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1.
Ovarian steroids and growth factors are intragonadal modulators which augment a key endpoint of follicle-stimulating hormone (FSH) action in granulosa cells: the induction of aromatase activity. Studies of these paracrine hormones that enhance FSH-stimulated estrogen biosynthesis by cultured rat granulosa cells, have led to the development of a sensitive and specific
bioassay for FSH. This newly developed granulosa cell aromatase bioassay (GAB) allows for the measurement of bioactive FSH levels in serum and urine of humans and animals with various physiological and pathological conditions. These studies have demonstrated that the GAB assay is useful in detecting possible changes in the molecular forms of FSH. The adaptation of this method for urine samples allows for the measurement of bio-FSH levels in situations where venipuncture is not practical or in species for which specific radioimmunoassays are not available. 相似文献
2.
Summary C-band polymorphisms of chromosome 1 can be quantified by Ce bands visualized using oblique epi-illumination. In this paper the polymorphic region of chromosome 9, including variants such as 9qh+, inversions, and translocations, was analyzed in a total of 1860 chromosomes from 20 individuals and 8 fetuses. In this sample we found between zero and five Ce bands on 9q and between zero and four Ce bands on 9p with a maximum of five Ce bands per chromosome. On the basis of these observations at least 19 different polymorphic patterns can be expected theoretically, 15 of which were observed in our sample. Among these, five polymorphic Ce-band classes were distinguishable by the method presented. Considering both homologues, 52=25 quantitatively discernible chromosome 9 pairs may exist. 相似文献
3.
One of the most widely used mechanisms by which the role of glutathione (GSH) in cellular functions has been withdrawn, is to deplete GSH intracellularly. The importance of the procedure and xenobiotic chosen to get it is discussed. Mitochondrial GSH plays certainly an important role in maintaining cellular homeostasis. This contribution varies depending on the tissue and the conclusions obtained about the functions of this GSH pool in one organ may not be applied to others. Original data on the subcellular distribution of GSH in myocardial tissue of the rat are presented, and the effect of phorone on both cardiac GSH pools is compared with the effect in liver. The mechanical failure of myocardium after ischemic or reperfusion damage might involve mitochondrial GSH, in view of the literature data referring to the role of thiol groups in energy transfer from mitochondria to cytosol. 相似文献
4.
Enzyme immunoassay of oestrogen and progesterone receptors in uterine and intrauterine tissue during human pregnancy and labour 总被引:4,自引:0,他引:4
T Padayachi R J Pegoraro L Rom S M Joubert 《The Journal of steroid biochemistry and molecular biology》1990,37(4):509-511
Oestrogen and progesterone receptors were studied in the non-pregnant state, in early pregnancy and at term using monoclonal antibody enzyme immunoassays. Receptors for both steroids were found in tissues from non-pregnant patients and patients in early pregnancy. At term oestrogen receptors were undetectable in all tissues studied. Progesterone receptors were undetectable in chorion, amnion and placenta at term, while present in extremely low concentrations in decidua and myometrium. 相似文献
5.
S Natarajan E M Gordon E F Sabo J D Godfrey H N Weller J Pluscec M B Rom J Engebrecht D W Cushman J M Deforrest 《Journal of enzyme inhibition》1988,2(2):91-97
The design rationale for a new series of tripeptide derived angiotensin converting enzyme (ACE) inhibitors, which we term "ketomethylureas", is described. Analogs of tripeptide substrates (i.e. N-benzoyl-Phe-Ala-Pro) in which the nitrogen atom of the scissile amide bond and the adjacent asymmetric carbon atom of the penultimate amino acid residue are formally transposed give rise to this novel class of inhibitors. The most potent ketomethylureas inhibit ACE with I50 values in the nM range. 相似文献
6.
Uri Werner Edith Suss-Toby Ayelet Rom Baruch Minke 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1992,170(4):427-434
Summary Illumination of barnacle (Balanus amphitrite) photoreceptors is known to increase the membrane permeability to sodium and Ca2+ ions resulting in a depolarizing receptor potential. In this report, we show that lanthanum (La3+), a known inhibitor of Ca-binding proteins, reversibly eliminates the receptor potential of barnacle photoreceptors when applied to the extracellular space. Similar reversible elimination of the light response was obtained by removing extracellular Ca2+ by application of the calcium chelating agent EGTA. Iontophoretic injection of Ca2+, but not K+ into the cells protected both the transient and the steady-state phases of the receptor potential from elimination by EGTA while only the transient phase was protected in the presence of La3+. The EGTA experiments suggest that internal Ca2+ is necessary for light excitation of barnacle photoreceptors while the La3+ experiments suggest that La3+-sensitive inward current is necessary to maintain excitation during prolonged light.Abbreviations EGTA
ethylenglyol-bis-(-aminoethylether) N, N, N1, N1-tetraacetate
- BAPTA
bis-(0-aminophenoxy)-ethane-N, N, N1, N1-tetraacetic acid
- DMSO
dimethyl sulfoxide
- trp
transient receptor potential
- nss
no steady state
- ASW
artificial sea water 相似文献
7.
