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Hepatic Morphometric Correlation with Biophysical Profiling of Height
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作者 Precious Belema Ibiabuo 《Journal of Biosciences and Medicines》 2024年第7期194-206,共13页
Introduction: Clinical assessment of hepatic span is usually subjective. And is based on the experience of the clinician. This is what has led to this study in using Biophysical profiling of Heights, Weights, and Body... Introduction: Clinical assessment of hepatic span is usually subjective. And is based on the experience of the clinician. This is what has led to this study in using Biophysical profiling of Heights, Weights, and Body mass index to find the normal hepatic span of every individual. This study was conducted at HMG Hospital Limited, Abonnema in Rivers State in affiliation with the University of Port Harcourt. Methodology: The biophysical sampling method was instituted to select respondents. At the same time, a radiological formula was used to calculate the sample size, and subjects’ weight, height and hepatic span where measured while the BMI was calculated and the data was analyzed using python programming language for data science. Results: The data obtained were subjected to descriptive statistics and the Pearson correlation coefficient. P value greater than or equal to 0.05 was taken as statistically significant. The respondents were mainly aged 30 to 63 years. Conclusion: The null hypothesis was rejected;hence this research has stated the law known as Belema’s Law of hepatic-height correlation, which states that the hepatic span of an individual is directly proportional to the height of that individual except in disease conditions affecting the liver directly or indirectly. 展开更多
关键词 Hepatic Span height body Mass Index Weight
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The Influence of Secular Trends in Body Height and Weight on the Prevalence of Overweight and Obesity among Chinese Children and Adolescents 被引量:3
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作者 FU Lian Guo SUN Li Li +6 位作者 WU Shao Wei YANG Yi De LI Xiao Hui WANG Zheng He WU Lu WANG Fu Zhi MA Jun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第12期849-857,共9页
Objective To explore the influence of secular trends in body height and weight on the prevalence of overweight and obesity among Chinese children and adolescents. Methods The data were obtained from five cross-section... Objective To explore the influence of secular trends in body height and weight on the prevalence of overweight and obesity among Chinese children and adolescents. Methods The data were obtained from five cross-sectional Chinese National Surveys on Students' Constitution and Health. Overweight/obesity was defined as BMI-for-age Z-score of per the Wold Health Organization (WHO) reference values. Body height and weight for each sex and age were standardized to those reported in 1985 (standardized height" SHY, standardized weight: SWY) and for each sex and year at age 7 (standardized height: SHA; standardized weight: SWA) using the Z-score method. Results The prevalence of overweight/obesity in Chinese children was 20.2% among boys and 10.7% among girls in 2010 and increased continuously from 1985 to 2010. Among boys and girls of normal weight, SHY and SHA were significantly greater than SWY and SWA, respectively (P 〈 0.001). Among boys and girls with overweight/obesity, SHY was significantly lower than SWY (P 〈 0.001), and showed an obvious decreasing trend after age 12. SHA was lower than SWA among overweight boys aged 7-8 years and girls aged 7-9 years. SHY/SHW and SHA/SWA among normal-weight groups were greater than among overweight and obese groups (P 〈 0.001). Conclusion The continuous increase in the prevalence of overweight/obesity among Chinese children may be related to a rapid increase in body weight before age 9 and lack of secular increase in body height after age 12. 展开更多
关键词 OBESITY CHILDREN Secular trends body height body weight
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Investigation of blood pulse PPG signal regulation on toe effect of body posture and lower limb height 被引量:2
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作者 XIN Shang-zhi HU Sijung +4 位作者 CRABTREE Vincent P. ZHENG Jia AZORIN-PERIS Vincent ECHIADIS Angelos SMITH Peter R. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期916-920,共5页
Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-inv... Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position. 展开更多
关键词 Photoplethysmographv (PPG) NON-INVASIVE body posture Blood pulse volume signal lower limb
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The Rise and Fall of the Secular Trend in Body Height in Sardinia:An Age-Period-Cohort Analysis
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作者 Giovanni Mario PES Roberta SALIS +5 位作者 Alessandra ERRIGO Marco SATURNO Stefano BIBBO’ Bianca Maria QUARTA COLOSSO Nunzio Pio LONGO Maria Pina DORE 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第3期183-190,共8页
