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991.
Liposomes could bind and fuse efficiently to human erythrocytes in the presence of HVJ when they contained gangliosides isolated from human erythrocytes. Sialosylparagloboside, which has a terminal sequence of NeuAcα2?3Ga1β1?4GlcNac, has a much higher receptor activity to the virus than GD1a, GD1b, GT1b, and GT1a, all of which contain the terminal sequence of NeuAcα2?3Galβ1?3GalNAc or NeuAcα2?8NeuAcα2?3Galβ1?3GalNAc. The activity of sialosylparagloboside is comparable to that of glycophorin, a major sialoglycoprotein of human erythrocytes, when compared on the basis of the required amount (as sialic acid) of compounds. The high affinity of sialosylparagloboside to the viral HANA protein is also suggested by the finding that it showed high inhibitory activity against HVJ-mediated binding of glycophorin liposomes to erythrocytes. Sialosylparagloboside was also highly susceptible to the viral sialidase, the other biological function of HANA protein. 相似文献
992.
Blumenfeld Zeev; Dirnfeld Martha; Gonen Yael; Abramovici Haim 《Human reproduction (Oxford, England)》1994,9(2):209-213
To investigate the effect of co-treatment with growth hormone(GH) for ovulation induction with human menopausal gonadotrophins(HMG) on conception, we compared the pregnancy rate and responseto co-treatment with GH versus HMG/human chorionic gonadotrophin(HCG) alone in a prospective, randomized, cross-over protocolof volation induction for either in-vivo or in-vitro fertilization(IVF). The main outcome measures were the amount of gonadotrophinused and conception. Co-treatment with GH was associated witha reduction of 30% in gonadotrophin requirement. In 24 clonidinenegative patients 14 pregnancies were achieved (58.3%) eitherin the GH/HMG/HCG cycle or in the succeeding one. GH co-treatmentdid not generate any pregnancy in eight clonidine positive patients.We conclude that growth hormone may increase the pregnancy ratewhen combined with HMG/HCG for ovulation induction, not onlyin the co-treatment cycle but also in the succeeding one. Thebeneficial, synergistic effect of GH co-treatment was detectedin clonidine negative but not in clonidine positive infertilepatients. 相似文献
993.
A fucose-containing epitope potentially involved in gamete interaction on the human zona pellucida 总被引:2,自引:1,他引:2
Lucas H.; Bercegeay S.; Pendu J.Le; Jean M.; Mirallie S.; Barriere P. 《Human reproduction (Oxford, England)》1994,9(8):1532-1538
The oligosaccharide moiety of human, porcine and bovine zonaepellucidae was studied with lectins and monoclonal antibodiesspecific for tri- or tetra-saccharidic epitopes containing atleast one terminal -L-fucose. Animal eggs were collected fromfollicular aspirates, human eggs were collected from in-vitrofertilization and embryo transfer programmes and pooled intosix groups. By direct immunofluorescence, the lectins reactivitywas detected for the animal or the human zonae pools in thesame way. Reactivity of Aleuria aurantia lectin demonstratedthe presence of L-fucose terminal residues in the zonaefrom the three species studied. By indirect immunofluorescence,the 225 antibody reactivity was detected in every poolof human zonae whereas there was no evidence of any antibodyreactivity on animal zonae. Using an anti-Lewis-b blood groupantibody (225), we observed expression of this antigenas an intrinsic component of the human zona pellucida, independentlyof patients'Lewis red blood cell phenotypes. Antibody 225inhibited the spermatozoa-zona binding in a hemizonaassay, suggesting that this fucose-containing antigen couldbe part of a sperm-zona receptor. 相似文献
994.
Desmin as an immunochemical marker of human decidual cells and its expression in menstrual fluid 总被引:1,自引:0,他引:1
The expression of intermediate filament proteins in human endometrial tissue was examined. Desmin was selectively expressed in decidualized stroma, as demonstrated by SDS-PAGE analysis and positive response with a monoclonal antibody specific for desmin in ELISA and in western blot analysis. The same monoclonal antibody specifically stained human decidual cells in decidualized endometrium (secretory endometrium) in formalin-fixed paraffin-embedded sections prepared from diagnostic curettage samples. Desmin was also detected in menstrual fluid. Therefore, desmin might serve as a biochemical and histochemical marker of human decidualized endometrium. 相似文献
995.
