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1.
There have been suggestions that urine samples positive for benzoylecognine, the diagnostic metabolite of cocaine, may be the result of consumption Mate de Coca, a commercially available tea made from coca (Erythroxylon coca) leaves. The Jockey Club in Great Britain commissioned research into this subject as several jockeys have tested positive for benzoylecognine over the past few years. Urine samples collected at various time points within 24 h after ingestion of a 250 ml infusion of Mate de Coca tea were analysed using three different methods. All samples tested positive for benzoylecognine.  相似文献   

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Histerosalpingography is the most commonly used technique in the evaluation of infertility. It has traditionally been considered the gold standard for assessment of Fallopian tubes giving information about their patency and morphology. It is also recommended for the study of the uterine cavity. With a good knowledge about the anatomy and the variants of the normality, and a good technique, we can do a good differential diagnosis between normality and pathology, which probably it will need more tests.  相似文献   

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OBJECTIVE: Nuclear medicine technologists work under significant radiation protection constraints. These constraints are based on the linear no-threshold (LNT) radiation paradigm, which was developed in the 1960s and was based largely on the deleterious effects of radiation as they were understood at the time. More recently, the theory of radiation hormesis, or a beneficial effect of low-level exposure to radiation, has gained recognition. This article reviews the history of attitudes toward radiation, describes the radiation hormesis hypothesis, examines some of the evidence that supports it, and suggests ways that radiation protection regulations might change if the hypothesis were to become accepted.  相似文献   

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In these three words--genomics, proteomics and nanotechnologies--is the future of medicine of the third millennium, which will be characterised by more careful attention to disease prevention, diagnosis and treatment. Molecular imaging appears to satisfy this requirement. It is emerging as a new science that brings together molecular biology and in vivo imaging and represents the key for the application of personalized medicine. Micro-PET (positron emission tomography), micro-SPECT (single photon emission computed tomography), micro-CT (computed tomography), micro-MR (magnetic resonance), micro-US (ultrasound) and optical imaging are all molecular imaging techniques, several of which are applied only in preclinical settings on animal models. Others, however, are applied routinely in both clinical and preclinical setting. Research on small animals allows investigation of the genesis and development of diseases, as well as drug efficacy and the development of personalized therapies, through the study of biological processes that precede the expression of common symptoms of a pathology. Advances in molecular imaging were made possible only by collaboration among scientists in the fields of radiology, chemistry, molecular and cell biology, physics, mathematics, pharmacology, gene therapy and oncology. Although until now researchers have traditionally limited their interactions, it is only by increasing these connections that the current gaps in terminology, methods and approaches that inhibit scientific progress can be eliminated.  相似文献   

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Physical activity and sports participation are promoted to counteract the increased prevalence of overweight and obesity in children and young adults. Both high body mass index and physical activity level have been associated with an increased risk of sports injuries. The objective is to determine the relationship between sports injuries and overweight in sports participants (4–24 years), taking physical activity into account. Data were obtained from the 2006–2011 “Injuries and Physical Activity in the Netherlands” survey. Analyses were based on a representative sample of 3846 sports participants (4–24 years). Univariate and multiple logistic regression analyses were applied to investigate the association between sports injury and weight status. Of all the sports participants, 14.7% were overweight. Compared with normal‐weight sports participants, the odds of sustaining a sports injury was 0.73 [confidence interval (CI): 0.53–1.00, P = 0.050] for overweight sports participants; the odds for underweight sports participants was 0.80 (CI: 0.56–1.15, P = 0.226). There is some evidence that overweight sports participants (4–24 years) do not have an increased injury risk compared with normal‐weight sports participants, even when the level of physical activity is taken into account. Additional research is recommended regarding overweight people who start to participate in a physically active lifestyle.  相似文献   

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PurposeThis review examines the role of permanent radioactive seed implantation in thoracic malignancy. This technique can be used intraoperatively to provide additional highly localized radiation therapy in cases where optimal oncologic margins are unattainable or to palliate unresectable disease.Methods and materialsRelevant trials were identified through a systematic literature search using Pubmed.ResultsThe intraoperative placement of brachytherapy seeds has been described after sublobar resection for non–small-cell lung cancer (NSCLC), where surgical margins are close or microscopically positive and in the presence of macroscopic residual disease. This brachytherapy technique is currently the focus of a randomized prospective trial in the USA in patients unfit for lobectomy for early-stage NSCLC.ConclusionsThis review summarizes the methods of brachytherapy seed placement and the published experience of brachytherapy implants within the thorax, also examining radiation safety and postoperative dosimetry. This technique has the potential to improve local control with optimal sparing of normal tissue owing to its highly conformal radiotherapy delivery.  相似文献   

