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排序方式: 共有1687条查询结果,搜索用时 15 毫秒
61.
Wakim-Ghorayeb SF Keleshian SH Timson G Finan RR Najm P Irani-Hakime N Almawi WY 《American journal of hematology》2005,80(1):84-86
The association of the single nucleotide polymorphisms (SNPs) G1691A in coagulation factor V (FV)-Leiden and G20210A in prothrombin (PRT) genes with type 2 diabetes mellitus (T2DM) were analyzed in 112 T2DM patients (58 males, 54 females; mean age 55.24 +/- 13.5 years) and 249 healthy control subjects (118 males, 131 females; mean age 53.03 +/- 13.8 years). No association was found for FV-Leiden with T2DM, as the frequency of the G/G (82.1% vs. 85.5%), G/A (17.0% vs. 14.1%), and A/A (0.9% vs. 0.4%) genotypes was not different between patients and controls, respectively (P = 0.644). Similarly, lack of association of PRT G20210A with T2DM was seen among the population studied, and the frequency of the G/G (92.9% vs. 97.2%), G/A (6.3% vs. 2.8%), and A/A (0.9% vs. 0.0%) genotypes was similar among patients and controls, respectively (P = 0.094). Neither FV-Leiden nor PRT G20210A was associated with, and no evidence for interactions between these mutations was seen in, T2DM. 相似文献
62.
Writing epilepsy is a rare reflex syndrome in which seizures are triggered by writing. We describe a 33-year-old, right-handed man, with a history of juvenile absence epilepsy in remission and a family history of epilepsy, in whom myoclonic jerks precipitated exclusively by writing started at the age of 30. Intensive video/EEG monitoring during neuropsychological tests revealed, at about 1 minute after starting to write, a dystonic posture, followed by myoclonic jerks involving the right hand that shortly after became generalized. Concomitantly, the ictal EEG documented generalized hypersynchronous polyspike-wave discharges, maximal over the right parietocentral area. SPECT revealed an ictal hyperperfusion and interictal hypoperfusion over right parietofrontal regions, and fMRI showed extensive and intense left frontal, supplementary motor area activation, induced by writing. This case study provides some evidence supporting the hypothesis that the mechanism underlying writing-triggered seizures may be a generalized seizure process, with a focal cortical trigger zone, presumed to be the left frontal lobe as suggested by clinical and fMRI data. A relevant role played by the right hemisphere (right parietofrontal region) is postulated in the full-blown expression of reflex epileptogenesis, as supported by EEG and SPECT findings. 相似文献
63.
Logan RF Howarth GF West J Shepherd K Robinson MH Hardcastle JD 《European journal of gastroenterology & hepatology》2003,15(10):1097-1100
BACKGROUND AND AIMS: It has been reported that occult gastrointestinal bleeding as detected by faecal occult blood (FOB) testing can occur in coeliac disease. This study examines whether a positive FOB is a feature of coeliac disease and whether FOB-positive subjects need investigation for coeliac disease. METHODS: First, the records of patients on the Nottingham Register for Coeliac Disease were reviewed for positive FOB testing. Second, the Nottingham colorectal cancer screening trial database was also reviewed to examine how many coeliac patients on the Register had participated and to examine their FOB results. Finally, sera from 309 screening trial participants who were FOB-positive but had no colonic abnormality were screened for immunoglobulin A (IgA) gliadin and IgA endomysial and human tissue transglutaminase (tTG) IgA antibodies. RESULTS: Five of 590 patients on the Register had had FOB tests at the time of diagnosis; four had positive tests during investigation of diarrhoea and/or anaemia. Of 21 patients on the Register who had participated in the colorectal cancer screening trial, one had a positive FOB test and was found to have a rectal tubulo-villous adenoma. Of the 309 FOB-positive patients, 7% (22 subjects) were positive for IgA gliadin antibodies, but none had IgA endomysial antibodies detected and two subjects had positive human tTG antibody assays for coeliac disease. CONCLUSIONS: Occult gastrointestinal bleeding occurs in a small number of symptomatic coeliac disease patients before diagnosis, but is no more frequent in treated and undetected coeliac disease patients than in the general population. Unless there are other indications, coeliac disease does not need to be considered in the investigation of a positive FOB test. 相似文献
64.
Systolic orthostatic hypotension is related to lowered cognitive function: Findings from the Maine‐Syracuse Longitudinal Study 下载免费PDF全文
Rachael V. Torres BA Merrill F. Elias PhD Georgina E. Crichton PhD Gregory A. Dore PhD Adam Davey PhD 《Journal of clinical hypertension (Greenwich, Conn.)》2017,19(12):1357-1365
The aim of the present study was to examine the relationship between orthostatic changes in blood pressure (BP) and cognition, with consideration given to cardiovascular risk factors and lifestyle variables. The cross‐sectional analysis included 961 community‐dwelling participants of the Maine‐Syracuse Longitudinal Study, for whom BP clinic measures (five sitting, five recumbent, and five standing) were obtained. Eighteen percent of participants had orthostatic hypotension (fall in systolic BP ≥20 mm Hg or diastolic BP ≥10 mm Hg upon standing) and 6% had orthostatic hypertension (rise in systolic BP ≥20 mm Hg). Orthostatic hypotension and hypertension defined using traditional criteria were unrelated to cognition with covariate adjustment. However, an examination of systolic and diastolic BP change independently revealed that participants with systolic orthostatic hypotension had poorer global cognition, verbal memory, and scanning and tracking scores than those with normal systolic BP change. The authors conclude that systolic orthostatic hypotension is significantly associated with reduced cognitive function. 相似文献
65.
