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991.
992.
Giffin KM 《General dentistry》2003,51(1):62-7; quiz 68-9
Maximum dental intercuspation (MI) is directed through sensory feedback from periodontal proprioceptors and is a neuromuscularly favored and protective mandibular position for the dentition. MI literally drives the stomatognathic system. When MI and centric relation (CR) are not in harmony, the mandible assumes adaptive reposturing in an effort to achieve as much MI as mechanically possible. This can lead to an autodestructive syndrome that damages various stomatognathic elements. Diurnal and nocturnal clenching and/or bruxism as well as other parafunctional activities mediated at different neurologic levels may complicate the problem further. Effective management of this syndrome requires establishment of harmony between CR and MI.  相似文献   
993.
A simple, broadly applicable, standardized dysphagia severity scale would be useful to standardize dysphagia evaluations, to monitor recovery and efficacy of treatment and to study the consequences of dysphagia. We developed a global Dysphagia Severity Scale (DSS) from videofluorographic swallowing studies which included subjective clinical ratings of functional swallowing. We rated laryngeal penetration/aspiration (P/A) and pharyngeal retention (PR), and then assessed methods for scoring severity of P/A and PR and for combining them in a global scale. Each method was tested by correlation with overall clinical severity ratings. The highest correlations were found by: 1) scoring P/A based on which foods were aspirated (no aspiration or penetration; penetration only; thin liquid aspiration; thick liquid, pudding, or chewed solid food aspiration; 2) scoring PR based on how much food was retained (none; minimal; moderate; severe); and 3) combining P/A and PR by taking the higher of the two scores as the final DSS rating. The final global DSS score and the clinical severity rating correlated well (r = 0.71). This proposed scale shows promise for rating global dysphagia severity.  相似文献   
994.
995.
Neonatal rats exposed to 95% oxygen (O2) for 7 days from birth had inhibited lung growth, DNA synthesis, and secondary septation. These parameters were rapidly restored by a period of recovery in air. Northern and Western blot analysis and immunohistochemistry were used to screen for the fibroblast growth factor receptor-1 (FGF-R1) and its high affinity ligand, basic fibroblast growth factor (bFGF), which could have a role in this recovery process. Expression of bFGF in the lung was significantly reduced at the end of the 7-day exposure to 95% O2 and was increased after 3 days of recovery in air. Expression of FGF-R1 was not affected by exposure to 95% O2 or recovery in air. We hypothesized that the increase in bFGF after removal from 95% O2, acting through the FGF-R1, would be critical for compensatory growth. Intraperitoneal injection of soluble truncated FGF-R1 at the onset of the recovery phase arrested compensatory lung DNA synthesis and secondary septation seen in control animals after 3 days of recovery, confirming a role for FGF-R1 in this model of compensatory neonatal lung growth.  相似文献   
996.
Hepatotoxicity of the thiazolidinediones   总被引:5,自引:0,他引:5  
Troglitazone, the first of the thiazolidinediones, caused severe hepatotoxicity including liver failure in several patients. It appears, however, that the thiazolidinediones as a class are not as hepatotoxic as troglitazone. Comparative data at comparable dates of usage indicate that pioglitazone and rosiglitazone are not significant hepatotoxins. This is further supported by experimental data that demonstrate that troglitazone, alone among the thiazolidinediones, is toxic in hepatocyte cell culture. All of the thiazolidinediones cause ALT elevations; however, ALT monitoring for hepatotoxicity does not appear to prevent serious liver disease nor reduce patient risk.  相似文献   
997.
BACKGROUND: Mortality in patients with mild to moderate chronic heart failure remains high. At present there is no easy way of identifying patients within this population at increased risk of death in the medium to long term. AIMS: To develop a prognostic index to identify outpatients with mild to moderate chronic heart failure at increased risk of death. METHODS AND RESULTS: Five hundred and fifty-three outpatients mean (S.D.) age 63(+/-10) years with symptoms of chronic heart failure (mean New York Heart Association functional class, 2.3(+/-0.5)), were recruited between December 1993 and April 1995. By April 2000, 201 patients had died. Using data from non-invasive measurements of cardiac size, electrical and autonomic function, renal function and plasma biochemistry we identified eight independent predictors of mortality (all P<0.01). To develop a prognostic index, predictors were dichotomised by group median and awarded 0 or 1 point accordingly. Serum sodium /=111 micromol/l (1 point), cardiothoracic ratio >/=0.52 (1 point), SDNN /=487 ms (1 point), QRS dispersion>/=42.7 ms (1 point), the presence of non-sustained ventricular tachycardia (1 point) and voltage criteria for left ventricular hypertrophy on 12-lead ECG (1 point). We calculated risk scores for patients by adding the points of each independent risk factor. In the low-risk group (0-3 points) mortality at 5 years was 20% and in the high-risk group (4-8 points) 53%. The area under the receiver-operator characteristic curve using dichotomised variables was 0.74 and for continuous model 0.78. CONCLUSIONS: Our prognostic index which uses eight non-invasive measurements and a straightforward additive points system, has good discrimination and stratifies outpatients with chronic heart failure into high and low risk. This index may be useful in clinical care and risk stratification.  相似文献   
998.
