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71.
Georgia Robins Sadler Celine Marie Ko Jennifer Alisangco Bradley P Rosbrook Eric Miller Judith Fullerton 《Applied Nursing Research》2007,20(3):152-157
This article discusses issues to be considered by nurse researchers when groups should be used as the unit of randomization. Advantages and disadvantages are presented, with statistical calculations needed to determine the effective sample size. Examples of these concepts are presented using data from the Black Cosmetologists Promoting Health Program. Different hypothetical scenarios and their impact on sample size are also presented. Given the complexity of calculating the sample size when using groups as the unit of randomization, it is advantageous for researchers to work closely with statisticians when designing and implementing studies that anticipate the use of groups as the unit of randomization. 相似文献
72.
C. Marie C. Mossiat C. Gros T. Monteil J. Bralet 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1996,10(5):593-598
Summary Myocardial infarction was induced in rats by ligation of the left coronary artery. Treatment with TM1, a prodrug of SQ 28,603, an inhibitor of neutral endopeptidase (NEP, EC 3.4.24.11), was started 18–20 hours after ligation and was continued for 4 weeks (100 mg/kg, orally, twice daily). Morphological and biochemical parameters were assessed at the end of therapy. The treatment resulted in a significant reduction of heart hypertrophy, which was restricted to the parts of myocardium hemodynamically upstream of the infarcted left ventricle. The weights of the right ventricle and atria were reduced by 15–20%, whereas the treatment had no effect on the left ventricle and septum weights. Treatment led to an almost complete inhibition of plasma NEP activity and to a slight decrease (-14%, p<0.05) in plasma ACE activity. Plasma ANF level increased 3.8-fold after ligation, and treatment resulted in a slight (+29%) and nonsignificant additional increase in the ANF level. The amount of hydroxyproline in the right ventricle was enhanced by +207% in control ligated rats and by +140% (NS) in treated rats. These data indicate that prolonged NEP inhibition exerts a favorable effect in heart failure by reducing the development of right ventricular and atrial hypertrophy. These effects may result from an improvement in hemodynamic conditions, leading to a reduction in cardiac preload. 相似文献
73.
74.
Paul A. Demers Thomas L. Vaughan Thomas D. Koepsell Joseph L. Lyon G. Marie Swanson Raymond S. Greenberg Noel S. Weiss 《American journal of industrial medicine》1993,23(4):629-639
Lifetime job histories from a population-based, case-control study were analyzed to investigate the relationship between multiple myeloma and employment in various occupations and industries. Interviews were obtained from 89% (692) of eligible incident cases and 83% (1683) of eligible controls. An elevated risk was observed among persons ever employed as painters [odds ratio (OR) + 2.1, 95% confidence interval (CI) + 1.2–3.6], particularly for those employed for 10 or more years (OR + 4.1, 95% CI + 1.8–10.4). A small excess risk was observed among agricultural workers employed for 10 or more years (OR + 1.3, 95% CI + 1.0–2.2), with a higher relative risk observed among farm laborers (OR + 1.8, 95% CI + 1.0–4.0). Among agricultural workers who reported having been highly exposed to pesticides, the OR was 5.2 (95% CI + 1.6–21.1). Some evidence, based on smaller numbers, was also found to support an association with firefighting and employment in the petroleum- and coal-products manufacturing industries. Little evidence was found to support the previously noted association with wood exposure, and no evidence for an association with employment in the rubber or petroleum refining industries was found. This study lends further support to previously reported associations between multiple myeloma and employment among painters and agricultural workers. © 1993 Wiley-Liss, Inc. 相似文献
75.
Karly Hampshire Pierre‐Marie Martin Colleen Carlston Anne Slavotinek 《American journal of medical genetics. Part A》2020,182(8):1923-1932
Baraitser–Winter cerebrofrontofacial syndrome (BWCS) is a rare, autosomal dominant condition that is characterized by intellectual disability, distinctive craniofacial features, structural brain abnormalities, seizures, microcephaly, hearing loss, and ocular colobomas. The first three cases were described in 1988 by Baraitser and Winter and included two siblings and an unrelated third patient. Subsequently, causative missense variants in the ACTB and ACTG1 genes were identified, with de novo occurrence in patients with the condition. Herein, we describe two adult siblings who were born to unaffected parents and who were diagnosed with BWCS in their fourth and sixth decade of life following exome sequencing performed for intellectual disability. We review the literature reports of adult patients with BWCS to document the clinical features and phenotypic variability that can occur later in life. This is the first molecularly confirmed report of germline mosaicism in BWCS and one of only a few reports to describe two BWCS patients belonging to the same family. 相似文献
76.