Jorge R. Calderon-Ticona Alvaro Taype-Rondan Georgina Villamonte L. Max Labán-Seminario Luis M. Helguero-Santín J. Jaime Miranda Maria Lazo-Porras 《Primary Care Diabetes》2021,15(3):488-494
ObjectiveTo characterize diabetes care across healthcare facilities in six Peruvian regions.MethodsCross-sectional study of patients with type 2 diabetes mellitus (T2DM), ranging from primary care facilities to hospital-based facilities, in six Peruvian regions. Data was collected by health staff trained between 2012 and 2016. We studied six diabetes care outcomes and four adequate diabetes care outcomes considering the healthcare facility as the exposure of interest. We estimated prevalence ratios (PR) and their 95% confidence intervals (95% CI) using Poisson regression with robust variance.ResultsData from 8879 patients with T2DM, mean age 59.1 years (SD ± 12.2), 53.6% males, was analyzed. Of these, 8096 (91.2%) were treated at primary care facilities. The proportions of patients who had HbA1c, LDL-c, and creatinine/microalbumin test performed increased with the setting of the healthcare facility. Overall, 39%–56% of patients had an adequate HbA1c control, being higher in hospital-based facilities with specialists in comparison to primary care facilities.ConclusionsWe observed that the higher the setting of the facility, the higher the rate of the assessed diabetes care outcomes and adequate diabetes care for four of the six targets (fasting glucose, HbA1c, LDL-c and creatinine or microalbumin) and for three of the four targets (glucose≤130 mg/dL, HbA1c ≤7%(53 mmol/mol) and LDL-c <100 mg/dL), respectively. Substantial gaps were observed at the primary care facilities, calling for the strengthening of diabetes care. 相似文献
66.
G. Tzanakaki M. Tsopanomichalou K. Kesanopoulos R. Matzourani M. Sioumala A. Tabaki J. Kremastinou 《Clinical microbiology and infection》2005,11(5):386-390
Rapid, accurate and inexpensive diagnosis of bacterial meningitis is critical for patient management. This study describes the development and evaluation of a multiplex PCR assay for the detection of Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae type b, which globally account for 90% of cases of bacterial meningitis. The single-tube assay, based on the ctrA, ply and bex targets, respectively, enabled detection of 5-10 pg DNA. When the assay was tested with clinical samples (n = 425), its sensitivity for the three targets was 93.9%, 92.3% and 88%, respectively, while the overall specificity and positive predictive value of the assay was 100%. The negative predictive value was 99.1-99.5%. The methodology permits rapid and accurate detection of the three main pathogens that cause bacterial meningitis. 相似文献
67.
Mooney E Mackle JN Blond DJ O'Cearbhaill E Shaw G Blau WJ Barry FP Barron V Murphy JM 《Biomaterials》2012,33(26):6132-6139
Once damaged, cardiac muscle has little intrinsic repair capability due to the poor regeneration potential of remaining cardiomyocytes. One method of overcoming this issue is to deliver functional cells to the injured myocardium to promote repair. To address this limitation we sought to test the hypothesis that electroactive carbon nanotubes (CNT) could be employed to direct mesenchymal stem cell (MSC) differentiation towards a cardiomyocyte lineage. Using a two-pronged approach, MSCs exposed to medium containing CNT and MSCs seeded on CNT based polylactic acid scaffolds were electrically stimulated in an electrophysiological bioreactor. After electrical stimulation the cells reoriented perpendicular to the direction of the current and adopted an elongated morphology. Using qPCR, an upregulation in a range of cardiac markers was detected, the greatest of which was observed for cardiac myosin heavy chain (CMHC), where a 40-fold increase was observed for the electrically stimulated cells after 14 days, and a 12-fold increase was observed for the electrically stimulated cells seeded on the PLA scaffolds after 10 days. Differentiation towards a cardioprogenitor cell was more evident from the western blot analysis, where upregulation of Nkx2.5, GATA-4, cardiac troponin t (CTT) and connexin43 (C43) was seen to occur. This was echoed in immunofluorescent staining, where increased levels of CTT, CMHC and C43 protein expression were observed after electrical stimulation for both cells and cell-seeded scaffolds. More interestingly, there was evidence of increased cross talk between the cells as shown by the pattern of C43 staining after electrical stimulation. These results establish a paradigm for nanoscale biomimetic cues that can be readily translated to other electroactive tissue repair applications. 相似文献
68.
