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1.
目的:探讨门静脉高压症猪肺血管的生物力学特性及为临床晚期肝硬化患者实施肝肺联合移植提供理论依据。方法:采用健康2月龄湖北白种猪4头作为正常对照组,四氯化碳诱导的门静脉高压组湖北白种猪10头,分别取其肺动脉、肺叶动脉、肺段动脉及肺静脉,在软组织生物力学试验机上测定压力一直径关系数据,推导出其弹性模量和顺应性。结果:与正常对照组相比,门静脉高压组(PHT)猪肺动静脉血管的弹性模量随血管内压力的升高而增大;顺应性则随血管内压力的增大而下降。结论:与人类相似,PHT猪可伴有肺血管生物力学特性的改变,且生物力学特性变化的幅度可能与病情变化有关。肝肺联合移植时,移植材料间的生物力学特性也应引起关注。  相似文献   

2.
目的:建立猪门静脉高压症模型,探讨门静脉高压症时门静脉的生物力学特性。方法:采用2月龄湖北白种猪,用四氯化碳、苯巴比妥、乙醇,配合高脂、低蛋白、低胆碱饮食进行混合饲养。通过脾静脉插管测压,取门静脉在生物软组织力学试验机上测定其压力-直径关系,横断取材,冰冻切片,H E法染色,用计算机图像分析系统测量其几何形态学指标。结果:实验组门静脉压为(4.17±1.03)kPa,对照组为(1.51±0.79)kPa(P<0.01),实验组门静脉的Einc、Ep和EV均随压力的上升而增大,在相同压力下明显大于对照组的Einc、Ep和EV。在0~4 kPa压力范围内实验组门静脉的顺应性(C)显著低于对照组,而在4~8 kPa的高压时两者顺应性差异并不明显(P>0.05)。结论:门静脉高压症时,门静脉的生物力学特性均发生了明显变化。肝移植时,移植材料间的生物力学特性也应考虑。  相似文献   

3.
目的观察大鼠肝内型门脉高压症形成中门静脉零应力状态及轴向拉伸时张应力.伸长比关系的动态变化,探讨门静脉生物力学特性的变化在门脉高压症形成中的作用。方法以60%四氯化碳(CCl4)皮下注射法制备肝内型门脉高压症大鼠模型,采用生物力学技术测定CCl4注射第2、4、6、8、10周大鼠门静脉零应力状态张开角和轴向拉伸时张应力,伸长比关系,并同步监测大鼠门静脉压力(PVP)、门静脉流量(PVF)、平均动脉压(MAP)、门静脉阻力(PVR)和内脏血管阻力(SVR)等血液动力学指标的动态变化。结果随着CCl4注射时间的延长,实验组大鼠的血液动力学指标发生了显著的变化。与之相对应.大鼠门静脉张开角及轴向拉伸参数b亦逐渐增大,从注射第10周起与对照组相比具有统计学差异(P<0.05)。结论门脉高压症大鼠存在高动力循环状态(HCS)。HCS可引起门静脉血管生物力学特性的变化。  相似文献   

4.
人与猪肝门静脉生物力学特性的比较研究   总被引:1,自引:0,他引:1  
目的:比较研究人与猪肝门静脉生物力学特性的异同,为猪→人异种肝移植提供理论依据。方法:取人与不同月龄猪肝门静脉,利用软组织生物力学试验机测量压力一直径关系数据,推导出其弹性模量和顺应性。结果:猪肝门静脉的弹性模量随月龄的增大和血管内压力的升高而增大;顺应性则随月龄的增大而下降。与人肝门静脉相比,6月龄猪肝门静脉的弹性模量和顺应性与人相近。结论:6月龄猪肝门静脉的力学特性与成人相近,在行猪→人异种肝移植时,人与6月龄猪肝门静脉的吻合是可行的。  相似文献   

5.
用CCl4注射法制备大鼠肝内型门脉高压模型,通过观察门静脉张开角的大小,研究肝内型门脉高压大鼠在模型建立过程中不同时间点门静脉零应力状态的变化。结果发现,在门脉高压症形成中.大鼠门静脉张开角逐渐增大,从CCl4注射第10周起与对照组相比有显著性差异(P〈0.05)。表明在门脉高压形成过程中,门静脉存在非均匀性生长,门脉高压大鼠门静脉的残余应力和应变大于正常大鼠。  相似文献   

6.
目的研究猪肝门静脉的生物力学特性与月龄间的关系,为猪→人异种肝移植提供力学资料。方法 取不同月龄猪肝门静脉,利用软组织力学试验机测量压力-直径关系数据,推导出其弹性模量和顺应性。结果 猪肝门静脉的弹性模量随猪的月龄的增大和血管内压力的升高而增大;顺应性则随猪的月龄的增大而下降。结论 猪肝门静脉的力学特性随增龄发生变化,在实施猪→人异种肝移植时应选择与人肝门静脉力学特性相匹配的月龄猪作为供体。  相似文献   

