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51.
Henri CM Heuven Rik HJ van Wijk Bert Dibbits Tony A van Kampen Egbert F Knol Henk Bovenhuis 《遗传、选种与进化》2009,41(1):4
Quantitative trait loci (QTL) affecting carcass and meat quality located on SSC2 were identified using variance component methods. A large number of traits involved in meat and carcass quality was detected in a commercial crossbred population: 1855 pigs sired by 17 boars from a synthetic line, which where homozygous (A/A) for IGF2. Using combined linkage and linkage disequilibrium mapping (LDLA), several QTL significantly affecting loin muscle mass, ham weight and ham muscles (outer ham and knuckle ham) and meat quality traits, such as Minolta-L* and -b*, ultimate pH and Japanese colour score were detected. These results agreed well with previous QTL-studies involving SSC2. Since our study is carried out on crossbreds, different QTL may be segregating in the parental lines. To address this question, we compared models with a single QTL-variance component with models allowing for separate sire and dam QTL-variance components. The same QTL were identified using a single QTL variance component model compared to a model allowing for separate variances with minor differences with respect to QTL location. However, the variance component method made it possible to detect QTL segregating in the paternal line (e.g. HAMB), the maternal lines (e.g. Ham) or in both (e.g. pHu). Combining association and linkage information among haplotypes improved slightly the significance of the QTL compared to an analysis using linkage information only. 相似文献
52.
Aulus EAD Barbosa Érika VS Albuquerque Maria CM Silva Djair SL Souza Osmundo B Oliveira-Neto Arnubio Valencia Thales L Rocha Maria F Grossi-de-Sa 《BMC biotechnology》2010,10(1):44
Background
Coffee is an important crop and is crucial to the economy of many developing countries, generating around US70 billion per year. There are 115 species in the < i > Coffea < /i > genus, but only two, < i > C. arabica < /i > and < i > C. canephora < /i > , are commercially cultivated. Coffee plants are attacked by many pathogens and insect-pests, which affect not only the production of coffee but also its grain quality, reducing the commercial value of the product. The main insect-pest, the coffee berry borer ( < i > Hypotheneumus hampei < /i > ), is responsible for worldwide annual losses of around US70 billion per year. There are 115 species in the Coffea genus, but only two, C. arabica and C. canephora, are commercially cultivated. Coffee plants are attacked by many pathogens and insect-pests, which affect not only the production of coffee but also its grain quality, reducing the commercial value of the product. The main insect-pest, the coffee berry borer (Hypotheneumus hampei), is responsible for worldwide annual losses of around US500 million. The coffee berry borer exclusively damages the coffee berries, and it is mainly controlled by organochlorine insecticides that are both toxic and carcinogenic. Unfortunately, natural resistance in the genus Coffea to H. hampei has not been documented. To overcome these problems, biotechnological strategies can be used to introduce an α-amylase inhibitor gene (α-AI1), which confers resistance against the coffee berry borer insect-pest, into C. arabica plants. 相似文献53.
54.
Oxidative stress contributes to cancer pathologies and to apoptosis. Marine algae exhibit cytotoxic, antiproliferative and apoptotic effects; their metabolites have been used to treat many types of cancer. We investigated in culture extracts of Petalonia fascia, Jania longifurca and Halimeda tuna to determine their effects on mouse neuroblastoma cell line, NA2B. NA2B cells were treated with algae extracts, and the survival and proliferation of NA2B cells were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The effects of algae extracts on oxidative stress in NA2B cells also were investigated using nitric oxide synthase (NOS) immunocytochemistry and apoptosis was assessed using terminal deoxynucleotidyl transferase dUTP nick end labeling. We observed significant neurite inhibition with moderate damage by the neurotoxicity-screening test (NST) at IC50 dilutions of the extracts. MTT demonstrated that J. longifurca extracts were more toxic than P. fascia and H. tuna extracts. We found an increase of endothelial and inducible NOS immunostaining for oxidative stress and TUNEL analysis revealed increased apoptosis after application of extract. Our findings suggest that the algae we tested may have potential use for treatment of cancer. 相似文献
55.
