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81.
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83.
Uterus didelphys is a rare congenital abnormality of the reproductive tract. Although it occurs in various species, there are no published reports describing pregnancy outcome in association with this abnormality. Herein we describe a case of successful unilateral singleton pregnancy in a ewe incidentally found to have uterus didelphys during the course of a biomedical research study. The pregnancy was established using assisted reproductive techniques and interrupted in late gestation, at which point the abnormality was identified. Serial ultrasound assessment of foetal biometry revealed a normal foetal growth trajectory. Despite a 45% reduction in placentome number, total placentome weight was near normal secondary to compensatory placentome growth and development. To our knowledge, this is the first detailed report of normal foetal growth in an animal with uterus didelphys and illustrates the ability of the ovine placenta to adapt to a reduced number of placentomes and maintain foetal nutrient supply. 相似文献
84.
Hillwig ML Hammer KD Birt DF Wurtele ES 《Journal of agricultural and food chemistry》2008,56(12):4359-4366
In this paper we characterize the metabolic fingerprint and first reported anti-inflammatory activity of Hypericum gentianoides. H. gentianoides has a history of medical use by Native Americans, but it has been studied very little for biological activity. High-performance liquid chromatography (HPLC) and liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analyses of a methanol extract show that H. gentianoides contains a family of over nine related compounds that have retention times, mass spectra, and a distinctive UV absorption spectra characteristic of certain acyl-phloroglucinols. These metabolites are abundant relative to other secondary products present in H. gentianoides, accounting for approximately 0.2 g per gram of dry plant tissue. H. gentianoides methanol extracts and a specific semipreparative HPLC fraction from these extracts containing the putative acyl-phloroglucinols reduce prostaglandin E 2 synthesis in mammalian macrophages. 相似文献
85.
C Almiñana MA Gil C Cuello I Caballero J Roca JM Vazquez EA Martinez 《Reproduction in domestic animals》2008,43(6):747-752
The present study was designed to evaluate three different in vitro fertilization (IVF) systems: a straw‐IVF system with 10 min of coincubation, a straw‐IVF system with 6‐h coincubation and the microdrop‐IVF system with 6‐h coincubation (the traditional IVF system used routinely in most of IVF laboratories) in an attempt to reduce polyspermic penetration ( Experiment 1 ). When the straw‐IVF system was tested in combination with two coincubation times, the use of 10 min of coincubation significantly increased (p < 0.001) the penetration rate and the efficiency of fertilization (67.7 ± 6.4% vs 31.9 ± 6.5% and 41.5 ± 2.5% vs 17.6 ± 2.5% for 10 min and 6 h, respectively), while there were no significant differences in the incidence of monospermy between both systems (64.3 ± 5.1% and 67.7 ± 3.4%, for 10 min and 6 h, respectively). The penetration rate in the 6‐h microdrop‐IVF system was higher (93.8 ± 3.6%; p < 0.001) compared with the 10‐min straw‐IVF system (67.7 ± 6.4%), however, monospermy was severely reduced (25.0 ± 4.3% vs 67.7 ± 3.4%, for the 6‐h microdrop‐IVF system and 10‐min straw‐IVF system, respectively). The efficiency of the IVF showed similar values between microdrop and 6‐h straw‐IVF systems, but efficiency was significantly improved (p < 0.05) when the 10‐min straw‐IVF system was used. Experiment 2 was designed to compare porcine in vitro embryo production in two IVF systems, the 6‐h microdrop‐IVF system (1000 sperm per oocyte) and 10‐min straw‐IVF system (30 000 sperm per oocyte). The blastocyst formation rates tended (p = 0.06) to be higher when the 10‐min straw‐IVF system was used compared with the 6‐h microdrop‐IVF system. In addition, the number of total cells per blastocyst increased significantly (p < 0.05) in the 10‐min straw‐IVF system. These results showed that the 10‐min straw‐IVF system is an effective way to decrease polyspermic penetration, and improve the efficiency of fertilization and the quality of blastocysts in terms of cell number per embryo. 相似文献
86.
