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1.
Four specific antigens (trophoblastic beta 1-globulin, placental lactogen, alpha 1- and alpha 2-globulins of human placenta) were identified using antisera to the native amniotic fluid. Five antigens with the mobility of prealbumins, alpha 1-globulins, alpha 2-globulins and beta 2-globulins which bear no resemblance with the previously studied antigens were identified using antisera to the acid fraction of the amniotic fluid. Both the prealbumins and alpha 2-globulin were found in the blood serum of foetuses of different age and of newborn infants; these proteins were absent from the blood serum of pregnant women and donors. They received the names of embryonic prealbumine 1, embryonic prealbumine 2 and embryonic alpha 2-globulin. The protein with the mobility of alpha 1-globulins was found in the amniotic fluid of foetuses and in the blood serum of pregnant women only and received the name of amniotic alpha 1-globulin. The concentration of the antigens in question was studied in the developing foetuses and in the blood serum of pregnant women at different stages of pregnancy.  相似文献   

2.
The hypothalamic-hypophysial neurosecretory system (HHNS) was studied in the human foetuses from the age of 8 weeks till birth. The hypothalamus of 8 weeks old foetuses is weakly differentiated, no individual cell groups, so-called nuclei, are identified. The supraoptic (SON) and paraventricular (PVN) nuclei are identified from the age of 12 weeks on. The size of cell nuclei increases with the age. The Homori-positive granules were first found in some SON and PVN cell and in neurohypophysis in the 18 weeks old foetuses. It was shown under the electron microscope that the neurohypophysis of 8 weeks old foetuses consisted mainly of pituicytes with axons among the cytoplasmic processes of the latter. After the age of 10 weeks, the area of parenchyma of the neurohypophysis occupied by axons increased and typical elementary neurosecretory granules appeared in them. The data obtained are discussed with respect to the participation of HHNS in the regulation of water metabolism in the human foetuses.  相似文献   

3.
Tn, sialosyl-Tn and T antigens are simple mucin-type carbohydrate antigens that may be expressed in human neoplasies due to alteration of the glycoprotein biosynthetic pathway. Utilising specific monoclonal antibodies (HB-Tn1, HB-STn1 and HB-T1), we have investigated the expression of these simple mucin-type carbohydrate antigens in large intestine of 8 human foetuses at early gestational age (9-10 weeks), obtained after therapeutic abortion. In all cases the expression of Tn antigen was mainly localised as a thin rim at the cell membrane and occasionally in the supranuclear region of epithelial cells, while sialosyl-Tn antigen was documented in some goblet cell vacuoles and occasionally in the cytoplasm of columnar cells. T antigen was not expressed in any case. These results indicate that Tn and sialosyl-Tn antigens are expressed as early as nine weeks of gestation, further supporting the notion that they may be considered as oncodevelopmental cancer-associated antigens in the large intestine.  相似文献   

4.
Differentiation of the palatine tonsillar tissues of the human fetus]   总被引:1,自引:0,他引:1  
Differentiation of epithelial and lymphoid tissues of the palatine tonsils was studied in human embryos at the age of 8-34 weeks of development by means of histochemical, immunomorphological and morphometric methods. The anlage of the palatine tonsils appears at the age of 9 weeks of fetal development. At the age of 13-14 weeks of fetal development the tonsil suspension contains 2 subpopulations of lymphocytes possessing properties of T-cells differing in the ability of their superficial receptors to interact with sheep erythrocyte antigens forming rosettes (RFC--rosette forming cells) and with antigens of their own erithrocytes (autoRFC). The number both increases sharply by the 16th week of gestation. Simultaneously, essential alterations are noted in epithelial and lymphoid tissues. In epithelium of crypts cornified cells appear; the amount of lymphoid tissue increases sharply, primary follicles without reactive centers appear, lymphocytic infiltration of epithelium occurs. The amount of RFC does not change considerably, and the amount of autoRFC has a tendency towards some increase. From the data obtained, it is possible to suggest that human palatine tonsils already at embryonic period participate in functioning of immunogenic organs and in maintaining of immunologic homeostasis of the fetal organism.  相似文献   