56.
CM Galmarini A Kertesz R Oliva J Porta F C Galmarini 《Cancer immunology, immunotherapy : CII》1998,15(4):282-285
Bone metastasis in the hand is rare. The etiology is quite different from that of metastasis to other bones; bronchogenic
carcinoma is by far the most frequent case. Distal phalanges are mainly involved with irregular osteolysis and cortical destruction.
Differential diagnosis of phalangeal metastasis includes osteomyelitis, rheumatoid arthritis and gout. The prognosis is always
that of metastatic bronchial cancer with an average survival of three months. Treatment may involve distal digital amputation
or antalgic radiotherapy. A case of bronchogenic carcinoma with metastasis to the thumb is presented. The metastasis was located
in the distal phalanx of the left thumb. The primary tumor was located in the lung. Treatment consisted of amputation. The
overall survival was five months. 相似文献
57.
Xa21D encodes a receptor-like molecule with a leucine-rich repeat domain that determines race-specific recognition and is subject to adaptive evolution. 总被引:19,自引:0,他引:19 下载免费PDF全文
G L Wang D L Ruan W Y Song S Sideris L Chen L Y Pi S Zhang Z Zhang C Fauquet B S Gaut M C Whalen P C Ronald 《The Plant cell》1998,10(5):765-779
58.
A protocol for consistent, large-scale production of fertile transgenic rice plants 总被引:10,自引:0,他引:10
A protocol for consistent production of fertile transgenic rice plants was established utilizing microparticle bombardment
of embryogenic tissues (Oryza sativa L. japonica cv. Taipei 309). This system has been employed to produce several thousand independently transformed plant lines
carrying the hygromycin phosphotransferase (hph) gene and various genes of interest. The most efficient target tissue was highly embryogenic callus or suspension cell aggregates,
when they were given an osmotic pre- and post-transformation treatment of 0.6 m carbohydrate. By optimizing the age of the tissue at the time of gene transfer and applying an improved selection procedure,
transgenic plants were recovered in 8 weeks from the time of gene transfer, at an average of 22.3±9.7 per 100 calli and 22.4±8.0
plant lines per dish of suspension cell aggregates. This system has facilitated a number of studies using rice as a model
for genetic transformation and will enable the large-scale production of transgenic rice plants for genomic studies.
Received: 12 March 1998 / Revision received: 5 May 1998 / Accepted: 15 May 1998 相似文献
59.
Prospects for estimating nucleotide divergence with RAPDs 总被引:11,自引:0,他引:11
The technique of random amplification of polymorphic DNA (RAPD), which is
simply polymerase chain reaction (PCR) amplification of genomic DNA by a
single short oligonucleotide primer, produces complex patterns of anonymous
polymorphic DNA fragments. The information provided by these banding
patterns has proved to be of great utility for mapping and for verification
of identity of bacterial strains. Here we consider whether the degree of
similarity of the banding patterns can be used to estimate nucleotide
diversity and nucleotide divergence. With haploid data, fragments generated
by RAPD-PCR can be treated in a fashion very similar to that for
restriction-fragment data. Amplification of diploid samples, on the other
hand, requires consideration of the fact that presence of a band is
dominant to absence of the band. After describing a method for estimating
nucleotide divergence on the basis of diploid samples, we summarize the
restrictions and criteria that must be met when RAPD data are used for
estimating population genetic parameters.
相似文献
60.
Protein slot blotting: An easy,rapid and reliable technique to identify the expression of a protein in transgenic plants 总被引:1,自引:1,他引:0
Alexandre de Kochko Rongda Qu Philippe Marmey Iann Rance Claude Fauquet Roger N. Beachy 《Plant Molecular Biology Reporter》1994,12(3):274-278
A technique based on immunological recognition of a foreign protein in transgenic plants has been developed. It allows a quick
and reliable screening of many plant samples, improves the accuracy of the results compared to ELISA and is easier to carry
out and more sensitive than a western immunoblot. This technique has also been tested to recognize foreign proteins in rice
and tobacco leaf extracts. 相似文献