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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.
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   
4.
5.
OBJECTIVE: Caregivers of young children frequently measure doses of liquid medications incorrectly. Use of nonstandardized dosing instruments and lack of knowledge that dosing is weight-based contribute to dosing errors. We sought to assess whether low caregiver health literacy was associated with these outcomes. METHODS: This was a cross-sectional analysis of caregivers presenting to an urban pediatric emergency room. Dependent variables were caregiver reported use of nonstandardized dosing tools and knowledge of weight-based dosing. The independent variable was caregiver health literacy (Test of Functional Health Literacy in Adults [TOFHLA]). RESULTS: Two hundred ninety-two caregivers were assessed: 23.3% reported use of nonstandardized liquid dosing instruments, and 67.8% were unaware of weight-based dosing. Caregivers who were unaware of weight-based dosing were more likely to use nonstandardized dosing tools (28.3% vs 12.8%; P = .003). In unadjusted analyses, overall health literacy, reading comprehension, and numeracy were all associated with both dependent variables. In analyses adjusting for child age, health care experiences, and caregiver acculturation and education, inadequate/marginal overall health literacy was associated with lack of knowledge of weight-based dosing (adjusted odds ratio [AOR] 2.3; P = .03), whereas lower reading comprehension was associated with both lack of knowledge (AOR 2.0; P = .03) and reported use of nonstandardized instrument (AOR 2.4; P = .007). CONCLUSIONS: Low health literacy, in particular reading comprehension, was associated with reported use of nonstandardized dosing instruments and lack of knowledge regarding weight-based dosing. Both caregiver health literacy and sociodemographic factors should be considered in the design of interventions to prevent medication administration errors.  相似文献   
6.
Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
  相似文献   
7.
1. The radioligand [125I]-endothelin was used to map receptors for endothelin in rat adrenal gland using in vitro autoradiography and computerized densitometry. 2. In the adrenal, a high density of binding was found in the adrenal medulla (binding affinity constant 0.18 +/- 0.11 X 10(9)M-1) and zona glomerulosa (binding affinity constant 0.18 +/- 0.07 X 10(9)M-1). Binding was low to undetectable in the zona fasciculata and zona reticularis. Unrelated peptides did not displace endothelin. 3. These results provide evidence of endothelin receptor distribution in adrenal gland and suggest that endothelin might exert multiple actions in the adrenal gland on catecholamine and aldosterone biosynthesis and secretion.  相似文献   
8.
PURPOSE: Malignancy can be associated with high levels of catabolic products. We performed a two-part study. Part 1 measured levels of uric acid and xanthine in the aqueous humor of eyes with malignant and nonmalignant diagnoses. Part 2 measured the levels of uric acid in tears of retinoblastoma patients. If compounds in high concentrations inside the eye could be detected outside the eye, via diffusion, in high concentrations in the tears, then a tear screening test for retinoblastoma could be developed. METHODS: High-performance liquid chromatography measured levels of uric acid and xanthine in aqueous humor samples of patients with retinoblastoma, melanoma, Coats' disease, adult cataract, and congenital cataract. Tear sampling was performed on patients with retinoblastoma and on normal eyes, and samples were assayed for uric acid. RESULTS: Part 1--Uric acid was elevated in the aqueous humor of eyes with retinoblastoma, melanoma, and Coats' disease compared with eyes with cataracts. Xanthine was elevated in retinoblastoma and Coats' disease and was lower in adult and congenital cataracts and melanoma. Part 2-No significant difference was found in the concentrations of uric acid in the tears of patients with retinoblastoma and those of normal patients. CONCLUSIONS: High levels of uric acid and xanthine present in the aqueous humor of patients with malignancy are consistent with the destructive nature of these conditions. Although uric acid was not elevated in the tears of retinoblastoma patients, continued investigation into substances that might be measurably different in the tears may yield a useful screening test in the future.  相似文献   
9.
The pathological features of 13 cases with juxtaposition of the atrial appendages in the autopsy files of The Johns Hopkins Hospital were studied. The anomaly occurs most frequently in association with transposition of the great vessels, ventricular septal defect, patent foramen ovale, and obstructive lesions of the tricuspid and pulmonic valves. The malformation complex of tricuspid atresia, atrial and ventricular septal communication, and the transposition of the great vessels seems particularly common with juxtaposition of the atrial appendage. A recent case showed a small accessory right atrial appendage lying in juxtaposition to the left atrial appendage. In addition, a normally situated right atrial appendages in addition to well-formed accessory appendages lying in juxtaposition to the left atrial appendages. It seems that juxtaposition of the atrial appendages should be reinterpreted as an accessory appendage or atrial diverticulum.  相似文献   
10.
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   
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