia (HL‐60), human glioma (U251), rat glioma (C6), and mouse fibrosarcoma (L929) cell lines. Among investigated compounds, only complexes with quinoline‐based ligands reduce the cell numbers in a dose‐dependent manner in investigated cell lines. The observed cytotoxic effect of two isomeric quinoline‐based complexes is predominantly mediated through the induction of apoptotic cell death in HL‐60 cell line. The cytotoxicity of most efficient novel Pd(II) complex is comparable to the activity of cisplatin, in all cell lines investigated.  相似文献   
65.
Recent studies have suggested that both high- and low-frequency repetitive transcranial magnetic stimulation (rTMS) have antidepressant effects in patients with major depression. We conducted an open study to assess the effects of slow rTMS on mood changes in patients with depression associated with Parkinson's disease (PD). Ten depressed patients with PD (four with major depression and six with dysthymia) received daily sessions of rTMS (frequency, 0.5 Hz; pulse duration, 0.1 msec; field intensity, 10% above the motor threshold) over both prefrontal regions (a total of 100 stimuli per prefrontal region daily) over 10 consecutive days. This treatment resulted in a moderate but significant decrease in scores of the Hamilton Depression Rating Scale (33-37%) and the Beck Depression Inventory (24-34%), which persisted 20 days after finishing the stimulation. In parallel, we observed mild improvement (18-20%) of motor symptoms. No significant adverse effects were reported. These preliminary results suggest the therapeutic potential of daily prefrontal low-frequency rTMS (0.5 Hz) in depression associated with PD.  相似文献   
66.
Pregnancy is a well-recognised risk factor in precipitating obsessive-compulsive disorder. We present and discuss a case with the onset of obsessive-compulsive disorder in the fourth month of gestation, which fully recovered two weeks after delivery. The phenomenology of the observed disorder was similar to earlier reports of obsessive-compulsive disorder in pregnancy, i.e. the obsessions and compulsions were predominantly related to the concern of contaminating the foetus resulting in washing compulsions. Despite the initial success with anti-obsessional drugs, the patient stopped the medication in the last month of gestation. Nevertheless, she fully recovered two weeks after the delivery without any psychiatric intervention. There were no obsessive-compulsive symptoms at one-year follow up. The possible mechanisms involved in the aetiology of this case, and future research directions in understanding the role of pregnancy in OCD are discussed.  相似文献   
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69.
BACKGROUND: Short-term refrigeration of platelets (PLTs) in the absence of plasma results in their rapid clearance after transfusion. Blocking beta-N-acetylglucosamine (beta-GlcNAc) residues of glycoprotein Ibalpha (GPIbalpha) with galactose prevents binding of refrigerated human and mouse PLTs to macrophages and prolongs the circulation times of refrigerated mouse PLTs. PLT-associated galactosyltransferase efficiently galactosylates chilled PLTs in the presence of its substrate UDP-galactose is added to PLT-rich plasma. STUDY DESIGN AND METHODS: To characterize the hemostatic function of refrigerated and galactosylated human PLTs processed in the blood bank, PLT aggregation was studied in vitro under static and flow conditions and expression of integrin beta3 (CD61), CD62P (P-selectin), GPIbalpha (CD42b), annexin V binding, and integrin alphaIIbeta3 activation with flow cytometry. Affinity of macrophages for galactosylated refrigerated PLTs was evaluated with THP-1 cells, which recognize and phagocytize refrigerated PLTs. RESULTS: PLTs refrigerated and galactosylated for 14 days 1) maintained their ability to aggregate when exposed to agonists in a standard aggregometry assay, 2) showed less pronounced changes in surface expression of GPIbalpha compared with room temperature (RT)-stored PLTs, 3) increased P-selectin expression, and 4) were poorly phagocytized by differentiated THP-1 cells in vitro. In addition, it is shown that refrigeration of PLTs does not affect their adhesive properties under in vitro flow conditions. CONCLUSION: It is shown that refrigerated human PLTs retain in vitro function better than RT PLTs during storage and demonstrate that galactosylation prevents recognition of stored refrigerated PLTs by macrophages in vitro.  相似文献   
70.
BACKGROUND: The primary aim of this study was to compare the efficacy of combined spinal-epidural (CSE) analgesia vs. intermittent bolus epidural analgesia (EA) for pain relief after major abdominal surgery. The secondary aim was to assess the effects of fentanyl addition to subarachnoid morphine and bupivacaine. METHODS: This was a prospective, randomised, double-blind trial; 160 patients scheduled for major abdominal surgery enrolled. All patients had a thoracic epidural catheter for administration of intra-operative and postoperative analgesia. Patients were assigned to one of four groups: (i) subarachnoid morphine, bupivacaine and fentanyl (MBF group); (ii) morphine and bupivacaine (MB group); (iii) morphine (M group) and (iv) normal saline (EA group). Use of additional intravenous (i.v.) fentanyl and epidural bupivacaine was recorded to measure the need for supplemental intra-operative analgesia. Pain at rest, with movement, and with cough (measured with a visual analogue scale), additional analgesia requests, and side effects were recorded over 72 h postoperatively. RESULTS: Compared with the EA group, the MBF group had significantly reduced pain with cough and lower analgesia requirements during the first 24 h (p<0.001) and after EA discontinuation (p=0.041). The MBF group required less intra-operative epidural bupivacaine compared with all other groups (p<0.001), and less intra-operative i.v. fentanyl compared with group M (p<0.001). CONCLUSIONS: Combined spinal-epidural improved intra-operative analgesia and reduced pain with cough in the immediate postoperative period. The addition of fentanyl to subarachnoid morphine and bupivacaine decreased the need for additional i.v. fentanyl and epidural bupivacaine analgesia.  相似文献   
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