Jiwani S Wang Y Dowd GC Gianfelice A Pichestapong P Gavicherla B Vanbennekom N Ireton K 《Infection and immunity》2012,80(3):1252-1266
The bacterial pathogen Listeria monocytogenes causes food-borne illnesses resulting in gastroenteritis, meningitis, or abortion. Listeria promotes its internalization into some human cells through binding of the bacterial surface protein InlB to the host receptor tyrosine kinase Met. The interaction of InlB with the Met receptor stimulates host signaling pathways that promote cell surface changes driving bacterial uptake. One human signaling protein that plays a critical role in Listeria entry is type IA phosphoinositide 3-kinase (PI 3-kinase). The molecular mechanism by which PI 3-kinase promotes bacterial internalization is not understood. Here we perform an RNA interference (RNAi)-based screen to identify components of the type IA PI 3-kinase pathway that control the entry of Listeria into the human cell line HeLa. The 64 genes targeted encode known upstream regulators or downstream effectors of type IA PI 3-kinase. The results of this screen indicate that at least 9 members of the PI 3-kinase pathway play important roles in Listeria uptake. These 9 human proteins include a Rab5 GTPase, several regulators of Arf or Rac1 GTPases, and the serine/threonine kinases phosphoinositide-dependent kinase 1 (PDK1), mammalian target of rapamycin (mTor), and protein kinase C-ζ. These findings represent a key first step toward understanding the mechanism by which type IA PI 3-kinase controls bacterial internalization. 相似文献
69.
The CD300c (CMRF-35A) and CD300a (CMRF-35H) molecules are leukocyte surface proteins that are part of a larger family of immunoregulatory molecules encoded by a gene complex on human chromosome 17. The CMRF-35 monoclonal antibody binds to an epitope common to both molecules, expressed on most human leukocyte populations, apart from B lymphocytes and a subpopulation of CD4(+) and CD8(+) T lymphocytes. We describe the CMRF-35(pos) and CMRF-35(-) fractions of CD4(+) T lymphocytes. The CMRF-35(pos) fraction can further be divided into CMRF-35(++) and CMRF-35(+)CD4(+) T lymphocyte subpopulations. Resting peripheral CD4(+) T lymphocytes express CD300a mRNA and very low amounts of CD300c. Activation results in an initial decrease in CD300a gene expression before an increase in both CD300a and CD300c gene expression. The up-regulated expression of these genes was associated with increased CMRF-35 binding to activated T lymphocytes. The CMRF-35(-) fraction of CD4(+) T lymphocytes proliferated to a greater extent than the CMRF-35(pos) fraction, in response to mitogens or allogeneic antigen. The poor proliferation of the CMRF-35(pos) CD4(+) in response to mitogens was explained by increased apoptosis within this subpopulation. The recall antigen, tetanus toxoid, stimulated the CMRF-35(++)CD4(+)CD45RO(+) but not the CMRF-35(-)CD4(+)CD45RO(+) subpopulation. Resting CMRF-35(++) CD4(+) lymphocytes express low levels of IFN-gamma mRNA. Within 18 h following in vitro activation, CMRF-35(++) CD4(+) lymphocytes express more IFN-gamma mRNA and protein compared with the CMRF-35(-)CD4(+) lymphocytes, however, after 24 h, both the CMRF-35(+) and CMRF-35(-)CD4(+) T lymphocytes were able to produce IFN-gamma. The CMRF-35(++)CD4(+) T lymphocyte population contains the Th(1) memory effector cells. 相似文献
70.
Jones AM Howarth KM Martin L Gorman M Mihai R Moss L Auton A Lemon C Mehanna H Mohan H Clarke SE Wadsley J Macias E Coatesworth A Beasley M Roques T Martin C Ryan P Gerrard G Power D Bremmer C;TCUKIN Consortium Tomlinson I Carvajal-Carmona LG 《Journal of medical genetics》2012,49(3):158-163
Five single nucleotide polymorphisms (SNPs) associated with thyroid cancer (TC) risk have been reported: rs2910164 (5q24); rs6983267 (8q24); rs965513 and rs1867277 (9q22); and rs944289 (14q13). Most of these associations have not been replicated in independent populations and the combined effects of the SNPs on risk have not been examined. This study genotyped the five TC SNPs in 781 patients recruited through the TCUKIN study. Genotype data from 6122 controls were obtained from the CORGI and Wellcome Trust Case-Control Consortium studies. Significant associations were detected between TC and rs965513A (p=6.35×10(-34)), rs1867277A (p=5.90×10(-24)), rs944289T (p=6.95×10(-7)), and rs6983267G (p=0.016). rs6983267 was most strongly associated under a recessive model (P(GG vs GT + TT)=0.004), in contrast to the association of this SNP with other cancer types. However, no evidence was found of an association between rs2910164 and disease under any risk model (p>0.7). The rs1867277 association remained significant (p=0.008) after accounting for genotypes at the nearby rs965513 (p=2.3×10(-13)) and these SNPs did not tag a single high risk haplotype. The four validated TC SNPs accounted for a relatively large proportion (~11%) of the sibling relative risk of TC, principally owing to the large effect size of rs965513 (OR 1.74). 相似文献