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L Savu R Vranckx M Maya E A Nunez 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1987,305(17):627-632
It has been reported evidence based on equilibrium binding, electrophoretic, immunoelectrophoretic studies, that the rat possesses a major high affinity thyroid hormone binding protein, with an electrophoretic mobility and binding properties similar to those of the human thyroxine binding globulin (TBG). It is shown that in the sera of postnatal developing animals, between 3 and 21 days, the thyroxine (T4) and the triiodothyronine (T3) binding activities increase up to 10 times over adult or foetal levels, due to a high transient post-natal surge of the rat TBG. In the adult serum, the TBG persists in decreased amounts: it then yields the predominant role as T4 carrier to the thyroid binding prealbumin (TBPA), but retains the major role as binder of T3, i.e. of the biologically active thyroid hormone. 相似文献
4.
The low molecular weight carbohydrate compositions of the seeds of 29 species ofVicia, namelyV. amoena, V. amurensis, V. bifolia, V. dumetorum, V. fauriei, V. japonica, V. nipponica, V. pisiformis, V. pseudo-orobus,
V. sylvatica, V. unijuga, V. venosa, V. cassubica, V. orobus, V. cracca agg.,V. hirsuta, V. villosa agg.,V. tetrasperma,V. oroboides, V. sepium, V. cuspidata, V. grandiflora, V. lathyloides, V. sativa agg.,V. bithynica, V. faba, V. narbonensis, V. hybrida andV. lutea were determined by gas liquid chromatography. The carbohydrate compositions were found to be species-specific. Principal
component analysis of the carbohydrate composition data showed that these species can be divided into three groups. Although,
as far as the examined species were concerned, these groups were not correlated with the known subgenera, significant correlation
between the groups and the known sections was detected in the subgenusVicia. The carbohydrate composition character would be important to clarify the relationships among closely related taxa of the
genusVicia. 相似文献
5.
L Savu R Vranckx M Maya E A Nunez 《Biochemical and biophysical research communications》1989,159(3):919-926
We use gel equilibration and electrophoretic techniques to compare the binding properties of thyroxine binding globulin and thyroxine binding prealbumin in rat sera. The evidence indicates that TBG bears the serum lowest capacity highest affinity sites for thyroxine (T4) and triiodothyronine (T3) (Ka1 greater than or equal to 10(9) M-1) as well as weaker saturable T3 sites (Ka2 approximately 10(8) M-1). TBPA bears for T4 only Ka2 approximately 10(8) M-1 sites and for T3 only Ka approximately 10(6) M-1 sites. Consistent with these parameters are the specific responses of TBG and TBPA binding activities to varying serum concentrations of T4, T3, oleic acid, the drugs diphenylhydantoin or salicylate. The primary attack of these compounds is aimed at TBG. Small T4, oleate or DPH doses chase the TBG-bound T4 to TBPA, high doses of T4 or oleate but not of DPH inhibiting the T4 binding to both proteins. In the T3-serum interactions, all tested compounds displace the TBG-bound hormone without chasing it to TBPA. The high reactivity of TBG sites designates the protein as crucially involved in modulating the free vs bound serum levels of T4 and T3 against physiological or pathological variations of binding competitors. 相似文献
6.
DNA ploidy pattern and amplification of ERBB and ERBB2 genes in human gastric carcinomas 总被引:1,自引:0,他引:1
N Oda T Tsujino T Tsuda K Yoshida H Nakayama W Yasui E Tahara 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,58(4):273-277
The DNA ploidy pattern and amplification of ERBB and ERBB2 genes were examined in paraffin-embedded tissue from gastric carcinomas using flow cytometry and a slot-blot hybridization technique. The incidence of aneuploidy in well differentiated adenocarcinomas (56%) was significantly higher (p less than 0.05) than that in poorly differentiated adenocarcinomas (21%). The DNA ploidy pattern was not remarkably different between the primary tumors and metastatic deposits in lymph nodes. Of the nine specimens having an aneuploid stem cell line in the primary tumor and/or in metastases, three showed ERBB2 gene amplification and one showed ERBB gene amplification. The incidence of epidermal growth factor (EGF) immunoreactivity in tumor cells showed no difference between diploid and aneuploid tumors. These findings indicate that aneuploidy is frequently associated with amplification of ERBB and ERBB2 genes. 相似文献
7.
Masanori Ito Kazuhiro Yoshida Eikai Kyo Ayse Ayhan Hirofumi Nakayama Wataru Yasui Hisao Ito Eiichi Tahara 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):173-178
We have examined the expression of mRNAs for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-α), EGF
receptor (EGFR), PDGF-A chain (PDGFA), PDGF-B chain (PDGFB) and PDGF receptor (PDGFR) genes in seven human colorectal carcinoma
cell lines and 18 human colorectal carcinomas.
