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Olfactory tissues from human fetuses (17.5-28 weeks of gestation) were stained by immunofluorescence for neural cell adhesion molecules (N-CAMs). Staining for N-CAMs was most prominent in the olfactory nerve bundles in the lamina propria, while in the olfactory epithelium, it was present on the olfactory receptor neurons and globose basal cells. The basal cells proper and supporting cells lacked N-CAMs. In the olfactory bulb, only the olfactory nerve and glomerular layers showed moderate labeling for N-CAMs. Western blot analysis showed that the N-CAMs of the fetal human primary olfactory pathway consisted of three molecular isoforms, N-CAM180, N-CAM140 and N-CAM120. 相似文献
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Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation 总被引:9,自引:4,他引:9
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and
iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated
silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by
gradient centrifugation for use in assisted reproductive procedures.
Efficacy was assessed in terms of percentages of sperm recovery, sperm
vitality and motility, normal sperm morphology and normal sperm chromatin
condensation. No significant difference was found in the recovery of
spermatozoa for men with both normal sperm counts and oligozoospermia,
between PVP-coated and silane-coated particle solutions. Iodixanol had
significantly lower sperm recovery compared to the other products. Sperm
vitality, progressive motility, normal morphology and normal chromatin
condensation did not differ significantly between any of the sperm
isolation products.
相似文献
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Tan PH Jayabaskar T Chuah KL Lee HY Tan Y Hilmy M Hung H Selvarajan S Bay BH 《American journal of clinical pathology》2005,123(4):529-540
We aimed to establish whether morphologic parameters were prognostically important in a large series of breast phyllodes tumors in Asian women. Of 335 phyllodes tumors diagnosed at the Department of Pathology, Singapore General Hospital, Singapore, between January 1992 and December 2002, 250 (74.6%) were benign, 54 (16.1%) borderline, and 31 (9.3%) malignant, based on histologic review of archival slides. Of the women, 43 (12.8%) experienced recurrences during the follow-up period. Recurrent disease was correlated with grade or classification (P = .028), stromal atypia (P = .016), stromal hypercellularity (P = .046), and permeative microscopic borders (P = .021). Multivariate analysis revealed that independent predictors of recurrence were pseudoangiomatous stromal hyperplasia (PASH) and margin status, whereby the presence of PASH and complete or negative margins reduced recurrence hazards by 51.3% and 51.7% respectively. The 7 women who died of disease during follow-up had malignant phyllodes tumor at the outset and experienced recurrences, and death was preceded by distant metastases. 相似文献
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Light microscopic observations indicated that cellular differentiation of the primary olfactory pathway in human fetuses was relatively advanced by the end of the first trimester. However, immunohistochemical staining showed that olfactory marker protein was present in the receptor cells only at about 28 weeks post-conception. At about 32 weeks, modest amounts of the protein could be found in the peripheral olfactory nerve layer and a few glomeruli, with increased staining observed in subsequent weeks. The results show conclusively that human fetal olfactory neurons synthesize olfactory marker protein during the later half of gestation. 相似文献
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Morphological and functional plasticity of olfactory ensheathing cells 总被引:12,自引:0,他引:12
In the primary olfactory pathway, olfactory ensheathing cells (OECs) extend processes to envelop bundles of olfactory axons
as they course towards their termination in the olfactory bulb. The expression of growth-promoting adhesion and extracellular
matrix molecules by OECs, and their spatially close association with olfactory axons are consistent with OECs being involved
in promoting and guiding olfactory axon growth. Because of this, OECs have been employed as a possible tool for inducing axonal
regeneration in the injured adult CNS, resulting in significant functional recovery in some animal models and promising outcomes
from early clinical applications. However, fundamental aspects of OEC biology remain unclear. This brief review discusses
some of the experimental data that have resulted in conflicting views with regard to the identity of OECs. We present here
recent findings which support the notion of OECs as a single but malleable phenotype which demonstrate extensive morphological
and functional plasticity depending on the environmental stimuli. The review includes a discussion of the normal functional
role of OECs in the developing primary olfactory pathway as well as their interaction with regenerating axons and reactive
astrocytes in the novel environment of the injured CNS. The use of OECs to induce repair in the injured nervous system reflects
the functional plasticity of these cells. Finally, we will explore the possibility that recent microarray data could point
to OECs assuming an innate immune function or playing a role in modulating neuroinflammation. 相似文献