Depression is a well-established risk factor for cardiovascular disease-related morbidity and mortality. It is common to screen for depression in patients undergoing coronary revascularization prior to revascularization; however, the validity of this assessment is unclear as some patients may experience transient, reactive depression rather than persistent depression. The authors evaluated whether an initial or 1-month postprocedure screen was optimal for identifying consistently depressed patients. Depression at 1-month postprocedure was a stronger predictor of depression at months 2 to 6 than baseline depression. After adjusting potential confounding variables, there was a much stronger relationship between 1-month and 6-month depression status (OR = 28.7 if depressed at 1 month, p < .001) than between baseline and 6-month depression status (OR = 6.5 if depressed at baseline, p < .001). Screening for depression at the time of revascularization is not as predictive of depression at 6 months as it is 1 month postprocedure.  相似文献   
999.
BACKGROUND: Sleep complaints are common in patients with major depressive disorder (MDD). Both MDD and antidepressant drugs characteristically alter objective sleep measures. This study compares the effects of mirtazapine and fluoxetine on sleep continuity measures in DSM-IV MDD patients with insomnia. METHOD: Patients (N = 19) received initial baseline polysomnography evaluations over 2 consecutive nights. Subjects were randomly assigned to either fluoxetine (20-40 mg/day) or mirtazapine (15-45 mg/day) treatment for an 8-week, double-blind, double-dummy treatment trial. Single-night polysomnograms were conducted at weeks 1, 2, and 8, with depression ratings assessed at baseline and weeks 1, 2, 3, 4, 6, and 8. Statistical analysis was performed by repeated-measures analysis of variance followed by Dunnet's post hoc analyses. RESULTS: Patients receiving mirtazapine (N = 8) had significant improvement in objective sleep physiology measures at 8 weeks. Improvements in sleep latency, sleep efficiency, and wake after sleep onset were significant after only 2 weeks of mirtazapine treatment. No significant changes in sleep continuity measures were observed in the fluoxetine group (N = 11). Both groups improved clinically in mood and subjective sleep measures from baseline, with no differences between groups. CONCLUSION: These data demonstrate the differential effects of mirtazapine and fluoxetine, with significant improvement in favor of mirtazapine, on objective sleep parameters in MDD patients with insomnia.  相似文献   
1000.
The objectives of this study were (1). to examine the changes in regional cerebral blood flow (rCBF) during Wisconsin Card Sorting Test (WCST) performance in two different eye-tracking groups; (2). to explore the relationship between eye-tracking movement and rCBF at rest; and (3). to estimate the association between WCST performance and rCBF in patients with schizophrenia. A total of 17 patients with schizophrenia were recruited. SPECT with Tc-99m HMPAO (Tc-99m hexamethylpropyleneamine oxime) was carried out while patients were performing the WCST and resting. Brodmann area 9 of the prefrontal cortex, a part of the dorsal lateral prefrontal cortex (DLPFC), was less activated during performance of the WCST in poor trackers (relative to good trackers). The eye pursuit tracking error measure in schizophrenic patients was negatively associated with decreases in rCBF in the middle temporal area, superior parietal lobule, thalami, and caudate nuclei. The rCBF increased significantly in the superior temporal gyri, inferior parietal lobe, and some frontal regions during WCST performance; however, this was not the case in the DLPFC. Additionally, significant correlations were found between WCST scores and rCBF during WCST performance in the prefrontal lobes, and in thalamic and cerebellar regions. Our findings suggest that the rCBF changes during WCST performance may be distinctive in different eye-tracking groups. Our results confirm the hypothesis that the middle temporal area, superior parietal lobule, thalami, and caudate nuclei-mainly parts of the oculomotor circuit-are involved in eye pursuit tracking. Surprisingly, no significant association was found in the frontal eye field. Although the frontal lobe plays a significant role in WCST performance, our findings demonstrate that WCST performance is widely involved with other regions in patients with schizophrenia.  相似文献   
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