共查询到20条相似文献,搜索用时 78 毫秒
1.
用过碘酸——氮基硫脲——蛋白银细胞化学方法观察绵羊口腔真角化上皮(硬腭、齿板和丝状乳头)和类角化上皮(软腭)中两型膜包鞭粒的糖蛋白性质。Ⅰ型颗粒(硬腭和软腭)的周边内含物富含糖蛋白,而中央内含物不具有糖蛋白的性质。硬腭和软腭上皮中,被覆于上皮细胞胞膜表面的电子致密物富含糖蛋白。这层物质来自Ⅰ型颗粒。这些糖蛋白物质可能是上皮渗透屏障的组成成分之一。Ⅱ型颗粒(齿板,丝状乳头和软腭)不与过碘酸——氨基硫脲——蛋白银方法反应。 相似文献
2.
本实验用3种不同固定液固定不同年龄的绵羊口腔上皮,用透射电镜观察上皮细胞中透明角质颗粒的超微结构。本文的结果表明:1.绵羊口腔上皮存在两种类型透明角质颗粒。Ⅰ型颗粒的形态结构随上皮发育而变化,它从圆形颗粒变成与张力细丝束结合后的不规则形颗粒,最后颗粒从成年动物口腔上皮的某些部位消失。Ⅱ型颗粒呈圆形或椭圆形,周边有游离核蛋白体围绕,其形态结构不随上皮发育而变化。自发生后这种颗粒始终存在于成年动物口腔上皮中。2.根据两型颗粒与不同固定液的反应,Ⅰ型颗粒的组成成分具有脂蛋白性质,而Ⅱ型颗粒除有脂蛋白性质外,还具有不饱和脂类的性质。 相似文献
3.
大鼠松果体囊上皮表面的扫描电镜观察 总被引:2,自引:0,他引:2
目的 探讨松果体激素释放到蛛网膜下隙脑脊液途径的结构基础.方法 对1.5月龄和12月龄大鼠松果体浅部,进行松果体囊表面的扫描电镜观察.结果 在大鼠松果体囊表面发现存在筛状囊上皮孔和喇叭口状囊上皮孔.筛状囊上皮孔主要存在于1.5月龄大鼠的松果体囊上皮,是由许多密集排列的囊上皮细胞周边部细胞膜凹陷形成的圆形孔洞,筛孔直径200~500 nm;喇叭口状囊上皮孔见于1.5月龄和12月龄大鼠的松果体囊表面,由相邻上皮细胞向松果体内部凹陷,形成圆形或椭圆形开口,孔径1~4 μm.在两组动物的松果体囊表面,可见到直径800~1 000 nm的球形分泌颗粒样结构.结论 松果体分泌颗粒的释放形式,可能存在连同颗粒被膜的整体释放;松果体激素或分泌颗粒,可能会通过松果体囊上皮孔,直接进入蛛网膜下隙的脑脊液. 相似文献
4.
胎儿肺泡上皮和气血屏障的电镜观察 总被引:6,自引:0,他引:6
为阐明不同胎龄肺泡表面上皮和气血屏障的发育状况,对24例受精龄为14~40周的人胎肺脏,进行透射电镜观察。胎龄19周时,即可辨认肺泡Ⅰ型上皮细胞和气血屏障。图像分析表明,气血屏障的厚度,随胎龄的增长而变薄。Ⅱ型肺泡上皮细胞,在胎龄20周后逐渐分化,22周时胞质内出现板层小体,小体的截面积随胎龄而增大。本文着重对气血屏障及Ⅱ型上皮细胞的形态变化进行了讨论。 相似文献
5.
不同性别和发育阶段的小鼠下颌下腺颗粒曲管的上皮生长因子免疫组… 总被引:1,自引:0,他引:1
对不同性别和不同年龄组的小鼠下颌下腺颗粒曲管产生上皮生长因子的功能进行了免疫组化的体视学研究。结果显示:2周龄小鼠颗粒曲管呈上皮生长因子免疫反应阴性,2月龄呈阳性反应。随年龄增长,颗粒曲管数量增多,反应增强。同龄相比,雄性反应雌性强,雄性颗粒曲管发育较雌性好。 相似文献
6.
在切除大鼠刚髭部皮肤的刺激下,从常规醛-锇酸固定的三叉神经脊束核尾侧亚核的超薄切片中观察到:1.大颗粒小泡轴突终末非突触部位的胞吐影像;2.含致密物质的大有衣小泡,由终末质膜内陷而成,提示大颗粒小泡在终末通过有衣小泡进行膜再循环;3.大颗粒小泡也可由含致密物质的平滑内质网样的管状结构形成。本研究支持大颗粒小泡在非突触部位,通过胞吐释放递质或神经调节物的假说。 相似文献
7.