Objective Over the last century, a progressive rise in stature, known as the ‘secular trend’, was documented worldwide, and especially in Sardinia, it has reached a peak in Europe. However, this situation recently c... Objective Over the last century, a progressive rise in stature, known as the ‘secular trend’, was documented worldwide, and especially in Sardinia, it has reached a peak in Europe. However, this situation recently ceased in several populations. In this study, we tested the hypothesis that the stature secular trend has significantly leveled off in the Sardinian younger generations.Methods Height measurements were retrieved from a database of patients undergoing digestive endoscopy, spanning generations between 1920 and 1990. Sex-specific principal component regression models were fitted to decompose stature variation into the contribution of age, period, and birth cohort.Results A steady increase in stature was observed in generations born after 1920, with an upward surge in those born after 1950. However, a significant leveling off was observed among cohorts born after 1970 among both sexes, as mean heights stabilized at 171.1 cm with a standard error(SE) of 0.9 cm among men and a mean of 160.1 cm(SE = 0.9 cm) among women.Conclusion Our findings support a significant slowdown in the secular trend of stature among the latest Sardinian generations. Several factors, including the consumption of low-quality food, lack of physical activity, and late motherhood, among others, may explain the decline in the secular trend. 展开更多
关键词 body height Secular trend Socioeconomic status SARDINIA
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Estimate of the lower-limb-specific muscle parameters during bipedal walking for humans,apes and early hominids with the implications for the evolution of body proportion
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作者 WangWeijie 《仪器仪表学报》 EI CAS CSCD 北大核心 2007年第8期1358-1366,共9页
Modern human has different body proportion from early hominids and great apes.Comparing with others,in general,modern human adults have relatively long lower limb and heavier body weight.Since the lower limbs provide ... Modern human has different body proportion from early hominids and great apes.Comparing with others,in general,modern human adults have relatively long lower limb and heavier body weight.Since the lower limbs provide support to the whole body and play an important role in walking,it is proposed that the ratio of the lower limb to the whole body for modern human could be beneficial to bipedal walking.This study tried to estimate the muscle parameters of the lower limb in walking for the subjects with various body proportions.Using a simplified musculoskeletal model,some muscle parameters of the lower limb,e.g.muscle force,stress,work and power,were estimated for modern human adult,child,AL 288-1(the fossil specimens of Australopithecus afarensis,3.18 million years old)and apes.The results show that with the body proportion modern human adult spends less muscle work and power in walking than other subjects.The results imply that using the cost of transport(i.e.the muscle work of the lower limb per unit of displacement)as the criteria,the early hominids,if their body proportions were structurally similar to AL 288-1,could evolve towards what modern human adult looks like,in order to save energy during bipedal walking. 展开更多
关键词 人类 进化 原始人类 直立行走 下肢 肌肉 工作参数 压力
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Decoding RoPax Ship Capsizes and Development of an ISO Ship Safety Standard
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作者 Soonhung Han Robert Latorre 《Engineering(科研)》 2024年第9期225-236,共12页
Marine accidents often result in significant losses of human life, environmental damage, and property destruction. Additionally, ships and offshore plants are large-scale and complex systems, making safety assessments... Marine accidents often result in significant losses of human life, environmental damage, and property destruction. Additionally, ships and offshore plants are large-scale and complex systems, making safety assessments challenging. However, the advent of onboard electronic systems has made it possible to monitor and respond more effectively. These new technologies can enhance safety levels while reducing the workload on crews. In this paper, authors analyze recent accidents involving ships with high structures above the water, such as car carriers or RoPax vessels, and propose preventive safety indicators to help prevent similar accidents from recurring. 展开更多
关键词 Ship Accident CAPSIZE RoPax Ship Profile height Regulatory body ISO Standards
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Hierarchical Control of Ride Height System for Electronically Controlled Air Suspension Based on Variable Structure and Fuzzy Control Theory 被引量:14
