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71.
Mathilde W. N. Yu Suzanne Lemieux Pierre J. Talbot 《European journal of immunology》1996,26(12):3230-3233
The idiotypic network can be experimentally altered to induce protective immune responses against microbial pathogens. Both internal image and noninternal image anti-idiotypic (anti-Id) antibodies have been shown to trigger antigen (Ag)-specific immune responses. Therefore, mechanisms of anti-Id vaccination appear to go beyond structural mimicry of Ag, but remain undefined. Using the neurotropic murine coronavirus animal model, we have previously shown that a polyclonal noninternal image anti-Id (Ab2) could vaccinate BALB/c mice. To characterize its mode of action, we have examined the immune modulating capability of this Ab2 in vivo in strains of mice with different H-2 haplotypes. Even though only internal image anti-Id are expected to induce non-genetically restricted immunity, this noninternal image Ab2 induced protective immunity in four of eight genetically different strains of mice susceptible to coronavirus infection. These were BALB/c (H-2d), DBA/1 (H-2d), DBA/1 (H-2q), and SWR (H-2q) mice. Protection was generally correlated with the induction of specific antiviral Ab (Ab3) that showed biological properties, such as virus neutralization in vitro, similar to the initial Ab1. To evaluate the genetic implication of the H-2 haplotypes in protection, congenic mice were also tested. Vaccination profiles suggest that cooperation between background gene(s) of the BALB/c mouse with H-2d and H-2q loci is necessary for an optimal protective immune response, although the main genetic element(s) regulating the antiviral response to Ab2 inoculation appeared to be located outside the major histocompatibility complex. These results are consistent with the ability of Ab2 to induce protective antiviral antibodies in genetically different animals by biological mimicry. 相似文献
72.
Summary Electron microscopy of toad (Bufo marinus) muscle fixed without relaxing after a single eccentric contraction at muscle lengths greater than optimum showed over-stretched half-sarcomeres in sufficient numbers to account for more than half of the imposed stretch. Such sarcomeres were absent in another muscle fixed without relaxing after an isometric contraction at the same length and largely absent in a third muscle that underwent eccentric contraction at muscle lengths less than optimum. This provides direct evidence in support of the hypothesis that lengthening of muscles at long length involves lengthening of a few half sarcomeres to beyond filament overlap, while most half sarcomeres are extended much less than in proportion to muscle extension. 相似文献
73.
A genetic linkage map for zebrafish: comparative analysis and localization of genes and expressed sequences 下载免费PDF全文
Gates MA Kim L Egan ES Cardozo T Sirotkin HI Dougan ST Lashkari D Abagyan R Schier AF Talbot WS 《Genome research》1999,9(4):334-347
Genetic screens in zebrafish (Danio rerio) have isolated mutations in hundreds of genes with essential functions. To facilitate the identification of candidate genes for these mutations, we have genetically mapped 104 genes and expressed sequence tags by scoring single-strand conformational polymorphisms in a panel of haploid siblings. To integrate this map with existing genetic maps, we also scored 275 previously mapped genes, microsatellites, and sequence-tagged sites in the same haploid panel. Systematic phylogenetic analysis defined likely mammalian orthologs of mapped zebrafish genes, and comparison of map positions in zebrafish and mammals identified significant conservation of synteny. This comparative analysis also identified pairs of zebrafish genes that appear to be orthologous to single mammalian genes, suggesting that these genes arose in a genome duplication that occurred in the teleost lineage after the divergence of fish and mammal ancestors. This comparative map analysis will be useful in predicting the locations of zebrafish genes from mammalian gene maps and in understanding the evolution of the vertebrate genome. 相似文献
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75.
Edith U Ebeledike Godwin IC Nwokedi Okechukwu O Ndu Festus BC Okoye Izuchukwu S Ochiogu 《Asian Pacific journal of tropical medicine》2010,3(5):395-398
ObjectiveTo investigate the calcium and phosphorus contents of four domestic animals used as sources of meat in Nigeria.MethodsThe calcium contents of the body parts of the animals were determined using atomic absorption spectrometer. Their phosphorus contents were determined colorimetrically using the molybdenum blue method.ResultsThe calcium and phosphorus contents were significantly higher in the bone samples than in the other animal parts investigated (P<0.05). The calcium contents of all the edible parts were higher in chicken than in the other animals. High calcium and phosphorus contents were detected in the faeces of chicken and goat, and that of cattle and goat, respectively. Low calcium and phosphorus contents were detected in the urine samples. Calcium: phosphorus ratios calculated for the bones of chicken, cattle and goat were satisfactory.ConclusionsIn conclusion, calcium and phosphorus contents of the animal parts vary significantly and their relative contents may be related to the animal's diet. Chicken parts may be the preferred dietary source of these minerals. This study highlights the need for routine investigation of the mineral contents of food, which is necessary for proper nutritional guidelines. 相似文献
76.
