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31.
32.
The sensitivity and accuracy of molecular diagnosis of Salmonella from meat and poultry products using polymerase chain reaction (PCR) was compared with conventional microbiological methods. A total of 212 samples representing the most frequently used fresh and frozen meat and poultry products (whole, cut, ground, and processed) were collected from different locations within the city of Irbid. DNA was extracted directly from each food sample and amplified using Salmonella-specific primers. Samples were also analysed using conventional microbiological methods for the presence of Salmonella spp. Results showed that Salmonella was detected in 185 samples out of 212 (87%) by PCR technique, while 172 (81%) samples were detected Salmonella positive by conventional microbiological methods. On the other hand, 27 (12.7%) samples were negative by PCR and 40 (18.8%) samples were negative by conventional microbiological methods. PCR assay proved to be an effective method for Salmonella detection in meat and poultry products with high specificity and sensitivity and more importantly a less time-consuming procedure. Using PCR, Salmonella spp. detection could be achieved within 24–36 h compared to 3–8 days for the conventional microbiological methods. 相似文献
33.
Yong-Hong Kuo Omar Rado Benedetta Lupia Janny M. Y. Leung Colin A. Graham 《Flexible Services and Manufacturing Journal》2016,28(1-2):120-147
This paper presents a case study which uses simulation to analyze patient flows in a hospital emergency department in Hong Kong. We first analyze the impact of the enhancements made to the system after the relocation of the Emergency Department. After that, we developed a simulation model (using ARENA) to capture all the key relevant processes of the department. When developing the simulation model, we faced the challenge that the data kept by the Emergency Department were incomplete so that the service-time distributions were not directly obtainable. We propose a simulation–optimization approach (integrating simulation with meta-heuristics) to obtain a good set of estimate of input parameters of our simulation model. Using the simulation model, we evaluated the impact of possible changes to the system by running different scenarios. This provides a tool for the operations manager in the Emergency Department to “foresee” the impact on the daily operations when making possible changes (such as, adjusting staffing levels or shift times), and consequently make much better decisions. 相似文献
34.
Developing core outcome set for vitiligo clinical trials: international e‐Delphi consensus 下载免费PDF全文
Viktoria Eleftheriadou Kim Thomas Nanja van Geel Iltefat Hamzavi Henry Lim Tamio Suzuki Ichiro Katayama Tag Anbar Marwa Abdallah Laïla Benzekri Yvon Gauthier John Harris Caio Cesar Silva de Castro Amit Pandya Boon Kee Goh Cheng‐Che E. Lan Naoki Oiso Ahmed Al Issa Samia Esmat Caroline Le Poole Ai‐Young Lee Davinder Parsad Alain Taieb Mauro Picardo Khaled Ezzedine 《Pigment cell & melanoma research》2015,28(3):363-369
35.
Omar M. Khdour Indrajit Bandyopadhyay Sandipan Roy Chowdhury Nishant P. Visavadiya Sidney M. Hecht 《Bioorganic & medicinal chemistry》2018,26(12):3359-3369
Friedreich’s ataxia (FRDA) is an autosomal recessive neurodegenerative disorder resulting from reduced expression of the protein frataxin (FXN). Although its function is not fully understood, frataxin appears to help assemble iron sulfur clusters; these are critical for the function of many proteins, including those needed for mitochondrial energy production. Finding ways to increase FXN levels has been a major therapeutic strategy for this disease. Previously, we described a novel series of methylene violet analogues and their structural optimization as potential therapeutic agents for neurodegenerative and mitochondrial disorders. Presently, a series of methylene blue analogues has been synthesized and characterized for their in vitro biochemical and biological properties in cultured Friedreich’s ataxia lymphocytes. Favorable methylene blue analogues were shown to increase frataxin levels and mitochondrial biogenesis, and to improve aconitase activity. The analogues were found to be good ROS scavengers, and able to protect cultured FRDA lymphocytes from oxidative stress resulting from inhibition of complex I and from glutathione depletion. The analogues also preserved mitochondrial membrane potential and augmented ATP production. Our results suggest that analogue 5, emerging from the initial structure of the parent compound methylene blue (MB), represents a promising lead structure and lacks the cytotoxicity associated with the parent compound MB. 相似文献
36.
