BACKGROUND Classic “do not touch” and benign osseous lesions are sometimes detected on 18-Ffluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) studies. These lesions are often refe...BACKGROUND Classic “do not touch” and benign osseous lesions are sometimes detected on 18-Ffluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) studies. These lesions are often referred for biopsy because the physician interpreting the PET/CT may not be familiar with the spectrum of 18F-FDG uptake patterns that these lesions display. AIM To show that “do not touch” and benign osseous lesions can have increased 18FFDG uptake above blood-pool on PET/CT;therefore, the CT appearance of these lesions should dictate management rather than the standardized uptake values (SUV). METHODS This retrospective study evaluated 287 independent patients with 287 classic “do not touch”(benign cystic lesions, insufficiency fractures, bone islands, bone infarcts) or benign osseous lesions (hemangiomas, enchondromas, osteochondromas, fibrous dysplasia, Paget’s disease, osteomyelitis) who underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) at a tertiary academic healthcare institution between 01/01/2006 and 12/1/2018. The maximum and mean SUV, and the ratio of the maximum SUV to mean blood pool were calculated. Pearson’s correlations between lesion size and maximum SUV were calculated. RESULTS The ranges of the maximum SUV were as follows: For hemangiomas (0.95-2.99), bone infarcts (0.37-3.44), bone islands (0.26-3.29), enchondromas (0.46-2.69), fibrous dysplasia (0.78-18.63), osteochondromas (1.11-2.56), Paget’s disease of bone (0.93-5.65), insufficiency fractures (1.06-12.97) and for osteomyelitis (2.57- 12.64). The range of the maximum SUV was lowest for osteochondromas (maximum SUV 2.56) and was highest for fibrous dysplasia (maximum SUV of 18.63). There was at least one lesion that demonstrated greater 18F-FDG avidity than the blood pool amongst each lesion type, with the highest maximum SUV ranging from 9.34 times blood pool mean (osteomyelitis) to 1.42 times blood pool mean (hemangiomas). There was no correlation between the maximum SUV and the lesion size except for enchondromas. Larger enchondromas had higher maximum SUV (r = 0.36, P = 0.02). CONCLUSION The classic “do not touch” lesions and classic benign lesions can be 18F-FDG avid. The CT appearance of these lesions should dictate clinical management rather than the maximum SUV.展开更多
Iris du Pré, a professional pianist, wanted a second child, did not conceive quickly and was injected in 1944 by a doctor in Oxford with pregnant mare serum gonadotropin (PMSG). The doctor joked “This child will...Iris du Pré, a professional pianist, wanted a second child, did not conceive quickly and was injected in 1944 by a doctor in Oxford with pregnant mare serum gonadotropin (PMSG). The doctor joked “This child will be a racehorse winner!” In January 1945, Jacqueline du Pré, the remarkable, world-famous cellist was born. In the 1920's and 1930's, animal experimentation and clinical studies had shown that pituitary glycoproteins stimulated the ovary (follicle-stimulating hormone, FSH) and the corpus luteum (luteal-stimulating hormone, LH) which prepared the human womb for embedding a fertilized ovum and that pregnant mare’s blood and urine contained the glycoprotein, PMSG whose origin was placental cells, but surprisingly in humans had the actions of both FSH and LH. However, the PMSG serum alone did not bring about pregnancy. The doctor did not know that without subsequent injection of another factor in correct sequence and timing, PMSG was pointless. In 1947, a placental glycoprotein, found in the 1920's in urine of pregnant women (human chorionic gonadotropin, hCG), when injected in mice subsequent to PMSG, achieved ovulation but not pregnancy. Human application of those findings was extremely risky due to impurities (up to 95%). The Federal Drug Administration (FDA), established in 1938, requested easily bye-passed marketing safety. Companies offered material “sufficiently” purified;professional bodies negated clinical use, tempting to a few. Evidence also suggests that, to sustain pregnancy the doctor also prescribed the new “eostrogen”, diethyl stilbestrol (DES) of negative fame. In 1947, the Nuremberg Code of ethics demanded human experiments by qualified personnel and trials preceded by adequate animal studies. It is not the case here. From five, du Pré had a most exceptional musical memory, almost obsessive musicality and a very difficult school-time socially. Later history: adult masculine build, awkward gait, tendency to recurrent depressions from mid-adolescence, unbalanced thyroidal metabolism, symptoms of numbness in late teens, long breaks for rest from age 25, MS diagnosis at 28 when unable to play, death aged 42. Yet at sixteen and after, she astounded all with technique, passion and unique musical interpretation. Her husband, an outstanding musician: “She had a capacity to imagine sound such as I never met in any other musician”. A close musician colleague: “... it was done before she was born”;perhaps much closer to the truth than realization, for her history it may suggest a fetal neurodevelopment abused in the womb.展开更多
本文从目前对"do you think"做插入语的普遍认识着手,用乔姆斯基的最简方案理论解释并阐明"do you think"句的生成过程,澄清"do you think"非但不是插入语,还是很重要的句子成分。并进一步讨论了"do...本文从目前对"do you think"做插入语的普遍认识着手,用乔姆斯基的最简方案理论解释并阐明"do you think"句的生成过程,澄清"do you think"非但不是插入语,还是很重要的句子成分。并进一步讨论了"do you think"和"do you know"两个看似相似的句型为何在使用上会存在很大的差别。也希望由此引起学者们对功能语言学与形式语言学在解释实际问题上存在的分歧给予更多讨论,关注英语教学中的一些解释性错误。展开更多