Maria L. Boccia Martin L. Reite Kristine Kaemingk Polly Held Mark L. Laudenslager 《Primates; journal of primatology》1991,32(2):255-263
The social environment affects both behavioral and physiological responses to separation from the mother. Less information
is available on the impact of the social environment on the response to separation in peer-reared infant monkeys. This study
reports the responses of peer-reared pigtail macaque infants to repeated separations, and the impact of social versus isolation
housing during the separation. The responses of two pairs of monkeys were studied during four three-day separations. One of
each pair was housed in isolation during the separation, and the other was with another pair of peers, with whom they had
been living for one month prior to the separation. The isolation-housed peer responded to the separation with behavioral agitation,
but no depression. The socially-housed peer's behavior did not differ from baseline during the separation. During successive
reunions, all the separated monkeys, regardless of housing condition, exhibited declining levels of behaviors related to maintaining
proximity to their attachment figure. Although the number of subjects is small, the results suggest that the presence of social
support, in the form of a familiar peer, can ameliorate the response to separation, and that with repeated separations the
responses of the monkeys changes significantly. 相似文献
8.
Isolation of cDNA clones and complete amino acid sequence of human erythrocyte glycophorin C 总被引:7,自引:0,他引:7
Y Colin C Rahuel J London P H Roméo L d'Auriol F Galibert J P Cartron 《The Journal of biological chemistry》1986,261(1):229-233
Two cDNA clones for glycophorin C, a transmembrane glycoprotein of the human erythrocyte which carries the blood group Gerbich antigens, have been isolated from a human reticulocyte cDNA library. The clones were identified with a mixture of 32 oligonucleotide probes (14-mer) which have been synthetized according to the amino acid sequence Asp-Pro-Gly-Met-Ala present in the N-terminal tryptic peptide of the molecule. The primary structure of glycophorin C deduced from the nucleotide sequence of the 460 base-pair insert of the pGCW5 clone indicates that the complete protein is a single polypeptide chain of 128 amino acids clearly organized in three distinct domains. The N-terminal part (residues 1-57, approximately) which is N- and O-glycosylated is connected to a hydrophilic C-terminal domain (residues 82-128, approximately) containing 4 tyrosine residues by a hydrophobic stretch of nonpolar amino acids (residues 58-81, approximately) probably interacting with the membrane lipids and permitting the whole molecule to span the lipid bilayer. Northern blot analysis using a 265-base-pair restriction fragment obtained by DdeI digestion of the inserted DNA shows that the glycophorin C mRNA from human erythroblasts is approximately 1.4 kilobases long and is present in the human fetal liver and the human K562 and HEL cell lines which exhibit erythroid features. The glycophorin C mRNA, however, is absent from adult liver and lymphocytes, indicating that this protein represents a new erythrocyte-specific probe which might be useful to study erythroid differentiation. 相似文献
9.
Cloning and sequencing of mRNAs coding for two adult alpha globin chains of the salamander Pleurodeles waltlii 总被引:1,自引:0,他引:1
A cDNA library of erythrocyte mRNAs was established from immature red blood cells of the adult amphibian, Pleurodeles waltlii (urodele; salamander). The cDNA clones corresponding to the four adult globin chains were first identified and characterized by positive selection and the cDNAs derived from the two (major and minor) alpha-globin chains sequenced. The sequences presented contain both the complete 3'-noncoding region and the coding region of both chains, with the exception of the first nine codons of the minor alpha-chain, and a portion of the 5'-noncoding region of the major chain. The amino acid sequences of the encoded alpha-globin polypeptides have been deduced and compared with those of Xenopus laevis and of man. These comparative studies suggest that the alpha-globins of Pleurodeles waltlii and Xenopus laevis may have diverged from a common ancestral gene at the time when mammalian and amphibian lines diverged, and that they then evolved separately. Duplication of the alpha-gene, which is responsible for the polypeptide heterogeneity, appears to have occurred earlier in Pleurodeles waltlii than in Xenopus laevis. 相似文献
10.
Emilio Román Galán Jaun A. Galbis Pérez Mariá A. Arévalo Arévalo 《Carbohydrate research》1983,116(2):255-262
The reaction between 2-(benzylamino)-2-deoxy-d-glycero-l-gluco-heptose and 5,5-dimethyl-1,3-cyclohexanedione yields 1-benzyl-4,5,6,7-tetrahydro-6,6-dimethyl-2-(d-galacto-pentitol-1-yl)-indol-4-one (2). Acid-catalyzed, intramolecular dehydration of 2 under kinetically controlled conditions gives 1-benzyl-4,5,6,7-tetrahydro-2-α-d-lyxofuranosyl-6,6-dimethylindol-4-one; the anomeric configuration of this compound is only suggested. When the dehydration reaction is conducted under thermodynamically controlled conditions, it produces a 1:1 mixture of the α- and β-d-lyxopyranosyl compounds. The structures of the new compounds were elucidated by chemical and physical methods. 相似文献