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作者 XU Xing ZHOU Kongkang +2 位作者 ZOU Nannan JIANG Hong CUI Xiaoli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期945-953,共9页
The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjust... The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjustment during different driving conditions. However, the nonlinearity of the ride height adjusting system and the uneven distribution of payload affect the control accuracy of ride height and the body attitude. Firstly, the three-point measurement system of three height sensors is used to establish the mathematical model of the ride height adjusting system. The decentralized control of ride height and the centralized control of body attitude are presented to design the ride height control system for ECAS. The exact feedback linearization method is adopted for the nonlinear mathematical model of the ride height system. Secondly, according to the hierarchical control theory, the variable structure control (VSC) technique is used to design a controller that is able to adjust the ride height for the quarter-vehicle anywhere, and each quarter-vehicle height control system is independent. Meanwhile, the three-point height signals obtained by three height sensors are tracked to calculate the body pitch and roll attitude over time, and then by calculating the deviation of pitch and roll and its rates, the height control correction is reassigned based on the fuzzy algorithm. Finally, to verify the effectiveness and performance of the proposed combined control strategy, a validating test of ride height control system with and without road disturbance is carried out. Testing results show that the height adjusting time of both lifting and lowering is over 5 s, and the pitch angle and the roll angle of body attitude are less than 0.15°. This research proposes a hierarchical control method that can guarantee the attitude stability, as well as satisfy the ride height tracking system. 展开更多
关键词 electronically controlled air suspension (ECAS) ride height body attitude hierarchical control
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Vitality variation and population structure of a riparian forest in the lower reaches of the Tarim River,NW China 被引量:8
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作者 Maierdang Keyimu Umut Halik +1 位作者 Florian Betz Choimaa Dulamsuren 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第3期742-753,共12页
Since 2000, the Chinese government has implemented emergency water diversion measures to restore the damaged riparian forest ecosystem with dominant tree species Euphrat poplar(Populus euphratica Oliv.)at the lower re... Since 2000, the Chinese government has implemented emergency water diversion measures to restore the damaged riparian forest ecosystem with dominant tree species Euphrat poplar(Populus euphratica Oliv.)at the lower reaches of the Tarim River. In the present study, comparative analysis of variations in the vitality of P. euphratica trees were made using 2005 and 2010 data to illustrate the revitalization process of riparian forest. Poplar trees within 300 m of the riverbed were positively revitalized, while the vitality of trees farther than 300 m from the river decreased. Population structure was studied to demonstrate the development of poplar community. In the first belt, the class structure for the diameter at breast height(DBH) of P. euphratica fit a logistic model, and the 2nd, 3rd and 4th belt curve fittings were close to a Gaussian model; in other plots they were bimodal. Cluster analysis of the composition of the DBH class of poplar trees demonstrated that those within 16–36 cm DBH were the most abundant(58.49% of total) in study area, under 16 cm of DBH were second(31.36%), and trees >40 cm DBH were the least abundant(10.15%). More than 80% of the trees were young and medium-sized, which means that the poplar forest community in the vicinity of the lower Tarim River is at a stable developmental stage. The abundance of juvenile trees of P. euphratica in the first and second measuring belts was 12.13% in 2005 and increased to 25.52% in 2010, which means that the emergency water transfer had a positive impact on the generation of young P. euphratica trees in the vicinity of the river. 展开更多
关键词 lower Tarim River Riparian forest ecosystem Populus euphratica VITALITY Population structure Diameter at breast height
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Dynamic biomechanical effect of lower body positive pressure treadmill training for hemiplegic gait rehabilitation after stroke: A case report 被引量:3
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作者 Hui-Fang Tang Bing Yang +2 位作者 Qiang Lin Jun-Jie Liang Zhi-Wei Mou 《World Journal of Clinical Cases》 SCIE 2021年第3期632-638,共7页
