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排序方式: 共有551条查询结果,搜索用时 31 毫秒
81.
Lilia R. Lukowsky Claudia Der-Martirosian William Neil Steers Kiran S. Kamble Aram Dobalian 《Viruses》2022,14(2)
Background. Previous studies examining the early spread of COVID-19 have used influenza-like illnesses (ILIs) to determine the early spread of COVID-19. We used COVID-19 case definition to identify COVID-like symptoms (CLS) independently of other influenza-like illnesses (ILIs). Methods. Using data from Emergency Department (ED) visits at VA Medical Centers in CA, TX, and FL, we compared weekly rates of CLS, ILIs, and non-influenza ILIs encounters during five consecutive flu seasons (2015–2020) and estimated the risk of developing each illness during the first 23 weeks of the 2019–2020 season compared to previous seasons. Results. Patients with CLS were significantly more likely to visit the ED during the first 23 weeks of the 2019–2020 compared to prior seasons, while ED visits for influenza and non-influenza ILIs did not differ substantially. Adjusted CLS risk was significantly lower for all seasons relative to the 2019–2020 season: RR15–16 = 0.72, 0.75, 0.72; RR16–17 = 0.81, 0.77, 0.79; RR17–18 = 0.80, 0.89, 0.83; RR18–19 = 0.82, 0.96, 0.81, in CA, TX, and FL, respectively. Conclusions. The observed increase in ED visits for CLS indicates the likely spread of COVID-19 in the US earlier than previously reported. VA data could potentially help identify emerging infectious diseases and supplement existing syndromic surveillance systems. 相似文献
82.
Tomasz Laskus MD PhD Dr. Jorge Rakela MD Russel H. Wiesner MD Jeffery L. Steers MD David H. Persing MD PhD 《Digestive diseases and sciences》1994,39(8):1677-1682
We studied eight patients who had orthotopic liver transplantation for fulminant hepatic failure in the course of acute non-A, non-B hepatitis. HBV DNA was searched for extensively in the liver tissue by PCR using several sets of primers in conventional and heminested reactions. All patients were negative for HBV DNA in liver tissue by all assays employed; furthermore, they were negative for HEV RNA, HCV RNA, and HBV DNA in serum. Although the causative role of HEV and HCV in fulminant non-A, non-B hepatitis cannot be excluded, our data do not support a causative association between this syndrome and HBV infection.This study was supported by Grant CR20 from the Mayo Clinic and Foundation. D.H.P. is supported by Public Health Service grants AI 32403, AR 41497, and AI 30548 from the National Institutes of Health. 相似文献
83.
Ambiguous phenotypes and genotypes in 16 children with acute leukemia as characterized by multiparameter analysis 总被引:1,自引:0,他引:1
Ludwig WD; Bartram CR; Ritter J; Raghavachar A; Hiddemann W; Heil G; Harbott J; Seibt-Jung H; Teichmann JV; Riehm H 《Blood》1988,71(6):1518-1528
Ambiguous phenotypes and genotypes were observed in 16 children with acute leukemia. Surface marker, cytogenetic, molecular genetic, and DNA flow cytometric analyses as well as standard morphologic and cytochemical studies were used to divide the patients into three groups. The first group comprised five children with acute leukemia whose blast cells were morphologically lymphoid, while immunophenotyping disclosed simultaneous expression of early pre-B cell and myeloid features. Molecular genetic studies showed evidence of heavy-chain immunoglobulin (Ig) gene rearrangements in all patients. Cytogenetic data, available in three of these children, revealed t(4;11). In five of the 16 patients, morphologic and surface marker analyses indicated the coexistence of two separate cell populations, one with myeloid and the other with early pre-B cell features. Further evidence of B cell commitment in these patients was provided by demonstration of Ig heavy-chain gene rearrangements in all five patients. Surprisingly, one of the five patients showed oligoclonal Ig heavy-chain as well as monoclonal gene rearrangement for the beta chain of the T cell receptor (beta-TCR). The last group consisted of four cases with otherwise typical acute lymphoblastic leukemia (ALL), early pre-B cell phenotype, and coexpression of myeloid or T cell-associated antigens, and two children with unequivocal acute myeloid leukemia (AML) and coexpression of T cell antigens. Gene rearrangement of Ig heavy-chain could be demonstrated in five of six patients, additional Ig light-chain gene rearrangement in two children with ALL, and bigenotypic features (Ig heavy-chain and beta-TCR gene rearrangement) in one patient. In none of the 16 patients did flow cytometry disclose clonal abnormalities of leukemic cell DNA content. Based on these findings, we suggest that malignant transformation in the first and second group of patients took place at a stage ontogenetically close to the pluripotent stem cell, whereas ambiguous phenotypes in the third group resulted from aberrant gene expression or insufficient reagent specificity. 相似文献
84.
