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991.
992.
Frequently, correct evaluation of space-occupying lesions in the tongue is not possible with clinical methods only. In an attempt to assess the value of sonography in the detection of tongue lesions, we used submental sonography to examine 62 patients with suspicious palpatory findings upon physical examination of the tongue. Ultrasound detected 45 out of 47 tumours that were eventually confirmed either by surgery or by biopsy. Inadequate technique was the only factor that affected the detection rate. Sonography appears to be a reasonable guide in determining size and site of a tumour of the tongue. Thus, more precision in therapy planning may be achieved.  相似文献   
993.
BACKGROUND: Atypical antipsychotics have been assessed for normalization effects on deficient sensory gating as indexed by prepulse inhibition (PPI) in schizophrenics with generally positive, although somewhat conflicting, results. METHODS: We tested the acute effect of clozapine on startle, PPI, and attention, working memory, and executive functioning in 28 healthy male volunteers with low versus high PPI levels using a placebo-controlled within-subject design. RESULTS: Clozapine significantly increased PPI levels obtained at short lead intervals of 60 and 120 msec in subjects with low PPI performance but showed no effect in subjects with high PPI. Clozapine also caused a mild cognitive impairment on attention and pattern recognition memory tests. No correlations between cognitive measures and PPI performance were found. Moreover, low and high PPI performers were shown to exhibit stable levels of PPI across three separate nondrug testing days. CONCLUSIONS: Clozapine increases sensorimotor gating in healthy subjects with low but not high PPI levels in a manner comparable to that seen in clozapine-treated schizophrenia patients. Healthy subjects with low PPI level in combination with genetic studies may provide a translational model to elucidate the neuronal basis of PPI deficits and to test the efficacy of novel antipsychotic medication.  相似文献   
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Histamine plays an important role in the allergic inflammation. Histamin N-Methyltransferase (HNMT) catalyses the major pathway of histamine metabolism in the human lung. A common functional single nucleotide polymorphism (SNP) within the HNMT gene (C314T) was recently related to asthma. We tested this SNP for associations with asthma and asthma associated traits in two German pediatric populations (1. MAS-cohort, n=888, 85 children with asthma; 2. asthmatic children from Freiburg, n=176). Non-asthmatic (n=515) and non-atopic (n=211) children from the MAS-cohort were used as controls. For genotyping melting curve analyses (Light Cycler System) were applied. In contrast to a previous study, no association of the HNMT 314T allele with asthma, bronchial hyperresponsiveness (BHR) or other asthma related phenotypes could be observed in either study population. We conclude that this SNP might not play a major role in the pathogenesis of asthma or BHR in German children.  相似文献   
998.
Determinants of B-type natriuretic peptide (BNP) plasma levels in the chronic phase after heart transplantation remain unclear. BNP was measured in 105 stable long-term heart transplant recipients with normal left ventricular function by echocardiography and correlated with clinical, demographic and hemodynamic parameters. Multivariate analysis revealed a significant correlation of BNP with female recipient gender (P = 0.006), time post-transplant (P =0.006), donor age (P = 0.007), angiographic signs of transplant vasculopathy (TVP) (P = 0.03), serum creatinine level (P = 0.04), and a strong trend for diastolic dysfunction (P = 0.09). Donor gender, recipient age, cyclosporin A blood levels, rejection history, and pulmonary artery pressure had no independent effect on BNP. BNP after heart transplantation appears to be influenced both by established general determinants (female gender, renal function) and transplant-specific determinants such as time post-transplant, donor age and potentially also TVP. In order to determine the value of BNP as a potential surrogate marker of TVP serial intraindividual measurements appear appropriate.  相似文献   
999.
The coronary artery calcium (CAC) score is a readily and widely available tool for the noninvasive diagnosis of atherosclerotic coronary artery disease (CAD). The aim of this study was to investigate the added value of the CAC score as an adjunct to gated SPECT for the assessment of CAD in an intermediate-risk population. METHODS: Seventy-seven prospectively recruited patients with intermediate risk (as determined by the Framingham Heart Study 10-y CAD risk score) and referred for coronary angiography because of suspected CAD underwent stress (99m)Tc-tetrofosmin SPECT myocardial perfusion imaging (MPI) and CT CAC scoring within 2 wk before coronary angiography. The sensitivity and specificity of SPECT alone and of the combination of the 2 methods (SPECT plus CAC score) in demonstrating significant CAD (>/=50% stenosis on coronary angiography) were compared. RESULTS: Forty-two (55%) of the 77 patients had CAD on coronary angiography, and 35 (45%) had abnormal SPECT results. The CAC score was significantly higher in subjects with perfusion abnormalities than in those who had normal SPECT results (889 +/- 836 [mean +/- SD] vs. 286 +/- 335; P < 0.0001). Similarly, with rising CAC scores, a larger percentage of patients had CAD. Receiver-operating-characteristic analysis showed that a CAC score of greater than or equal to 709 was the optimal cutoff for detecting CAD missed by SPECT. SPECT alone had a sensitivity and a specificity for the detection of significant CAD of 76% and 91%, respectively. Combining SPECT with the CAC score (at a cutoff of 709) improved the sensitivity of SPECT (from 76% to 86%) for the detection of CAD, in association with a nonsignificant decrease in specificity (from 91% to 86%). CONCLUSION: The CAC score may offer incremental diagnostic information over SPECT data for identifying patients with significant CAD and negative MPI results.  相似文献   
1000.
OBJECTIVES: To compare the value of three-dimensional placental volume at 12 weeks and uterine artery Doppler at 22 weeks for predicting pregnancy-induced hypertension (PIH), pre-eclampsia and fetal growth restriction in a low-risk population. METHODS: Over a 20-month period we calculated the placental quotient (PQ = placental volume/crown-rump length) at 11-13 weeks' gestation in all women with singleton pregnancies who booked for delivery in our hospital. At 22 weeks, in the same population, we calculated the mean pulsatility index (PI) of both uterine arteries and the presence of an early diastolic notch was noted. Logistic regression models, the PQ and Doppler parameters were used to compare the two screening methods for subgroups of pregnancy outcome. RESULTS: Complete outcome data were obtained in 2489 consecutive singleton pregnancies. Logistic regression models for the detection of pre-eclampsia had a sensitivity of 38.5% (PQ) vs. 44.8% (Doppler); for the detection of small-for-gestational age (SGA) the sensitivity was 27.1% (PQ) vs. 28.1% (Doppler) at a specificity of 90%. Taking a PQ of or= 90th centile and a bilateral notch, the sensitivity for detection of SGA was 25.0%, 20.2% and 22.0%, respectively; for PIH it was 9.5%, 4.8% and 4.8%; for pre-eclampsia without SGA it was 20.0%, 28%, 12%; for PIH/pre-eclampsia with SGA it was 30.8%, 46.1% and 69.2%. In the group with the most severe complications, in which delivery took place before 34 weeks, the sensitivity was 50.0%, 50.0% and 38.9%, respectively. CONCLUSIONS: PQ at 12 weeks and uterine artery Doppler at 22 weeks have similar sensitivities for predicting pre-eclampsia and fetal growth restriction, although uterine artery Doppler is marginally more sensitive for the prediction of pre-eclampsia. While both methods are insufficient for screening in a low-risk population, the PQ method has the potential advantage of being performed in the first trimester.  相似文献   
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