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Terrell DR Beebe LA Neas BR Vesely SK Segal JB George JN 《American journal of hematology》2012,87(9):848-852
To determine the prevalence of immune thrombocytopenia (ITP) in Oklahoma regardless of age, clinical characteristics, insurance status, and source of health care. Patients with ITP were identified by the administrative code ICD‐9‐CM 287.3 in Oklahoma hematologists' offices for a 2‐year period, 2003–2004. Prevalence was estimated separately for children (<16 years old) and adults because of their distinct clinical characteristics. Oklahoma census data for 2000 was used as the denominator. Eighty‐seven (94%) of 93 eligible Oklahoma hematologists participated; 620 patients with ITP were identified. The average annual prevalences were as follows: 8.1 (95% CI: 6.7–9.5) per 100,000 children, 12.1 (95% CI: 11.1–13.0) per 100,000 adults, and 11.2 (95% CI: 10.4–12.0) per 100,000 population. Among children and adults less than age 70 years, the prevalence was greater among women. Among adults aged 70 years and older, the prevalence was greater among men. The highest prevalence of ITP was among men age 80 years and older. These data document for the first time the prevalence of ITP regardless of age, clinical characteristics, insurance status, and source of health care. The methodology developed for this prevalence analysis may be adaptable for epidemiologic studies of other uncommon disorders which lack specific diagnostic criteria and are treated primarily by medical specialists. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc. 相似文献
23.
Froehlich-Zahnd R George JN Vesely SK Terrell DR Aboulfatova K Dong JF Luken BM Voorberg J Budde U Sulzer I Lämmle B Kremer Hovinga JA 《Haematologica》2012,97(2):297-303
Background
Severe ADAMTS13 deficiency is a critical component of the pathogenesis of idiopathic thrombotic thrombocytopenic purpura but is found only in about 60% of patients clinically diagnosed with this disease.Design and Methods
Over a period of 8 years and six episodes of thrombotic thrombocytopenic purpura we studied the evolution of the anti-ADAMTS13 antibody response in a patient using different ADAMTS13 assays and epitope mapping.Results
Anti-ADAMTS13 autoantibodies were found in all episodes but were inhibitory only in the last two episodes. In a flow-based assay, normal ADAMTS13 activity was found only during the first disease episode, while ADAMTS13 activity was normal using a static assay in episodes 1 and 3, and severely deficient in the last two episodes. Fluorescence evolution in a modified fluorescence resonance energy transfer assay using a von Willebrand factor A2 domain peptide substrate was linear in episodes 1, 5 and 6, but increased exponentially in episodes 3 and 4. Despite the variable functional characteristics of the anti-ADAMTS13 autoantibodies, their principal epitope was the ADAMTS13 spacer domain in all episodes.Conclusions
The patient is unique as he displayed features of maturation or shaping of the anti-ADAMTS13 autoantibody response during the course of multiple episodes of thrombotic thrombocytopenic purpura. Anti-ADAMTS13 autoantibodies may be important in vivo despite normal ADAMTS13 activity in routine assays. Consequently, treatment decisions should not be based solely on activity assay results. 相似文献24.
Human papillomavirus (HPV) infections have received considerable attention in recent years. Of the 120 or so known types of the virus, some cause a variety of benign wart‐like lesions of the skin and genital and oral mucosae, whilst others are aetiologically associated with cervical and anogenital cancers. Recent epidemiologic evidence suggests that HPV may also be an independent risk factor for oropharyngeal cancer. In this context it has been suggested that HPV virus may modulate the process of carcinogenesis in some tobacco and alcohol induced oropharyngeal cancers and act as the primary oncogenic agent for inducing carcinogenesis among non‐smokers. Dental practitioners have a major role in detecting all lesions of the oral mucosa caused, or possibly caused, by HPV. This paper briefly reviews the current state of knowledge of molecular and clinical aspects of HPV infections of the oral mucosa. 相似文献
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Sarah M. Wilson Amie R. Newins Alyssa M. Medenblik Nathan A. Kimbrel Eric A. Dedert Terrell A. Hicks Lydia C. Neal Jean C. Beckham Patrick S. Calhoun 《Women's health issues》2018,28(6):514-523
Objectives
Prenatal smoking is the leading preventable cause of poor obstetric outcomes, yet treatment options are limited. Past reviews of prenatal smoking cessation have often grouped all counseling into a single category, which ignores the fact that psychotherapy is distinct from brief counseling. The objective of this study was to compare the effect sizes of two intensive interventions for prenatal smoking cessation: contingency management (i.e., financial incentives for abstinence) and psychotherapy.Methods
A systematic search for randomized controlled trials testing the efficacy of contingency management or psychotherapy was completed using PubMed, PsycINFO, Web of Science, the Cochrane Library, and EMBASE. Independent raters extracted data and assessed trials for risk of bias. Treatment effects were analyzed for three times points: late pregnancy, early postpartum, and late postpartum.Results
The search yielded 22 studies, and meta-analytic results indicated that interventions (compared with control groups) generally increased the odds of abstinence. Moderator analyses indicated that intervention type (contingency management vs. psychotherapy) accounted for variability in effect sizes. When comparing treatment type, effects of contingency management interventions were significantly greater than those of psychotherapeutic interventions. Although psychotherapy did not affect smoking abstinence, contingency management interventions had significant treatment effects at all three time points.Conclusions
Contingency management seems to be a safe and efficacious prenatal smoking cessation treatment. Although psychotherapy alone did not show an effect on prenatal smoking abstinence, future research may seek to combine this approach with contingency management to promote prenatal smoking cessation. 相似文献27.
