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1.
Event-related potentials (ERPs) to visual stimuli were recorded from the scalp of eight adult humans performing a task in which they counted vowels from a heard story. In the oddball condition, a repeated (standard) light bar of 50 ms in duration was rarely (P = 0.1) replaced by a (deviant) one differing in orientation from the standard. In the control condition, standards were simply omitted from the series and only (alone-) deviants retained. In both conditions, visual stimuli were asynchronous with auditory-task-relevant stimuli. ERPs to deviants significantly differed in amplitude from those to standards in the midline electrodes centrally, parietally and occipitally at 160-200 ms from stimulus onset. Occipitally, such a difference was absent between ERPs to alone-deviants and those to standards. The occipital differential ERPs to deviants, which thus could be found only when standards were present in the series, are discussed in the context of the mismatch negativity (MMN).  相似文献   
2.
The full-length infectious cDNA clone was constructed and sequenced from the strain DM of echovirus 9, which was recently isolated from a 6-week-old child at the clinical onset of type 1 diabetes. Parallel with the isolate DM, the full-length infectious cDNA clone of the prototype strain echovirus 9 Barty (Barty-INF), was constructed and sequenced. Genetic relationships of the sequenced echo 9 viruses to the other members of the human enterovirus type B species were studied by phylogenetic analyses. Comparison of capsid protein sequences showed that the isolate DM was closely related to both prototype strains: Hill and Barty-INF. The only exception was the inner capsid protein VP4 where serotype specificity was not evident and the isolate DM clustered with the strain Hill and the strain Barty-INF with echovirus 30 Bastianni. Likewise, the nonstructural protein coding region, P2P3, of isolate DM was more similar to strain Hill than to strain Barty-INF. However, like echovirus 9 Barty, the isolate DM contained the RGD-motif in the carboxy terminus of capsid protein VP1. By blocking experiments using an RGD-containing peptide and a polyclonal rabbit antiserum to the alpha(v)beta(3)-integrin, it was shown that this molecule works as a cellular receptor for isolate DM. By using primary human islets, it was shown that the isolate DM is capable of infecting insulin-producing beta-cells like the corresponding prototype strains did. However, only isolate DM was clearly cytolytic for beta-cells. The infectious clones that were made allow further investigations of the molecular features responsible for the diabetogenicity of the isolate DM.  相似文献   
3.
Human rhinoviruses (HRV) have been shown to be the major causative agent for mild respiratory infections, but also associated with more serious diseases, such as acute otitis media and pneumonia in children, and asthma. Despite the economical and medical importance of HRV, little is known about the circulation and genetic diversity of HRV during a given season. The aim of this study was to genetically characterize HRV strains causing acute respiratory infections in a cohort of small children during a 2 years follow-up time. Genetic relationships between 61 HRV field isolates were studied using partial genomic sequencing in the VP4/VP2 region (420 nt) and phylogenetic analysis of these sequences. Sequences from the clinical isolates clustered in the two previously known phylogenetic clades, the designated genetic group 2 (including HRV 14) being more predominant. The maximum genetic variation within group 1 was 32.3% and within group 2 it was 32.7%. Several distinct clusters could be observed, some of which were strictly seasonal, whereas some other variants were detected during several seasons. The results of this study show striking genetic diversity of the HRV strains circulating in a given community during a short time.  相似文献   
4.
Several studies have compared bone marrow (BM) and peripheral blood (PB) as stem cell sources in patients receiving allografts, but the cell doses infused have not been considered, especially for BM. Using the ALWP/EBMT registry, we retrospectively studied 881 adult patients with acute myelocytic leukemia (AML), who received a non-T-depleted allogeneic BM (n = 515) or mobilized PB (n = 366) standard transplant, in first remission (CR1), from an HLA-identical sibling, over a 5-year period from January 1994. The BM cell dose ranged from 0.17 to 29 x 10(8)/kg with a median of 2.7 x 10(8)/kg. The PB cell dose ranged from 0.02 to 77 x 10(8)/kg with a median of 9.3 x 10(8)/kg. The median dose for patients receiving BM (2.7 x 10(8)/kg) gave the greatest discrimination. In multivariate analyses, high-dose BM compared to PB was associated with lower transplant-related mortality (RR = 0.61; 95% CI, 0.39-0.98; P =.04), better leukemia-free survival (RR = 0.65; 95% CI, 0.46-0.91; P =.013), and better overall survival (RR = 0.64; 95% CI, 0.44-0.92; P =.016). The present study in patients with AML receiving allografts in first remission indicates a better outcome with BM as compared to PB, when the dose of BM infused is rich.  相似文献   
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Objectives. We sought to investigate whether functional abnormalities in coronary vasomotion exist in young adults by studying 15 men (age 31 ± 8 years [mean ± SD]) with familial hypercholesterolemia (FH) and a matched group of 20 healthy control subjects.

Background. Precursors of morphologic coronary artery disease are known to be present in adolescents and young adults with a high risk factor profile.

Methods. Myocardial blood flow was measured at the basal state and during dipyridamole-induced hyperemia using positron emission tomography and oxygen-15–labeled water.