In surgically resected specimens of the 18 colorectal tumors, TGF-α, EGFR, PDGFA, PDGFB and PDGFR mRNAs were detected at various
levels in 15 (83%), 9 (50%), 18 (100%), 8 (44%) and 12 (67%), respectively. They were also detected in normal tissues. Interestingly,
EGF mRNA was detected in only five (28%) of the tumors, but not in normal mucosa. Expression of EGF was also confirmed immunohistochemically
in tumor cells. Of the five tumors expressing EGF, four expressed EGFR mRNA and showed a tendency to invade veins and lymphatics.
All the colorectal carcinoma cell lines expressed TGF-α mRNA, and five cell lines expressed EGFR mRNA simultaneously. Production
of TGF-α protein by DLD-1 and CoLo320DM cells was confirmed by TGF-α specific monoclonal antibody binding assay. The spontaneous3H-thymidine uptake by DLD-1 was suppressed by an anti-TGF-α monoclonal antibody. PDGFA and PDGFB mRNA were also expressed
in four cell lines, but PDGFR and EGF mRNA was not detected. These results suggest that human colorectal carcinomas express
multi-loops of growth factors and that TGF-α produced by tumor cells functions as an autocrine growth factor in human colonic
carcinoma. 相似文献
8.
The structural organization of the cell nucleus was investigated by transmission electron microscopy in the radiosensitive Chinese hamster ovary (CHO) cell mutant, xrs-5 (D0 = 45 cGy), relative to parental K1 cells (D0 = 200 cGy). In 99% of all xrs-5 cells, the outer layer of the nuclear envelope was separated from the inner layer, while 96% of K1 cells had closely apposed layers. This separation of the inner and outer layers of the nuclear envelope in xrs-5 cells was not explained by an increased susceptibility of xrs-5 cells to osmotically induced changes because (1) xrs-5 cells retained the altered nuclear periphery even when several different fixation protocols were used and (2) xrs-5 cells were not more susceptible to cell lysis as measured by trypan blue dye exclusion or by the extracellular presence of lactate dehydrogenase. The difference in the morphological organization in the nuclear periphery of xrs-5 cells correlated with the radiation sensitivity of the cells; xrs-5 cells which spontaneously reverted to a radiation sensitivity similar to that of K1 cells also reverted to a nuclear morphology similar to that of K1 cells. The inner and outer layers of the nuclear envelope were retained in nuclear scaffolds isolated from K1 and xrs-5 cells, indicating that components of the nuclear periphery are part of the nuclear scaffold. These data show that xrs-5 cells have an altered nuclear periphery which correlates with the radiation sensitivity of the cells. The separation of the layers of the nuclear envelope may represent an altered template for repair of DNA damage at the nuclear scaffold and thus may play a role in the defective repair of X-ray-induced DNA double-strand breaks in xrs-5 cells. 相似文献
9.
K Yasui 《American journal of physical anthropology》1986,71(1):39-49
If the visual image and quantitative treatment of a form could be merged, the combination could become a powerful analytical method in morphology. A method is presented for creating an averaged outline. In this method, since the averaged outline is produced statistically, hypothesis testing can be performed on the visual image of the outlines. Intra- and intergroup variation of the outlines can then be assessed by taking allometry into account. This method is applied to the analysis of sexual differences in the midsagittal outline of recent (1880s-1920s) Japanese crania. The averaged outlines of both sexes showed subtle features that could not be detected by traditional measuring techniques. Because the roundness, flatness, or protrusion of specific aspects of the morphology are clearly apparent, sexual differences in this sample could be identified. Changes resulting from allometry did not seem to be present in either sex. The shape distance (DIR) introduced here matched well the visual impression derived from comparisons of the Japanese sample with a Jomon (Neolithic) male and the Broken Hill specimen. 相似文献
10.
Identification of a large interrupted helical domain of disulfide-bonded cartilage collagen 总被引:3,自引:0,他引:3
In order to characterize a larger form of disulfide-bonded cartilage collagen, explants of 17-day embryonic chick sterna were cultured in the presence of [3H] proline. Radioactive collagen chains and fragments that were synthesized and secreted into the culture medium were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography. After limited pepsin digestion of the medium, two discrete disulfide-bonded collagen fragments were detected with Mr = 210,000 and 153,000. These fragments contained 28 and 17.5%, respectively, of the radioactivity in the alpha 1(II)-chains. The smaller fragment (called M) produced three components upon reduction (Mr = 104,000, 51,000, and 31,000) and seemed to represent the previously reported collagens, HMW and M1. The larger fragment (called N) has not been previously described and gave rise to three components upon reduction (Mr = 140,000, 69,000, and 49,000). Prolonged pepsin treatment resulted in the gradual decrease of N with a corresponding increase of M, suggesting the conversion of N to M. CNBr peptide mapping demonstrated that all M-derived peptides were present in N and that N contained extra peptides that account for its larger size. These observations suggest that N represents a larger more intact form of cartilage-derived disulfide-bonded collagen. 相似文献