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91.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
92.
Detection and identification of group B streptococci by use of pigment production 总被引:8,自引:1,他引:8 下载免费PDF全文
Pigment production by group B streptococci (GBS) is a useful test for identification of the organisms. The test is positive in 99.5% of beta-haemolytic strains. No false-positives are noted. Non-haemolytic strains do not produce pigment. Islam's media less agar can be used as a one-step broth detector of GBS in mixed cultures. This may have application for the detection of GBS in women in labour. When used as an identification system for GBS, serum-starch broth can be further modified by reduction of serum and starch concentrations by at least 80%. 相似文献
93.
Lectin affinity chromatography procedures were evaluated for the isolation of enveloped virus glycoproteins. The major glycoprotein of equine infectious anemia virus (E1AV) bound to concanavalin A (Con A)-Sepharose through interactions which could not be reversed by α-methylglucoside, but elution could be accomplished with buffers containing guanidine hydrochloride or sodium dodecyl sulfate. These denaturants, however, also released about one-half of the Con A protein from the Sepharose matrix. This degradation does not appear to have been recognized previously, as denaturants are frequently employed for the isolation of virus glycoproteins from Con A-Sepharose. In contrast, the virus glycoprotein bound equally well to Sepharose-bound Lens culinaris (lentil) lectin affinity columns and was effectively eluted with buffer containing 0.2 M α-methylglucoside. The lentil lectin-Sepharose procedure described is rapid, inexpensive and results in the efficient separation and recovery of EIAV glycoproteins. Thus, lentil lectin-Sepharose can provide a useful alternative to Con A-Sepharose for isolating other high avidity glycoproteins from viral envelopes or cell membranes. 相似文献
94.
Burton C. West Alan S. Rosenthal Nancy A. Gelb Harry R. Kimball 《The American journal of pathology》1974,77(1):41-66
Human blood neutrophilic leukocytes were separated and purified by modifications of the Hypaque/Ficoll and dextran separation methods, resulting in a suspension which was greater than 96% neutrophils. Neutrophils were prepared in 0.34 M sucrose containing heparin and were clarified of nongranular debris by sequential passage through polycarbonate filters of pore size 5 μ and 2 μ. Isopycnic sucrose gradients of such filtrates revealed three major bands. The gradient separated fractions were studied by electron microscopy including peroxidase cytochemistry and by enzyme assay for myeloperoxidase (MPO), β-glucuronidase, muramidase alkaline phosphatase and acid phosphatase utilizing both p-nitrophenylphosphate (pnp) and β-glycerophosphate as substrates. Peroxidase-positive granules were observed at both density 1.22 (band A) and density 1.20 (band B). Three peroxidase-negative granules were identified: the round or oval peroxidase-negative granule of density 1.22 (band A) and two smaller granules, distinguishable by size and shape at density 1.18 (band C). Band C granules contain crystalloid inclusions. Peaks of muramidase activity coincided with bands A and C, suggesting the presence of muramidase in the peroxidase-negative granules of density 1.22 and in one or both of the peroxidase-negative granules at density 1.18. β-Glucuronidase was distributed like MPO, with a major peak in band B and a minor peak in band A. Acid β-glycerophosphatase was largely in band A. Acid pnp phosphatase was nonspecifically associated with soluble nongranular protein which always remained at the origin of sucrose gradients. Alkaline phosphatase was not granule associated and sedimented alone to density 1.145, which is highly suggestive of a cytoplasmic membrane localization for this enzyme. 相似文献
95.
Increased Sensitivity of a New Coagglutination Test for Rapid Identification of Haemophilus influenzae Type b 下载免费PDF全文
Robert J. Grasso Loyd A. West Nikki J. Holbrook Demetrios G. Halkias Lois J. Paradise Herman Friedman 《Journal of clinical microbiology》1981,13(6):1122-1124
A newly developed rapid coagglutination test for identifying Haemophilus influenzae type b organisms isolated from clinical specimens correlated 100% with the slide agglutination test but was 100- to 200-fold more sensitive. 相似文献
96.
Gene expression patterns and gene copy number changes in dermatofibrosarcoma protuberans 总被引:5,自引:0,他引:5 下载免费PDF全文
Linn SC West RB Pollack JR Zhu S Hernandez-Boussard T Nielsen TO Rubin BP Patel R Goldblum JR Siegmund D Botstein D Brown PO Gilks CB van de Rijn M 《The American journal of pathology》2003,163(6):2383-2395
Dermatofibrosarcoma protuberans (DFSP) is an aggressive spindle cell neoplasm. It is associated with the chromosomal translocation, t(17:22), which fuses the COL1A1 and PDGFbeta genes. We determined the characteristic gene expression profile of DFSP and characterized DNA copy number changes in DFSP by array-based comparative genomic hybridization (array CGH). Fresh frozen and formalin-fixed, paraffin-embedded samples of DFSP were analyzed by array CGH (four cases) and DNA microarray analysis of global gene expression (nine cases). The nine DFSPs were readily distinguished from 27 other diverse soft tissue tumors based on their gene expression patterns. Genes characteristically expressed in the DFSPs included PDGF beta and its receptor, PDGFRB, APOD, MEOX1, PLA2R, and PRKCA. Array CGH of DNA extracted either from frozen tumor samples or from paraffin blocks yielded equivalent results. Large areas of chromosomes 17q and 22q, bounded by COL1A1 and PDGF beta, respectively, were amplified in DFSP. Expression of genes in the amplified regions was significantly elevated. Our data shows that: 1) DFSP has a distinctive gene expression profile; 2) array CGH can be applied successfully to frozen or formalin-fixed, paraffin-embedded tumor samples; 3) a characteristic amplification of sequences from chromosomes 17q and 22q, demarcated by the COL1A1 and PDGF beta genes, respectively, was associated with elevated expression of the amplified genes. 相似文献
97.
A comparison was made of the activities of clinical dextran and bradykinin in rats. Chiefly by using antagonists, major differences were identified and the study confirmed that bradykinin is unlikely to play a major role in the dextran anaphylactoid reaction. 相似文献
98.
99.
G B West 《International archives of allergy and applied immunology》1985,78(2):221-223
It is well known that the polysaccharide, dextran, stimulates rat mast cells to undergo histamine secretion, probably by interaction with cell-fixed IgE. Passive sensitisation with antigens greatly enhances histamine release induced in vitro by dextran, and removal of IgE from the cells by acid pH abolishes this release. The importance of IgE antibodies for histamine release from mast cells by agents other than dextran is also well recorded. For example, acetylcholine induces a non-immunological release which is potentiated by the presence of IgE. A link may also exist between cholinergic agents and substance P, a polypeptide which releases histamine by acting on specific receptors and not through interaction with cell-bound IgE. Attempts are made here to gather together some of the physiological and pathological processes involved. 相似文献
100.