电参数对钛微弧氧化膜层理化性能及细胞相容性的影响

目的:研究纯钛微弧氧化电参数（脉冲宽度及脉冲频率）的改变对膜层表面形貌、理化性能及成骨细胞生物行为的影响。 方法:对喷砂酸蚀钛片进行微弧氧化处理,通过脉宽及频率的变化,研究其对膜层的表面形貌、摩擦性能、耐腐蚀性等影响,分析得出不同表面形貌所对应的参数条件（脉冲频率400 Hz、脉冲宽度60 μs微弧氧化组为A组,脉冲频率500 Hz、脉冲宽度60 μs微弧氧化组为B组,脉冲频率500 Hz、脉冲宽度75 μs的微弧氧化组为C组）,进一步比较在该参数下的微弧氧化膜的耐腐蚀性及成骨细胞在其表面的粘附、增殖情况及细胞形态。 结果:电镜下3组试件表面均形成粗糙多孔的膜层,且A组纯钛微弧氧化膜表面粗糙度最高;C组所制备的微弧氧化膜层耐腐蚀性能及耐磨性优于A、B两组。细胞粘附及增殖实验A、B、C各组之间差异有统计学意义（P<0.05）,实验表明A组表面成骨细胞粘附及增殖均优于B、C两组。 结论:脉冲宽度及频率变化对微弧氧化膜层表面生物活性及理化性能均有影响,当脉冲频率400 Hz、脉冲宽度60 μs时,膜层表面的细胞生长最佳。     

He-Ne激光对大鼠离体颈上神经节快兴奋性突触后电位的影响

本文应用细胞内生物电记录技术，观测不同功率、不同照射时间的He-Ne激光（脉冲频率为1Hz、波长为632．8nm）对大鼠离体颈上神经节后神经元的膜电导和快兴奋性突触后电位（f-EPSP)的影响，以研究He-Ne激光对突触传递过程的作用机制。实验结果：（1）节后神经元快兴奋性突触传递过程对照射的He-Ne激光功率密度和照射时间的长短有选择性；（2）功率密度为2mW/cm^2的He-Ne激光对膜电导和f-EPSP的影响呈两个阶段：在照射初期（头2分钟内）引起膜电导增大（P＜0．05），同时f-EPSP由值增大（P＜0．05），甚至能产生动作电位；在激光照射后期（后3至10分钟）引起膜电导减少，f-EPSP幅值下降至低于照射前，并持续稳定较长一段时间；（3）功率密度为5mW/cm^2的He-Ne激光照射期f-EPSP幅值持续下降，不出现两阶段；（4）功率密度为2mW/cm^2的He-Ne激光的照射可降低快兴奋性突触后电位产生阈值，增加其发放频率。实验结论：（1）功率密度为2mW/cm^2，脉冲频率1Hz的He-Ne激光短时间照射可提高突触后膜上Na^ 、K^ 离子通透性，使膜电导增大而导致神经细胞突触过程的快兴奋性突触后电位幅值增加；（2）在功率密度为2mW/cm^2的He-Ne激光调节交感神经节快兴奋传递的过程中存在两时相效应，即激光照射初期的短时间增强效应和激光照射后期的长时间减弱效应。这表明了低功率激光对神经细胞作用的复杂性和时相性。这种特性与He-Ne激光照射引起呼吸链氧化还原状态变化而导致细胞生理状态变化的光生物机理有关；（3）低功率He-Ne激光照射对神经系统的整合作用有明显的作用。     

血管内皮细胞和脂肪干细胞体外联合培养细胞的增殖

背景:血管内皮细胞可有力支持脂肪干细胞向成骨方向转变,还可以加快血管的发生,为干细胞成骨提供营养支持。目的:探讨血管内皮细胞和脂肪干细胞体外联合培养对混合细胞增殖的影响。方法:设立单纯血管内皮细胞培养组、脂肪干细胞与血管内皮细胞按3∶1,1∶3,1∶1混合培养组、单纯脂肪干细胞培养组,加入含胎牛血清的L-DMEM,置于37℃、体积分数为5%的CO2饱和湿度培养箱中。倒置显微镜下观察细胞形态变化,改良MTT法绘制细胞生长曲线。结果与结论:脂肪干细胞与血管内皮细胞按3∶1,1∶1混合培养14d,细胞之间出现许多突触连接,部分细胞融合成团块状,其余培养方式均未见细胞团出现。随培养时间的延长,各培养方式下细胞吸光度值均逐渐升高,单纯脂肪干细胞培养、脂肪干细胞与血管内皮细胞按3∶1,1∶3,1∶1混合培养12d时细胞吸光度值达高峰,且按1∶1混合培养的吸光度值最高;而单纯血管内皮细胞培养10d吸光度值达高峰;随后各培养方式下细胞吸光度值逐渐下降。提示血管内皮细胞与脂肪干细胞体外联合培养,细胞能够相互促进增殖,1∶1混合比例条件下细胞增殖能力最强。     