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The hypothesis of this study was that length, torsion, and axis of a leg phantom can be measured accurately and reproducibly by magnetic resonance imaging (MRI) and that this can be applied to patients with leg deformities. Two phantoms and 30 patients (genu varum, n = 15; genu valgum, n = 15) were investigated using an optimized MRI technique. Reference measurements were performed with a micrometer screw and a goniometer. Patient leg length and axis were compared with long radiographs in bipedal stance. Intra- and interobserver reproducibility and accuracy were calculated using the mean absolute difference (MAD) and the 95% confidence interval. In patients, comparisons were done using a paired Student's t-test. MAD, intraobserver MAD, and interobserver MAD were 0.03, 0.03, 0.04 mm (length); 0.98, 1.2, 0.98 degrees (torsion); and 0.18, 0.23, 0.22 degrees (axis), respectively. In patients, leg length was underestimated by MRI (-2.4 +/- 0.7%; 1.9 +/- 0.7 cm; P < 0.001). The hip-knee-ankle angle (HKA) did not show significant differences in varus knees (-0.5 +/- 1.0 degrees ; P > 0.05), while it was significantly underestimated in valgus knees (-3.6 +/- 2.8 degrees ; P < 0.05). The phantom study revealed that leg length, torsion, and axis can be measured accurately and reproducibly by MRI. Although underestimation of leg length and HKA in valgus knees occurred, this optimized MRI technique can be applied to patients with leg deformities.  相似文献   

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We performed palliative radiotherapy with a single-fraction of 8 Gy using a three-dimensional conformal radiotherapy (3D-CRT) technique for patients with dyspnea due to a bulky nasooropharyngeal lesion who had chemotherapy-refractory, recurrent, aggressive lymphoma. After palliative radiotherapy, a complete response with acceptable toxicity was achieved at the irradiated sites of two patients, and the symptoms resolved completely. These results indicated that a single fraction of 8 Gy using 3D-CRT is an effective palliative treatment for chemotherapy-refractory, recurrent, aggressive lymphoma.  相似文献   

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PURPOSE: The purpose of this article is to illustrate a case where acquisition of digital imaging know-how by a modern radiotherapy division has helped to solve a technical problem while allowing substantial savings through the use of free and open-source resources. The problem was related to the necessity to route, with complex policies, the images produced by different digital imaging and communications in medicine (DICOM) sources within the department or in other divisions and/or hospitals. MATERIALS AND METHODS: The problem was solved by using completely free, well-tested and stable technologies (PHP, Apache, MySQL, DCMTK OFFIS, Red Hat Linux 9A and Linux Fedora Core 4) and low-cost hardware to contain costs. In the development, we also considered integration of the routed images with the existing electronic clinical records. RESULTS: The system developed, called the dicom router, implemented two kinds of routing: manual and automatic, both oriented to link the images acquired with the existing electronic clinical records. System stability was enhanced in a second phase by using a low-cost hardware redundancy solution. The system has now been operating for 1 year and has proved the value of the technologies used. CONCLUSIONS: The need to operate with more than one provider creates a series of integration issues, so that it becomes economically appealing to acquire internally the knowledge needed to interact more precisely with providers of big information technology (IT) solutions. This need is well catered for by open-source technologies, which are well documented and available to everyone. By using them, in-house IT technicians are able to implement valuable technical solutions for small-to medium-sized informatization problems, which would otherwise remain unsolved except with great economic efforts.  相似文献   