5.
The activity and distribution of y-GT was investigated in a number of organs from human foetuses aged from 14 to 24 weeks post menstruationem. Over this period, enzyme activity increased in the kidney, pancreas and thymus, but decreased in the small intestine. No trend could be established for the liver, although activity was high. In the lung, spleen, brain and adrenals, y-GT was either detectable at very low levels or could not be demonstrated. The possible relationship between y-GT activity in some human tumours and the enzyme level in the corresponding foetal organs is discussed.  相似文献   

6.
A 4-fold increase in protein disulfide isomerase (PDI) mRNA is observed in brain of 10 days-old rats and in liver of 20 days-old foetuses when compared with 20 days-old (brain) and 18 days-old (liver) foetuses respectively. During further postnatal development, the mRNA for PDI decreases in both organs to the initial values present in foetuses and remains practically unchanged in brain till the adult. By contrast in liver by 35-40 days after birth, and coincident with sexual maturation, there is a 2.5-fold increase in PDI mRNA that is maintained by 55 days (adult). These results clearly show that protein disulfide isomerase gene expression is differentially regulated in liver and brain during rat development.  相似文献   

7.
Ultrasonography was used in six saddle back tamarin females (Saguinus fuscicollis) to diagnose pregnancy, monitor the patterns of uterine growth and embryonic/foetal development and examine the incidence loss of single embryos/foetuses. Pregnancy was reliably diagnosed 17 days after conception, 10 days earlier than by plasma progesterone measurement. The patterns of uterine and embryonic/foetal growth paralleled those reported for the common marmoset, including a delay in embryonic development. The results support the hypothesis of retardation of organogenesis in most callitrichid species. Individual embryos could be reliably identified from day 50 of pregnancy; a loss of single embryos/foetuses after this stage did not occur. All pregnancies were carried to term, resulting in five times twins and one singleton. The smaller litter size compared to the common marmoset may be due to loss of single embryos at earlier stages of pregnancy or to a lower ovulation rate.  相似文献   

8.
Summary A library of hybridoma cell lines has been established which produce monoclonal antibodies against antigens from the germinal vesicle ofXenopus laevis oocytes. Many of the antigens are also found in the nuclei ofXenopus embryonic cells in culture. The fate of two of these antigens during embryogenesis was traced by immunofluorescence on embryo and tadpole sections. Early in development these antigens appear to be evenly distributed in the nuclei of all cells. In later stages they gradually disappear from most embryonic structures but are strongly accumulated in the nuclei of some specific cell types and organs.  相似文献   

9.
Immunoblotting showed that a monoclonal antibody, 3A10, binds to a series of rat brain-specific antigens with molecular masses of 150-, 120-, 118-, 106-, 104-, 79-, and 77-kDa. The expression of 3A10 antigens is dependent on the developmental stage of the brain; only the 106-kDa antigen is detected during embryonic stages of rat brain development, while the expression of the remaining 6 antigens starts after birth and reaches a maximum during postnatal days 15-21. Detection of the 3A10 antigens in cultured neuronal and glial cells derived from cerebral cortices of rat brain at embryonic day 18 showed that the 77-, 79-, 106-, and 150-kDa antigens are specifically expressed in neuronal cells. The 77-kDa antigen was purified and identified as synapsin I by amino acid sequence analyses of the peptide fragments isolated after Achromobacter protease I treatment. During the isolation of 3A10-reactive proteins by immunological screening of cDNA libraries constructed from adult rat brain, we found that all of the 3A10-reactive clones contain nucleotide sequences encoding the unique amino acid sequence TRSP(S, R,G)P. Analyses of 3A10-binding to various synthetic peptides showed that the monoclonal antibody recognizes a specific conformational structure formed by either the TRSPXP sequence or similar amino acid sequences that are expressed on a series of developmentally expressed brain proteins.  相似文献   

10.
The distribution of fibronectin in tissues of four human foetuses (7-14 gestation weeks/GW) and twenty seven pig foetuses (25-114 days of gestation) was investigated using immunofluorescence and avidin/biotin methods. Fibronectin was abundant in the circulatory and gastrointestinal system and its derivates, in reticular stroma of immune organs, and in connective tissues and chorionic villi at all developmental stages.  相似文献   

