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81.
R. J. Healey M.D. A. H. Leff M.D. B. D. Rosenak M.D. 《Digestive diseases and sciences》1959,4(8):638-641
Summary A case of primary miliary tuberculosis of the liver was proved by positive culture of needle biopsy specimen. 相似文献
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A well-distributed, patent microvascular network is essential for adequate, uniform delivery of chemotherapy into solid tumors. This network has not been evaluated in osteogenic sarcoma. Sp?lteholz tissue clarification was used to observe the microvasculature of canine humeri bearing osteogenic sarcoma. Freshly amputated limbs, obtained from therapeutic amputation, were infused with a micron-sized carbon particle solution, frozen, and then cut into sagittal and axial 0.5-mm thick sections. They were photographed, then radiographed using high resolution Faxitron xray, chemically treated to clarify the tissue, and then rephotographed. Microvasculature was identified by the localization of carbon particles, which were unaffected by the clarification process, within the clarified sections. Clarified section photographs were digitized to gray scale levels and analyzed using IMAGE software; levels are directly related to capillary density. Faxitron and original images were registered to the clarified images to identify tissue regions. Multiple regions of interest from normal muscle, fat, bone, and tumor regions were selected and averaged. The microvasculature of the tumor was inhomogeneous, whereas its density was considerably lower than normal adjacent muscle and bone (range, 56-72% lower). These findings suggest that insufficient microvascular density and distribution may provide additional explanation for the poor response of solid tumors to chemotherapy and radiation therapy. 相似文献
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PURPOSE: To assess whether thyroid disease is independently associated with open-angle glaucoma (OAG), using history of thyroid disease and current thyroxine use. METHODS: The Blue Mountains Eye Study examined 3654 persons, aged 49-97 years. Interviewers collected self-reported history of diagnosis and treatment for thyroid disease. Eye examinations included applanation tonometry, stereoscopic optic disc photography and automated perimetry. OAG was diagnosed from the presence of matching typical glaucomatous field changes and optic disc cupping, independent of intraocular pressure. Associations between thyroid disease (history and treatment) and OAG were assessed in a multivariate model. RESULTS: Of 324 participants (8.9%) reporting history of thyroid disease, 147 (4.0%) were currently using thyroxine. Although we could not accurately categorize the thyroid disorder for all cases, current use of thyroxine suggests a prior hypothyroid state. All thyroid disease subgroups affected women more frequently than men, P=0.001. OAG was diagnosed in 108 subjects (3.0%) and was more frequent in those reporting past thyroid disease (4.6 vs 2.8%). This relationship was not statistically significant after adjusting for potential confounders, multivariate odds ratio (OR) 1.6; 95% confidence interval (95% CI) 0.9-2.9. OAG was significantly more frequent, however, in subjects reporting current thyroxine use (6.8 vs 2.8%), multivariate OR 2.1; 95% CI 1.0-4.4, or history of thyroid surgery (6.5 vs 2.8%), multivariate OR 2.5; 95% CI 1.0-6.2. CONCLUSIONS: This population-based study suggests that thyroid disease, indicated by current thyroxine use or past thyroid surgery, could be independently related to OAG. 相似文献
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Rendell JM Juszczak E Hainsworth J Gucht EV Healey C Morriss R Ferrier N Young AH Young H Goodwin GM Geddes JR 《Bipolar disorders》2004,6(1):26-31
Objectives: The initial design of the BALANCE (Bipolar Affective disorder: Lithium / ANtiConvulsant Comparative Evaluation) Trial of maintenance treatment for bipolar disorder was based on the experience of previous trials in bipolar disorder and psychiatry and on the methods developed for large randomized trials in other areas of medicine. This report describes the adaptations to the initial design and trial procedures following the initial phases of the study. The rationale for the trial and full protocol have been published elsewhere.
Methods: A pilot study and start-up phase were used to check the tolerability of the interventions, refine the trial design and develop trial procedures that are acceptable to both clinicians and patients.
Results: Changes to the procedures included: the dropping of masking of allocated treatment from clinicians and participants; introduction of the use of postal delivery to supply medication; and dispensing with the proposed schedule of regular follow up appointments. In addition, support was made available to participating psychiatrists who often had limited experience of participating in randomized trials.
Conclusions: Pilot studies and start-up phases are essential to refine clinical trial design and allow development of procedures that are both methodologically rigorous and flexible and robust enough to promote recruitment and follow up. BALANCE is now actively recruiting in the UK and USA. 相似文献
Methods: A pilot study and start-up phase were used to check the tolerability of the interventions, refine the trial design and develop trial procedures that are acceptable to both clinicians and patients.
Results: Changes to the procedures included: the dropping of masking of allocated treatment from clinicians and participants; introduction of the use of postal delivery to supply medication; and dispensing with the proposed schedule of regular follow up appointments. In addition, support was made available to participating psychiatrists who often had limited experience of participating in randomized trials.
Conclusions: Pilot studies and start-up phases are essential to refine clinical trial design and allow development of procedures that are both methodologically rigorous and flexible and robust enough to promote recruitment and follow up. BALANCE is now actively recruiting in the UK and USA. 相似文献
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We report a case of severe intrauterine growth retardation (IUGR) and hypospadias in association with trisomy 22 diagnosed following chorionic villus sampling (CVS). Subsequent analysis of amniotic fluid cultures showed a normal male karyotype, 46,XY. As a previous case had been reported with similar abnormalities, in association with maternal uniparental disomy (UPD) 22, molecular studies were also performed. Microsatellite marker studies showed biparental inheritance. Follow-up studies after delivery showed a normal cell line in lymphocytes with the trisomy appearing to be confined to the placenta. The present case concurs with other earlier reports that maternal UPD for chromosome 22 has no impact on the phenotype. The features seen in the fetus are most likely the result of placental dysfunction due to trisomy, tissue-specific mosaicism and/or the effects of local growth restriction. 相似文献
89.
The importance of evidence in teaching and in support of clinical decisions is well established in health care, including dentistry. Defence of clinical decisions increasingly requires reliable data or evidence to support the stance taken. Assistance in finding the best evidence comes from a variety of sources, including computerised databases, journals, continuing education meetings, and study clubs. The randomised controlled trial heads the hierarchy of research designs on which evaluation of evidence is based; anecdotally based evidence and individual case studies are the least preferred study designs. Evaluation of a study requires a number of questions to be asked to determine how the study was performed, and whether it applies to a clinical situation. These questions relate to how the study was carried out, whether controls were used, were the results likely to be valid, and was statistical and clinical significance present. Quackery, pressure from consumers, and legal considerations have contributed to an increase in the importance of evidence-based practice. The benefits, however, of evidence-based practice are that treatment decisions are easier to justify, especially when there is a complaint or a dento-legal issue, and the personal satisfaction that patients are being offered the best treatment. 相似文献
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