Romain Guinamard Aurélien Chatelier Marie Demion Daniel Potreau Sylvie Patri Mohammad Rahmati Patrick Bois 《The Journal of physiology》2004,558(1):75-83
Cardiac arrhythmias, which occur in a wide variety of conditions where intracellular calcium is increased, have been attributed to the activation of a transient inward current ( I ti ). I ti is the result of three different [Ca]i -sensitive currents: the Na+ –Ca2+ exchange current, a Ca2+ -activated chloride current and a Ca2+ -activated non-selective cationic current. Using the cell-free configuration of the patch-clamp technique, we have characterized the properties of a Ca2+ -activated non-selective cation channel (NSCCa ) in freshly dissociated human atrial cardiomyocytes. In excised inside-out patches, the channel presented a linear I–V relationship with a conductance of 19 ± 0.4 pS. It discriminated poorly among monovalent cations (Na+ and K+ ) and was slightly permeable to Ca2+ ions. The channel's open probability was increased by depolarization and a rise in internal calcium, for which the K d for [Ca2+ ]i was 20.8 μ m . Channel activity was reduced in the presence of 0.5 m m ATP or 10 μ m glibenclamide on the cytoplasmic side to 22.1 ± 16.8 and 28.5 ± 8.6%, respectively, of control. It was also inhibited by 0.1 m m flufenamic acid. The channel shares several properties with TRPM4b and TRPM5, two members of the 'TRP melastatin' subfamily. In conclusion, the NSCCa channel is a serious candidate to support the delayed after-depolarizations observed in [Ca2+ ] overload and thus may be implicated in the genesis of arrhythmias. 相似文献
77.
Bojian Zheng Ming-Liang He King-Ling Wong Ching Tung Lum Leo L M Poon Ying Peng Yi Guan Marie C M Lin Hsiang-Fu Kung 《Journal of interferon & cytokine research》2004,24(7):388-390
We sought to investigate the anti-severe acute respiratory syndrome (SARS)-associated coronavirus (SCoV) activities of type I (alpha and beta) and type II (gamma) interferons (IFN) in vitro. Type I IFNs protected cells from cytopathic effects (CPE) induced by SCoV, and inhibited viral genomic RNA replication in FRhk-4 cells (measured by quantitative RT-PCR) in a dose-dependent manner. Intracellular viral RNA copies were reduced 50% by IFN-alpha at a concentration of 25 U/ml and by IFN-beta at a concentration of 14 U/ml. IFN-gamma had fewer effects on inhibition of viral infection and replication. The type I IFN receptor signaling pathway in host cells is mainly involved in the inhibition of SCoV infection and replication. Type I IFNs could be used as potential agents for anti-SARS treatment. 相似文献
78.
Peng?Dong Ling?Ling?Wong Sarah?Ng Marie?Loh Adrian?MondryEmail author 《BMC medical informatics and decision making》2004,4(1):21
Background
Critically Appraised Topics (CATs) are a useful tool that helps physicians to make clinical decisions as the healthcare moves towards the practice of Evidence-Based Medicine (EBM). The fast growing World Wide Web has provided a place for physicians to share their appraised topics online, but an increasing amount of time is needed to find a particular topic within such a rich repository.Methods
A web-based application, namely the CAT Crawler, was developed by Singapore's Bioinformatics Institute to allow physicians to adequately access available appraised topics on the Internet. A meta-search engine, as the core component of the application, finds relevant topics following keyword input. The primary objective of the work presented here is to evaluate the quantity and quality of search results obtained from the meta-search engine of the CAT Crawler by comparing them with those obtained from two individual CAT search engines. From the CAT libraries at these two sites, all possible keywords were extracted using a keyword extractor. Of those common to both libraries, ten were randomly chosen for evaluation. All ten were submitted to the two search engines individually, and through the meta-search engine of the CAT Crawler. Search results were evaluated for relevance both by medical amateurs and professionals, and the respective recall and precision were calculated.Results
While achieving an identical recall, the meta-search engine showed a precision of 77.26% (±14.45) compared to the individual search engines' 52.65% (±12.0) (p < 0.001).Conclusion
The results demonstrate the validity of the CAT Crawler meta-search engine approach. The improved precision due to inherent filters underlines the practical usefulness of this tool for clinicians.79.
