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51.
BACKGROUND AND OBJECTIVES: To validate accuracy and reproducibility of the Perkins tonometer, pneumatonometer, and Tono-Pen XL (Medtronic Solan, Jacksonville, FL) in estimating intraocular pressure (IOP) in rabbits. MATERIALS AND METHODS: IOP was increased from 5 to 50 mm Hg in 5-mm increments. Measurements were compared to readings of two digital manometers simultaneously measuring real IOP in the anterior chamber and vitreous cavity. Interobserver accuracy was evaluated using 4 eyes with the Perkins tonometer. RESULTS: The Perkins tonometer and Tono-Pen XL underestimated IOP and were more accurate at pressures less than 30 mm Hg. No statistically significant difference was found between real IOP and Tono-Pen XL readings. The pneumatonometer overestimated pressures in the low ranges but was accurate at pressures greater than 40 mm Hg. The Tono-Pen XL had more variability than the Perkins tonometer and pneumatonometer at high IOP. CONCLUSIONS: None of the tonometers are accurate or reproducible in estimating IOP in rabbits over the tested range. Pneumatonometry, although not very accurate, has the advantage of having acceptable variability.  相似文献   
52.
Dotterud LK, Falk ES. Contact allergy in relation to hand eczema and atopic diseases in north Norwegian schoolchildren. Acta Psediatr 1995;84:402–6. Stockholm. ISSN 0803–5253
Patch testing was carried out in 424 schoolchildren (223M, 201F), aged 7–12 years, in northern Norway. In 99 (23.3%) of these children, one or more allergic patch test reactions were demonstrated; 30 children reacted to two and 6 to three or more substances; 53 irritant reactions were recorded in 33 (7.8%) of those tested. From a total of 144 positive tests, the most common allergen was nickel (14.9%), followed by cobalt (5.7%), kathon CG (5.2%), lanolin (1.7%) and neomycin (1.4%). Both allergic and irritant reactions were found twice as frequently in girls as in boys. Positive patch tests were significantly more frequent in atopic (28.8%) than in non–atopic (17.9%) children, being most pronounced in atopic girls (37.4%). Hand eczema was reported to have occurred or to be present in 6.5% of cases. Twenty–nine of 36 children reporting hand eczema participated in the clinical examination. Altogether 15 (3.5%) children had hand eczema at the time of the clinical examination but 12 of these children had no previous history of hand eczema. In 14 of these 15 subjects, the eczema was localized to the back of the hands, with 13 having atopic dermatitis. In 4 of these 15 children, an allergic patch test reaction was found; however, in only 2 of these 4 was the test considered to be clinically relevant for the diagnosis allergic hand eczema. In conclusion, irritant hand eczema may occur in early childhood and is most prevalent in children with atopic dermatitis  相似文献   
53.
Technetium-99m hexakis-2-methoxy-isobutyl-isonitrile(99mTc sestamibi) has been used for myocardial perfusion imaging in the evaluation of coronary artery disease (CAD) since 1990. The experience of its use in an Asian population with and without previous myocardial infarction (Ml), diabetes mellitus (DM), hypertension (HPT) and collateral circulation (COL) is reported. One hundred and thirty-nine patients who underwent treadmill exercise testing with 99mTc sestamibi single photon emission computed tomography (SPECT) and coronary angiogram were studied. The overall sensitivity for the detection of CAD was 91.0% and specificity was 64.7%. For patients without previous myocardial infarction, the sensitivity was 83.8% and specificity was 83.3%. Patients with COL had a higher sensitivity while those with HPT had a lower specificity. Sensitivity was higher in patients with multi-vessel disease (MVD) than single vessel disease (SVD). The overall detection for individual artery stenosis was 74.1% with a specificity of 73.1 %. Amongst the three major coronary arteries, sensitivity was highest for the right coronary artery and specificity was highest for the left circumflex artery. Specificity was higher in patients without MI or COL. We found that the agreement between 99mTc sestamibi SPECT and coronary angiogram for the extent of CAD was only 52.5%. The concordance rate was higher for patients with MVD than SVD. It is concluded that 99mTc sestamibi SPECT is a sensitive and specific test for the detection of CAD and localization of disease to individual coronary arteries in our patients with some differences in the subgroups. Agreement between coronary angiogram and 99mTc sestamibi for the extent of coronary artery disease was also satisfactory.  相似文献   
54.
BACKGROUND: The histologic criteria defining bronchioloalveolar carcinoma (BAC) were recently revised, but it is unclear whether these criteria predict clinical behavior. This study determined the outcome of resected BAC in relationship to clinical and radiologic disease pattern, and pathologic features. METHODS: Between 1989 and 2000, 100 consecutive surgically treated patients with adenocarcinomas exhibiting various degrees of BAC features were retrospectively studied. Histology was reviewed; tumors were classified as pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features. Clinical and radiologic pattern were classified as unifocal, multifocal, or pneumonic. Demographic data, tumor stage, and outcome were recorded. Survival was analyzed by the Kaplan-Meier method, and prognostic factors were determined by the log-rank test. RESULTS: Patient median age was 65, and 74% of the patients were female. Pure BAC, BAC with focal invasion, and adenocarcinoma with BAC features occurred in 47, 21, and 32 patients, respectively. Unifocal disease occurred in 64 patients, multifocal in 29, and pneumonic in 7. Seventy-one patients had stage I/II tumors, 22 had stage III/IV, and 7 patients had Stage X tumors. Overall 5-year survival was 74%. There was no significant difference in survival among the three histologic subtypes. The pneumonic pattern had significantly worse survival compared with unifocal and multifocal patterns. Pathologic stage predicted survival, with 5-year survivals for I/II and III/IV of 83.7% and 59.6%, respectively. CONCLUSIONS: Clinical pattern and pathologic stage, but not the degree of invasion on histologic examination predict survival. Multifocal disease is associated with excellent long-term survival after resection. The favorable survival of stage III/IV BAC indicates that the current staging system does not fully describe this disease in patients undergoing resection because of its distinct tumor behavior.  相似文献   
55.
