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排序方式: 共有213条查询结果,搜索用时 31 毫秒
1.
Fibronectin with IIICS region is present in rheumatoid synovium, and fibronectin fragments are increased in rheumatoid joints. We investigated the ability of COOH-terminal heparin-binding fibronectin fragment (COOH-HBFN-f) containing IIICS to induce matrix metalloproteinase (MMP) production and the role of mitogen-activated protein kinase (MAPK) pathway and CS-1 sequence that can bind alpha4beta1 integrin in MMP induction by COOH-HBFN-f in rheumatoid synovial fibroblasts (RSF). When RSF in monolayer culture were incubated with COOH-HBFN-f, COOH-HBFN-f stimulated the production of MMP-1, MMP-3, and MMP-13 by RSF in association with activation of extracellular signal-regulated kinase, p38 MAPK, and c-Jun NH(2)-terminal kinase. Immunoprecipitation of cell lysates demonstrated the presence of alpha4 integrin in cultured RSF. Similar to COOH-HBFN-f, treatment with CS-1 synthetic peptide derived from IIICS resulted in increased MMP production and activation of the kinases, although the MMP levels were low. Preincubation of RSF with anti-alpha4 integrin antibody resulted in partial suppression of the COOH-HBFN-f-stimulated MMP production. Inhibition studies using protein kinase inhibitors (PD98059 and SB203580) showed that those MAPK pathways contributed to MMP up-regulation by COOH-HBFN-f and CS-1. Thus, the present results have clearly shown that COOH-HBFN-f and CS-1 stimulate MMP production in association with activation of MAPK pathways in RSF. Integrin alpha4beta1 may be partially involved in the MMP induction by COOH-HBFN-f.  相似文献   
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National and international guidelines have been published recommending the use of natriuretic peptides as an aid to the diagnosis of heart failure (HF) in acute settings; however, few specific recommendations exist for governing the use of these peptides in primary care populations. To summarize the available data relevant to the diagnosis of HF in primary care patient population, we systematically reviewed the literature to identify original articles that investigated the diagnostic accuracy of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) in primary care settings. The search yielded 25,864 articles in total: 12 investigating BNP and 20 investigating NT-proBNP were relevant to our objective and included in the review. QUADAS-2 and GRADE were used to assess the quality of the included articles. Diagnostic data were pooled based on three cutpoints: lowest and optimal, as chosen by study authors, and manufacturers’ suggested. The effect of various determinants (e.g., age, gender, BMI, and renal function) on diagnostic performance was also investigated. Pooled sensitivity and specificity of BNP and NT-proBNP using the lowest [0.85 (sensitivity) and 0.54 (specificity)], optimal (0.80 and 0.61), and manufacturers’ (0.74 and 0.67) cutpoints showed good performance for diagnosing HF. Similar performance was seen for NT-proBNP: lowest (0.90 and 0.50), optimal (0.86 and 0.58), and manufacturers’ (0.82 and 0.58) cutpoints. Overall, we rated the strength of evidence as high because further studies will be unlikely to change the estimates diagnostic performance.  相似文献   
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The aim of this systematic review was to determine whether B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) independently add incremental value for predicting mortality and morbidity in patients with acute decompensated heart failure (ADHF). Medline®, Embase?, AMED, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL were searched from 1989 to June 2012. We also searched reference lists of included articles, systematic reviews, and the gray literature. Studies were screened for eligibility criteria and assessed for risk of bias. Data were extracted on study design, population demographics, assay cutpoints, prognostic risk prediction model covariates, statistical methods, outcomes, and results. From 183 citations, only seven studies (5 BNP and 2 NT-proBNP) considered incremental value in ADHF subjects admitted to acute care centers. Admission assay levels and length of follow-up varied for BNP studies (31 days to 12 months) and for NT-proBNP studies (25–82 months). All studies presented at least one estimate of incremental value of BNP/NT-proBNP relative to the base prognostic model. Using discrimination or likelihood statistics, these studies consistently showed that BNP or NT-proBNP increased model performance. Three studies used reclassification and model validation computations to establish incremental value; these studies showed less consistency with respect to added value. In conclusion, the literature assessing incremental value of BNP/NT-proBNP in ADHF populations is limited to seven studies evaluating only mortality outcomes and at moderate risk of bias. Although there were differences in the base risk prediction models, assay cutpoints, and lengths of follow-up, there was consistency in BNP/NT-proBNP adding incremental value in prediction models in ADHF patients.  相似文献   