11.
Summary The activity and distribution of y-GT was investigated in a number of organs from human foetuses aged from 14 to 24 weeks post menstruationem. Over this period, enzyme activity increased in the kidney, pancreas and thymus, but decreased in the small intestine. No trend could be established for the liver, although activity was high. In the lung, spleen, brain and adrenals, y-GT was either detectable at very low levels or could not be demonstrated. The possible relationship between y-GT activity in some human tumours and the enzymes level in the corresponding foetal organs is discussed.This work was supported by a grant from the ASFC, SwitzerlandHolder of a Royal Society European Science Exchange Programme Fellowship  相似文献   

12.
Abstract. This study aims to investigate engraftment of human cord blood and foetal bone marrow stem cells after in utero transplantation via the intracoelomic route in the sheep. Here, we performed transplantation in 14 single and 1 twin sheep foetuses at 40–47 days of development, using a novel schedule for injection. (i) Single injection of CD34+ human cord blood stem cells via the coelomic route (from 10 to 50 × 104) in seven single foetuses. (ii) Single injection of CD34+ foetal bone marrow stem cells via the intracoelomic route with further numbers of cells (20 × 105 and 8 × 105, respectively) in three single and in one twin foetuses. (iii) Double fractioned injection (20–30 × 106) via the coelomic route and 20 × 106 postnatally, intravenously, shortly after birth of CD3-depleted cord blood stem cells in four single foetuses. In the first group, three single foetuses showed human/sheep chimaerism at 1, 8 and 14 months after birth. In the second group, the twin foetuses showed human/sheep chimaerism at 1 month after birth. In the third group, only two out of four single foetuses that underwent transplantation showed chimaerism at 1 month. While foetal bone marrow stem cells showed good short-term engraftment (1 month after birth), cord blood stem cells were able to persist longer in the ovine recipients (at 1, 8 and 14 months after birth).  相似文献   

13.
Histochemical studies have been made on the distribution of acetyl- and butyrylcholinesterases (ACHE and BCHE) in various parts of the human and rat brain. Statistical analysis showed that at the 8th week, the highest ACHE activity in the human foetus is observed in the intermediate and plexiform layers of the cerebral cortex. The highest BCHE activity was found in the ependymal layer of various cerebral regions. High BCHE and ACHE activities were noted in the dorsal thalamus and epithalamus. In 10-week human foetuses, total high level of ACHE and BCHE was revealed in various nuclei of the thalamus and subcortical structures of the forebrain (Meynert nucleus, nucleus caudatum). In rats, the highest ACHE activity at the 14th day of prenatal life was found only in subcortical structures of the forebrain. Accumulation of BCHE activity in some of the thalamic nuclei of rats begins at the 10-17th day of postnatal life.  相似文献   

14.
Laminins are the major glycoproteins present in all basement membranes. Previously, we showed that perlecan is present during human development. Although an overview of mRNA-expression of the laminin β1 and β2 chains in various developing fetal organs is already available, a systematic localization of the laminin β1 and β2 chains on the protein level during embryonic and fetal human development is missing. Therefore, we studied the immunohistochemical expression and tissue distribution of the laminin β1 and β2 chains in various developing embryonic and fetal human organs between gestational weeks 8 and 12. The laminin β1 chain was ubiquitously expressed in the basement membrane zones of the brain, ganglia, blood vessels, liver, kidney, skin, pancreas, intestine, heart and skeletal system. Furthermore, the laminin β2 chain was present in the basement membrane zones of the brain, ganglia, skin, heart and skeletal system. The findings of this study support and expand upon the theory that these two laminin chains are important during human development.  相似文献   

15.
We have carried out a comprehensive study of the formation of muscle fibers in the human quadriceps in a large series of well dated human foetuses and children. Our results demonstrate that a first generation of muscle fibers forms between 8-10 weeks. These fibers all express slow twitch myosin heavy chain (MHC) in addition to embryonic and foetal MHCs, vimentin and desmin. Between 10-11 weeks, a subpopulation of these fibers express slow tonic MHC, being the first primordia of muscle spindles. Extrafusal fibers of a second generation form progressively and asynchronously around the primary fibers between 10-18 weeks, giving the muscle a very heterogeneous aspect due to different degrees of organization of their proteins. By 20 weeks, these second generation fibers become homogeneous and thereafter undergo a process of maturation and differentiation when they eliminate vimentin, embryonic and foetal MHCs to express either slow twitch or fast MHC. The differentiation of these second generation fibers into slow and fast depends upon different factors, such as motor innervation or level of thyroid hormone. Around the intrafusal first generation fibers, additional subsequent generations of fibers are also progressively formed. Some differ from the extrafusal second generation fibers by expressing slow tonic MHC, others by continuous expression of foetal MHC. The differentiation of intrafusal fibers is probably under the influence of both sensory and motor innervation.  相似文献   

