首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
针对现有人工肛门括约肌系统无供能装置或供能装置更换可能引发感染等问题,本文提出了电磁谐振耦合的无线供能方法,对人工肛门括约肌系统进行非接触的经皮无线供能.本文在对能量传输电路、发送接收线圈参数研究基础上,提出通过选择SRC电路作为发射、接收端耦合电路以增大铁芯耦合面积,从而提高发射及接收线圈Q值,进而提高能量传输效率.实验结果表明,使用G25磁芯线圈进行电磁耦合,当两线圈轴向距离为10mm时,能量传输效率可高于60%,可保证人工肛门括约肌系统的正常工作.  相似文献   

2.
目的胶囊内镜机器人受尺寸限制和安全性等因素的影响,传统锂电池或拖缆式供能已不能满足要求,如何提供有效的供能方式成为其发展的重大瓶颈。随着无线供能方式的提出,基于电磁感应的无线能量传输被视为一种有效解决该问题的供能方式。方法设计了一个在任意姿态下接收线圈均能高效稳定供能胶囊机器人的无线能量传输系统。首先设计了符合赫姆霍兹线圈结构的双螺线管对线圈作为发射线圈,再结合机器人结构特征设计新型的磁芯结构和绕线方式,构成新型三维正交接收线圈。最后在由发射线圈和体外控制电路组成的可调谐发射平台上进行了0~360°范围内系统有效接收效率的测试。结果该系统能量传输效率在线圈任意姿态不低于4.95%,解决了因接收线圈姿态变化导致的供能不足问题。结论在输入功率为10.88 W条件下能提供最少544 m W的能量,实验验证了该系统的可行性。  相似文献   

3.
体外能量发射装置是胶囊内窥镜无线供能系统中很重要的一部分。为了使胶囊内窥镜获得较稳定能量,同时研究传输效率和人体安全性与谐振频率的关系,设计了一种可在人体消化道区域内产生均匀交变电磁场、谐振频率在10—400kHz范围内调节的体外能量发射装置。根据无线供能系统的要求设计了该装置的发射线圈、驱动电路,并实际搭建了整个装置。实际使用验证了该能量发射装置设计的可行性,并取得了较好的效果。  相似文献   

4.
目的提出一种适用于植入式医疗设备的无线供电系统,引入磁谐振耦合供能的方法,并通过建立理论线圈仿真模型计算线圈尺寸与谐振频率,有效解决植入式装置无线供电距离远、尺寸小等难题,使植入式装置可无需更换电池而终生使用。方法首先通过MATLAB仿真耦合谐振线圈模型以及无线能量传输模型,并计算出满足条件的最优线圈设计。然后依据仿真结果制作发射线圈与接收线圈,设计植入式无线供电实际硬件系统,使系统在限定的距离等条件下有最优的传输效率。结果仿真算法能有效描述磁耦合谐振,计算与测量可以得到Q、L的理论与实际的平均相对误差E_Q=5.34%、E_L=4.42%,为实际供电系统的设计提供了参考依据。设计实现了适合于医疗植入的微型供电系统,增加了传输距离。该方案采用线圈大对小设计,植入部分尺寸仅有18 mm,体外线圈直径85mm,实际最高传输效率达到16.20%,80 mm距离可以供能2.642 m W。结论该仿真算法可为耦合谐振设计提供参考,为植入式医疗系统提供一种新的设计方案。  相似文献   

5.
目的 设计、研制一种用于实验动物的全植入式血糖浓度检测系统,通过一次植入手术可获得实验动物自然状态下经无线方式传输的动态血糖监测数据.方法 监测系统包括植入体和体外接收端两部分.植入体尺寸设计为11.5 mm×16.0 mm×5.0 mm,不超过实验大鼠体积的1/10.以SOF-SENSOR植入式葡萄糖传感器及其外围三电极伏安测量电路为核心,采用锂电池和稳压芯片构建供电,测量数据通过CC2540低功耗蓝牙系统芯片无线传输至体外.植入体外层包裹医用硅胶材料,以保护电路和提高植入体生物相容性.结果 体外验证实验表明,本系统可在2~34 mmol/L范围较准确地测量葡萄糖浓度(r=0.996 7),平均标准误差为0.193 mmol/L,灵敏度为9.24 nM(mmol/L),能够满足设计要求.结论 植入式实验动物血糖动态监测装置体积小,适合植入.体外血糖测量验证实验表明本装置的血糖测量范围、准确性、灵敏度及标准误差等均能满足设计要求.此装置有望为糖尿病病理和药效学研究提供重要的技术支持.  相似文献   