针对网联车队列系统易受到干扰和拒绝服务(Denial of service, DoS)攻击问题,提出一种外部干扰和随机DoS攻击作用下的网联车安全H∞队列控制方法.首先,采用马尔科夫随机过程,将网联车随机DoS攻击特性建模为一个随机通信拓扑切换模型,据...针对网联车队列系统易受到干扰和拒绝服务(Denial of service, DoS)攻击问题,提出一种外部干扰和随机DoS攻击作用下的网联车安全H∞队列控制方法.首先,采用马尔科夫随机过程,将网联车随机DoS攻击特性建模为一个随机通信拓扑切换模型,据此设计网联车安全队列控制协议.然后,采用线性矩阵不等式(Linear matrix inequality, LMI)技术计算安全队列控制器参数,并应用Lyapunov-Krasovskii稳定性理论,建立在外部扰动和随机DoS攻击下队列系统稳定性充分条件.在此基础上,分析得到该队列闭环系统的弦稳定性充分条件.最后,通过7辆车组成的队列系统对比仿真实验,验证该方法的优越性.展开更多
文摘BACKGROUND Classic “do not touch” and benign osseous lesions are sometimes detected on 18-Ffluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) studies. These lesions are often referred for biopsy because the physician interpreting the PET/CT may not be familiar with the spectrum of 18F-FDG uptake patterns that these lesions display. AIM To show that “do not touch” and benign osseous lesions can have increased 18FFDG uptake above blood-pool on PET/CT;therefore, the CT appearance of these lesions should dictate management rather than the standardized uptake values (SUV). METHODS This retrospective study evaluated 287 independent patients with 287 classic “do not touch”(benign cystic lesions, insufficiency fractures, bone islands, bone infarcts) or benign osseous lesions (hemangiomas, enchondromas, osteochondromas, fibrous dysplasia, Paget’s disease, osteomyelitis) who underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) at a tertiary academic healthcare institution between 01/01/2006 and 12/1/2018. The maximum and mean SUV, and the ratio of the maximum SUV to mean blood pool were calculated. Pearson’s correlations between lesion size and maximum SUV were calculated. RESULTS The ranges of the maximum SUV were as follows: For hemangiomas (0.95-2.99), bone infarcts (0.37-3.44), bone islands (0.26-3.29), enchondromas (0.46-2.69), fibrous dysplasia (0.78-18.63), osteochondromas (1.11-2.56), Paget’s disease of bone (0.93-5.65), insufficiency fractures (1.06-12.97) and for osteomyelitis (2.57- 12.64). The range of the maximum SUV was lowest for osteochondromas (maximum SUV 2.56) and was highest for fibrous dysplasia (maximum SUV of 18.63). There was at least one lesion that demonstrated greater 18F-FDG avidity than the blood pool amongst each lesion type, with the highest maximum SUV ranging from 9.34 times blood pool mean (osteomyelitis) to 1.42 times blood pool mean (hemangiomas). There was no correlation between the maximum SUV and the lesion size except for enchondromas. Larger enchondromas had higher maximum SUV (r = 0.36, P = 0.02). CONCLUSION The classic “do not touch” lesions and classic benign lesions can be 18F-FDG avid. The CT appearance of these lesions should dictate clinical management rather than the maximum SUV.
文摘Iris du Pré, a professional pianist, wanted a second child, did not conceive quickly and was injected in 1944 by a doctor in Oxford with pregnant mare serum gonadotropin (PMSG). The doctor joked “This child will be a racehorse winner!” In January 1945, Jacqueline du Pré, the remarkable, world-famous cellist was born. In the 1920's and 1930's, animal experimentation and clinical studies had shown that pituitary glycoproteins stimulated the ovary (follicle-stimulating hormone, FSH) and the corpus luteum (luteal-stimulating hormone, LH) which prepared the human womb for embedding a fertilized ovum and that pregnant mare’s blood and urine contained the glycoprotein, PMSG whose origin was placental cells, but surprisingly in humans had the actions of both FSH and LH. However, the PMSG serum alone did not bring about pregnancy. The doctor did not know that without subsequent injection of another factor in correct sequence and timing, PMSG was pointless. In 1947, a placental glycoprotein, found in the 1920's in urine of pregnant women (human chorionic gonadotropin, hCG), when injected in mice subsequent to PMSG, achieved ovulation but not pregnancy. Human application of those findings was extremely risky due to impurities (up to 95%). The Federal Drug Administration (FDA), established in 1938, requested easily bye-passed marketing safety. Companies offered material “sufficiently” purified;professional bodies negated clinical use, tempting to a few. Evidence also suggests that, to sustain pregnancy the doctor also prescribed the new “eostrogen”, diethyl stilbestrol (DES) of negative fame. In 1947, the Nuremberg Code of ethics demanded human experiments by qualified personnel and trials preceded by adequate animal studies. It is not the case here. From five, du Pré had a most exceptional musical memory, almost obsessive musicality and a very difficult school-time socially. Later history: adult masculine build, awkward gait, tendency to recurrent depressions from mid-adolescence, unbalanced thyroidal metabolism, symptoms of numbness in late teens, long breaks for rest from age 25, MS diagnosis at 28 when unable to play, death aged 42. Yet at sixteen and after, she astounded all with technique, passion and unique musical interpretation. Her husband, an outstanding musician: “She had a capacity to imagine sound such as I never met in any other musician”. A close musician colleague: “... it was done before she was born”;perhaps much closer to the truth than realization, for her history it may suggest a fetal neurodevelopment abused in the womb.
文摘本文从目前对"do you think"做插入语的普遍认识着手,用乔姆斯基的最简方案理论解释并阐明"do you think"句的生成过程,澄清"do you think"非但不是插入语,还是很重要的句子成分。并进一步讨论了"do you think"和"do you know"两个看似相似的句型为何在使用上会存在很大的差别。也希望由此引起学者们对功能语言学与形式语言学在解释实际问题上存在的分歧给予更多讨论,关注英语教学中的一些解释性错误。