85.
Mendelow AD Timothy J Steers JW Lecky F Yates D Bouamra O Woodford M Hutchinson PJ 《Lancet》2008,372(9639):685-687
86.
No evidence of association between apolipoprotein E genotype and phenotypic severity in childhood onset proximal spinal muscular atrophy. 总被引:1,自引:0,他引:1
The survival motor neuron (SMN) gene is present in two copies on chromosome 5q13 and the evidence is now compelling that mutations in the telomeric copy (SMNt) of the gene underlie childhood onset proximal spinal muscular atrophy (SMA). There is a correlation between the number of centromeric SMN gene copies (SMNc) and the clinical severity of the disease but this relationship is not absolute. Allelic variants of the apolipoprotein E (APOE) gene encoded on chromosome 19q are known to influence the prognosis and risk in a number of neurological disorders. We have therefore genotyped 166 unrelated cases of SMA to determine whether the presence of specific APOE genotypes correlates with severity of disease. The study failed to show the influence of any particular APOE genotype on disease severity, with specifically APOE epsilon4 being no more common in the milder SMA forms and APOE epsilon2 not over represented in type I SMA. A limited study of 23 SMA families also failed to show any influence of APOE genotype on SMA disease severity. Factors other than APOE genotype must therefore be responsible for determining SMA disease severity. 相似文献
87.
David B. Clemow Richard McCarty William D. Steers Jeremy B. Tuttle 《Neurourology and urodynamics》1997,16(4):293-303
Elevated nerve growth factor secreted by bladder smooth muscle may be associated with noradrenergic hyperinnervation of the bladder and hyperactive voiding in spontaneously hypertensive rats (SHR) and rats with bladder outlet obstruction. The present study was undertaken to determine if changes occur in efferent and afferent pathways supplying the SHR bladder similar to those in rats with bladder outlet obstruction. Fluoro-Gold (FG) retrograde tracing studies were conducted to examine the postganglionic efferent limb (major pelvic ganglion; MPG) and sensory afferent limb (L1, L2, L6, and S1 dorsal root ganglion; DRG) of the micturition reflex pathway of the SHR and Wistar-Kyoto (WKY) normotensive rat. A significant increase in cross sectional area profiles for labeled neurons in the MPG was observed in SHRs (830.5 ± 9.0 μm2) as compared to WKYs (736.3 ± 16.6 μm2). Neuronal cell areas in L2 (1,010.9 ± 18.6 μm2) and S1 (1,024.6 ± 28.3 μm2) of SHRs were significantly larger than those of WKYs (L2, 865.3 ± 12.6 μm2; S1, 778.3 ± 11.2 μm2). There was an increase in number of labeled cells in L6 within SHRs over WKYs. These results provide evidence that both efferent and afferent changes in neuronal innervation of the bladder occur in SHRs. The SHR strain may represent a genetic model to study changes in micturition reflex pathways that result from alterations in neuronal morphology such as those that occur with urethral outlet obstruction. Neurourol. Urodynam. 16:293–303, 1997. © 1997 Wiley-Liss, Inc. 相似文献
88.