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Previous randomized and observational studies on the efficacy of metformin in pregnancy to reduce incident gestational diabetes mellitus (GDM) in women at high risk (obesity, polycystic ovary syndrome [PCOS], or pregestational insulin resistance) have been conflicting and several groups are planning further randomized controlled trials (RCTs) to answer this question conclusively. This work assesses the efficacy of metformin in pregnancy to avert one outcome—incident GDM in women at high risk. We included RCTs comparing metformin with usual care or placebo controls in terms of incident GDM and recruiting women at high risk during early pregnancy. Eleven eligible trials enrolled 2370 adult women whose intervention arm consisted of metformin started at conception or before 20 weeks of gestation. Risk of GDM was similar in intervention compared with controls (risk ratio [RR] 1.03; 95% confidence interval [CI], 0.85‐1.24). The data were of sufficient quality meeting the criteria for consistency and directness. We conclude that metformin does not contribute to averting the GDM outcome in women at high risk when initiated in pregnancy. The evidence provided by this synthesis affirms that further broad clinical trials investigating this question are no longer needed.  相似文献   
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Several lines of evidence suggest that defects in telomere maintenance play a significant role in the initiation of genomic instability during carcinogenesis. Although the general concept of defective telomere maintenance initiating genomic instability has been acknowledged, there remains a critical gap in the direct evidence of telomere dysfunction in human solid tumors. To address this topic, we devised a multiplex PCR-based assay, termed TAR (telomere-associated repeat) fusion PCR, to detect and analyze chromosome end-to-end associations (telomere fusions) within human breast tumor tissue. Using TAR fusion PCR, we found that human breast lesions, but not normal breast tissues from healthy volunteers, contained telomere fusions. Telomere fusions were detected at similar frequencies during early ductal carcinoma in situ and in the later invasive ductal carcinoma stage. Our results provide direct evidence that telomere fusions are present in human breast tumor tissue and suggest that telomere dysfunction may be an important component of the genomic instability observed in this cancer. Development of this robust method that allows identification of these genetic aberrations (telomere fusions) is anticipated to be a valuable tool for dissecting mechanisms of telomere dysfunction.  相似文献   
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AIM: To describe the safety and efficacy of patterned laser trabeculoplasty (PLT) as an adjunctive treatment in primary open angle glaucoma (POAG) and ocular hypertension (OHT) after 18-month follow-up in Hispanic population. METHODS: This was a single-center, retrospective study. All patients with OHT or POAG who underwent PLT from June 2016 to August 2016 were included in the study. Investigated parameters were intraocular pressure (IOP), the number of hypotensive medications, visual acuity, laser parameters and postoperative complications. PLT success was defined as IOP reduction ≥20% without additional medications, laser, or surgery; or a reduction in the number of medications while maintaining IOP values. RESULTS: A total of 40 PLT-treated eyes (mean baseline IOP 20.3±1.7 mm Hg) of 24 patients were analyzed (age 63.4±7.3y). The mean IOP reductions from baseline across visits (months 1, 3, 6, 9, 12 and 18) ranged from 14.1% to 20.8%. Success rate after 18-month follow-up was 61.7% with a mean IOP of 16±3.2 mm Hg (P<0.001). The number of glaucoma medications per eye (preoperative 2.1±1.1 and postoperative 2.3±1.1) and the mean best corrected visual acuity (preoperative 0.10±0.22 and postoperative 0.11±0.22), remained stable (P=0.86 and 0.42, respectively). Complications included transient IOP spikes in 4 eyes (10%) and peripheral anterior synechiae in 7 eyes (17.5%). CONCLUSION: Mid-term results of PLT show that this procedure may be an effective and safe method for the management of patients with OHT or POAG as an adjunctive therapy.  相似文献   
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Polydimethyl siloxane (PDMS) based pressure sensitive adhesives (PSA) incorporating organo-clays at different loadings were fabricated via solution casting. Partially exfoliated nanocomposites were obtained for the hydroxyl terminated PDMS in ethyl acetate solvent as determined by X-ray diffraction and atomic force microscopy. Drug release studies showed that the initial burst release was substantially reduced and the drug release could be controlled by the addition of organo-clay. Shear strength and shear adhesion failure temperature (SAFT) measurements indicated substantial improvement in adhesive properties of the PSA nanocomposite adhesives. Shear strength showed more than 200% improvement at the lower clay loadings and the SAFT increased by about 21% due to the reinforcement provided by the nano-dispersed clay platelets. It was found that by optimizing the level of the organosilicate additive to the polymer matrix, superior control over drug release kinetics and simultaneous improvements in adhesive properties could be attained for a transdermal PSA formulation.  相似文献   
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肝外胆道肿瘤罕见,其中以横纹肌肉瘤最常见。横纹肌肉瘤是一种软组织恶性肌肉骨骼肿瘤,是儿童非常罕见的一种胆总管恶性肿瘤。它通常表现为阻塞性黄疸和/或瘙痒。如果肿瘤没有局部浸润邻近组织,其影像学表现则类似胆总管囊肿。因此,确诊通常是在手术时或术前通过活检。早期诊断、与胆总管囊肿鉴别、尽早开始治疗对延长患者生存时间有重要意义。该文报道1例10岁男童,反复阻塞性黄疸和发热,术前诊断为胆总管囊肿,术后确诊为胆总管胚胎性横纹肌肉瘤。经手术切除、术后化疗,该患儿预后良好。故必须了解这种罕见的肿瘤可以类似先天性胆总管囊肿,并且在儿童阻塞性黄疸的鉴别诊断时应加以考虑。  相似文献   
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