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A chemically defined medium using commercially available alpha-MEM supplemented with hemin, HEPES, L-glutamine, D-glucose, folic acid, D-biotin and adenine supports the luxuriant growth and propagation of Leishmania donovani promastigotes. A peak parasite population of about 7.0 x 10(7)/ml at stationary phase and a population doubling time of 11.4 h for high-subpassage promastigotes were obtained. The medium was suitable for transformation of isolated amastigotes from infected hamster spleen. Promastigotes could be detected by culturing kala-azar patients' bone-marrow aspirate or spleen puncture material in this medium. Four out of six freshly transformed isolates gradually adapted and grew well in this medium. Macroscopic colonies appeared on agar plates prepared with the medium within 16-20 days after inoculation. The cloning efficiency was increased about five-fold by glycerol supplementation.  相似文献   
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A 2-month-old female with intrauterine and postnatal growth retardation, multiple congenital anomalies, absent right kidney, congenital heart disease was investigated. Her karyotype revealed, 46,XX,-10,+der(10), t(10;18) (p15;q12) pat. The child died at 2 months 2 weeks. This is the third case of trisomy 18q resulting from translocation of chromosome 10 and 18.  相似文献   
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Three genotypes of chickpea ICCV-1, ICCV-6 and a Desi (local) variety were tested for plant regeneration through multiple shoot production. The embryo axis was removed from mature seeds, the root meristem and the shoot apex were discarded. These explants were cultured on medium containing MS macro salts, 4X MS micro salts, I35 vitamins, 3.0 mg/1 BAP, 0.004 mg/1 NAA, 3% (w/v) sucrose and incubated at 260C. The explants were transformed withAgrobacterium tumefaciens strain LBA4404 with binary vector pBI121 containing theuidA andnptIl genes. Multiple shoots were repeatedly selected with kanamycin. The selected kanamycin resistant shoots were rooted on MS medium supplemented with 0.05 mg/1 113A. The presumptive transformants histochemically stained positive for GUS. Additionally, nptll assay confirmed the expression ofnptII in kanamycin resistant plants. Transgenic plants were transferred to soil and grown in the green house.Abbreviations BAP 6-benzylamino purine - 2,4-D 2,4dichlorophenoxy acetic acid - IAA Indole acetic acid - IBA Indole butaric acid - NAA Naphthalene acetic acid  相似文献   
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M. Kar  J. Feierabend 《Planta》1984,162(5):385-391
Pollen grains of Plumbago zeylanica L. were serially sectioned and examined using transmission electron microscopy to determine the three-dimensional organization of sperm cells within the microgametophyte and the quantity of membrane-bound organelles occurring within each cell. Sperm cells occur in pairs within each pollen grain, but are dimorphic, differing in size, morphology and organelle content. The larger of the two sperm cells (Svn) is distinguished by the presence of a long (approx. 30 m) projection, which wraps around and lies within embayments of the vegetative nucleus. This cell contains numerous mitochondria, up to two plastids and, infrequently, microbodies. It is characterized by a larger volume and surface area and contains a larger nucleus than the other sperm cell. The second sperm cell (Sua) is linked by plasmodesmata with the Svn, but is unassociated with the vegetative nucleus. It is smaller and lacks a cellular projection. The Sua contains relatively few mitochondria, but numerous (up to 46) plastids and more microbodies than the other sperm. The degree of dimorphism in their content of heritable cytoplasmic organelles must at fertilization result in nearly unidirectional transmission of sperm plastids into just one of the two female reproductive cells, and preferential transmission of sperm mitochondria into the other.Abbreviations Sua sperm cell unassociated with the vegetative nucleus - Svn sperm cell physically associated with the vegetative nucleus 1=Russell and Cass (1981)  相似文献   
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The inability of cells to maintain protein folding homeostasis is implicated in the development of neurodegenerative diseases, malignant transformation, and aging. We find that multiphoton fluorescence imaging of 1-anilinonaphthalene-8-sulfonate (ANS) can be used to assess cellular responses to protein misfolding stresses. ANS is relatively nontoxic and enters live cells and cells or tissues fixed in formalin. In an animal model of Alzheimer’s disease, ANS fluorescence imaging of brain tissue sections reveals the binding of ANS to fibrillar deposits of amyloid peptide (Aβ) in amyloid plaques and in cerebrovascular amyloid. ANS imaging also highlights non-amyloid deposits of glial fibrillary acidic protein in brain tumors. Cultured cells under normal growth conditions possess a number of ANS-binding structures. High levels of ANS fluorescence are associated with the endoplasmic reticulum (ER), Golgi, and lysosomes—regions of protein folding and degradation. Nuclei are virtually devoid of ANS binding sites. Additional ANS binding is triggered by hyperthermia, thermal lesioning, proteasome inhibition, and induction of ER stress. We also use multiphoton imaging of ANS binding to follow the in vivo recovery of cells from protein-damaging insults over time. We find that ANS fluorescence tracks with the binding of the molecular chaperone Hsp70 in compartments where Hsp70 is present. ANS highlights the sensitivity of specific cellular targets, including the nucleus and particularly the nucleolus, to thermal stress and proteasome inhibition. Multiphoton imaging of ANS binding should be a useful probe for monitoring protein misfolding stress in cells.  相似文献   
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