脉冲电刺激对内皮细胞形态和功能的影响

探求脉冲电刺激对内皮细胞的形态、增殖以及蛋白表达的影响.选择在25 mV,频率分别为1、5、10、20、50和100 Hz的电刺激6 h作用于内皮细胞.MTT检测,分析细胞增殖.检测NO和ET-1值,分析内皮细胞蛋白表达.结果发现在10～100 Hz脉冲电刺激作用下,内皮细胞增殖明显.NO的表达在20～100 Hz电刺激作用下明显高于对照组.在1 Hz脉冲电刺激作用下ET-1的分泌量低于对照组,而20～100 Hz时则明显高于对照组.可以看出,脉冲电刺激对内皮细胞的增殖和NO、ET-1表达都产生了影响.尤其是50 Hz脉冲电刺激对于加强内皮细胞功能、维持血管生物学特性有着积极的作用.     

骨髓间充质干细胞与髓核细胞的体外共培养

背景：细胞移植治疗椎间盘退行性变目前尚处在实验室研究阶段。 目的：通过SD大鼠骨髓间充质干细胞与退行性改变的髓核细胞体外共培养,探索骨髓间充质干细胞能否通过直接接触促进髓核细胞外基质的表达以及髓核细胞能否诱导骨髓间充质干细胞向类髓核细胞分化。 方法：取已自然退变的第6代髓核细胞与生长良好的第4代骨髓间充质干细胞按不同比例(75∶25,50∶50和25∶75)体外共培养7 d,单独髓核细胞(100∶0)与单独骨髓间充质干细胞(0∶100)分别作为阳性对照和阴性对照。 结果与结论：RT-PCR检测显示共培养组(75∶25和50∶50)蛋白多糖和Ⅱ型胶原蛋白条带均明显亮于单独髓核细胞培养组(100∶0),吸光度值比较差异有显著性意义;免疫组织化学检测显示Ⅱ型胶原蛋白在共培养组(75∶25和50∶50)胞浆内的表达明显高于单独髓核细胞培养组(100∶0)。共培养组中可见骨髓间充质干细胞由长梭形向多角形、类圆形转变,胞浆内异染颗粒增多。提示通过体外直接接触共培养,骨髓间充质干细胞能逆转髓核细胞退变,而且髓核细胞能诱导骨髓间充质干细胞向类髓核细胞转换。     

用于辐照成骨细胞的低频多波形磁场发生仪的研制

本文介绍了用于辐照成骨细胞的低频多波形磁场发生仪。仪器主要由信号产生、功率放大和电磁转换三部分组成，所产生的磁场频率0Hz～150Hz、强度0mT-50mT，波形分别为脉冲、矩形、三角和正弦四种。使用表明，仪器参数设置方便、工作稳定和辐照区磁场均匀性好。     

不同电刺激信号对大鼠雪旺细胞增殖的影响

目的研究不同的电刺激信号对大鼠雪旺细胞(RSC96)增殖的影响。方法实验使用RSC96细胞系(中国科学院典型培养物保藏委员会细胞库),经过2次传代培养,以1.25×10~4/孔的密度种植于24孔细胞培养板中,次日电刺激信号分别采用不同的电压(10、100、500、1 000、5 000、10 000 m V/cm)、不同的频率(0.1、1.0、100.0、1 000.0、10 000.0、1 000 000.0 Hz)、不同的脉冲占空比(5%、10%、30%、50%、70%、90%)及不同的波形(正脉冲波、矩形波、三角波、正弦波、杂波、直流波)对细胞进行电刺激,每组设置3个平行样,细胞每天刺激30 min,持续刺激4 d。采用四甲基偶氮唑盐(MTT)法检测细胞增殖率。结果当电刺激频率为100.0 Hz、脉冲占空比为50%、波形为矩形波时,电压500 m V/cm时对细胞的增殖具有抑制作用。当电刺激频率为100.0 Hz、脉冲占空比为50%、电压为500 m V/cm时,正脉冲波、正弦波、矩形波和三角波都能够促进细胞的增殖。当电刺激波形为矩形波、脉冲占空比为50%、电压为500 m V/cm时,频率100.0~1 000.0 Hz组细胞增殖率最高。当电刺激波形为矩形波、频率为100.0 Hz、电压为500 m V/cm时,不同的脉冲占空比对细胞增殖的影响不明显。结论不同的电刺激信号条件对细胞增殖的影响较大。电压≤500 m V/cm、有规律的脉冲波形、频率为100.0~1 000.0 Hz电刺激信号能够获得较好的RSC96增殖的效果。实验所获得的优化电刺激参数在外周神经修复中具有非常大的应用前景。     