BACKGROUND Lower body positive pressure(LBPP)treadmill has potential applications for improving the gait of patients after stroke,but the related mechanism remains unclear.CASE SUMMARY A 62-year-old male patient suffe... BACKGROUND Lower body positive pressure(LBPP)treadmill has potential applications for improving the gait of patients after stroke,but the related mechanism remains unclear.CASE SUMMARY A 62-year-old male patient suffered from ischemic stroke with hemiplegic gait.He was referred to our hospital because of a complaint of left limb weakness for 2 years.The LBPP training was performed one session per day and six times per week for 2 wk.The dynamic plantar pressure analysis was taken every 2 d.Meanwhile,three-digital gait analysis and synchronous electromyography as well as clinical assessments were taken before and after LBPP intervention and at the 4-wk follow-up.During LBPP training,our patient not only improved his lower limb muscle strength and walking speed,but more importantly,the symmetry index of various biomechanical indicators improved.Moreover,the patient’s planter pressure transferring from the heel area to toe area among the LBPP training process and the symmetry of lower body biomechanical parameters improved.CONCLUSION In this study,we documented a dynamic improvement of gait performance in a stroke patient under LBPP training,which included lower limb muscle strength,walking speed,and symmetry of lower limb biomechanics.Our study provides some crucial clues about the potential dynamic mechanism for LBPP training on gait and balance improvement,which is related to rebuilding foot pressure distribution and remodeling symmetry of biomechanics of the lower limb. 展开更多
关键词 lower body positive pressure treadmill Dynamic plantar pressure STROKE Gait analysis Electromyography Case report REHABILITATION
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Effects of lower body positive pressure treadmill on functional improvement in knee osteoarthritis:A randomized clinical trial study 被引量:2
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作者 Hong-Xin Chen Yao-Xuan Zhan +7 位作者 Hai-Ning Ou Yao-Yao You Wan-Ying Li Shan-Shan Jiang Mei-Feng Zheng Lin-Zi Zhang Ke Chen Qiu-Xia Chen 《World Journal of Clinical Cases》 SCIE 2021年第34期10604-10615,共12页
BACKGROUND Knee joint pain and stiffness are the two main symptoms of knee osteoarthritis(OA)and thus restrict a patient’s activities,such as walking and walking up and downstairs.The lower body positive pressure(LBP... BACKGROUND Knee joint pain and stiffness are the two main symptoms of knee osteoarthritis(OA)and thus restrict a patient’s activities,such as walking and walking up and downstairs.The lower body positive pressure(LBPP)treadmill as one of the emerging body weight support system devices brings new hope for exerciserelated rehabilitation for knee OA patients.AIM To investigate the biomechanical effects and the subjective clinical assessment of LBPP treadmill walking exercise when compared with conventional therapy in mild to moderate knee OA patients.METHODS Eighteen patients with mild-to-moderate knee OA were recruited in this randomized controlled trial(RCT)study.The eligible knee OA patients were randomly assigned to two groups:LBPP and control groups.The patients in the LBPP group performed an LBPP walking training program for 30 min/session per day,6 d per week for 2 wk whereas the patients in the control group performed walking on the ground for the same amount.All patients underwent clinical assessments and three-dimensional gait analysis at pre-and 2-wk post-treatment.RESULTS The Western Ontario and McMaster Universities Arthritis Index and visual analog scale scores in both the LBPP group and control group were found to decrease significantly at the post-treatment point than the pre-treatment point(LBPP:70.25±13.93 vs 40.50±11.86;3.88±0.99 vs 1.63±0.52;control:69.20±8.88 vs 48.10±8.67;3.80±0.79 vs 2.60±0.70,P<0.001).Moreover,compared with the control group,the LBPP group showed more improvements in walking speed(P=0.007),stride length(P=0.037),and knee range of motion(P=0.048)during walking,which represented more improvement in walking ability.CONCLUSION The results of our RCT study showed that the LBPP group has a greater effect on improving gait parameters than the conventional group,although there was no significant advantage in clinical assessment.This finding indicates that LBPP treadmill walking training might be an effective approach for alleviating pain symptoms and improving lower extremity locomotion in mild to moderate knee OA patients. 展开更多
关键词 lower body positive pressure Three-dimensional gait analysis Walking training REHABILITATION Knee osteoarthritis
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Exact Statistical Distribution of the Body Mass Index (BMI): Analysis and Experimental Confirmation 被引量:1
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作者 Mark P. Silverman Trevor C. Lipscombe 《Open Journal of Statistics》 2022年第3期324-356,共33页
