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排序方式: 共有1376条查询结果,搜索用时 15 毫秒
31.
Coakley G; Mok CC; Hajeer AH; Ollier WE; Turner D; Sinnott PJ; Hutchinson IV; Panayi GS; Lanchbury JS 《Rheumatology (Oxford, England)》1998,37(9):988-991
OBJECTIVE: To examine whether promoter polymorphisms associated with
variation in interleukin-10 (IL-10) production are relevant to the
development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS:
DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The
promoter region between -533 and - 1120 was amplified by polymerase chain
reaction, and polymorphisms detected by restriction enzyme digest or
sequence-specific oligonucleotide probing. RESULTS: We found no significant
difference in allele or haplotype frequencies between the groups.
CONCLUSION: There is no association between FS or RA and these recently
identified IL-10 promoter polymorphisms. Other genetic or environmental
factors could explain the alterations in IL-10 levels seen in these
conditions.
相似文献
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D C DeVivo M W Haymond M P Leckie Y L Bussman D B McDougal A S Pagliara 《The Journal of clinical endocrinology and metabolism》1977,45(6):1281-1296
A 10 month old female infant was evaluated for severe lactic acidosis. Clinically she was well nourished and had a substantial amount of adipose tissue despite recurrent episodes of acidosis. Her psychomotor development was retarded, her movements were dystonic and generalized seizures punctuated her course. Metabolic abnormalities included elevated blood concentrations of lactate, pyruvate, beta-hydroxybutyrate, acetoacetate, alanine, proline and glycine, decreased blood concentrations of glutamine, aspartate, valine and citrate, and intermittent elevations of serum cholesterol. A trial on a high-fat diet worsened the clinical condition and intensified the ketoacidosis and hyperalaninemia. Analysis of hepatic tissue obtained by open biopsy revealed increased concentrations of lactate, alanine, acetyl-CoA and other short-chain acyl-CoA esters, and decreased concentrations of oxaloacetate, citrate, alpha-ketoglutarate, malate and aspartate. The blood and tissue metabolic perturbations reflected a deficiency of hepatic pyruvate carboxylase. The apparent Km of hepatic citrate synthase for oxaloacetate was 4.6 micrometer. Calculated tissue oxaloacetate concentrations were 0.50--0.84 micrometer suggesting that tricarboxylic acid cycle activity was severely limited by the decreased availability of this substrate. An iv glucose tolerance test resulted in the paradoxical synthesis of ketone bodies. This observation, coupled with the intermittent hypercholesterolemia and the increased tissue acetyl-CoA concentrations, suggests that pyruvate carboxylase is important in modulating the fractional distribution of intracellular acetyl-CoA between the tricarboxylic acid cycle, the beta-hydroxy-beta-methyl-glutaryl-CoA cycle (and the synthesis of cholesterol and ketone bodies), and fatty acid synthesis. Treatment in future cases might be directed toward increasing tissue concentrations of oxaloacetate. 相似文献
33.