16.
17.
Summary Carcinoembryonic antigen (CEA) was localized in various embryonic and fetal human tissues between 8 and 16 weeks of gestation as well as in the colorectal mucosa of older fetuses, newborns and adults. Among the embryonic tissues, CEA was always present in the esophagus, the gastric antrum, the duodenum and the rectum. CEA positive staining of bile cannaliculi of the liver was inconstant. All other embryonic tissues were CEA negative. During early fetal development CEA positive staining of the esophagus, antrum and duodenum was inconstant. However, the whole colon became intensively stained. An inconstant CEA specific staining was found in parts of the midgut and in the bile cannaliculi of the liver. The other organs remained CEA negative. Between the 17th week of gestation and birth, CEA staining pattern of the colorectal mucosa did not change. The staining intensity of late fetal colonic mucosa was similar to that of adult colonic mucosa.Deceased 20th August 1982  相似文献   

18.
The indirect immunofluorescence method showed that decreased (in comparison with myoid cells of adult human thymus) content of muscle antigens in the myoid elements of the embryonic organ caused a greater secretory activity of these elements at the early embryogenesis. Due to increased secretory activity of the myoid cells internal medium of the embryonic thymus contained more antigens common to the muscle tissue than the adult human thymus. The fact that during the ontogenesis the functional activity of the myoid cells correlated with the rate of lymphoid tissue formation favours a suggestion that heteroorganic antigens provide the thymus lymphocytes with information concerning the autoantigen structure necessary to induce natural immunological tolerance.  相似文献   

19.
The objective was to study the morphology of the articular disc and analyse the immunohistochemical expression of types I and III collagen markers in the temporomandibular joint (TMJ) disc of human foetuses of different gestational ages. Twenty TMJ from human foetuses supplied by Universidade Federal de Uberaba with gestational ages from 17 to 24 weeks were studied. The gestational age of the foetuses was determined by measuring the crown-rump (CR) length. Macroscopically, the foetuses were fixed in 10% formalin solution and dissected by removing the skin and subcutaneous tissue and exposing the deep structures. Immunohistochemical markers of type I and III were used to characterize the existence of collagen fibres. Analysis of the immunohistochemical markers of types I and III collagen revealed the presence of heterotypical fibril networks.  相似文献   

20.
In the present work we have studied in Neospra caninum aborted bovine foetuses the influence of foetal age (first, second and third gestational periods) on parasite distribution by nested PCR, parasite loads by real-time PCR and N. caninum associated lesions. For this purpose, a total of 220 aborted foetuses were analysed and detection of N. caninum infection was accomplished by nested-PCR in brain, heart and liver, detecting the presence of the parasite in 72 (32.7%) bovine foetuses. When the different age classes were compared, parasite DNA-detectability in heart and liver was reduced over time of gestation (P < 0.05, Fisher F-test). N. caninum distribution, parasite loads and lesions were studied on 34 out of 72 N. caninum-infected foetuses selected according to the stage of pregnancy and organs recovered. A higher number of positive-PCR tissue samples were observed in the foetuses corresponding to the first and second pregnancy periods. In the last trimester, the parasite could only be detected in the brain and, sporadically, in the diaphragm, heart and lymph nodes. The parasite loads decreased during pregnancy and the foetuses from the first period had higher parasite burdens in brain, heart, kidney and lung (P < 0.05, Kruskal-Wallis H-test) than in those corresponding to the other two trimesters of pregnancy. In addition, the observed lesions were more severe in foetuses from the first and second pregnancy periods than those from the third period (P > 0.05, Kruskal-Wallis H-test). Our results confirm the influence of N. caninum foetal age on pathogenesis in natural N. caninum infections.  相似文献   

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