Body Mass Index (BMI), defined as the ratio of individual mass (in kilograms) to the square of the associated height (in meters), is one of the most widely discussed and utilized risk factors in medicine and public he... Body Mass Index (BMI), defined as the ratio of individual mass (in kilograms) to the square of the associated height (in meters), is one of the most widely discussed and utilized risk factors in medicine and public health, given the increasing obesity worldwide and its relation to metabolic disease. Statistically, BMI is a composite random variable, since human weight (converted to mass) and height are themselves random variables. Much effort over the years has gone into attempts to model or approximate the BMI distribution function. This paper derives the mathematically exact BMI probability density function (PDF), as well as the exact bivariate PDF for human weight and height. Taken together, weight and height are shown to be correlated bivariate lognormal variables whose marginal distributions are each lognormal in form. The mean and variance of each marginal distribution, together with the linear correlation coefficient of the two distributions, provide 5 nonadjustable parameters for a given population that uniquely determine the corresponding BMI distribution, which is also shown to be lognormal in form. The theoretical analysis is tested experimentally by gender against a large anthropometric data base, and found to predict with near perfection the profile of the empirical BMI distribution and, to great accuracy, individual statistics including mean, variance, skewness, kurtosis, and correlation. Beyond solving a longstanding statistical problem, the significance of these findings is that, with knowledge of the exact BMI distribution functions for diverse populations, medical and public health professionals can then make better informed statistical inferences regarding BMI and public health policies to reduce obesity. 展开更多
关键词 body Mass Index OBESITY Distribution of Weight Distribution of height Correlation of Weight and height
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Evaluation of global cardiac systolic performance and diastolic filling in central hypovolumia by lower body negative pressure with Doppler echocardiography
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作者 Baomin Liu Xiaolin Niu +3 位作者 Benyu Jiang Mike Seddon Keren McNeil Philip Chowienczyk 《Journal of Nanjing Medical University》 2007年第4期227-232,共6页
Objective :To overall evaluate the change of global cardiac systolic performance and diastolic filling in hypovoleamia by LBNP, Methods:10 healthy male subjects were placed in a standard LBNP chamber. Baseline haemo... Objective :To overall evaluate the change of global cardiac systolic performance and diastolic filling in hypovoleamia by LBNP, Methods:10 healthy male subjects were placed in a standard LBNP chamber. Baseline haemodynamic and echocardiographic measurements were made after a period of least 10 min resting supine within the chamber. Pressure was then decreased to -10,-20 and -30 mmHg, with each pressure maintained for 15 rain. The indices of four transvalvular and SVC flow were measured using Doppler echocardiography. Results :The results showed that S wave, Re wave ,and VTI of SVC progressively decreased with increasing LBNP. At -30 mmHg stage, S wave decreased by 35.4 % (change of 0.21±0.03 m/s, P 〈 0.001). This reduction in pre-load Was associated with a progressive decrease in SV(by 21.5 ± 4.5 ml at -30 mmHg,P 〈 0.001 ), decrease in CO(by 1.2 ± 0.2 L min^-1 at -30 mmHg LBNP,P 〈 0.001 ). The diastolic filling of mitral and tricuspid flow also reduced significantly. At -30 mmHg stage, the E wave of MVF and TVF decreased 31% and 32% respectively (change of 0.23 ± 0.05 m/s,P 〈 0.001 and 0.18 ± 0.01 m/s,P 〈 0.001). VTI of MVF and TVF decreased 27% and 27.7% respectively(change of 5.55 ± 1.41cm,P 〈 0.01 and 4.25 ± 0.44 cm,P 〈 0.01). A wave of both sides did not change significantly. Conclusion:Doppler indices changes in different LBNP stage can roughly reflect the degree of hypovoleamia caused by blood volume redistribution. The indices of Doppler echocardiography are more sensitive than traditional physiological indexes in evaluating cardiovascular responses of LBNP. Echocardiography techniques overall can evaluate the global cardiac function including systolic performance and diastolic filling. 展开更多
关键词 function HEART ECHOCARDIOGRAPHY lower body negative pressure
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Application of cerebral-myocardial perfusion combined with lower body circulatory arrest in pediatric complex aortic arch surgery
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作者 Yuanyuan Tong Jinping Liu +1 位作者 Ruoning Lv Yu Jin 《中国循环杂志》 CSCD 北大核心 2018年第S01期171-171,共1页
Background Adjunct RCP to DHCA ensures some extent uninterrupted cerebral perfusion and that promotes one-stage repair of complex aortic arch anomaly.One-stage repair may induce longer myocardial ischemic time.So ther... Background Adjunct RCP to DHCA ensures some extent uninterrupted cerebral perfusion and that promotes one-stage repair of complex aortic arch anomaly.One-stage repair may induce longer myocardial ischemic time.So there evolved cerebral-myocardial perfusion to reduce myocardial ischemic time.Methods We reviewed 78 patients from January 2010 to July 2017 in our center. 展开更多
