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排序方式: 共有1307条查询结果,搜索用时 312 毫秒
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Renuka V. Iyer MD Bhavana Konda MD MPH Christos Fountzilas MD Sarbajit Mukherjee MD MS Dwight Owen MD MS Kristopher Attwood PhD Chong Wang MA Orla Maguire PhD Hans Minderman PhD Sheryl-Ann Suffren BA Karen Hicks BS John Wilton PhD Robert Bies PhD Danielle Casucci BA Diane Reidy-Lagunes MD Manisha Shah MD 《Cancer》2020,126(16):3689-3697
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MC Chau SF Leung KM Kam KY Cheung WH Kwan KH Yu KW Chiu TC Chan 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):480-484
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process. 相似文献
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Four patients with persistent oligospermia and necrospermia were found to have severely degenerated sperm in the ejaculate. However, in those examined, testicular sperm were ultrastructurally normal, indicating that sperm degeneration and death was occurring during epididymal passage or storage or both or upon mixing with the seminal plasma at ejaculation. Seminal plasma was found to be nontoxic to normal donor sperm. In three patients, frequent ejaculation (two ejaculates per day for 4 or 5 days) was used to deplete epididymal sperm reserves and reduce the period spent in the epididymis. This resulted in a threefold to sevenfold increase in percentage of motile sperm in the ejaculate and a similar increase in sperm motility index. The authors propose the term "epididymal necrospermia" to describe this previously undefined type of male infertility. 相似文献
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P Wilton 《Acta paediatrica Scandinavica》1987,76(2):193-200
Most girls with Turner's syndrome seemed to increase their growth rate during the first year of growth hormone treatment. The gain is rarely more than 3 cm/year. In 3 studies the combination of growth hormone and an anabolic steroid resulted in higher growth rates compared to those with each individual compound. The results of long-term treatment (more than one year) also appear to be positive. The impact of growth hormone therapy on final height has not yet been established, however. 相似文献
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Effect of metabolic control and duration on exercise-induced albuminuria in diabetic teen-agers 总被引:1,自引:0,他引:1
G Dahlquist A Aperia L Carlsson T Linné B Persson C Thorén P Wilton 《Acta paediatrica Scandinavica》1983,72(6):895-902
Nineteen type I diabetic teen-agers without clinical signs of nephropathy with a duration of diabetes varying from 3 to 16.8 years were examined by a standardized exercise test for analysis of urinary excretion of albumin and beta 2-microglobulin. The patients were studied both in poor and improved (but not perfect), metabolic control as defined by HbA1c and blood glucose profiles, and the values were compared to those of 14 age-matched healthy controls. The controls showed no increase in albumin excretion rate during exercise as was found in diabetic patients. The albumin excretion rate during exercise was significantly correlated (p less than 0.05) to systolic blood pressure in the diabetic patients. Blood pressure in the diabetic patients was, however, similar to that of controls both at rest and during exercise. Urinary beta 2-microglobulin did not change during exercise. The urinary albumin excretion during exercise decreased significantly with improved metabolic control in diabetic patients, but the albumin excretion rate was not correlated with either blood or urinary glucose or diuresis during the exercise test. When metabolic control was improved there was a significant correlation between the increase in albumin excretion rate during exercise and the duration of diabetes, indicating that part of the exercise-induced albumin excretion might reflect irreversible morphological changes in the diabetic kidney. This test might therefore have a predictive value for diabetic nephropathy if performed during strict metabolic control. 相似文献
58.
OBJECTIVES: To conduct a systematic review of the literature to describe and critically appraise studies reporting on the cost and/or effectiveness of interventions proposed to control the emergence of antimicrobial resistance (AMR). METHODS: The search for relevant studies encompassed consultation with world experts in AMR, and electronic bibliographic database search of: Medline (1960-2000); ISI (1981-2000); EMBASE (1988-2000); Grey Literature (1999-2000); Database of Reviews of Effectiveness (DARE) and the NHS Health Economic Evaluation Database (HEED) at York University's Centre for Reviews and Dissemination (CRD) (numerous years); OPAC (1975-2000); and the Cochrane Library Online (1990-2000). Only studies that concerned the effectiveness or cost-effectiveness of measures specifically designed to contain the emergence of AMR were reviewed. Standardised data extraction sheets, based on existing checklists for effectiveness and cost-effectiveness, were used to assess the validity of each study using the 'risk of bias criteria' suggested in the Cochrane Handbook. Only studies categorised as being at low or moderate risk of bias were reported fully. The reliability of the data review process was monitored by comparison of several, random, independent assessments by all authors. The mix of study methods (i.e. including studies based on non-randomised controlled trials) meant that formal meta-analysis was not possible, and thus a qualitative review was performed. RESULTS: In total, 43 studies were reviewed, with 21 classed as being at moderate or low risk of bias and therefore reported in the paper. These studies covered policies on: restricting the use of antimicrobials (five studies, suggesting that restriction policies can alter prescriber behaviour, although with limited evidence of subsequent effect on AMR); prescriber education, feedback and use of guidelines (six studies, with no clear conclusion); combination therapies (seven studies, showing the potential to lower drug-specific resistance, although for an indeterminate time period); vaccination (three studies showing cost/effectiveness). Most of these studies were: from the developed world, principally the USA; hospital-based, with few community level interventions; and concerned with effectiveness, not cost-effectiveness. CONCLUSIONS: Overall, there is an absence of good evidence concerning what is effective, and especially cost-effective, in reducing the emergence of AMR. However, in addition to more research concerning these forms of intervention, the paper highlights four specific areas for further investigation: validating intermediate or surrogate outcome measures to enable better use to be made of the literature on intermediate measures; development and evaluation of 'macro' strategies; research into specific aspects of AMR in developing countries; and empirical and methodological research concerning the economic evaluation of interventions. 相似文献
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Waterston–Cooley anastomosis may be carried out in patients with tricuspid atresia to provide pulmonary perfusion. It is associated with several complications, including preferential blood flow to the right lung, hypoplasia of the left pulmonary artery, obstruction of the anatomosis or rupture of pulmonary aneurysms. We study a patient with thrombosis in the pulmonary arteries following surgical construction of a Waterston shunt in childhood. Imaging findings and clinical symptoms are discussed with emphasis on echocardiogram‐gated multislice spiral CT. 相似文献