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101.
Hanley PW Baze WB McArthur MJ Bernacky BJ Wilkerson GK Barnhart KF 《Comparative medicine》2012,62(3):229-233
A 10-y-old multiparous rhesus macaque presented for an annual routine physical examination. Clinically, the animal had pale mucous membranes, petechial and ecchymotic hemorrhages in multiple sites, and a laceration at the tail base. Severe pancytopenia was noted on hematologic evaluation. The monkey was seronegative for SIV, simian T-lymphotropic virus, simian retrovirus type D, and Macacine herpesvirus 1. Bone marrow evaluation revealed a paucity of megakaryocytic precursors in a hypercellular marrow with marked erythroid hyperplasia. In light of these findings, the diagnosis was acquired amegakaryocytic thrombocytopenia purpura. Due to the poor prognosis of the syndrome and clinical deterioration of the monkey, euthanasia was elected. A definitive cause of the thrombocytopenia was not identified; however, the syndrome may have developed secondary to a recent spontaneous abortion. To our knowledge, this case represents the first reported observation of acquired amegakaryocytic thrombocytopenia purpura in a rhesus monkey. 相似文献
102.
Biologic drugs, such as monoclonal antibodies, are commonly made using mammalian cells in culture. The cell lines used for manufacturing should ideally be clonal, meaning derived from a single cell, which represents a technically challenging process. Fetal bovine serum is often used to support low cell density cultures, however, from a regulatory perspective, it is preferable to avoid animal‐derived components to increase process consistency and reduce the risk of contamination from adventitious agents. Chinese hamster ovary (CHO) cells are the most widely used cell line in industry and a large number of serum‐free, protein‐free, and fully chemically defined growth media are commercially available, although these media alone do not readily support efficient single cell cloning. In this work, we have developed a simple, fully defined, single‐cell cloning media, specifically for CHO cells, using commercially available reagents. Our results show that a 1:1 mixture of CD‐CHO? and DMEM/F12 supplemented with 1.5 g/L of recombinant albumin (Albucult®) supports single cell cloning. This formulation can support recovery of single cells in 43% of cultures compared to 62% in the presence of serum. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012 相似文献
103.
Developmental and environmental induction of Lea and LeaA mRNAs and the postabscission program during embryo culture. 总被引:11,自引:4,他引:11 下载免费PDF全文
The major programs of gene expression during late embryogenesis are the muturation or reserve accumulation program and, after ovule abscission, the postabscission program that is composed largely of Lea and LeaA mRNAs that probably encode desiccation protectants. There are diverse opinions about the developmental regulators of these programs. Several candidates are evaluated here by measuring, in cultured embryos, the accumulation kinetics of cloned mRNAs specifically expressed in the normal maturation, postabscission, or germination programs of cotton. Maturation-stage embryos both terminate the maturation program and induce the postabscission program after excision and culture, just as they do later in the plant after ovule abscission. However, they also induce simultaneously the germination program and are thus different from any normal stage of embryo development or germination. The developmental induction of the postabscission program in culture does not require exogenous abscisic acid, but its expression is enhanced by precocious desiccation or culture on abscisic acid or high osmoticum, probably by an environmentally responsive mechanism that normally operates during germination. Normal desiccation does not control any of these programs because the embryo acquires all of the characteristics of a mature embryo before it desiccates. These and other results suggest regulation of normal embryogenesis by a maternal maturation factor, a postabscission factor, and the postabscission program. 相似文献
104.
IE Hughes 《BioEssays : news and reviews in molecular, cellular and developmental biology》1999,21(11):980-981
Instant Pharmacology (1999). Saeb-Parsy K, Assomull RG, Kahn FZ, Saeb-Parsy K, and Kelly E. John Wiley and Sons 349 pp. £19.99 pbk; ISBN 0471976393 © 1999 John Wiley & Sons, Inc. 相似文献
105.
The organogenesis of the soleus muscle of the 129 ReJ mouse (a mixed muscle, which in the adult contains approximately equal numbers of slow-twitch oxidative and fast-twitch oxidative-glycolytic myofibers) was studied in spaced, serial transverse, and longitudinal sections of muscles of 14-, 16-, and 18-day in utero and 1- and 5-day postnatal mice. A discrete soleus muscle was distinguished by 14 days in utero. It consisted of groups of closely apposed primary myotubes displaying junctional complexes and a pleomorphic population of mononucleated cells. Between 14 and 16 days in utero there was little de novo myotube formation. At 16 days in utero, basal lamina surrounded groups of primary myotubes; and primitive motor endplates were found on these myotubes. At 18 days in utero, the basal-lamina-enclosed groups of primary myotubes were no longer present. At this stage, basal lamina surrounded clusters (consisting of one primary myotube and one or more secondary myotubes) or independent myotubes (single myotubes surrounded by their own basal lamina). Cluster formation and cluster dispersal occurred concurrently, beginning at 18 days in utero and extending until birth. At birth, there was still a substantial population of immature, secondary myotubes that interdigitated with larger, more mature primary myofibers. At this stage, intermuscular axons had begun to myelinate, and postsynaptic specialization of the motor endplates had begun. Cluster dispersal and myonuclear migration was completed during the first 5 days postnatally with the muscle taking on adult characteristics. Beginning at 16 days in utero and extending into the neonatal period, there was evidence of myotube death in the soleus muscle. 相似文献
106.
107.
Unusual trend in the prevalence of trisomy 13 in mothers aged 35 and older: A population based study of national congenital anomaly data 下载免费PDF全文
108.
Recent collections and the type specimen of Marasmiellus juniperinus, the type species of the genus, were examined. Phylogenetic placement, based on ribosomal large subunit (LSU) and internally transcribed spacer (ITS) sequences, is within the lentinuloid clade, nested among Gymnopus taxa. This placement dictates genus name usage and phylogenetic position of other putative species of Marasmiellus. The mating system is tetrapolar. 相似文献
109.
Julie A. Hawkins Laura White Olascoaga Colin E. Hughes José-Luis R. Contreras Jiménez Pedro Mercado Ruaro 《Plant Systematics and Evolution》1999,216(1-2):49-68
Morphometric, cytogenetic, geographical and ecological evidence for hybridization betweenParkinsonia aculeata andCercidium praecox is presented. Morphometric investigation using the character count procedure and cytogenetic observations confirm hybrid status. All diagnostic morphometric characters were intermediate in the hybrid. Both parents (2n = 28) show regular tetrad formation and pollen fertility greater than 94%. Hybrids have a chromosome number of 2n = 28 or 2n = 30, and display meiotic abnormalities including lagging chromosomes and micronucleus formation; less than 21% of hybrid pollen was fertile. Ecological and geographical information suggests that hybridization is occurring at increasing frequency due to the expanding range ofP. aculeata associated with cultivation as an ornamental, coupled with ecological disturbance and weediness, and the cultivation ofC. praecox and hybrids as fodder, ornamental and shade trees. Hybrid fertility and phenological observations, in conjunction with F-weighted principal component analysis, suggest that the progeny of F1 hybrids are established. The hybrid is formally described asP. ×carterae. 相似文献
110.