不同刺激参数对SD大鼠肌肉收缩的影响

目的研究不同电刺激参数对SD大鼠肌肉收缩的影响,为临床应用电刺激治疗周围神经损伤提供参考。方法采用低频脉冲发射器对SD大鼠的颈项部肌群进行局部电刺激。刺激时改变频率、脉宽、电压及占空比等参数,观察参数变化对肌肉收缩及动物行为的影响。同时记录受刺激肌肉的肌电图。结果 8只SD大鼠在10~60Hz的频率范围内,随频率增加肌肉收缩率逐步增强。肌电图结果显示在刺激频率不变的前提下,随脉宽的增加（50~200μs）,肌电幅值显著上升,且肌电幅值的变化与大鼠行为改变成正相关。结论不同的刺激参数可影响肌肉的收缩状态与强度,选择合适的参数可使失神经支配肌肉发生有节律地收缩,防止肌萎缩,并有助于建立局部肌痉挛动物模型。     

不同个体及不同情绪状态下手臂阻抗的频率特性

目的：研究低频电流（f≤1000Hz）作用下,不同个体及同一个体在不同情绪状态下,其手臂阻抗值随电流频率变化的规律,为生物电阻抗技术的临床应用和基础医学的实验研究提供有益的借鉴。方法：在50Hz-1000Hz频率范围内,分别测量男女大学生在平静、快速阅读和快速心算三种不同情绪状态下的手臂阻抗值,并描记出其频率响应曲线。结果：（1）平静状态下,男生手臂阻抗平均值略大于女生的;交流电频率越大,人体手臂阻抗值越小;在0Hz〈f≤100Hz的低频段,手臂阻抗值受交流电频率的影响很大：在100Hz〈f≤1000Hz的频段,手臂阻抗值受交流电频率的影响变小,表明了手臂组织具有容性成分。（2）不同个体的手臂阻抗值有较大差异,但任意个体的频率特性都具有相同的变化规律。（3）在紧张情绪状态下,人体手臂阻抗值随交流电频率的变化规律与平静时的变化规律相同;但紧张情绪会引起手臂阻抗的减小,同一个体情绪越紧张,阻抗值越小。结论：人体手臂阻抗值存在较大的个体差异,同一个体的手臂阻抗值与交流电频率及情绪变化均有密切关系,对这一生理参数的测量有着重要的应用前景。     

锁定钢板外置与单臂一体式外固定支架固定骨折的生物力学研究

[摘要] 目的 通过对锁定钢板（LCP）外置与外固定支架固定骨折的生物力学的研究分析，为临床应用锁定钢板外置固定治疗提供理论依据。方法 选择不同长度的牛小腿骨（胫骨20条形成骨折标本并随机分成两组），分别采用锁定钢板外置固定和外固定支架固，观察标本在不同的载荷下承受的轴向压缩、扭转和弯曲作用下变化情况。结果 两组在100、200、300、400、500、600、700N载荷轴向压缩值比较差异均有统计学意义（P<0.05），且随着载荷越大则轴向压缩值差距越大。两组在4、6、8、10、12、14N.cm扭转角度比较差异均有统计学意义（P<0.05），且随着载荷越大则扭转角度值差距越大。两组在50、100、150、200、250、300 N载荷弯曲位移值比较差异均有统计学意义（P<0.05），且随着载荷越大则弯曲位移值差距越大。结论 锁定钢板外置固定骨折在轴向压缩、扭转和弯曲等生物力学方面优于外固定支架，其在临床治疗开放性骨折方面有着潜在的应用价值。     

Renal dysplasia and asplenia in two sibs

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.     

Schizophrenia in a North Swedish geographical isolate, 1900–1977. Epidemiology, genetics and biochemistry

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.     

The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome: Substrate beriberi

About 1900, modern food selection and processing caused widespread $\text{epidemics}$ of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a $\text{panh}$ypovitaminosis B, i.e., a mixture of $\text{substrate}$ beriberi and $\text{substrate}$ pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse $\text{endemic}$ disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for $\text{primates}$. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.     

What will studies of Fulani individuals naturally exposed to malaria teach us about protective immunity to malaria?

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.     

'Very sore nights and days': the child's experience of illness in early modern England, c.1580-1720

Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.     

Guidelines for the Validation and Use of Immunoassays for Determination of Introduced Proteins in Biotechnology Enhanced Crops and Derived Food Ingredients

Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.     

Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)

The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.     

HLA in North Colombia Chimila Amerindians

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.     

The universal muscular chamber. A basic unit of the genitourinary, cardiovascular, gastro-intestinal, skeletal, cutaneous, respiratory and other systems, endocameral hypertension; and spasm, the key to their idiopathic diseases and arthropathies

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.