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61.
A radioimmunoassay for 3 beta-hydroxy-5-cholenoyl glycine in human urine has been developed. The antiserum was elicited with the antigen in which the steroid hapten is linked to a bovine serum albumin through the C-19 position. The [125I]-tyrosine derivative of the hapten was used as radioligand. The standard curves were linear ranging from 10 to 320 ng/mL. The cross-reactivities with other bile acids were not detectable and below 0.3% with cholesterol. Sample preparation includes extraction of 3 beta-hydroxy-5-cholenoyl glycine from urine and solvolysis of the sulfates--main form present in urine. Urinary excretion of 3 beta-hydroxy-5-cholenoyl glycine was 0.373 +/- 0.133 mumol/day in healthy adults. Urinary excretion of 3 beta-hydroxy-5-cholenoyl glycine increased in chronic liver dysfunction, hepatoma and obstructive jaundice in this order. 相似文献
62.
Amylase in human lungs and the female genital tract. Histochemical and immunohistochemical localization 总被引:2,自引:0,他引:2
We investigated the localization of amylase in normal human lungs and the female genital tract using immunohistochemical and histochemical methods. Immunohistochemical procedures were applied to formaldehyde-fixed, paraffin-embedded specimens as well as to cryostat sections of periodate/lysine/paraformaldehyde (PLP)-fixed tissues. The starch-substrate-film method was used for the histochemical investigation of unfixed frozen sections. Amylase immunoreactivity was observed in ciliated epithelial cells of the bronchus and in serous cells of the bronchial glands but not in the alveolar epithelium. Immunoreactive amylase was also found in the cytoplasm of the ciliated epithelium of the fallopian tubes, especially in the apical part of the cytoplasm and in ciliary vesicles. Immunoreactive amylase was also found to be present in the surface epithelial cells and glands of the uterine cervix, as well as in the superficial part of the endometrial glands. The distribution of amylase activity revealed using histochemistry was similar to that observed in cryostat sections of PLP-fixed tissues after immunohistochemical staining. Amylase antigenicity was better preserved in cryostat sections of PLP-fixed materials than in formaldehyde-fixed, paraffin-embedded specimens. The results are discussed in relation to pulmonary and female-genital-tract diseases. 相似文献
63.
Tatsuo Motokawa 《Zoomorphology》1986,106(4):247-253
Summary Morphology and movement of the spines of Acanthaster planci were studied. All surfaces of the animal are covered with spines. The spines on the aboral surface are cylindrical with sharp tips. The spines on the oral surface are flat; they bend over to cover the mouth and the ambulacral grooves when these soft parts are stimulated. Those on the side of the animal make a barrier of crossed spines. Thus the structure and movement of the spines are well-adapted for defense.The junction between the primary aboral spine and its pedicel makes a movable joint. The ultrastructure of the connective tissue at the joint was studied. The connective tissue is mainly composed of collagen fibers. Presumed neurosecretory cells with processes which are filled with electron-dense granules of 0.2 m diameter were found between collagen fibers. Muscle fibers are mainly found in the connective tissue at the central holes. These observations support the view that the joint connective tissue has catch properties. 相似文献
64.
T Makino K Nakazawa K Ishii I Haginiwa A Nakayama R Iizuka 《Endocrinologia japonica》1983,30(3):389-395
Freshly obtained human placentas from various periods of gestation were quantitatively analysed for their immunoreactive oxytocin (OT) content and its biological activity was examined in a Magnus apparatus by utilizing rat uterus. The mean values for placental immunoreactive OT per gram tissue increased from the first to the second trimester, maintaining its high level to term. The total content of placental OT also increased continually from the beginning of pregnancy to term. Blood levels of estrogen stimulated neurophysin (ESN) and OT were concomitantly enhanced through gestation. Placental extract and synthetic OT showed similar peaks in the elution pattern of ion-exchange chromatography through a carboxymethyl cellulose column. Synthetic OT and placental extract induced marked uterine contraction in diestrous rats. However placental extract previously incubated with OT antiserum failed to induce this effect. Though detection of immunoreactive OT by immunoassay alone does not provide definite identification of pituitary and placental OT, the present study suggests that placental immunoreactive OT could have a contracting effect on the uterine muscle. 相似文献
65.
66.
Metabolism of 9-(1,3-dihydroxy-2-propoxymethyl)guanine, a new anti-herpes virus compound, in herpes simplex virus-infected cells 总被引:18,自引:0,他引:18
Y C Cheng S P Grill G E Dutschman K Nakayama K F Bastow 《The Journal of biological chemistry》1983,258(20):12460-12464
The metabolism of 9-(1,3-dihydroxy-2-propoxymethyl)guanine (DHPG), one of the most promising new anti-herpes virus compounds, in HeLa cells infected with herpes simplex virus type 1 was compared with that in the uninfected HeLa cells. In the virus-infected cells, the uptake of DHPG was enhanced and the major metabolites were found to be the mono-, di-, and triphosphate derivatives. The formation of these metabolites was dependent on the extracellular concentration of DHPG (0.5 to 5.0 microM). Virus-induced thymidine kinase was capable of phosphorylating DHPG to its monophosphate which could be further phosphorylated to the di- and triphosphate derivatives by the host cellular enzymes. Incorporation of the DHPG into DNA was observed in virus-infected cells. In contrast with 9-(2-hydroxyethoxymethyl)guanine, DHPG seemed not to serve as a chain terminator, but to be incorporated internally into DNA strands. 相似文献
67.
The preparation and antigenic property of 3 beta-hydroxy-5-cholen-24-oic acid-bovine serum albumin (BSA) conjugate in which the hapten is linked to the carrier protein through an (O-carboxymethyl) oxime bridge at the C-19 position on the steroid nucleus is described. Antibody raised against antigen in the rabbit possessed high titer and specificity to 3 beta-hydroxy-5-cholen-24-oic acid, exhibiting no significant cross-reactions with various bile acids. 相似文献
68.
Dichroism of bacteriochlorophyll in cells of the photosynthetic bacterium Rhodopseudomonas palustris
1. The dichroism was measured at varied wavelengths of polarized light in “intact” cells of Rhodopseudomonas palustris and in films of air-dried lamellar fragments of the bacterium. 相似文献
69.
70.
Inhibition of Thiamine Pyrophosphate Utilization by Thiamine or Its Monophosphate in Escherichia coli
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The growth of a thiamine pyrophosphate auxotroph of Escherichi coli was inhibited by either thiamine or thiamine monophosphate, and the growth of a thiamine monophosphate auxotroph was inhibited by thiamine. The thiamine pyrophosphate-dependent oxidation of pyruvate was inhibited by thiamine with whole cells of the thiamine pyrophosphate auxotroph but not with cell extracts prepared from the same organism. In addition, the thiamine pyrophosphate uptake of the thiamine pyrophosphate auxotroph was inhibited by either thiamine or thiamine monophosphate. Although the thiamine pyrophosphate uptake of a revertant, selected for prototrophy from the thiamine monophosphate auxotroph, was inhibited by thiamine to an extent comparable to that observed with the thiamine monophosphate auxotroph, its growth was no longer inhibited by thiamine. A possible mechanism for the inhibition by thiamine and thiamine monophosphate in the utilization of thiamine pyrophosphate is discussed. 相似文献