关键词 lower body circulatory ARREST PEDIATRIC COMPLEX aortic arch surgery DHCA
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A Therapeutic Concept by “Watted” for the Surgical Lengthening of the Lower Face by Short Face Syndrome
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作者 Nezar Watted Abu-Hussein Muhamad +1 位作者 Josip Bill Peter Proff 《Open Journal of Stomatology》 2015年第5期127-141,共15页
The continuously growing esthetic awareness for the facial appearance and the spreading of information about the possibilities of adult treatment by public media result in an increase of adult patients which seek orth... The continuously growing esthetic awareness for the facial appearance and the spreading of information about the possibilities of adult treatment by public media result in an increase of adult patients which seek orthodontic treatment to improve their facial esthetics. In general, these patients show such a severe skeletal deformity that it is detectable even by non-experts because of its extraoral manifestation, which is the main motivation for treatment. Because of the nature of these deformities and because of the lacking growth usable for therapy the only promising treatment for these patients is the combined orthodontic-surgical approach. Besides a stable and functional occlusion with physiologic position of the condyle, the goals of treatment are the improvement of the dental and, above all, facial esthetics since the patient judges the success of treatment mostly by the extraoral appearance. The dentofacial appearance must be defined prior to treatment to plan the individual right approach in knowledge of the different treatment possibilities for Angle Class II deformities and thus be able to reach for both sides—patient and orthodontist—satisfying result. With this article, a systematic therapy concept to treat patients with Class II deformities and skeletal deep bite with a short lower face (short face syndrome) under consideration of the soft tissue analysis is presented. 展开更多
关键词 Cephalometrics Facial Proportions lower FACE height Skeletal Deep BITE SHORT FACE SYNDROME LENGtheNING of the lower FACE Bilateral Sagittal Split Osteotomy Mandibular Advancement Splint therapy Lateral Open BITE
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Experimental test and theoretical calculation of the fracture height limit of gas pipe flow to Darcy flow
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作者 XIONG Yu FU Xitong +3 位作者 LI Qian SUN Zewei ZHANG Chun ZHANG Fei 《Petroleum Exploration and Development》 CSCD 2022年第3期614-624,共11页
Low-speed flow experiments in which ultra-fine copper tubes are used to simulate micro-fractures in carbonate strata are conducted to analyze the variations of gas flow state in fractures of different fracture heights... Low-speed flow experiments in which ultra-fine copper tubes are used to simulate micro-fractures in carbonate strata are conducted to analyze the variations of gas flow state in fractures of different fracture heights,determine flow state transition limit and transition interval,and establish the calculation method of flow state transition limit.The results show that the ideal Hagen-Poiseuille flow is the main form of gas flow in large fractures.Due to the decrease of fracture height,the gas flow in the fracture changes from Hagen-Poiseuille flow with ideal smooth seam surface to non-Hagen-Poiseuille flow,and the critical point of the transition is the boundary of flow state transition.After the fracture height continues to decrease to a certain extent below the boundary of the flow state transition fracture height,the form of gas flow gradually changes to the ideal Darcy flow,thus the transition interval of the gas flow state in the closing process of fracture can be determined.Based on the three-dimensional microconvex body scanning of the fracture surface,the material properties of fracture and properties of fluid in the fracture,a method for calculating the boundary of flow state transition is established.The experimental test and theoretical calculation show that the limit of the fracture height for the transition from pipe flow to Darcy flow is about twice the sum of the maximum height of the microconvex bodies on the upper and lower sides of the fracture. 展开更多
关键词 carbonate gas reservoir fracture height flow experiment flow limit Hagen-Poiseuille flow Darcy flow microconvex body
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Effects of anti-hypertensive drugs on esophageal body contraction 被引量:5
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作者 Koichi Yoshida Kenji Furuta +7 位作者 Kyoichi Adachi Shunji Ohara Terumi Morita Takashi Tanimura Shuji Nakata Masaharu Miki Kenji Koshino Yoshikazu Kinoshita 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第8期987-991,共5页
