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131.
Fatma Meri? Y?lmaz Rabia Kahveci Altan Aksoy Emine ?zer Kucuk Tezcan Ak?n Joseph Lazar Mathew Catherine Meads Nurullah Zengin 《PloS one》2016,11(4)
ObjectivesEliminating unnecessary laboratory tests is a good way to reduce costs while maintain patient safety. The aim of this study was to define and process strategies to rationalize laboratory use in Ankara Numune Training and Research Hospital (ANH) and calculate potential savings in costs.MethodsA collaborative plan was defined by hospital managers; joint meetings with ANHTA and laboratory professors were set; the joint committee invited relevant staff for input, and a laboratory efficiency committee was created. Literature was reviewed systematically to identify strategies used to improve laboratory efficiency. Strategies that would be applicable in local settings were identified for implementation, processed, and the impact on clinical use and costs assessed for 12 months.ResultsLaboratory use in ANH differed enormously among clinics. Major use was identified in internal medicine. The mean number of tests per patient was 15.8. Unnecessary testing for chloride, folic acid, free prostate specific antigen, hepatitis and HIV testing were observed. Test panel use was pinpointed as the main cause of overuse of the laboratory and the Hospital Information System test ordering page was reorganized. A significant decrease (between 12.6–85.0%) was observed for the tests that were taken to an alternative page on the computer screen. The one year study saving was equivalent to 371,183 US dollars.ConclusionHospital-based committees including laboratory professionals and clinicians can define hospital based problems and led to a standardized approach to test use that can help clinicians reduce laboratory costs through appropriate use of laboratory tests. 相似文献
132.
Gupta S Vijayaraghavan S Uzer G Judex S 《American journal of physiology. Regulatory, integrative and comparative physiology》2012,303(2):R159-R167
A single exposure to mechanical unloading can result in significant bone loss, but the consequences of multiple exposures are largely unknown. Within a 18-wk period, adult C57BL/6 male mice were exposed to 2 wk of hindlimb unloading (HLU) followed by 4 wk of reambulation (RA) once (1x-HLU), twice (2x-HLU), or three times (3x-HLU), or served as ambulatory age-matched controls. In vivo μCT longitudinally tracked changes in trabecular and cortical compartments of the femur. Normally ambulating control mice experienced significant age-related loss in trabecular bone volume fraction throughout the course of the experiment. This loss was compounded by HLU with 2x- and 3x-HLU mice experiencing a 27% and 24% greater reduction in trabecular bone and a 60% and 63% inhibition of age-related trabecular thickening. The recovery of cortical bone was also incomplete during each 4-wk RA period and, at completion of the experiment, cortical area in 3x-HLU mice was 5% smaller than in control and 1x-HLU. When eliminating age as a confounding variable, comparison between individual HLU/RA cycles showed that the magnitude of the response diminished during subsequent exposures. The extent of trabecular thinning in mice unloaded for the first time was 1.6-fold greater than the second time and nearly twofold greater than the third time. Similarly, the increase in trabecular thickness during the first RA cycle was twofold greater than during the second and third RA cycle. Together, our data demonstrate that even though multiple exposures to mechanical unloading are more detrimental than a single unloading period, bone's mechanosensitivity is reduced with consecutive unloading/reambulation cycles. 相似文献
133.
Helen M. Regan H. Reşit Akçakaya Scott Ferson Karen V. Root Steve Carroll Lev R. Ginzburg 《人类与生态风险评估》2003,9(4):889-906
The selection of the most appropriate model for an ecological risk assessment depends on the application, the data and resources available, the knowledge base of the assessor, the relevant endpoints, and the extent to which the model deals with uncertainty. Since ecological systems are highly variable and our knowledge of model input parameters is uncertain, it is important that models include treatments of uncertainty and variability, and that results are reported in this light. In this paper we discuss treatments of variation and uncertainty in a variety of population models. In ecological risk assessments, the risk relates to the probability of an adverse event in the context of environmental variation. Uncertainty relates to ignorance about parameter values, e.g., measurement error and systematic error. An assessment of the full distribution of risks, under variability and parameter uncertainty, will give the most comprehensive and flexible endpoint. In this paper we present the rationale behind probabilistic risk assessment, identify the sources of uncertainty relevant for risk assessment and provide an overview of a range of population models. While all of the models reviewed have some utility in ecology, some have more comprehensive treatments of uncertainty than others. We identify the models that allow probabilistic assessments and sensitivity analyses, and we offer recommendations for further developments that aim towards more comprehensive and reliable ecological risk assessments for populations. 相似文献
134.
Öznur Ergen Akçin 《Biologia》2007,62(6):684-689
Morphological and micromorphological characters of the nutlets of ten Onosma species in Turkey were reported. Studied fruit surfaces show some variations. Based on the structure and patterns of epidermis
cells of the nutlets, two principal types can be distinguished. In Type 1, the epidermal cells of the nutlet surface are formed
in a reticulate pattern with varied sizes and shapes of the meshes. This type is the most common type in the studied species.
Seven of the species observed belong to the reticulate type, i.e. O. bracteosum, O. mutabile, O. aleppicum, O. bornmuelleri, O. aucheranum, O. araraticum and O. tauricum. In Type 2, the epidermal cells of the nutlet surface are formed in an elongated type with varied sizes and shapes. Three
of the observed species belong to this type, i.e. O. roussaei, O. isauricum and O. stenolobum. Significant taxonomic differences between species were determined on the surface of the nutlets. 相似文献
135.
