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1.
Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
2.
Abstract Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th). aged 18-65 years, mean 35 ± 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly asigned to use the 0.12% ChD mouth wash and 6i the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner κ scores of 0.78–0.85 (mean 0.81) for the plaque index (PlI), and of 0.73–0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained κ scores of 0.51–0.90 for PII and of 0.73–1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth piaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54–0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2× the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation fay 28% and gingival inflammation by 25% over a 12–week period, that it is feasible for a group of gdps to maintain high levels of inter–examiner consistency in the use of PlI and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth.  相似文献   
3.
Frequency of symptoms of depression and selected health-related practices and events were measured in a sample of 219 high school students. Students reported numerous symptoms of depression. Relative proportions of boys and girls reporting symptoms of depression were not significantly different. However, girls reported experiencing more severe depression than their male counterparts. Depression correlated significantly with several of the 22 health practices and states of affect examined. Both the determinants and manifestations of depression in adolescent cohorts require in-depth investigation. Possible implications for school health personnel are discussed.  相似文献   
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Abstrakt Vergibt ein behandelnder Arzt eine Laboruntersuchung an einen externen Laborarzt, kommt entweder direkt ein Vertragsverh?ltnis zwischen dem Laborarzt und dem Patienten zustande oder der Patient haftet dem Laborarzt aus den Grunds?tzen der Gesch?ftsführung ohne Auftrag.  相似文献   
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7.
Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
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8.
Routine clinical pharmacokinetic data collected prospectively from pediatric patients receiving theophylline were analyzed using the NONMEM (nonlinear mixed effects model) digital computer program. A total of 314 measured serum theophylline concentrations (STCs) were obtained from 84 hospitalized patients ranging in age from 4 months to 15.2 years with the majority of patients between the ages of 1 and 8 years. Fifty-six percent were male. The race/ethnicity distribution was 71.4% Latin, 15.5% black, 11.9% Caucasian, and 1.2% (one subject) Pakistani. Of the total number of observed STCs, 16.2% reflected some degree of outpatient dosing. The pharmacokinetic model used was a one-compartment open model with either zero-order or first-order absorption and first-order elimination. Age was the most important determinant of theophylline clearance (Cl);weight was inferior to age and did not statistically improve the model (p>0.005when combined with age. Total Clincreased by 10%/year over the age range of 1 to 15 years of age. Black race and male gender were associated with higher Clvalues: for a given age, Clwas 34% higher for blacks than the reference population composed of the remaining patients, and Clfor males was 25% higher than that for females. The volume of distribution (Vdfor the population was estimated to be 0.62 L/kg. The interindividual variability in Cland Vdexpressed as coefficients of variation were 19 and 28%, respectively. The residual intraindividual error variance corresponded to a standard deviation of 2.8 g/ml. The STCs that represented some degree of outpatient dosing were 21 % lower than those reflecting only inpatient dosing. Alternate models that include weight as a determinant of theophylline clearance are also provided. The NONMEM method of determining population pharmacokinetics is well suited to the pediatric population since it does not require a large number of STCs per patient. In this study a mean of only 3.7 STCs per patient were utilized to provide information which should prove useful in the design and adjustment of theophylline dosage regimens in children.  相似文献   
9.
The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA.  相似文献   
10.
One hundred and forty-four Fischer 344 rats and 144 B6C3F1 mice (72/sex/species) were fed either a control diet or a diet containing 300, 600, 1200, 2400 or 3600 ppm sulfamethazine for 90 days. They were then necropsied and tissue specimens were evaluated for pathological changes by light and transmission electron microscopy. No gross or light microscopic lesions related to sulfamethazine administration were evident in the mice. Thyroid gland enlargement was evident at necropsy in one half of the rats (12 of 24) which received the 3600 ppm level of sulfamethazine and in 1 of 24 rats fed the 2400 ppm level. By light microscopy, thyroid gland hyperplasia was evident in rats which received all 5 dose levels of the compound, but this change was more pronounced and more frequent in those animals administered the higher concentrations. This thyroid hyperplasia was observed in rats of both sexes, but with greater incidence in males than in females, among the groups receiving the lower concentrations of compound. Ultrastructural changes included markedly dilated rough endoplasmic reticulum, altered microvilli, and diminished colloid droplets involving the thyroid follicular cells and compartmentalization of colloid within the follicular lumina.  相似文献   
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