7.
目的探讨猪肝动脉弹性模量与性别的关系,为猪到人异种肝移植提供理论依据。方法取23例4、7月龄雌性、雄性、去势湖北白猪的肝动脉,将其按从近心端到远心端的方向分成近、中、远3段,各段置于4℃冰箱中待用。在软组织生物力学试验机上测定中段动脉的压力-直径关系,计算出增量弹性模量(Einc)、压力-应变弹性模量(Ep)和容积弹性模量(Ev)。结果 7月龄各组肝动脉的弹性模量有显著性差异(P0.01):雌性组最低,雄性组居中,去势组最高;7月龄各组与4月龄各组的弹性模量相比显著减小(P0.05)。结论 7月龄不同性别猪肝动脉弹性模量存在差异,从生物力学方面考虑,在猪到人异种肝移植时,应选择性别相匹配的猪肝脏作为供体材料,使移植材料肝动脉间的弹性模量尽可能相近,降低肝动脉并发症,有可能提高移植肝的存活率。  相似文献   

8.
目的:建立猪肝门静脉高压症模型,探讨肝门静脉高压症时肝门静脉的结构重建.方法:猪以四氯化碳、苯巴比妥、乙醇配合高脂、低蛋白、低胆碱饮食进行混合饲养.通过脾静脉插管测压,取门静脉常规石蜡包埋、切片,用H-E 染色法、Weigert法、Aniline blue法、Organge G法分别染组织结构、弹性纤维、胶原纤维和平滑肌,用计算机图像分析系统定量分析肝门静脉的几何形态及显微成分.结果:实验组肝门静脉压为(4.17±1.03)kPa,而正常组为(1.51±0.79)kPa,实验组门静脉的内膜与中膜增厚,管壁增厚,管径增粗,平滑肌、胶原纤维的百分含量增加,平滑肌细胞核的数密度和面密度也在增加,C/E值增加.结论:肝门静脉高压症时,与血液动力学改变相适应,肝门静脉的几何形态与显微结构成分均发生了改变.  相似文献   

9.
目的全面评价风心病二尖瓣病变肺高压的肺血管力学特性的变化规律。方法:借助右心导管技术和利用压力波形面积确定动脉顺应性的改进方法,通过测定肺血流动力学和肺血管顺应性。结果:①二尖瓣狭窄为主合并肺高压组的肺动脉血管零压顺应性Co较正常对照组明显下降(74.86±16.74ml/kPavs17.98±5.09ml/kPa,P(0.01),风心病合并严重肺动脉高压(PAPm>4.67kPa)比轻度肺动脉高压(PAP<4.67kPa)下降更为明显(20.86±6625ml/kPavs15.30±4.16ml/kPa,P<0.05);②MS组术前PAPm与反映血管型固有结构的Co之间呈显…  相似文献   

10.
目的应用超声造影检测门静脉高压患者肝内血流灌注相关参数,探讨其与门静脉压力的相关性及在门静脉高压中的应用价值。方法选择经临床诊断为门静脉高压并需要手术治疗的33例患者,其中男性24例,女性9例;年龄25~62岁,平均年龄49.67岁;Child-Pugh分级A级14例,B级17例,C级2例。于术前行超声造影检查。记录造影剂肝动脉到达时间(HAAT)、肝静脉到达时间(HVAT)、门静脉到达时间(PVAT),计算肝动静脉渡越时间(HA-VTT)、门静脉-肝静脉渡越时间(PV-HVTT)等造影参数,绘制时间-强度曲线;并在术中未行分流或阻断术前通过胃网膜右静脉测量门静脉压力,探讨上述造影参数与门静脉压力、Child-Pugh分级及食管静脉曲张程度的相关性。结果门静脉高压患者门静脉压力越高,HA-VTT、PV-HVTT呈逐渐降低趋势(r=-0.724、-0.764,P=0.000、0.000);食管静脉曲张重度组PV-HVTT[(-1.22±2.61)s]较轻-中度组PV-HVTT[(2.83±3.91)s]明显缩短,差异有统计学意义(P0.05);食管静脉曲张重度组门静脉压力[(3.59±0.81)k Pa]明显高于轻-中度组门静脉压力[(2.91±0.66)k Pa],差异有统计学意义(P0.05);Child-Pugh B级组HA-VTT[(4.02±2.35)s]较A级组HA-VTT[(7.47±1.22)s]明显缩短,差异有统计学意义(P0.05)。结论超声造影参数特别是HA-VTT、PV-HVTT与门静脉压力有良好的相关性,超声造影能够较好地评估门静脉高压。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   


15.
《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   

16.
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   

17.
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   

18.
19.
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   

20.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

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