Marco Gerlinger Sergio A Quezada Karl S Peggs Andrew JS Furness Rosalie Fisher Teresa Marafioti Vishvesh H Shende Nicholas McGranahan Andrew J Rowan Steven Hazell David Hamm Harlan S Robins Lisa Pickering Martin Gore David L Nicol James Larkin Charles Swanton 《The Journal of pathology》2013,231(4):424-432
The recognition of cancer cells by T cells can impact upon prognosis and be exploited for immunotherapeutic approaches. This recognition depends on the specific interaction between antigens displayed on the surface of cancer cells and the T cell receptor (TCR), which is generated by somatic rearrangements of TCR α‐ and β‐chains (TCRb). Our aim was to assess whether ultra‐deep sequencing of the rearranged TCRb in DNA extracted from unfractionated clear cell renal cell carcinoma (ccRCC) samples can provide insights into the clonality and heterogeneity of intratumoural T cells in ccRCCs, a tumour type that can display extensive genetic intratumour heterogeneity (ITH). For this purpose, DNA was extracted from two to four tumour regions from each of four primary ccRCCs and was analysed by ultra‐deep TCR sequencing. In parallel, tumour infiltration by CD4, CD8 and Foxp3 regulatory T cells was evaluated by immunohistochemistry and correlated with TCR‐sequencing data. A polyclonal T cell repertoire with 367–16 289 (median 2394) unique TCRb sequences was identified per tumour region. The frequencies of the 100 most abundant T cell clones/tumour were poorly correlated between most regions (Pearson correlation coefficient, –0.218 to 0.465). 3–93% of these T cell clones were not detectable across all regions. Thus, the clonal composition of T cell populations can be heterogeneous across different regions of the same ccRCC. T cell ITH was higher in tumours pretreated with an mTOR inhibitor, which could suggest that therapy can influence adaptive tumour immunity. These data show that ultra‐deep TCR‐sequencing technology can be applied directly to DNA extracted from unfractionated tumour samples, allowing novel insights into the clonality of T cell populations in cancers. These were polyclonal and displayed ITH in ccRCC. TCRb sequencing may shed light on mechanisms of cancer immunity and the efficacy of immunotherapy approaches. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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The molecular circuitries controlling the process of skin wound healing have gained new significant insights in recent years. This knowledge is built on landmark studies on skin embryogenesis, maturation, and differentiation. Furthermore, the identification, characterization, and elucidation of the biological roles of adult skin epithelial stem cells and their influence in tissue homeostasis have provided the foundation for the overall understanding of the process of skin wound healing and tissue repair. Among numerous signaling pathways associated with epithelial functions, the PI3K/Akt/mTOR signaling route has gained substantial attention with the generation of animal models capable of dissecting individual components of the pathway, thereby providing a novel insight into the molecular framework underlying skin homeostasis and tissue regeneration. In this review, we focus on recent findings regarding the mechanisms involved in wound healing associated with the upregulation of the activity of the PI3K/Akt/mTOR circuitry. This review highlights critical findings on the molecular mechanisms controlling the activation of mTOR, a downstream component of the PI3K–PTEN pathway, which is directly involved in epithelial migration and proliferation. We discuss how this emerging information can be exploited for the development of novel pharmacological intervention strategies to accelerate the healing of critical size wounds. 相似文献
37.
Boris Gershman Anthony L. Zietman Adam S. Feldman W. Scott McDougal 《Urologic oncology》2013,31(7):1093-1097
ObjectiveTo evaluate the use of transperineal template-guided prostate biopsy for patients with persistently elevated PSA despite multiple negative prior biopsies.Materials and methodsA retrospective review was performed of patients with at least two prior prostate biopsies who underwent transperineal template-guided biopsy. Electronic medical records were reviewed to obtain relevant clinical, laboratory, and pathologic data.ResultsA total of 34 patients underwent transperineal template-guided biopsy. Patients had a mean of 3.7 ± 1.6 (range 2–8) prior biopsies, including prior negative transurethral resection (TUR) biopsy in 6 (17.6%) patients. Prostate cancer was detected in 17 (50%) of the 34 patients. Of these, 14 (82.4%) patients had cancer in the anterior prostate, 9 (52.9%) patients had cancer in the apical prostate, and 16 (94.1%) patients had cancer in either the anterior or apical prostate. Gleason score was 3+3 in 9 (52.9%) patients and 3+4 or greater in 7 (47.1%) patients. The mean number of positive cores was 4.5 ± 3.0 (range 1–11). Of the 17 patients with a diagnosis of cancer, 7 underwent radical prostatectomy, 7 underwent radiation therapy, 1 elected active surveillance, and 1 was deciding between surgery and radiation therapy; 1 patient received palliative chemotherapy for synchronous metastatic pancreatic carcinoma. Patients in whom cancer was detected had significantly smaller prostate volume, higher PSA, higher PSA density, and greater PSA velocity.ConclusionsTransperineal template-guided prostate biopsy is an effective technique for detecting cancer in patients with persistently elevated PSA despite multiple negative biopsies. It improves sampling of the anterior and apical prostate, and should be included as part of the diagnostic algorithm to reduce extensive repeat biopsy. 相似文献
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