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The history of chemical investigations into the yellow components of turmeric can be traced from 1815. Although the major yellow component of turmeric, curcumin, often is represented as a 1,3-diketone in the solid state and in nonaqueous solution, it exists in the enol form. The struggle to identify the chemical structure of curcumin continued for nearly a century and was complicated by the difficult purification of curcumin and by the presence of two additional yellow components. Food remains the main use for turmeric (old spice); its use as a dye has diminished since the 19th century, but it may have pharmaceutical uses (new spice).  相似文献   
83.
A cDNA clone encoding the major antigen (CDR62) associated with the antibody-induced paraneoplastic cerebellar degeneration has been used to identify the chromosomal location of the corresponding structural gene(s) by screening for its retention in a panel of rodent-human somatic cell hybrids. Having established the synteny of the gene with the autosome 16, we proceeded to its precise subregional mapping by in situ fluorescence hybridization with a recombinant lambda phage containing the genomic region homologous to the cDNA gene. The latter studies pin-pointed the chromosomal localization of the structural CDR62 gene within the interval 16p12-16p13.1.  相似文献   
84.

Background

Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.

Methods

The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.

Results

For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.

Conclusion

In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.  相似文献   
85.
Anni 2.0 is an online tool () to aid the biomedical researcher with a broad range of information needs. Anni provides an ontology-based interface to MEDLINE and retrieves documents and associations for several classes of biomedical concepts, including genes, drugs and diseases, with established text-mining technology. In this article we illustrate Anni's usability by applying the tool to two use cases: interpretation of a set of differentially expressed genes, and literature-based knowledge discovery.  相似文献   
86.
The results of a serological survey of livestock in Kazakhstan, carried out in 1997–1998, are reported. Serum samples from 958 animals (cattle, sheep and goats) were tested for antibodies to foot and mouth disease (FMD), bluetongue (BT), epizootic haemorrhagic disease (EHD), rinderpest (RP) and peste des petits ruminants (PPR) viruses, and to Brucella spp. We also investigated the vaccination status of livestock and related this to changes in veterinary provision since independence in 1991. For the 2 diseases under official surveillance (FMD and brucellosis) our results were similar to official data, although we found significantly higher brucellosis levels in 2 districts and widespread ignorance about FMD vaccination status. The seroprevalence for BT virus was 23%, and seropositive animals were widespread suggesting endemicity, despite the disease not having being previously reported. We found a few seropositives for EHDV and PPRV, which may suggest that these diseases are also present in Kazakhstan. An hierarchical model showed that seroprevalence to FMD and BT viruses were clustered at the farm/village level, rather than at a larger spatial scale. This was unexpected for FMD, which is subject to vaccination policies which vary at the raion (county) level.  相似文献   
87.
Focal adhesion kinase (FAK) is activated following integrin engagement or stimulation of transmembrane receptors. Autophosphorylation of FAK on Tyr-397 is a critical event, allowing binding of Src family kinases and activation of signal transduction pathways. Tissue-specific alternative splicing generates several isoforms of FAK with different autophosphorylation rates. Despite its importance, the mechanisms of FAK autophosphorylation and the basis for differences between isoforms are not known. We addressed these questions using isoforms of FAK expressed in brain. Autophosphorylation of FAK(+), which is identical to that of "standard" FAK, was intermolecular in transfected cells, although it did not involve the formation of stable multimeric complexes. Coumermycin-induced dimerization of gyrase B-FAK(+) chimeras triggered autophosphorylation of Tyr-397. This was independent of cell adhesion but required the C terminus of the protein. In contrast, the elevated autophosphorylation of FAK(+6,7), the major neuronal splice isoform, was not accounted for by transphosphorylation. Specifically designed immune precipitate kinase assays confirmed that autophosphorylation of FAK(+) was intermolecular, whereas autophosphorylation of FAK(+6,7) or FAK(+7) was predominantly intramolecular and insensitive to the inhibitory effects of the N-terminal domain. Our results clarify the mechanisms of FAK activation and show how alternative splicing can dramatically alter the mechanism of autophosphorylation of a protein kinase.  相似文献   
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Growth plate compressions and altered hematopoiesis in collagen X null mice   总被引:5,自引:0,他引:5  
A variable skeleto-hematopoietic phenotype was observed in collagen X null mice which mirrored the defects in transgenic (Tg) mice with dominant interference collagen X mutations (Jacenko, O., P. LuValle, and B.R. Olsen. 1993. Nature. 365:56-61). Specifically, perinatal lethality was seen in approximately 10.8% of null mutants at week three after birth, and in another subset by 12 wk. In perinatal lethal mutants, growth plates were compressed, trabecular bone reduced, and hematopoietic aplasia and erythrocyte-filled vascular sinusoids were apparent in marrows. Lymphatic organs, reduced to approximately 80% that of controls, displayed altered architecture and lymphocyte content. In thymuses, a paucity of cortical CD3(+)/CD4(+)/CD8(+) lymphocytes was consistent with the marrow's inability to replenish maturing T cells. In spleens, an unaltered T cell distribution was coupled with diffuse staining for IgD(+)/B220(+) B cells, whose reduction was prominent in poorly organized lymphatic nodules. Disorderly arrays of splenic macrophages surrounding periarteriolar lymphatic sheaths and a red pulp depletion further complemented the Tg perinatal lethal phenotype. Moreover, subtle growth plate compressions and hematopoietic changes were seen in all null mice. Data from Tg and null mice implicate the disruption of collagen X function in the observed skeleto-hematopoietic defects, and suggest that hypertrophic cartilage and endochondral skeletogenesis may contribute to the marrow microenvironment prerequisite for blood cell differentiation.  相似文献   
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