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排序方式: 共有227条查询结果,搜索用时 15 毫秒
71.
72.
Hernández Pérez A E Cerna Chávez JC Delgado Ortiz M Beltrán Beache LM Tapia Vargas YM Ochoa Fuentes 《Phyton》2019,88(1):11-13
Mexico is the main producer, consumer and exporter
of avocado in the world, being Michoacan the main producer state
contributing more than 80% of the national production. There
are phytopathogens that decimate the production causing the
death of the tree. Root samples were collected in avocado trees
that showed the characteristic symptomatology of the disease
known as avocado sadness, the sampling was carried out in four
of the main avocado producing towns, in the state of Michoacan,
Mexico. The isolation consisted in sowing root tissue in Petri
dishes with V8®-PARPH culture medium, subsequently they were
identified morphologically and for species level it was determined
by molecular biology, with the PCR-ITS technique. Pathogenicity
tests were performed in triplicate with avocado seedlings with more
than six leaves. After 24 hours, the inoculated plants expressed
decay in the apical part, after 120 hours the leaves showed yellowing
and after 15 days there was a generalized wilt on the stem and
leaves, re-isolating the phytopathogen Phytopythium vexans.
This study confirms the first report of the oomycete P. vexans
affecting avocado trees in the most important producing region of
the Mexican Republic. 相似文献
73.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
74.
75.
76.
Mehrara BJ Santoro TD Arcilla E Watson JP Shaw WW Da Lio AL 《Plastic and reconstructive surgery》2006,118(5):1100-9; discussion 1110-1
77.
Regulation of cellular adhesion molecule expression in murine oocytes, peri-implant ation and post-implantation embryos 总被引:2,自引:0,他引:2
DAVID P LU LINA TIAN CHRIS O'''' NEILL NICHOLAS JC KING Department of Pathology University of Sydney NSW AustraliaHuman Reproduction Unit Department of Physiology University of Sydney Royal North Shore Hospital NSW Australia 《Cell research》2002,(Z2)
Expression of the adhesion molecules, ICAM-1, VCAM-1, NCAM, CD44, CD49d (VLA-4, a chain), and CDlla (LFA-1, a chain) on mouse oocytes, and pre- and peri-implantation stage embryos was examined by quantitative indirect immunofluorescence microscopy. ICAM-1 was most strongly expressed at the oocyte stage, gradually declining almost to undetectable levels by the expanded blastocyst stage. NCAM, also expressed maximally on the oocyte, declined to undetectable levels beyond the morula stage. On the other hand, CD44 declined from highest expression at the oocyte stage to show a second maximum at the compacted 8-cell/morula. This molecule exhibited high expression around contact areas between trophecto-derm and zona pellucida during blastocyst hatching. CD49d was highly expressed in the oocyte, remained significantly expressed throughout and after blastocyst hatching was expressed on the polar trophecto-derm. Like CD44, CD49d declined to undetectable levels at the blastocyst outgrowth stage. Expression of both 相似文献
78.
Yung-Shyeng Tsao Russell Condon Eugene Schaefer Peggy Lio Zhong Liu 《Cytotechnology》2001,37(3):189-198
Human Embryonic Kidney 293 (HEK293) cells were adapted into a serum-free suspension medium through steps of gradual serum
weaning for the production of adenoviral (AdV) gene therapy vectors. The presence of sodium heparin in the medium formulation
reduced cell clumping dramatically in suspension culture. The adapted cells were ready to grow either in serum-containing
medium as an attached culture or in serum-free medium in suspension culture. A scalable production process was developed in
shake flasks and was then evaluated in stirred tank bioreactors. This process includes a growth phase in batch-mode followed
by a production phase involving medium perfusion and supplementation. Fortification with calcium chloride post viral inoculation
resulted in an increase in virus production by at least one fold. Addition of stimulating agents such as sodium butyrate,
N-acetyl-L-cysteine (NAC), dimethyl sulfoxide(DMSO), or ethyl alcohol post infection was shown to further improve virus production
in a dose-dependent manner. The serum-free suspension process described here should be suitable for the manufacturing of other
E1-deleted AdV vectors and could potentially be used for the production of recombinant proteins by HEK293 cells.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
79.
80.
Microsatellite allele frequencies in humans and chimpanzees, with implications for constraints on allele size 总被引:24,自引:6,他引:18
The distributions of allele sizes at eight simple-sequence repeat (SSR) or
microsatellite loci in chimpanzees are found and compared with the
distributions previously obtained from several human populations. At
several loci, the differences in average allele size between chimpanzees
and humans are sufficiently small that there might be a constraint on the
evolution of average allele size. Furthermore, a model that allows for a
bias in the mutation process shows that for some loci a weak bias can
account for the observations. Several alleles at one of the loci (Mfd 59)
were sequenced. Differences between alleles of different lengths were found
to be more complex than previously assumed. An 8-base-pair deletion was
present in the nonvariable region of the chimpanzee locus. This locus
contains a previously unrecognized repeated region, which is imperfect in
humans and perfect in chimpanzees. The apparently greater opportunity for
mutation conferred by the two perfect repeat regions in chimpanzees is
reflected in the higher variance in repeat number at Mfd 59 in chimpanzees
than in humans. These data indicate that interspecific differences in
allele length are not always attributable to simple changes in the number
of repeats.
相似文献