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排序方式: 共有1932条查询结果,搜索用时 171 毫秒
81.
Beth A. Derfus John W. Rachow Neil S. Mandel Adele L. Boskey Michael Buday Vladimir M. Kushnaryov Lawrence M. Ryan 《Arthritis \u0026amp; Rheumatology》1992,35(2):231-240
Objective. To identify the morphology of a mineral-forming fraction of adult porcine hyaline articular cartilage digest and characterize the mineral it forms. Methods. Electron microscopy, Fourier transform infrared (FTIR) spectroscopy, x-ray microanalysis, compensated polarized light microscopy, and biochemical studies including 14C-labeled UDPG pyrophosphohydrolase radiometric assay. Results. This fraction of articular cartilage digest contained membrane-limited vesicles resembling growth plate cartilage matrix vesicles and formed mineral after only 24 hours in physiologic salt solution containing 1 mM ATP. The mineral contained inorganic pyrophosphate, 95% of which derived from ATP, and phosphate, 93% of which derived from inorganic phosphate in the medium. The FTIR spectrum of this mineral closely resembled the spectrum of standard calcium pyrophosphate dihydrate (CPPD) crystals. Compensated polarized light microscopy showed positively birefringent, rod-shaped crystals morphologically identical to CPPD. Ca:P ratios, defined by energy-dispersive microanalysis, were also consistent with CPPD. Conclusion. The articular cartilage vesicle fraction of porcine hyaline cartilage is capable of generating mineral that strongly resembles CPPD. 相似文献
82.
Anna Haywood Helene Dreau Adele Timbs Anna Schuh John Old Shirley Henderson 《Annals of hematology》2010,89(12):1215-1221
Non-deletional α+-thalassaemia is associated with a higher degree of morbidity and mortality than deletional forms of α+-thalassaemia. Screening for the common deletional forms of α-thalassaemia by Gap-PCR is widely practiced; however, the detection
of non-deletional α-thalassaemia mutations is technically more labour-intensive and expensive, as it requires DNA sequencing.
In addition, the presence of four very closely homologous alpha globin genes and the frequent co-existence of deletional forms
of α-thalassaemia present another layer of complexity in the detection of these mutations. With growing evidence that non-deletional
α-thalassaemia is relatively common in the UK, there is a demand for technologies which can quickly and accurately screen
for these mutations. We describe a method utilising pyrosequencing for detecting the ten most common clinically significant
non-deletional α-thalassaemia mutations in the UK. We tested 105 patients with non-deletional α-thalassaemia and found 100%
concordance with known genotype as identified by Sanger sequencing. We found pyrosequencing to be simpler, more robust, quicker,
and cheaper than conventional sequencing, making it a good choice for rapid and cost-effective diagnosis of patients with
suspected non-deletional α-thalassaemia. The technique is also likely to help expedite prenatal diagnosis of pregnancies at
risk of α-thalassaemia major. 相似文献
83.
Tanya M Bardakjian Adele S Schneider David Ng Jennifer J Johnston Leslie G Biesecker 《BMC medical genetics》2009,10(1):137-7
Background
Anophthalmia and microphthalmia are etiologically and clinically heterogeneous. Lenz microphthalmia is a syndromic form that is typically inherited in an X-linked pattern, though the causative gene mutation is unknown. Townes-Brocks syndrome manifests thumb anomalies, imperforate anus, and ear anomalies. We present a 13-year-old boy with a syndromic microphthalmia phenotype and a clinical diagnosis of Lenz microphthalmia syndrome. 相似文献84.
K‐John J. Cheung Allen Delaney Susana Ben‐Neriah Jacquie Schein Tang Lee Sohrab P. Shah Dorothy Cheung Nathalie A. Johnson Andrew J. Mungall Adele Telenius Betty Lai Merrill Boyle Joseph M. Connors Randy D. Gascoyne Marco A. Marra Douglas E. Horsman 《Genes, chromosomes & cancer》2010,49(8):669-681
A multiplatform approach, including conventional cytogenetic techniques, BAC array comparative genomic hybridization, and Affymetrix 500K SNP arrays, was applied to the study of the tumor genomes of 25 follicular lymphoma biopsy samples with paired normal DNA samples to characterize balanced translocations, copy number imbalances, and copy‐neutral loss of heterozygosity (cnLOH). In addition to the t(14;18), eight unique balanced translocations were found. Commonly reported FL‐associated copy number regions were revealed including losses of 1p32‐36, 6q, and 10q, and gains of 1q, 6p, 7, 12, 18, and X. The most frequent regions affected by copy‐neutral loss of heterozygosity were 1p36.33 (28%), 6p21.3 (20%), 12q21.2‐q24.33 (16%), and 16p13.3 (24%). We also identified by SNP analysis, 45 aberrant regions that each affected one gene, including CDKN2A, CDKN2B, FHIT, KIT, PEX14, and PTPRD, which were associated with canonical pathways involved in tumor development. This study illustrates the power of using complementary high‐resolution platforms on paired tumor/normal specimens and computational analysis to provide potential insights into the significance of single‐gene somatic aberrations in FL tumorigenesis. © 2010 Wiley‐Liss,Inc. 相似文献
85.
Two‐dimensional knowledge‐based volumetric reconstruction of the right ventricle documents short‐term improvement in pulmonary hypertension
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86.
87.