6.
目的 为全方位监测心电信号并弥补单一导联心电检测的不足,设计并实现了一种基于无线能量传输技术的植入式三路心电遥测系统.方法 系统由无线能量传输设备供能,植入式微型电子胶囊检测心电信号,数据记录仪无线接收数据并由数据处理软件处理.直流供电下分别采用模拟心电信号、正弦信号、方波信号通过模拟实验验证了系统的性能.无线供能下信号线屏蔽后并埋在猪肉中进行体外实验.结果 模拟实验胶囊能够采集三种信号,体外实验测得有噪声的信号波形.结论 直流供电下胶囊正常工作,无线供能下猪肉对磁场有一定程度的屏蔽作用.  相似文献   

7.
目的 为全方位监测心电信号并弥补单一导联心电检测的不足,设计并实现了一种基于无线能量传输技术的植入式三路心电遥测系统.方法 系统由无线能量传输设备供能,植入式微型电子胶囊检测心电信号,数据记录仪无线接收数据并由数据处理软件处理.直流供电下分别采用模拟心电信号、正弦信号、方波信号通过模拟实验验证了系统的性能.无线供能下信号线屏蔽后并埋在猪肉中进行体外实验.结果 模拟实验胶囊能够采集三种信号,体外实验测得有噪声的信号波形.结论 直流供电下胶囊正常工作,无线供能下猪肉对磁场有一定程度的屏蔽作用.  相似文献   

8.
电磁耦合谐振式无线电能传输技术利用两个具有相同谐振频率、高品质因数的线圈,当其处于谐振状态时,通过电磁振荡、依靠非辐射场来实现能量的高效传输,因具有较好的距离、空间自由度和效率优势,成为人体植入式装置无线能量供给的创新方法。针对心脏起搏器能量无线传输问题,设计一种新型的植入式天线系统。为验证其人体辐射安全性,针对人体胸腔构建3层介质模型,应用时域有限差分(FDTD)方法,使用HFSS软件对胸腔比吸收率(SAR)进行数值仿真。结果表明,在线圈间距10 mm,中间具有0.1 mm空气层、0.2 mm皮肤层和约9.7 mm肌肉层,激励为9.17 MHz、1 W的条件下,利用这个天线系统对人体植入式设备进行无线能量传输,正常工作情况下10 g生物组织的平均SAR值为0.009W/kg,非正常工作情况下10 g生物组织的平均SAR值最大为0.823 W/kg,均低于国际非电离辐射防护委员会(ICNIRP)制定的安全标准,从而验证该植入式天线系统对人体影响的安全性。  相似文献   

9.
采用电磁感应方式为体内胶囊内窥镜供能时,人体必然暴露于发射线圈产生的强电磁场中.本研究采用数值计算的方法,在包含62种人体组织、分辨率为0.33 mm×0.33 mm×2 mm的三维真实人体仿真模型上求解人体不同组织在该电磁场中的感应电流密度和比吸收率,并根据国际非电离辐射防护委员会安全性标准对其进行安全性评估.结果表明,发射功率为25 W,谐振频率为266.5 kHz的能量传输系统产生的电磁场对人体是安全的.本研究为无线能量传输系统奠定了生物安全性基础.  相似文献   

10.
一种用于体内诊疗装置的无线能量传输方案   总被引:4,自引:0,他引:4  
针对体内的诊疗装置的能量供给问题,笔者提出了一种无线能量传输的方案;同时还设计了一套可进行无线能量传输的装置.实验结果表明,用该装置能够有效地进行能量的无线传输.  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

14.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

15.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

16.
Introduction: The etiology of atopic dermatitis (AD) is multifactorial with interaction between genetics, immune and environmental factors.