Evidence for the involvement of blood flow-related mechanisms in the ovulatory process of the rat 总被引:7,自引:0,他引:7
Zackrisson U Mikuni M Peterson MC Nilsson B Janson PO Brännström M 《Human reproduction (Oxford, England)》2000,15(2):264-272
To elucidate whether any relationship exists between ovarian blood flow and ovulation rate, the effects on these parameters were examined in equine chorionic gonadotrophin/human chorionic gonadotrophin (eCG/HCG) (15I U/15I U) primed rats after bilateral ligation and severance of either the ovarian branch of the uterine artery and vein (UL), the ovarian artery and vein (OL) or both sites (UL+OL) in comparison to sham operations. Laser Doppler flowmetry demonstrated the presence of microcirculatory vasomotion and a reduction of blood flow after UL, OL and UL+OL performed during the intervals 0-3 h (78, 66 and 19% of pretreatment values respectively) and 6-9 h (68, 57 and 20%) after HCG. Experiments utilizing radioactive microspheres also indicated decreased ovarian blood flow by UL and OL. Ovulation rate was assessed 20 h after HCG in animals where ligations had been performed at 0, 3, 6 and 9 h after HCG. No ovulations were seen after UL+OL and significantly decreased ovulation rates ( approximately 50% of sham operated animals) were seen after UL at 0 and 3 h and after OL at 0, 6 and 9 h. Progesterone concentrations in blood 20 h after HCG were reduced by OL but not UL and ovarian weights were unaffected by ligation. It is concluded that acute blood flow reduction during the ovulatory interval reduces ovulation rate in the rat. 相似文献
996.
Vladimíra Džugasová Margita Obernauerová Katarína Horváthová Mariana Vachová Martina Žáková Július Šubík 《Current genetics》1998,34(4):297-302
The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho
–/rho° mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the β-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA,
is localized in the mitochondria and expressed in response to inositol and choline.
Received: 15 June / 15 July 1998 相似文献
997.
Tucker M.J.; Morton P.C.; Wright G.; Ingargiola P.E.; Sweitzer C.L.; Elsner C.W.; Mitchell-Leef D.E.; Massey J.B. 《Human reproduction (Oxford, England)》1996,11(11):2434-2437
In two separate prospectively randomized trials, intracytoplasmicsperm injection (ICSI) cycles were studied in a controlled mannerto monitor the effects of either bovine oviductal epithelialcell co-culture (n = 119) or assisted hatching by zona drilling(n = 100). In the first study, immediately following ICSI, alleggs were placed directly either onto partial monolayers ofbovine oviductal cells or into regular culture medium. Althoughthe embryo developmental rate was apparently compromised inpart by the presence of the co-culture cells, ultimately therewere no significant differences in either the viable pregnancyrate (31.6% co-culture versus 29.0% control) or the embryonicimplantation rate (11.4% co-culture versus 13.6% control). Assistedhatching also had no significant impact on ICSI cycle outcomein terms of either the viable pregnancy rate (30.0% assistedhatching versus 32.0% control) or the embryonic implantationrate (8.5% assisted hatching versus 13.5% control). However,in female patients aged 235 years, assisted hatching appearedto convey a marginally significant benefit in terms of boththe viable pregnancy rate (35.5% assisted hatching versus 11.1%control) and the embryonic implantation rate (103% assistedhatching versus 3.1 % control). It seems that the overall improvementof ICSI cycle outcome cannot be achieved by the general applicationof either co-culture or assisted hatching. Nevertheless, itis possible that there remain specific patient groups that mightbenefit from selected use of either of these modalities. 相似文献
998.
999.
Sonia Ehrlich Tania Bustos Inder J. Paika Aubrey Milunsky John M. Opitz 《American journal of medical genetics. Part A》1983,15(2):261-263
Some variation in the phenotype of patients with dup(18q) is recognized. Our patient has the phenotype described for dup(18qter). 相似文献
1000.