Carlo Calabrese Annamaria Pisi Giulio Di Febo Giuseppina Liguori Gianfranco Filippini Maurizio Cervellera Valeria Righi Patrizia Lucchi Adele Mucci Luisa Schenetti Valeria Tonini Maria Raffaella Tosi Vitaliano Tugnoli 《Cancer epidemiology, biomarkers & prevention》2008,17(6):1386-1395
BACKGROUND AND AIMS: The metabolic profile and morphologic aspects of normal and pathologic human gastric mucosa were studied. The aim of the present research was the application of ex vivo high-resolution magic angle spinning magnetic resonance spectroscopy (HR-MAS MRS) to the human gastric tissue to get information on the molecular steps involved in gastric carcinogenesis and the identification of biochemical markers useful for the development of in vivo MRS methodologies to diagnose gastric pathologies in clinical situations. METHODS: Twelve normal subjects, five with autoimmune atrophic gastritis, five with Helicobacter pylori infection, and five with adenocarcinoma were examined. Ten biopsies were taken during endoscopy from each patient. Specimens from carcinoma were also obtained during gastrectomy. Of the 10 biopsies, 4 were used for histologic evaluation, 4 were fixed in glutaraldehyde and processed for transmission and scanning electron microscopy, and 2 were immersed in liquid nitrogen and stored at -85 degrees C for monodimensional and bidimensional ex vivo HR-MAS MRS analysis. RESULTS: Ex vivo HR-MAS MRS identified glycine, alanine, free choline, and triglycerides as possible molecular markers related to the human gastric mucosa differentiation toward preneoplastic and neoplastic conditions. Ultrastructural studies of autoimmune atrophic gastritis and gastric adenocarcinoma revealed lipid accumulations intracellularly and extracellularly associated with a severe prenecrotic hypoxia and mitochondria degeneration. CONCLUSIONS: This is the first report of synergic applications of ex vivo HR-MAS MRS and electron microscopy in studying the human gastric mucosa differentiation. This research provides useful information about some molecular steps involved in gastric carcinogenesis. The biochemical data obtained on gastric pathologic tissue could represent the basis for clinical applications of in vivo MRS. 相似文献
88.
Zoya R Yurkovetsky John M Kirkwood Howard D Edington Adele M Marrangoni Lyudmila Velikokhatnaya Matthew T Winans Elieser Gorelik Anna E Lokshin 《Clinical cancer research》2007,13(8):2422-2428
PURPOSE: Interferon (IFN)-alpha2b is the only Food and Drug Administration-approved treatment for operable high-risk melanoma that has been shown to significantly and durably prolong relapse-free survival (RFS) of patients with stage IIB-III melanoma. Development of reliable serum assays may contribute to the development of methods for earlier detection of melanoma and the selection of patients who may be most susceptible to current available interventions with IFNalpha. EXPERIMENTAL DESIGN: A powerful high-throughput xMAP multiplex immunobead assay technology (Luminex Corp., Austin, TX) was used to simultaneously test 29 cytokines, chemokines, angiogenic as well as growth factors, and soluble receptors in the sera of 179 patients with high-risk melanoma and 378 healthy individuals. RESULTS: Serum concentrations of interleukin (IL)-1alpha, IL-1beta, IL-6, IL-8, IL-12p40, IL-13, granulocyte colony-stimulating factor, monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, IFNalpha, tumor necrosis factor (TNF)-alpha, epidermal growth factor, vascular endothelial growth factor (VEGF), and TNF receptor II were found to be significantly higher in patients with resected high-risk melanoma compared with healthy controls. Bayesian Network algorithm classification of the data offered 90% sensitivity at 98% specificity with 96.5% of melanoma patients distinguished from healthy individuals. IFN-alpha2b therapy resulted in a significant decrease of serum levels of immunosuppressive and tumor angiogenic/growth stimulatory factors (VEGF, epidermal growth factor, and hepatocyte growth factor) and increased levels of antiangiogenic IFN-gamma inducible protein 10 (IP-10) and IFN-alpha. Pretreatment levels of proinflammatory cytokines IL-1beta, IL-1alpha, IL-6, TNF-alpha, and chemokines MIP-1alpha and MIP-1beta were found to be significantly higher in the serum of patients with longer RFS values of 1 to 5 and >5 years when compared with patients with shorter RFS of <1 year. CONCLUSION: These data show that multiplexed analysis of serum biomarkers is useful for the evaluation of prognostic markers of clinical outcome and potential predictive markers of response to IFN-alpha2b in patients with high-risk operable melanoma. 相似文献
89.
90.
Vanadyl as a catalyst of human lipoprotein oxidation 总被引:2,自引:0,他引:2
Lapenna D Ciofani G Bruno C Pierdomenico SD Giuliani L Giamberardino MA Cuccurullo F 《Biochemical pharmacology》2002,63(3):375-380
Lipoprotein oxidation, which is relevant to atherogenesis, can be induced by redox-active transition metals, such as copper. Vanadium is a metal usually used as vanadyl to improve metabolic control in diabetic patients; given its redox-active properties, we have investigated possible oxidative effects of the metal on lipoproteins from healthy and diabetic subjects. Beginning from 10 microM, vanadyl, but not vanadate, induced oxidation of the non-HDL fraction, which was inhibited by EDTA, butylated hydroxytoluene and Vitamins E and C, but not by mannitol, SOD and catalase. Differently from copper, vanadyl could oxidize directly lipoprotein lipids, although it showed a lower oxidant activity against critical tryptophan residues of the lipoprotein protein moiety. Moreover, the non-HDL fraction of diabetic patients was more susceptible to vanadyl-dependent oxidation than that of controls. Thus, vanadium, in its reduced form which may be used in humans, can oxidize the non-HDL fraction through oxidative effects exerted especially on lipoprotein lipids; the specific pro-oxidant activity of vanadyl is more evident with lipoproteins of diabetic patients. Given also the tissue accumulating capacity of vanadium conceivably in a reduced form, its prolonged administration to humans, especially to diabetic patients without adequate antioxidant supplementation, needs caution. 相似文献