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《Brachytherapy》2014,13(6):632-639
PurposeBrachytherapy dose calculation is commonly performed using the Task Group-No 43 Report-Updated protocol (TG-43U1) formalism. Recently, a more accurate approach has been proposed that can handle tissue composition, tissue density, body shape, applicator geometry, and dose reporting either in media or water. Some model-based dose calculation algorithms are based on Monte Carlo (MC) simulations. This work presents a software platform capable of processing medical images and treatment plans, and preparing the required input data for MC simulations.Methods and MaterialsThe A Medical Image-based Graphical platfOrm—Brachytherapy module (AMIGOBrachy) is a user interface, coupled to the MCNP6 MC code, for absorbed dose calculations. The AMIGOBrachy was first validated in water for a high-dose-rate 192Ir source. Next, dose distributions were validated in uniform phantoms consisting of different materials. Finally, dose distributions were obtained in patient geometries. Results were compared against a treatment planning system including a linear Boltzmann transport equation (LBTE) solver capable of handling nonwater heterogeneities.ResultsThe TG-43U1 source parameters are in good agreement with literature with more than 90% of anisotropy values within 1%. No significant dependence on the tissue composition was observed comparing MC results against an LBTE solver. Clinical cases showed differences up to 25%, when comparing MC results against TG-43U1. About 92% of the voxels exhibited dose differences lower than 2% when comparing MC results against an LBTE solver.ConclusionThe AMIGOBrachy can improve the accuracy of the TG-43U1 dose calculation by using a more accurate MC dose calculation algorithm. The AMIGOBrachy can be incorporated in clinical practice via a user-friendly graphical interface.  相似文献   

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PurposeWe report the long-term outcomes of pulse-dose rate (PDR) brachytherapy used in a nonstandard style (pseudo-PDR) with an high-dose rate brachytherapy technique in conjunction with external beam radiotherapy (EBRT) and hormonal manipulation on prostate cancer (PC).Methods and MaterialsWe treated 253 patients with Stage T1–T3 N0M0 PC, between December 1999 and March 2006. All patients received neoadjuvant androgen deprivation for a median 6 months. Treatment consisted of three pulses of pseudo-PDR brachytherapy to a median dose of 18 Gy with 50.4 Gy in 28 fractions of EBRT.ResultsAt a median 6 years followup, (range, 1–11 years), 5-year overall survival was 92%, and PC-specific survival was 96%. The 5-year biochemical control (biochemical no evidence of disease) by the Phoenix definition for low-, intermediate-, and high-risk groups was 95%, 90%, and 71%, respectively (p < 0.00001). At 6 years, the incidence of Radiotherapy Oncology Group Grade 2 and 3 genitourinary toxicity was 1% and 6%; Radiotherapy Oncology Group Grade 2 and 3 gastrointestinal toxicity was 4% and 0%. Erectile preservation at 3 years was 58%. The Phoenix definition best predicted clinical failure with a high specificity (94%).ConclusionsPseudo-PDR brachytherapy plus EBRT with limited neoadjuvant hormonal manipulation is an effective treatment option in localized PC, with minimal and tolerable morbidity and provides excellent control. This technique of a modified PDR-delivery technique appears as effective as high-dose rate therapy.  相似文献   

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PURPOSE: Our aim was to evaluate how many medical requests for US, CT and MR outpatients exams are inadequate. MATERIALS AND METHODS: We evaluated three series of consecutive requests for outpatients exams, distinguishing firstly the adequate from the inadequate requests. The inadequate requests were classified as: (A) absence of real indication; (B) lacking or vague clinical query; (C) absence of important information on patient's status. US requests concerned 282 patients for 300 body segments, as follows: neck (n=50); upper abdomen (n=95); lower abdomen (n=12); upper and lower abdomen (n=84); musculoskeletal (n=32); other body segments (n=27). CT requests concerned 280 patients for 300 body segments, as follows: chest (n=67); abdomen (n=77); musculoskeletal (n=94); other body segments (n=62). MR musculoskeletal requests concerned 138 patients for 150 body segments, as follows: knee (n=87); ankle (n=13); shoulder (n=28) , other body segments (n=22). RESULTS: A total of 228/300 US requests (76%) were inadequate, ranging from 66% (musculoskeletal) to 86% (neck), classified as: A, 21/228 (9%); B, 130/228 (57%); C, 77/228 (34%). A total of 231/300 (77%) body CT requests were inadequate, ranging from 72% (chest) to 86% (musculoskeletal), classified as: A, 22/231(10%); B, 88/231(38%); C, 121/231(52%). A total of 124/150 (83%) MR musculoskeletal requests were inadequate, ranging from 69% (ankle) to 89% (knee), classified as: A, 12/124(10%); B, 50/124(40%); C, 62/124 (50%). No significant difference was found among the levels of inadequacy for the three techniques and among the body segments for each of the three techniques. CONCLUSIONS: The majority of the medical requests for outpatient exams turned out to be inadequate. A large communication gap between referring physicians and radiologists needs to be filled.  相似文献   

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Exercise generally results in less weight loss than expected and it is frequently observed that men and women do not respond equally to exercise for weight loss. This may be caused by differences in compensation by other components of energy balance or to differences in the energy expenditure of exercise observed between genders.  相似文献   

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