Alexandra Dimitrakopoulou Ernest Schilders Quamar Bismil J. Charles Talbot Konstantinos Kazakos 《Knee surgery, sports traumatology, arthroscopy》2010,18(5):691-693
We present a case of a high-level rugby player with severe groin pain following a partial rupture of his left adductor longus enthesis during a game. Conservative treatment proved unsuccessful and the athlete had persistent symptoms, affecting his quality of life and ability to play sports. Further assessments revealed a large bony spur/enthesophyte at adductor longus origin. The patient underwent a successful surgical resection of the active bone formation. 相似文献
77.
H. Keipp B. Talbot James E. Crowe Jr. Kathryn M. Edwards Marie R. Griffin Yuwei Zhu Geoffrey A. Weinberg Peter G. Szilagyi Caroline B. Hall Amy B Podsiad Marika Iwane John V. Williams 《Journal of medical virology》2009,81(5):853-856
There is only limited knowledge on the burden of disease due to both new (HCoV‐NL63 and HKU‐1) and previously discovered coronaviruses (OC43 and 229E) in children. Respiratory specimens and clinical data were prospectively collected in an active, population‐based surveillance study over a 2‐year period from children aged <5 years hospitalized with acute respiratory symptoms or fever. These samples were retrospectively tested by real‐time RT‐PCR for HCoV‐NL63, HKU1, OC43, and 229E. Human coronaviruses (HCoVs) were identified in 2.2% of study children <2 years of age. Rates of HCoV‐associated hospitalization per 10,000 were 10.2 (95% CI 4.3, 17.6), 4.2 (95% CI 1.9, 6.9), and 0 (95% CI 0, 3.7) in children aged <6 months, 6–23 months, and 24–59 months, respectively. Coronaviruses were identified in a modest number of hospitalized children. J. Med. Virol. 81:853–856, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
78.
79.
The expression of E-cadherin and catenins in colorectal tumours from familial adenomatous polyposis patients 总被引:2,自引:0,他引:2
Familial adenomatous polyposis patients (FAP) harbour a germline mutation of the adenomatous polyposis coli gene (APC), and APC mutations are early events in the development of sporadic colorectal neoplasms. The APC protein interacts with beta-catenin and gamma-catenin and APC mutations are believed to play a role in the altered levels of beta-catenin in colorectal tumours. Immunohistochemical studies have shown changes in the expression and distribution of E-cadherin and catenins in sporadic colorectal neoplasms. This study assessed the expression and distribution of E-cadherin and catenins in colorectal neoplasms and non-neoplastic mucosa from FAP patients. The expression and cellular distribution of E-cadherin and catenins were studied by immunohistochemistry in 61 adenomas, five carcinomas, and non-neoplastic mucosa from 18 FAP patients. mRNA levels in the carcinomas were studied by in situ hybridization. The expression of E-cadherin and catenins was increased in over 80% of the adenomas, with evident cytoplasmic immunoreactivity. There was increased expression of E-cadherin and catenin in the carcinomas, with a notable increase in the levels of mRNA, in comparison with the non-neoplastic mucosa. 相似文献
80.
Pattanasak Mongkolwat Vladimir Kleper Skip Talbot Daniel Rubin 《Journal of digital imaging》2014,27(6):692-701
Knowledge contained within in vivo imaging annotated by human experts or computer programs is typically stored as unstructured text and separated from other associated information. The National Cancer Informatics Program (NCIP) Annotation and Image Markup (AIM) Foundation information model is an evolution of the National Institute of Health’s (NIH) National Cancer Institute’s (NCI) Cancer Bioinformatics Grid (caBIG®) AIM model. The model applies to various image types created by various techniques and disciplines. It has evolved in response to the feedback and changing demands from the imaging community at NCI. The foundation model serves as a base for other imaging disciplines that want to extend the type of information the model collects. The model captures physical entities and their characteristics, imaging observation entities and their characteristics, markups (two- and three-dimensional), AIM statements, calculations, image source, inferences, annotation role, task context or workflow, audit trail, AIM creator details, equipment used to create AIM instances, subject demographics, and adjudication observations. An AIM instance can be stored as a Digital Imaging and Communications in Medicine (DICOM) structured reporting (SR) object or Extensible Markup Language (XML) document for further processing and analysis. An AIM instance consists of one or more annotations and associated markups of a single finding along with other ancillary information in the AIM model. An annotation describes information about the meaning of pixel data in an image. A markup is a graphical drawing placed on the image that depicts a region of interest. This paper describes fundamental AIM concepts and how to use and extend AIM for various imaging disciplines. 相似文献