Survey of the Distribution of a Newly Characterized Receptor for Advanced Glycation End Products in Tissues 总被引:33,自引:2,他引:33 下载免费PDF全文
Jerold Brett Ann Marie Schmidt Shi Du Yan Yu Shan Zou Elliott Weidman David Pinsky Roman Nowygrod Michael Neeper Craig Przysiecki Alan Shaw Antonio Migheli David Stern 《The American journal of pathology》1993,143(6):1699-1712
Advanced glycation end products (AGEs), the final products of nonenzymatic glycation and oxidation of proteins, are found in the plasma and accumulate in the tissues during aging and at an accelerated rate in diabetes. A novel integral membrane protein, termed receptor for AGE (RAGE), forms a central part of the cell surface binding site for AGEs. Using monospecific, polyclonal antibody raised to human recombinant and bovine RAGE, immunostaining of bovine tissues showed RAGE in the vasculature, endothelium, and smooth muscle cells and in mononuclear cells in the tissues. Consistent with these data, RAGE antigen and mRNA were identified in cultured bovine endothelium, vascular smooth muscle, and monocyte-derived macrophages. RAGE antigen was also visualized in bovine cardiac myocytes as well as in cultures of neonatal rat cardiac myocytes and in neural tissue where motor neurons, peripheral nerves, and a population of cortical neurons were positive. In situ hybridization confirmed the presence of RAGE mRNA in the tissues, and studies with rat PC12 pheochromocytes indicated that they provide a neuronal-related cell culture model for examining RAGE expression. Pathological studies of human atherosclerotic plaques showed infiltration of RAGE-expressing cells in the expanded intima. These results indicate that RAGE is present in multiple tissues and suggest the potential relevance of AGE-RAGE interactions for modulating properties of the vasculature as well as neural and cardiac function, prominent areas of involvement in diabetes and in the normal aging process. 相似文献
80.
Evolutionary genetic analysis of the emergence of epidemic Vibrio cholerae isolates on the basis of comparative nucleotide sequence analysis and multilocus virulence gene profiles 总被引:3,自引:0,他引:3 下载免费PDF全文
Vibrio cholerae, the causative agent of cholera, is a natural inhabitant of the aquatic ecosystem. We examined a unique collection of V. cholerae clinical and environmental isolates of widespread geographic distribution recovered over a 60-year period to determine their evolutionary genetic relationships based on analysis of two housekeeping genes, malate dehydrogenase (mdh) and a chaperonin (groEL). In addition, the phylogenetic distribution of 12 regions associated with virulence was determined. Comparative sequence analysis of mdh revealed that all V. cholerae O1 and O139 serogroup isolates belonged to the same clonal lineage. Single-strand conformational polymorphism (SSCP) analysis of these O1 and O139 strains at groEL confirmed the presence of an epidemic clonal complex. Of the 12 virulence regions examined, only three regions, Vibrio seventh pandemic island 1 (VSP-I), VSP-II, and RS1, were absent from all classical V. cholerae isolates. Most V. cholerae El Tor biotype and O139 serogroup isolates examined encoded all 12 virulence regions assayed. Outside of V. cholerae O1/O139 serogroup isolates, only one strain, VO7, contained VSP-I. Two V. cholerae El Tor isolates, GP155 and 2164-78, lacked both VSP-I and VSP-II, and one El Tor isolate, GP43, lacked VSP-II. Five non-O1/non-O139 serogroup isolates had an mdh sequence identical to that of the epidemic O1 and O139 strains. These isolates, similar to classical strains, lack both VSP-I and VSP-II. Four of the 12 virulence regions examined were found to be present in all isolates: hlyA, pilE, MSHA and RTX. Among non-O1/non-O139 isolates, however, the occurrence of the additional eight regions was considerably lower. The evolutionary relationships and multilocus virulence gene profiles of V. cholerae natural isolates indicate that consecutive pandemic strains arose from a common O1 serogroup progenitor through the successive acquisition of new virulence regions. 相似文献