PURPOSE: To analyze acute lung toxicity data of non-small-cell lung cancer patients treated with three-dimensional conformal radiation therapy in terms of dosimetric variables, location of dose within subvolumes of the lungs, and models of normal-tissue complication probability (NTCP). METHODS AND MATERIALS: Dose distributions of 49 non-small-cell lung cancer patients treated in a dose escalation protocol between 1992 and 1999 were analyzed (dose range: 57.6-81 Gy). Nine patients had RTOG Grade 3 or higher acute lung toxicity. Correlation with dosimetric and physical variables, as well as Lyman and parallel NTCP models, was assessed. Lungs were evaluated as a single structure, as superior and inferior halves (to assess significance of dose to upper and lower lungs), and as ipsilateral and contralateral lungs. RESULTS: For the whole lung, Grade 3 or higher pneumonitis was significantly correlated (p 0.5 for superior lung indices, and >0.1 for contralateral lung indices studied). CONCLUSIONS: For these patients, commonly used dosimetric and NTCP models are significantly correlated with >or= Grade 3 pneumonitis. Equivalently strong correlations are found in the lower portion of the lungs and the ipsilateral lung, but not in the upper portion or contralateral lung.  相似文献   
56.
BMP mRNA and protein expression in the developing mouse olfactory system   总被引:6,自引:0,他引:6  
The bone morphogenetic proteins (BMPs) play fundamental roles during the organization of the central nervous system. The presence of these proteins has also been demonstrated in regions of the adult brain that are characterized by neural plasticity. In this study, we examined the expression of BMP4, 6, and 7 mRNAs and proteins in the murine olfactory system. The olfactory system is a useful model for studying cell proliferation and neural differentiation because both of these processes persist throughout life in the olfactory epithelium (OE) and olfactory bulb (OB). Our results demonstrate a differential expression of BMP4, 6, and 7 in the embryonic, postnatal, and adult olfactory system. In particular, BMP4 and BMP7 showed similar immunostaining patterns, being expressed in the olfactory region from the earliest stages studied (embryonic day 15.5) to adulthood. During development BMPs were expressed in the OE, olfactory bulb nerve layer, glomerular layer (GL), mitral cell layer (MCL), and subventricular zone. During the first postnatal week of life, BMP4 and 7 immunoreactivity (-ir) was particularly evident in the GL, MCL, and in the subependymal layer (SEL), which originates postnatally from the subventricular zone. In adults, BMP4 and 7 immunostaining was present in the GL and SEL. Within the SEL, BMP4 and 7 proteins were expressed primarily in association with the astrocytic glial compartment. BMP6-ir was always found in mature olfactory receptor neurons and their axonal projections to the OB. In summary, these data support the hypothesis that BMPs play a role in the morphogenesis of the olfactory system during development and in its plasticity during adulthood.  相似文献   
57.
Clinical trials must be well designed in order to produce statistically and clinically significant results. This article describes the randomisation techniques that can prevent bias, the importance of sample size and the concept of power analysis.  相似文献   
58.
The intensive care unit at Queen Elizabeth Central Hospital (QECH) has 4 beds and offers level 2 care. A retrospective audit of all admissions to the unit during 2002 was carried out. There were a total of 339 admissions giving a bed occupancy rate of 82 %. Surgical patients made up 81 % of admissions. 45% of all admissions were ventilated. Overall mortality was 38%. Ventilated patients had a mortality of 71% compared with 10% for non-ventilated. Data are also presented for mortality within the surgical and paediatric surgical admissions.  相似文献   
59.
60.
BACKGROUND: Surgical resection of malignant pleural mesothelioma is reported to have up to an 80% rate of local recurrence. We performed a phase II trial of high-dose hemithoracic radiation after complete resection to determine feasibility and to estimate rates of local recurrence and survival. METHODS: Patients were eligible if they had a resectable tumor, as determined by computed tomographic scanning, and adequate cardiopulmonary function for extrapleural pneumonectomy or pleurectomy/decortication. After complete resection, patients received hemithoracic radiation (54 Gy) and then were followed up with serial computed tomographic scanning. RESULTS: From 1995 to 1998, 88 patients (73 men and 15 women; median age, 62.5 years) were entered into the study. The operations performed included 62 extrapleural pneumonectomies (70%) and 5 pleurectomies/decortications; procedures for exploration only were performed in 21 patients. Seven (7.9%) patients died postoperatively. Adjuvant radiation administered to 57 patients (54 undergoing extrapleural pneumonectomy and 3 undergoing pleurectomy/decortication) at a median dose of 54 Gy was well tolerated (grade 0-2 fatigue, esophagitis), except for one late esophageal fistula. The median survival was 33.8 months for stage I and II tumors but only 10 months for stage III and IV tumors (P =.04). For the patients undergoing extrapleural pneumonectomy, the sites of recurrence were locoregional in 2, locoregional and distant in 5, and distant only in 30. CONCLUSION: Hemithoracic radiation after complete surgical resection at a dose not previously reported is feasible. This approach dramatically reduces local recurrence and is associated with prolonged survival for early-stage tumors. Stage III disease has a high risk of early distant relapse and should be considered for trials of systemic therapy added to this regimen of resection and radiation.  相似文献   
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