Coleman CC; Posalaky IP; Robinson JD; Payne WD; Vlodaver ZA; Amplatz K 《Radiology》1989,170(2):391-394
The mode of action of the Kensey catheter, a new atheroablation device, was investigated. Fresh above-the-knee amputated legs were used for recanalization of the superficial femoral artery. The variables used were identical to those of clinical trials, including a rotational speed of 50,000 rpm and an injection rate of 40 mL/min. The debris produced by the catheter was studied cytologically, and the arterial segments were examined histologically. The particle size in the debris ranged from 1 to 2,000 microns. The softer plaques produced a fine fibrin dust background with long strips of intima ranging from 10 to 2,000 microns. Complicated calcified plaques produced larger background material (10-120 microns) but smaller strips of intima (50-800 microns). Dissections and perforations occurred. Some of the debris produced by the atheroablation process was used to embolize a canine heart and kidney. Small focal infarctions were found in the heart, and large and multiple infarcts were seen in the kidney. In clinical studies the debris appears to be tolerated in the lower extremities. Its safety in the kidney and heart are questioned. 相似文献
89.
PO Chappuis N Hamel A-J Paradis J Deschênes A Robidoux C Potvin J Cantin P Tonin P Ghadirian WD Foulkes 《Clinical genetics》2001,59(6):418-423
The frequency of BRCA1 and BRCA2 mutations in women with breast cancer varies according to the age at diagnosis, family history of cancer, and ethnicity/country of origin. We set out to estimate the frequency of seven previously described founder mutations in BRCA1 and BRCA2 in all eligible French Canadian women diagnosed with invasive breast cancer at one Montreal hospital over a 20-month period. One hundred and ninety-two patients were eligible and 127 (66.2%) provided blood for genetic testing. We identified 4 women who carried a founder mutation (3.1%, 95% confidence interval 0.9-7.9%) in this population. Interestingly, all the mutations were in BRCA2. The mean age at diagnosis for mutation carriers was 51.2 years (range 49.1-53.5). Two of these 4 cases were lobular invasive carcinomas and 2 were ductal carcinomas, histological grade 1 or 2. Despite a small tumor size (< or =20 mm), axillary nodal involvement was present in 3 women. Estrogen receptors were strongly expressed in all cases. Two of the 4 cases reported a strong family history of breast cancer, but a family history of site-specific breast cancer was a relatively poor indicator of the presence of BRCA2 mutations. The absence of BRCA1 mutations may be a result of chance, but may also reflect different geographical origins of the most common BRCA1 mutations within the French Canadian population. 相似文献
90.
目的:观察基因工程技术构建人骨形态发生蛋白4复制缺陷腺病毒的成骨效果。方法:实验于2006-03/08在安徽医科大学第一附属医院实验动物中心完成。实验分组:选取普通级雄性SD大鼠30只,体质量(200±10)g,全部动物胫骨上端部分分别造成8mm×5mm长方形缺损。采用自身对照法,右侧骨缺损为实验组,左侧骨缺损为对照组。实验组植入人骨形态发生蛋白4复制缺陷腺病毒复合明胶海绵,对照组植入单纯明胶海绵。实验评估:术后分别于4,6,8周麻醉后处死10只动物,取材行X线、组织病理、免疫组织化学、透视电镜检查,观察成骨情况。结果:纳入30只大鼠,全部进入结果分析。①大鼠胫骨缺损X线、组织病理学检查结果:术后8周实验组和对照组骨缺损均得到修复,但实验组无论从成骨时间、成骨效果、新生骨量等方面都要优于对照组。其中各时间点实验组骨密度明显高于对照组,差异有显著性意义[4周:(95.91±16.33),(87.93±11.52);6周:(128.34±10.64),(102.41±9.81);8周:(138.36±10.49),(121.56±9.63);P<0.01]。各时间点实验组新生骨占骨缺损面积比明显高于对照组,差异有显著性意义[4周:(41.39±5.65)%,(26.58±5.62)%;6周:(80.35±7.25)%,(65.41±6.52)%;8周:(96.45±2.76)%,(82.22±7.30)%;P<0.01]②术后4周免疫组织化学染色结果:实验组软骨及骨痂内呈强阳性反应,而对照组骨痂内骨形态发生蛋白4表达微弱。结论:人骨形态发生蛋白4重组腺病毒具有良好的成骨活性,骨形态发生蛋白4直接转基因治疗能够加快骨缺损的修复。 相似文献