87.
To validate the use of the tissue microarray (TMA) method for immunophenotyping of ferret lymphomas, a TMA was constructed containing duplicate 1-mm cores sampled from 112 paraffin-embedded lymphoma tissue specimens obtained from 43 ferret lymphoma cases. Immunohistochemical (IHC) expression of CD3, CD79alpha, and Ki-67 (MIB-1) was determined by TMA and whole mount (WM) staining of each individual case for result comparison. There was a high correlation between CD79alpha and CD3 results comparing ferret TMA and WM sections (kappa statistic 0.71-0.73 for single-core TMA and 0.79-0.95 for duplicate-core TMA) and between continuous data from Ki-67 staining of ferret TMA sections and WM sections (concordance correlation coefficients 0.77 for single cores and 0.87 for duplicate cores). Subsequently, a panel of commercially available antibodies was applied to the TMA for the analysis of expression in ferret lymphomas. The results of this study confirmed previously published results suggesting specific cross-reactivity of the applied IHC markers (CD3, CD79alpha, Ki67) with ferret lymphoma tissue. Other IHC markers (CD45Ro, bcl2, bcl10, MUM1, CD30, vimentin) were also expressed in subsets of the included ferret lymphomas. Further studies are necessary to determine the usefulness of these markers for diagnostic and prognostic evaluation of ferret lymphomas. In conclusion, the TMA technology was useful for rapid and accurate analysis of protein expression in large archival cohorts of ferret lymphoma cases. 相似文献
88.
A.C. Zeven K.J. Dehmer T. Gladis K. Hammer H. Lux 《Genetic Resources and Crop Evolution》1998,45(2):105-111
A collection of vegetatively propagated perennial kales (Brassica oleracea L. var. ramosa DC., 64 accessions in total), predominantly from the Netherlands, was subjected to RAPD analysis in order to confirm or reject the presence of possible duplicates as indicated by isozyme and cytological data, as well as by morphological data described here. By employing 9 decamer primers, seven RAPD patterns could be attributed to almost all of the respective accessions, with up to 22 clones exhibiting identical features for the parameters examined. By these results, a high percentage of duplication is very strongly indicated in the collection, offering possibilities for a reduction in the number of clones to be propagated. The highest level of genetic variation was found in two kales from Portugal, which differed significantly from the other accessions. 相似文献
89.
W Zhou JM Thomas DS Shephard BFG Johnson D Ozkaya T Maschmeyer RG Bell Q Ge 《Science (New York, N.Y.)》1998,280(5364):705-708
The anionic ruthenium cluster carbonylates [Ru6C(CO)16]2- or [H2Ru10(CO)25]2- interspersed with bis(triphenylphosphino)iminium counterions (PPN+) are incorporated from solution into the pores of MCM-41 mesoporous silica (3 nanometers in diameter), where they form tightly packed arrays. These arrays were shown by high-resolution transmission electron microscopy, Fourier transform optical diffraction, and computer simulations to be well ordered both along and perpendicular to the axis of the cylindrical pores. In their denuded state produced by gentle thermolysis, the cluster carbonylates yield nanoparticles of ruthenium that are less well ordered than their assimilated precursors but show good activity as hydrogenation catalysts for hexene and cyclooctene. In both their as-prepared and denuded states, these encapsulated clusters are likely to exhibit interesting electronic and other properties. 相似文献
90.
Are extinctions of marine vertebrates as rare and unlikely as current data indicate? Long-term research surveys on the continental shelf between the Grand Banks of Newfoundland and southern New England reveal that one of the largest skates in the northwest Atlantic, the barndoor skate (Raja laevis), is close to extinction. Forty-five years ago, research surveys on St. Pierre Bank (off southern Newfoundland) recorded barndoor skates in 10% of their tows; in the last 20 years, none has been caught, and this pattern of decline is similar throughout the range of the species. 相似文献