AIM:To clarify the effects of anti-hypertensive drugs on esophageal contraction and determine their possi-ble relationship with gastro-esophageal reflux disease.METHODS:Thirteen healthy male volunteers were enrolled. ... AIM:To clarify the effects of anti-hypertensive drugs on esophageal contraction and determine their possi-ble relationship with gastro-esophageal reflux disease.METHODS:Thirteen healthy male volunteers were enrolled. Esophageal body peristaltic contractions and lower esophageal sphincter (LES) pressure were measured using high resolution manometry. All subjects were randomly examined on four separate occasions following administrations of nifedipine,losartan,and atenolol,as well as without any drug administration.RESULTS:Peristaltic contractions by the esophageal body were separated into three segments by two troughs. The peak peristaltic pressures in the mid and lower segments of the esophageal body under atenolol administration were signifi cantly higher than those without medication in a supine position. On the other hand,peristaltic pressures under nifedipine administration were lower than those observed without drug ad-ministration. Losartan did not change esophageal body peristalsis. Atenolol elevated LES pressure and slowed peristaltic wave transition,while the effects of nifedip-ine were the opposite. CONCLUSION:Among the anti-hypertensive drugs tested,atenolol enhanced esophageal motor activity,which was in contrast to nifedipine. 展开更多
关键词 Anti-hypertensive drug High-resolution manometry lower esophageal sphincter Esophageal body contraction Calcium-channel blocker β1 blocker
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Design Guideline of Ultra Thin Body MOSFET
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作者 王文平 黄如 张国艳 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第10期1227-1232,共6页
Simulation method is used to provide a guideline f or ultra thin body(UTB) MOSFET designs.Three important parameters of the UTB MOS FE T,i.e.the raised S/D height,Ge mole fraction of the Ge xSi 1-x gate,and the ... Simulation method is used to provide a guideline f or ultra thin body(UTB) MOSFET designs.Three important parameters of the UTB MOS FE T,i.e.the raised S/D height,Ge mole fraction of the Ge xSi 1-x gate,and the silic on body thickness,are comprehensively analyzed and optimized.The optimal region of feasible Ge mole fraction and the silicon body thickness for low operating po wer device are given.As the simulation results show that through changing Ge mole fraction coupl ed with the silicon body thickness tuning,UTB device with good performance can b e obtained. 展开更多
关键词 ultra thin body MOSFET raised S/D height Ge mole fraction silicon body thicknessEEACC:4250 128 0
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Are age, anthropometry and components of metabolic syndrome-risk factors interrelated with lower urinary tract symptoms in patients with erectile dysfunction? A prospective study 被引量:2
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作者 Jae-Seung Paick Ji-Hyun Yang +1 位作者 Soo-Woong Kim Ja-Hyeon Ku 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第2期213-220,共8页
Aim: To evaluate the effects of metabolic profiles on lower urinary tract symptoms (LUTS) in men with erectile dysfunction (ED). Methods: A total of 75 impotent men aged 25-75 years old (mean 58.1 years) were ... Aim: To evaluate the effects of metabolic profiles on lower urinary tract symptoms (LUTS) in men with erectile dysfunction (ED). Methods: A total of 75 impotent men aged 25-75 years old (mean 58.1 years) were included in the study on a prospective basis. Patients were evaluated with a complete history, physical examination, anthropometry and metabolic profiles. LUTS were assessed using the International Prostate Symptom Score (IPSS). Results: Overall, there was no correlation between the IPSS and continuous parameters. However, when continuous variables were categorized, some parameters were significantly associated with LUTS. Patients with triglyceride level of 150 mg/dL or higher had more severe symptoms than those with tiglyceride levels less than 150 mg/dL (19.4±2.4 vs. 14.3±1.1, P = 0.033). When 40 mg/dL was chosen as the high-density lipoprotein (HDL)-cholesterol cut-off level, the IPSS was significantly different between the two groups divided by 40 mg/dL (19.4±2.6 for HDL-cholesterol 〈 40 mg/dL vs. 14.4±1.0 for HDL-cholesterol 2 40 mg/dL, P = 0.042). The area under the receiver operating characteristic curve (AUROCC) of triglyceride was 65.7% (95% confidence interval [CI], 52.6%-82.3%; P = 0.034) for severe LUTS. However, the AUROCC for 'HDL-cholesterol' was not significant (area, 65.4%; 95% CI, 48.2%-82.7%; P = 0.062). No other factors were determined to be significant in this regard. Conclusion: The results of the present study indicate that some metabolic profiles might influence LUTS in men with ED. 展开更多
关键词 lower urinary tract symptoms erectile dysfunction metabolic syndrome body mass index TESTOSTERONE