Areas covered: We review the role of prenatal exposures, irritants and pruritogens, pathogens, climate factors, including temperature, humidity, ultraviolet radiation, outdoor and indoor air pollutants, tobacco smoke exposure, water hardness, urban vs. rural living, diet, breastfeeding, probiotics and prebiotics on AD.

Expert commentary: The increased global prevalence of AD cannot be attributed to genetics alone, suggesting that evolving environmental exposures may trigger and/or flare disease in predisposed individuals. There is a complex interplay between different environmental factors, including individual use of personal care products and exposure to climate, pollution, food and other exogenous factors. Understanding these complex risk factors is crucial to developing targeted interventions to prevent the disease in millions. Moreover, patients require counseling on optimal regimens for minimization of exposure to irritants and pruritogens and other harmful exposures.  相似文献   


17.
《Human immunology》2022,83(11):739-740
Georgia (or Sakartvelo in its own language) is a South Caucasus Mts. country with its easternmost part is enigmatically named Iberia, like the Iberian Peninsula, which may refer to rivers “Kura” and “Ebro” or their valleys respectively. Most of their inhabitants speak Georgian which is included within Dene-Caucasian group and Usko-Mediterranean subgroup of languages. The latter includes Basque, Berber, ancient Iberian-Tartessian, Etruscan, Hittite, Minoan Lineal A and others. In the present paper, HLA class II -DRB1 and -DQB1 alleles has been studied and extended haplotypes calculated. Most frequent haplotypes are also of Mediterranean origin (i. e.: (A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*51)-DRB1*13:01-DQB1*06:03, or (A*24-B*35)-DRB1*01:01-DQB1*05:01) and DA genetic distances show that closest world populations to Georgians are Mediterraneans. Georgians also show common extended haplotypes ((A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*13)-DRB1*07:01-DQB1*02:01 and (A*03-B*35)-DRB1*11:01-DQB1*03:01) with Svan people, a secluded population in North Georgia mountains. We can conclude that Georgians belong to a very old Mediterranean substratum according to both linguistics (Usko Mediterranean languages) and HLA genetics.  相似文献   

18.
《Human immunology》2020,81(5):193-194
Huastecos or Teenek Amerindians are presently living at North East Mexico (San Luis Potosi State). They have probably one of the most ancient culture of Mexico and Central America together with Mayas and Olmec groups with which also show close relationships. Proximity to Atlantic Ocean/Mexican Gulf originated that Spaniards had very early contact with them at about 1519 CE or before. In the present paper we have aimed to study HLA gene profile which may be useful for HLA and disease epidemiology and transplant programs in Teeneks. HLA-DRB1*04:07, -DRB1*14:06 and -DRB1*04:11 have been found in high frequency like in other Amerindian groups. High frequency typical Amerindians HLA extended haplotypes have been found, such as A*02-B*35-DRB1*04:07-DQB1*03:02; A*68-B*39-DRB1*04:07-DQB1*03:02 and A*02-B*39-DRB1*04:07-DQB1*03:02; also new haplotypes have been described, like A*02-B*52-DRB1*04:11-DQB1*03:02, A*68-B*35-DRB1*14:02-DQB1*03:01 and A*68-B*40-DRB1*16:02-DQB1*03:01. Genetic proximity is observed not only to linguistically close Mayans, but also to Mazatecans, Mixtecans and Zapotecans, who speak an altogether different languages; it shows once more that genes and languages do not correlate. This population was greatly diminished after European contact between 1500 and 1600 years CE; in fact, North and South America First Inhabitants population was brought from 80 down to 8 million people because of diseases (i.e.: measles, smallpox or influenza), slavery and war.  相似文献   

19.
Direct oral anticoagulants (DOAC) are indicated for stroke prevention in atrial fibrillation and for the prevention and treatment of venous thromboembolism. As any anticoagulant, they are associated with a bleeding risk. Management of DOAC-induced bleeding is challenging. Idarucizumab, antidote for dabigatran, is currently available and is part of the therapeutic strategy, whereas antidotes for anti-Xa agents are under development. Activated or non-activated prothrombin concentrates are proposed, although their efficacy to reverse DOAC is uncertain. We propose an update on DOAC-associated bleeding management, integrating the availability of idarucizumab and the critical place of DOAC concentration measurements.  相似文献   

20.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号