Serbulent Yigit Ahmet Inanir Akın Tekcan Ercan Tural Gokhan Tuna Ozturk Gorkem Kismali Nevin Karakus 《Gene》2014
Objective
Interleukin-4 (IL-4) is a strong chondroprotective cytokine and polymorphisms within this gene may be a risk factor for osteoarthritis (OA). We aimed to investigate genotype and allele frequencies of IL-4 gene intron 3 variable number of tandem repeats (VNTR) polymorphism in patients with knee OA in a Turkish population.Methods
The study included 202 patients with knee OA and 180 healthy controls. Genomic DNA was isolated and IL-4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers followed by restriction fragment length polymorphism (RFLP) analysis.Results
Our result show that there was statistically significant difference between knee OA patients and control group with respect to IL-4 genotype distribution and allele frequencies (p = 0.000, OR: 0.20, 95% CI: 0.10–0.41, OR: 0.22, 95% CI: 0.12–0.42, respectively).Conclusions
Our findings suggest that there is an association of IL-4 gene intron 3 VNTR polymorphism with susceptibility of a person for development of knee OA. As a result, IL-4 gene intron 3 VNTR polymorphism could be a genetic marker in OA in a Turkish study population. This is the first association study that evaluates the associations between IL-4 gene VNTR polymorphism and knee OA. 相似文献136.
Dorina Rama-Esendagli Gunes Esendagli Guldal Yilmaz Dicle Guc 《Molecular biology reports》2014,41(5):2885-2892
Interactions with stromal components influence the growth, survival, spread, and colonization capacities of tumor cells. Fibroblasts and macrophages which are responsible for the stroma production and maintenance are of the basic elements found in tumor microenvironment. Cellular density and ratio of stromal cells to tumor cells can also have modulatory effects in cancer. Here, the contribution of fibroblast and/or macrophage cells on the malignant behavior of breast cancer cells was modeled in co-culture systems. Co-cultures were established at different cell densities and ratios with 4T1 breast cancer, NIH/3T3 or 3T3-L1 fibroblast, and J774A.1 monocyte/macrophage cell lines. Flow cytometry-based proliferation, 3D growth on alginate matrix, and matrigel invasion assays were performed to determine the change in the malignant assets of tumor cells. The data were also supported by immunocytochemical and morphological analyses. Co-culturing with fibroblasts (especially, NIH/3T3 cells) significantly supported the proliferation, scattering, and invasiveness of 4T1 cells whereas inclusion of macrophages disrupted this positive influence. On the other hand, the invasion capacity of 4T1 cells was not enhanced in the co-cultures with fibroblasts whose motility were inhibited with pertussis toxin pretreatment. Particularly at low-density seeding in 3D cultures, 4T1 cells could form substantially more spheroids than that of in the co-cultures with fibroblasts. Only, increasing the amount of fibroblasts could restore the 3D-growth. Intriguingly, co-existence of macrophage, fibroblast, and tumor cells in 3D cultures provided a convenient stroma sustaining the spheroid formation and growth. In conclusion, fibroblasts can form a favorable environment for tumor cells’ spread and motility whereas restricting their 3D-growth capacity. On the other hand, presence of macrophages may disrupt the influence of fibroblasts and enhance the spheroid formation by the tumor cells. 相似文献
137.
Timur Gültekin Başak Koca Özer Kazumichi Katayama Galip Akın 《International Journal of Anthropology》2006,21(3-4):231-239
Anthropometric estimation of midarm muscularity and fatness was employed as a general index of nutritional status in developing
countries. The present study attempts to evaluate the sex- and age-related pattern of regional muscle and fat area characteristics
in Turkish children. A cross-sectional study was carried out on 1,068 10- to 14-year-old children (583 boys and 485 girls)
from junior high schools in Ankara, the capital city of Turkey. According to general anthropometric protocols, weight, height,
triceps skinfold thickness, and midarm circumference measurements were taken and socioeconomic data were collected. Arm muscle
area (AMA) and arm fat area (AFA) were calculated and centile curves were evaluated using least median squares method. Results
showed significant sexual dimorphism in muscle and fat patterning. AFA was found to be higher among girls and AMA among boys.
The present findings suggest that the different levels of socioeconomic status (SES) appeared to be more prevalent on muscularity
among boys (p < 0.05) and adiposity among girls (p < 0.001). 相似文献
138.
Nontuberculous mycobacteria were identified from 45891 samples of 19553 patients with a prediagnosis of pulmonary tuberculosis between November 2004 and January 2009. Among 10041 (21.9%) culture positive samples, 208 (2.1%) pulmonary samples recovered from 77 individual patients were differentiated as mycobacteria other than tuberculosis (MOTT). Proportion of mycobacteria evaluated as causative agent for clinical infection were found as 0.16% (n = 31), mostly M. avium complex, M. abscessus and M. kansasii. Additionally, M. fortuitum-peregrinum complex, M. simiae, M. szulgai / intermedium and M. scrofulaceum were found as causative agent in 2, 2, 2 and 1 patient, respectively. Identification of infections caused by environmental or opportunistic pathogen mycobacteria is required in rapid and accurate diagnosis, infection control and treatment planning of infections caused by M. tuberculosis complex and/or MOTT. 相似文献
139.
140.
Elizabeth G. Pringle Erol Ak?ay Ted K. Raab Rodolfo Dirzo Deborah M. Gordon 《PLoS biology》2013,11(11)
Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant–plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners'' investments in a widespread ant–plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism. 相似文献