Results. Serum total and low density lipoprotein cholesterol concentrations were higher in the patients than in the control subjects (mean ± SD): 7.7 ± 1.9 versus 5.3 ± 1.5 mmol/liter (298 ± 73 vs. 205 ± 58 mg/dl) and 6.1 ± 1.8 versus 3.5 ± 1.4 mmol/liter (236 ± 70 vs. 135 ± 54 mg/dl), respectively (both p < 0.001). The baseline myocardial blood flow was similar in the patients and control subjects: 0.92 ± 0.24 versus 0.83 ± 0.13 ml/g per min, respectively (p = 0.21). A significant increase in flow was observed in both groups after dipyridamole infusion, but the flow at maximal vasodilation was 29% lower in the patients: 3.19 ± 1.59 versus 4.49 ± 1.27 ml/g per min (p = 0.011). Consequently, coronary flow reserve (the ratio of hyperemia flow to basal flow) was 35% lower in the patients than in the control subjects: 3.5 ± 1.6 versus 5.4 ± 1.5 (p = 0.0008). Total coronary resistance during hyperemia was higher in the patients than in the control subjects: 36 ± 25 versus 21 ± 10 mm Hg/min per g per ml (p = 0.045). Coronary flow reserve was inversely associated with serum total cholesterol concentration: r = −0.43 (p = 0.009).

Conclusions. Coronary flow reserve is reduced in young men with FH, and, consequently, coronary resistance during hyperemia is increased. The results demonstrate very early impairment of coronary vasomotion in hypercholesterolemic patients.

(J Am Coll Cardiol 1996;28:1705–11)  相似文献   

8.
The purpose of the study was to examine in vivo placental transfer of metformin, its association with neonatal outcome in metformin-treated gestational diabetes (GDM) patients, and influence of metformin exposure on maternal glycemic control and weight gain. Two hundred and seventeen GDM patients were randomized to metformin or insulin in Turku University Hospital, Finland. Metformin concentrations were determined by mass spectrometry in maternal serum at 36 gestational weeks (gw) and at birth, and in umbilical cord blood. Main outcome measures were birth weight, gw at birth, umbilical artery pH and neonatal hypoglycemia, maternal weight gain, HbA1c and fructosamine concentration. Median umbilical cord/maternal serum metformin concentration ratio was 0.73. There were no differences in birth weight measured in grams or SD units (p = 0.49), or gw at birth (p always ≥0.49) between insulin- and metformin-treated patients stratified by trough metformin concentration tertiles measured at 36 gw. Rate of neonatal hypoglycemia (p = 0.92) and umbilical artery pH value (p = 0.78) was similar in insulin- and metformin-treated patients stratified by cord metformin concentration tertiles. Maternal glycemic control was similar in metformin concentration tertiles at 36 gw. Maternal weight gain was 223 g greater per week (p = 0.038) in the lowest metformin tertile compared to other tertiles combined. Maternal and fetal exposure to metformin is similar. Maternal or fetal metformin concentrations do not predict maternal glycemic control or neonatal outcome, but low maternal exposure may lead to greater maternal weight gain.  相似文献   
9.
Objective. To investigate the outcome of early rheumatoid arthritis (RA) when treated according to the “sawtooth” strategy, and to compare the results with the findings of other studies. Methods. In this prospective study, 142 patients with early RA were treated actively with slow-acting antirheumatic drugs (SAARDs) for an average of 6.2 years, and were closely monitored clinically. Several outcome measures were applied, and the results were compared with findings in previously described cohorts. Results. The mean cumulative number of SAARDs used during the study was 3.3. Treatment changes were made because of inefficacy more often than because of adverse events. The percentage of patients whose disease entered remission increased with time to 32% (45 of 142). Only 24% of the patients (34 of 142) had deterioration to Steinbrocker functional class III or IV. The “sawtooth” treatment strategy seemed to improve the outcome of the patients with early RA. Conclusion. In the majority of patients with early RA, “sawtooth” therapy remains beneficial for at least 6 years. However, in one-fourth of the patients, the disease fails to respond to this drug treatment strategy.  相似文献   
10.
Temperature‐related reflex epilepsy most often takes the form of hot water epilepsy, but very rarely, reflex epilepsy is related to cold temperature. We report a 70‐year‐old male who had seizures triggered by cold sensations in the body. Four antiepileptic drugs were taken during the drug treatment, and oxcarbazepine was the most effective at stopping the seizures. We implemented clinical seizure induction and obtained EEG data from an interictal period and two complete ictal periods. Source estimation was performed to identify and map the primary sources involved in the seizures on the cortical level. We found that β rhythm appeared on the prefrontal lobes during the whole ictal period. The low‐frequency slow δ and θ rhythms, especially the δ rhythm, appeared in the occipital lobe in the early ictal stage and propagated to the right temporal lobe in the mid‐late ictal stage. The prefrontal lobe and right temporal lobe were mainly involved in the generation and propagation of the epileptic activities. This study provides a valuable reference for clinical drug therapy and provides insights into the characteristics of the brain activities involved in cold‐induced reflex epilepsy. [Published with video sequences].  相似文献   
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