High altitude hypoxia and chemodectomas

Twenty-three of 25 Peruvian adults with chemodectomas of the head and neck had been born and lived at altitudes between 2105 and 4350 meters (6904 to 14,268 feet). Estimates of prevalence in Peru indicate that chemodectomas are about 10 times more frequent at high altitudes than at sea level.All carotid body tumors in the high altitude patients were benign; one other patient had a malignant glomus jugulare tumor. Females predominated over males in the proportion of 6.33:1 and left sided carotid body tumors over right sided in a ratio of 3.20:1. In only one instance was the carotid body tumor bilateral. One-half of the high altitude patients with carotid body tumors also had significant respiratory abnormalities.The present observations suggest that carotid body tumors in the high altitude native represent the extreme degree of hyperplastic response of chemoreceptor tissue to prolonged and severe hypoxia.     

Bulimia: Prevalence Estimates in Female Junior High and High School Students

Examined the prevalence of bulimia in female junior high and high school students residing in an agricultural community within a large, rural catchment area. We conducted follow-up interviews with subgroups of clinical and control participants screened for bulimia by self-report measures. Corroborating interview data showed that the overall prevalence of bulimia was greater than 1.7%. Sole reliance on established cutoff scores from the Bulimia Test suggests estimates of about 2 % for female junior high school students and 4% for female high school students. Although bulimia appears to be somewhat more common in high school, few differences between female junior high and high school students were found in the prevalence of extreme dieting behaviors (e.g., self-induced vomiting).     

High altitude and oxidative stress

Exposure to high altitude, which is associated with decreased oxygen pressure, could result in oxidative/reductive stress, enhanced generation of reactive oxygen and nitrogen species (RONS), and related oxidative damage to lipids, proteins, and DNA. The severity of oxidative challenge is related to the degree of altitude. A wide range of RONS generating systems are activated during exposure to high altitude, including the mitochondrial electron transport chain, xanthine oxidase, and nitric oxide synthase. High altitude appears to weaken the enzymatic and non-enzymatic antioxidant systems, and increased nutritional uptake of antioxidant vitamins are beneficial to reduce the altitude-induced oxidative damage. The pattern of high altitude exposure-associated oxidative damage resembles ischemia/reperfusion injury. The adaptive process to this oxidative challenge requires a relatively long period of time. Physical exercise or an enhanced level of physical activity at high altitude, exacerbates the extent of the oxidative challenge. Therefore, special attention is necessary to curb the degree of oxidative stress.     

A Flexible and High Speed Digital Scan Converter for High Frequency Ultrasound Imaging

This paper presents a flexible and high speed digital scan converter (DSC) with the ability to handle high frequency ultrasound imaging in real-time. The characteristics in imaging system such as focus length of transducer, the swing radius and sampling length etc. could be changed easily in compliance with the researcher’s application based on this flexible digital scan converter. Linear interpolation is employed to achieve the coordinate transformations algorithm. Custom-built software is programmed to preliminarily handle the algorithm according to different ultrasound imaging applications. High performance FPGA will implement high speed interpolation calculation based on the preliminary data which are stored in the DDR2 SDRAM from the software. 64 bit 66 MHz PCI is employed to accomplish high speed data transmission. Experiment has shown that more than 500 frame rate could be achieved based on this high speed digital scan converter. The designed flexible and high speed digital scan converter could be used in current FPGA based high frequency ultrasound imaging system.     

High altitude and hypertension during pregnancy

Hypertensive complications of pregnancy are more common at high than low altitudes. Hypertension in pregnancy is associated with increased maternal and fetal morbidity and mortality; thus natural selection may be operating against women who develop the disorder and their infants. It has long been hypothesized that chronic hypoxia due to residence at high altitude predisposes women to develop hypertension during pregnancy. Prior studies indicate that maternal adaptation to pregnancy is altered by residence at high altitude such that some physiological characteristics of women pregnant at high altitude resemble those of women who develop hypertension during pregnancy at low altitude. This paper reviews data from studies, conducted over the past decade, which support a relationship between chronic hypoxia and hypertension during pregnancy. The results suggest that both the requirements for successful adaptation to high altitude, as well as the effect of lowered P_O2 during pregnancy, may contribute to the development of hypertension during pregnancy. © 1995 Wiley-Liss, Inc.     

High carbohydrate diets and Alzheimer's disease

Alzheimer's disease (AD) is a common, progressive, neurodegenerative disease that primarily afflicts the elderly. A well-defined risk factor for late onset AD is possession of one or more alleles of the epsilon-4 variant (E4) of the apolipoprotein E gene. Meta-analysis of allele frequencies has found that E4 is rare in populations with long historical exposure to agriculture, suggesting that consumption of a high carbohydrate (HC) diet may have selected against E4 carriers. The apoE4 protein alters lipid metabolism in a manner similar to a HC diet, suggesting a common mechanism for the etiology of AD. Evolutionarily discordant HC diets are proposed to be the primary cause of AD by two general mechanisms. (1) Disturbances in lipid metabolism within the central nervous system inhibits the function of membrane proteins such as glucose transporters and the amyloid precursor protein. (2) Prolonged excessive insulin/IGF signaling accelerates cellular damage in cerebral neurons. These two factors ultimately lead to the clinical and pathological course of AD. This hypothesis also suggests several preventative and treatment strategies. A change in diet emphasizing decreasing dietary carbohydrates and increasing essential fatty acids (EFA) may effectively prevent AD. Interventions that restore lipid homeostasis may treat the disease, including drugs that increase fatty acid metabolism, EFA repletion therapy, and ketone body treatment.     