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Types, distribution and play targets of Lower Cretaceous tight oil in Jiuquan Basin, NW China 被引量:1
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作者 CHEN Qilin DENG Yilin +5 位作者 WEI Jun MA Guofu LONG Liwen XIAO Wenhua LI Wei ZHANG Liping 《Petroleum Exploration and Development》 2018年第2期227-238,共12页
Based on drilling and laboratory data, the formation conditions of tight oil reservoirs in the Jiuquan basin were comprehensively analyzed and the exploration domains were sorted out. The Jiuquan basin underwent three... Based on drilling and laboratory data, the formation conditions of tight oil reservoirs in the Jiuquan basin were comprehensively analyzed and the exploration domains were sorted out. The Jiuquan basin underwent three cycles of lake level fluctuation in early Cretaceous, leaving three sets of high-quality source rocks, the Zhonggou, Xiagou and Chijinbao Formations in the Lower Cretaceous. There are two types of reservoir assemblages, source-reservoir in one type and source below reservoir type, and two types of tight reservoirs, argillaceous dolomite and conglomerate. The "sweet spots" control the enrichment of oil and gas. Argillaceous dolomite tight oil reservoirs have the characteristic of "integrated source-reservoir", with fractures connecting the matrix micro-pores, pore-fracture type and fracture-pore type "sweet spots" distributed in large scale. The sandy conglomerate tight oil reservoirs were formed by source-reservoir lateral connection, and can be divided into source below reservoir type, source-reservoir side by side type and "sandwich" type. The overlapping areas of the favorable facies belts of fan-delta front and the secondary pore developing belts are the "sweet spot" sites. The favorable areas for seeking conglomerate tight oil are fan-delta front deposits around the Qingxi, Ying'er and Huahai sags, with an exploration area of 550 km^2; while the area to seek argillaceous dolomite tight oil is the NW fracture developed belt in Qingxi sag, with an exploration area of 100 km^2. 展开更多
关键词 TIGHT OIL TIGHT reservoir argillaceous DOLOMITE SANDY CONGLOMERATE body lower CRETACEOUS Jiuquan Basin
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Sedimentary filling characteristics and controlling factors of lacustrine microbial carbonates sequence in the Santos Basin,Brazil 被引量:1
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作者 HE Sai LI Guorong +9 位作者 WU Changrong LIU Shugen ZHANG Zhongmin SU Yushan ZHU Yixuan HE Zhao REN Jie WANG Yuchen ZHOU Wei WANG Yajie 《Petroleum Exploration and Development》 CSCD 2022年第4期785-796,共12页
Based on comprehensive analysis of seismic,logging,core,thin section data,and stable isotopic compositions of carbon and oxygen,the sedimentary filling characteristics of the Lower Cretaceous Barra Velha Formation seq... Based on comprehensive analysis of seismic,logging,core,thin section data,and stable isotopic compositions of carbon and oxygen,the sedimentary filling characteristics of the Lower Cretaceous Barra Velha Formation sequence in H oil field,Santos Basin,are studied,and the high-frequency sequence stratigraphic framework is established,and the spatial distribution of reef-shoal bodies are predicted and the controlling factors are discussed.During the depositional period of the Barra Velha Formation,the study area is a slope-isolated platform-slope sedimentary pattern from southwest to northeast and the change of climate background from rift to depression periods has resulted in the variation of sedimentary characteristics from the lower third-order sequence SQ1(BVE 300 Member)of low-energy deep water to the upper third-order sequence SQ2(BVE 200 and 100 members)of high-energy shallow water in the Barra Velha Formation.The activities of extensional faults and strike-slip faults in rift period and the sedimentary differentiation from platform margin to intra-platform in depression period made the sedimentary paleogeomorphology in these two periods show features of“three ridges and two depressions”.The reef-shoal bodies mainly developed in the SQ2-LHST period,with vertical development positions restricted by the periodic oscillation of the lake level,and developed on the top of each high-frequency sequence stratigraphic unit in SQ2-LHST in the platform.The strike-slip fault activity controlled the distribution of the reef-shoal bodies on the plane by changing the sedimentary paleogeomorphology.The positive flower-shaped strike-slip faults made the formation of local highlands at the margins of and inside the shallow water platforms and which became high-energy sedimentary zones,creating conditions for the development of reef-shoal bodies. 展开更多
关键词 Santos Basin Brazil lower Cretaceous Barra Velha Formation lacustrine microbial carbonate high-frequency sequence sedimentary filling characteristics reef-shoal body development model
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