本实验用电镜观察了4~19周人胎盘。结果发现:妊娠4~5周时,绒毛膜绒毛的合体滋养层中,含有丰富的来源于高尔基复合体的颗粒。颗粒由一单层界膜所包绕,其直径0.5~1.5μm,并以较低的电子密度与脂滴相区别.在浓缩过程中,许 相似文献
8.
神经垂体多肽激素分泌颗粒释放形式和转运途径的形态学研究 总被引:7,自引:1,他引:6
目的探讨神经垂体多肽激素分泌颗粒的释放形式和在细胞外正常转运途径的结构基础。方法对大鼠神经垂体进行光镜、透射电镜和扫描电镜观察。结果神经垂体主要由无髓神经纤维、垂体细胞及富含毛细血管的结缔组织组成。毛细血管内皮为有孔型(50nm),外有基膜与血管周隙分隔。完整的大型膜包分泌颗粒(100~300nm)不仅大量存在于无髓神经纤维内,而且也见于血管周隙内。垂体囊由单层扁平上皮细胞和上皮下结缔组织构成,囊上皮细胞间存在许多不规则的囊上皮孔(2~5μm),上皮孔附近经常可见分泌颗粒。结论这些结构特征提示,神经垂体多肽激素或分泌颗粒的释放形式,存在一种连同颗粒被膜的整体释放;释放入血管周隙内的多肽激素或分泌颗粒,更易经组织间隙、囊上皮孔进入脑脊液发挥旁分泌作用,而非直接通过毛细血管壁进入血液。 相似文献
9.
对不同性别和不同年龄组的小鼠下颌下腺颗粒曲管产生上皮生长因子的功能进行了免疫组化和体视学研究.结果显示:2周龄小鼠颗粒曲管呈上皮生长因子免疫反应阴性,2月龄呈阳性反应.随年龄增长,颗粒曲管数量增多,反应增强.同龄相比,雄性反应较雌性强,雄性颗粒曲管发育较雌性好.体视学结果显示:颗粒曲管的截面积、周长、等效直径及其上皮生长因子的相对含量均与年龄呈明显的正相关.同龄相比,雄性小鼠上述参数明显大于雌性.实验结果为评估下颌下腺的发育状况和生理功能,为确立从下颌下腺提取上皮生长因子的最佳时间提供了重要的实验依据. 相似文献
10.
良性上皮样外周神经鞘膜肿瘤(BEPNST)是一种罕见的软组织肿瘤,其临床病理学特点以及与普通型雪旺瘤和神经纤维瘤的关系还不清楚。以前文献中该肿瘤大多数被作为良性上皮样雪旺瘤而报道。为了阐明BEPNST的临床病理学特征,作者报道了33例BEPNST,其中女性22例,男性11例,年龄2—68岁,平均31.5岁。仅有1例患者可能有Ⅰ型神经纤维瘤病。肿瘤主要位于真皮和皮下,下肢15例, 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
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
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 Gc
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.
Donald O. Rudin 《Medical hypotheses》1982,8(1):17-47
About 1900, modern food selection and processing caused widespread 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 ypovitaminosis B, i.e., a mixture of beriberi and pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse 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 . 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. 相似文献
14.
Marita Troye-Blomberg Charles Arama Jaclyn Quin Ioana Bujila Ann-Kristin Östlund Farrants 《Scandinavian journal of immunology》2020,92(4):e12932
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
15.
16.
Newton H 《Medical history》2011,55(2):153-182
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. 相似文献
17.
C. R. Lipton J. X. Dautlick G. D. Grothaus P. L. Hunst K. M. Magin C. A. Mihaliak F. M. Rubio J. W. Stave 《Food and Agricultural Immunology》2000,12(2):153-164
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. 相似文献
18.
Antonio Arnaiz-Villena Jose Palacio-Grüber Ignacio Juarez Ennio Hernández Ester Muñiz Brayan Bayona Cristina Campos Jorge Nieto Manuel Martin-Villa Carlos Silvera 《Human immunology》2018,79(4):189-190
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
19.
Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)
Konrad Joachim Böhm 《Acta histochemica》1980,66(1):59-84
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. 相似文献
20.
M G Baggot 《Medical hypotheses》1979,5(5):591-597
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