高盐摄入与骨代谢

Osteoporosis has become a global public health problem, and dietary interventions may potentially be helpful in preventing this disorder. Salt (sodium chloride) is one of the most important dietary nutrients. High sodium chloride intake may play an important role in bone metabolism. In this paper, we reviewed the effects of high sodium chloride intake on bone mineral density, bone mineral content and bone biochemical markers, and analyzed the possible causes through currently available literature. Although there are a few inconsistencies results, we conclude a long-term high salt intake can reduce bone density or bone mineral content, change many biochemical markers of bone resorption, which may be caused mainly by increasing urinary calcium excretion and a low-grade metabolic acidosis. However, there are still many unclear aspects need further exploration.     

Generalist Genes and High Cognitive Abilities

The concept of generalist genes operating across diverse domains of cognitive abilities is now widely accepted. Much less is known about the etiology of the high extreme of performance. Is there more specialization at the high extreme? Using a representative sample of 4,000 12-year-old twin pairs from the UK Twins Early Development Study, we investigated the genetic and environmental overlap between web-based tests of general cognitive ability, reading, mathematics and language performance for the top 15% of the distribution using DF extremes analysis. Generalist genes are just as evident at the high extremes of performance as they are for the entire distribution of abilities and for cognitive disabilities. However, a smaller proportion of the phenotypic intercorrelations appears to be explained by genetic influences for high abilities.     

关于中学生烦恼的调查

目的：对当前中学生的烦恼状况及造成烦恼的主要因素作调查。方法：通过开放式、自编问卷，对山西省593名中学生进行测查。结果：发现(1)中学生普遍感到烦恼，而在对自己的形象、父母的管教、学业压力、个性发展和人际交往方面的烦恼较为明显；(2)最烦恼的问题是“被朋友出卖”、“学习效率不高”、“被老师讽刺挖苦”等；(3)在个人外貌和个性发展方面，初中生与高中生的烦恼程度存在显著差异。结论：家庭、学校和社会应当给予中学生足够的关注，减少造成中学生烦恼的负性事件；同时，提高学生的认知能力和对事物的评价能力。     

High cost patients and the consortium approach

The Pan-Thames Haemophilia Consortium was established to provide coherent regional planning of haemophilia services. The Expert Advisory Group is a clinical reference point for the consortium and was established to consider specifically elective high cost treatment programmes. An audit of the first year of consortium activity demonstrated that patients receiving high cost therapy represented 1.6% of the patient population and received 16% of the entire treatment budget. The Pan-Thames Consortium provides focused commissioning expertise and a model for national commissioning of haemophilia services.     

高位挂线加低位脱细胞真皮基质填塞治疗高位复杂性肛瘘

目的 探究高位挂线加低位脱细胞真皮基质（AEM）填塞治疗高位复杂性肛瘘。方法 选取于2017年3月~2018年3月安徽医科大学附属合肥市第二人民医院收治的56例高位复杂性肛瘘患者作为研究对象,随机分为治疗组和对照组,每组28例。治疗组给予AEM治疗,对照组给予以传统瘘管切开挂线术治疗,比较两组患者的治疗效果、治愈率及复发率。结果 治疗组的疼痛持续时间、伤口愈合时间均短于对照组（P＜0.05）;其术后并发症总发生率及复发率分别为3.57%和0,均低于对照组的39.28%和7.14%,差异有统计学意义（P＜0.05）;治疗组治愈率为85.71%,高于对照组的71.43%,差异有统计学意义（P＜0.05）。结论 对高位复杂性肛瘘患者采取高位挂线加低位脱细胞真皮基质填塞治疗疗程短,治愈率高,复发率低,临床治疗上具有一定的优势。     

High resolution EEG

My research is supported by competitive grants from The National Institute of Mental Health, The National Institute of Neurological Diseases and Strokes, The Air Force Office of Scientific Research, The Office of Naval Research, The National Science Foundation and The National Institute of Alcoholism and Alcohol Abuse of the United States Federal government. I thank all my colleagues at EEG Systems Laboratory and SAM Technology for their essential contributions to our research, including especially, Jim Alexander, Jeffrey Bennett, Brian Cutillo, John Desmond, Don DuRousseau, Paul Hubenig, Judy McLaughlin, Jim Johnston, Jian Le, Harrison Leong, Nancy Martin, Vinod Menon, Bill O'Connor, Maggie Paula, Paulo Raffaelli, Bryan Reutter, Lita Sam Vargas, Michael Smith, Mike Ward, Jenny Zhang, and Jane Zhu. Thanks also to KDS.     

High technologies in radiodiagnostics: possibilities and prospects

Diagnostic radiology includes several basic techniques such as conventional radiography, computed tomography, magnetic resonance imaging, radionuclide study, ultrasonography, and positron emission tomography as the most important methods. Radiological screening procedures or preclinical diagnostic techniques, as well as interventional radiological procedures, are being used more and more widely in clinical medicine. The integration and combination of different technologies, the introduction of digital diagnostic technologies, and the creation of radiological information systems on their basis are important factors increasing diagnostic efficiency. Improved technologies make it possible to change diagnostic tactics in the majority of diseases; the diagnostic process shortens because preference is given to most informative methods. Intensive technological development requires changes in the arrangement of radiologists' work.