Platelet-derived growth factor (PDGF) is a potent mitogen for many cultured connective tissue cells. It is present in concentrated form within the platelet alpha-granules and is believed to be released during platelet degranulation at sites of vascular injury. We have used a sensitive radioreceptor assay to measure PDGF levels in whole blood serum from normal humans [17.5 +/- 3.1 (SD) ng/mL] and baboons (2.7 +/- 1.2 ng/mL). PDGF was not detected in plasma from either species. In addition, plasma was found to substantially reduce the ability of added purified PDGF to bind to the cell surface PDGF receptor on cultured cells, suggesting that plasma may contain a PDGF-binding protein that would serve to inactivate PDGF released into plasma. Calculations of PDGF concentrations in serum have been corrected for the effects of the binding protein. 125I-PDGF injected intravenously into normal baboons was cleared rapidly from the plasma (t1/2 = two minutes). The rapid clearance of 125I-PDGF did not result from iodination damage, as purified unlabeled PDGF was cleared with comparable kinetics. The rapid clearance of purified and iodinated PDGF did not result from changes in PDGF structure during purification or from removal of PDGF-associated proteins during purification, as PDGF present in freeze-thaw lysates of fresh platelets was cleared equally rapidly. We conclude that release of PDGF at sites of vascular injury would greatly increase the local concentration of PDGF and that PDGF not localized to the site of injury would be rapidly cleared from the circulation. 相似文献
28.
Chong SK Lou Q Zollinger TW Rabinowitz S Jibaly R Tolia V Elitsur Y Gold BD Rosenberg A Johnson A Elkayam O Rosenthal P Gilger M Li BU Peacock JS 《The American journal of gastroenterology》2003,98(10):2162-2168
OBJECTIVES: The purpose of this study was to determine the prevalence of serum antibodies directed against Helicobacter pylori (H. pylori) in children referred to children's hospitals or medical centers throughout the United States. METHODS: This multisite cross-sectional prospective study involved 992 children from 12 states using a validated anti-H. pylori IgG enzyme immunoassay. The children were recruited into two groups: those without any GI complaints (non-GI referral, n = 619) and those who were referred for endoscopy because of abdominal pain (GI referral, n = 373). RESULTS: GI referral children had a higher rate of seropositivity (22.5%) than non-GI referral children (14.1%) from the same geographic regions. In both groups, older children were more likely to be seropositive for H. pylori, as were nonwhite children and those with lower socioeconomic status. H. pylori seropositivity rates were higher in GI referral children with four or more household members (relative risk [RR] = 1.47; CI 1.01-2.14). Multivariate analysis controlling for age, ethnicity, and household income, showed that presence of GI symptoms were associated with a nearly 2-fold risk for H. pylori seropositivity (odds ratio = 1.77, CI 1.27-2.47). Epigastric pain (RR = 2.21; CI = 1.33-3.66) and having three or more episodes of abdominal pain in the last 3 months (RR = 0.59, CI = 0.35-0.99) were the only specific symptoms significantly associated with H. pylori seropositivity. CONCLUSIONS: The H. pylori seropositivity rate of GI referral children with symptoms of abdominal pain was significantly higher. H. pylori infection in early childhood was found to be associated primarily with the child's household size and socioeconomic status. 相似文献
29.
30.
Ramesh Y. Adhikari Jack Terrell James Targos Kenneth A. Huffman Huihui Wang Joseph Cradlebaugh 《RSC advances》2019,9(47):27289
Electronic waste (e-waste) is a growing problem in the world due to increasing consumption and subsequent discarding of electronic devices. One of the ways to address this problem is to develop electronics made up of biodegradable components. Leaves are readily available, biodegradable and can be found with various types of architecture of the vascular conduits within. We investigated the possibility of developing electronic components based on leaves of a monocotyledon plant by introducing a conducting polymer inside the vascular conduits. We were able to construct conducting wires in those conduits extending to centimeters in length within a leaf. Furthermore, we were able to demonstrate the construction of a supercapacitor within a leaf by using the conducting conduits as electrodes. These results suggest the possibility of constructing embedded electronic components within leaves which may provide an alternative towards the development of biodegradable electronics.Plant leaves were used to construct conducting channels and supercapacitors within. 相似文献