Simms TM Wright MR Hernandez M Perez OA Ramirez EC Martinez E Herrera RJ 《American journal of physical anthropology》2012,148(4):618-631
Although previous studies have characterized the genetic structure of populations from Haiti and Jamaica using classical and autosomal STR polymorphisms, the patrilineal influences that are present in these countries have yet to be explored. To address this lacuna, the current study aims to investigate, for the first time, the potential impact of different ancestral sources, unique colonial histories, and distinct family structures on the paternal profile of both groups. According to previous reports examining populations from the Americas, island-specific demographic histories can greatly impact population structure, including various patterns of sex-biased gene flow. Also, given the contrasting autosomal profiles provided in our earlier study (Simms et al.: Am J Phys Anthropol 142 (2010) 49-66), we hypothesize that the degree and directionality of gene flow from Europeans, Africans, Amerindians, and East Asians are dissimilar in the two countries. To test this premise, 177 high-resolution Y-chromosome binary markers and 17 Y-STR loci were typed in Haiti (n = 123) and Jamaica (n = 159) and subsequently utilized for phylogenetic comparisons to available reference collections encompassing Africa, Europe, Asia (East and South), and the New World. Our results reveal that both studied populations exhibit a predominantly South-Saharan paternal component, with haplogroups A1b-V152, A3-M32, B2-M182, E1a-M33, E1b1a-M2, E2b-M98, and R1b2-V88 comprising 77.2% and 66.7% of the Haitian and Jamaican paternal gene pools, respectively. Yet, European derived chromosomes (i.e., haplogroups G2a*-P15, I-M258, R1b1b-M269, and T-M184) were detected at commensurate levels in Haiti (20.3%) and Jamaica (18.9%), whereas Y-haplogroups indicative of Chinese [O-M175 (3.8%)] and Indian [H-M69 (0.6%) and L-M20 (0.6%)] ancestry were restricted to Jamaica. 相似文献
37.
Eighty‐two isolates of Rhizoctonia solani were recorded from roots of naturally‐infected seedlings of the Egyptian cotton (Gossypium barbadense L.). Anastomosis groups (AGs) of the isolates were determined by using 13 different AGs testers. Three (3.7%) of the isolates were identified as R. solani AG7, while the remaining isolates were belonging to the AG 2‐1, AG4 and AG5. The identification of the three isolates was based on the frequency of the C2 reaction with the AG7 tester isolate. No fusion was observed between AG7 and isolates representing the other 13 AGs. Colonies of AG7 isolates grown on potato dextrose agar (PDA), malt yeast agar (MYA) and melt peptone agar (MPA) were brown to dark brown with aerial mycelium and sclerotia. The isolates had pitted sclerotial clusters and brownish exudates after 21 days of culturing on PDA, but without clear zonation. Pathogenicity test under greenhouse conditions revealed that AG7 caused the common symptoms of damping–off, which included seed rot, lesions on the hypocotyls and root rot. 相似文献
38.
Eloualid A Rhaissi H Reguig A Bounaceur S El Houate B Abidi O Charif M Louanjli N Chadli E Barakat A Bashamboo A McElreavey K Rouba H 《PloS one》2012,7(4):e34902
Infertility affects around 1 in 10 men and in most cases the cause is unknown. The Y chromosome plays an important role in spermatogenesis and specific deletions of this chromosome, the AZF deletions, are associated with spermatogenic failure. Recently partial AZF deletions have been described but their association with spermatogenic failure is unclear. Here we screened a total of 339 men with idiopathic spermatogenic failure, and 256 normozoospermic ancestry-matched men for chromosome microdeletions including AZFa, AZFb, AZFc, and the AZFc partial deletions (gr/gr, b1/b3 and b2/b3).AZFa and AZFc deletions were identified in men with severe spermatogenic failure at similar frequencies to those reported elsewhere. Gr/gr deletions were identified in case and control populations at 5.83% and 6.25% respectively suggesting that these deletions are not associated with spermatogenic failure. However, b2/b3 deletions were detected only in men with spermatogenic failure and not in the normospermic individuals. Combined with our previous data this shows an association of the b2/b3 deletion (p = 0.0318) with spermatogenic failure in some populations. We recommend screening for this deletion in men with unexplained spermatogenic failure. 相似文献
39.
Aaron S. Karat Tanvier Omar Anne von Gottberg Mpho Tlali Violet N. Chihota Gavin J. Churchyard Katherine L. Fielding Suzanne Johnson Neil A. Martinson Kerrigan McCarthy Nicole Wolter Emily B. Wong Salome Charalambous Alison D. Grant 《PloS one》2016,11(11)
BackgroundEarly mortality among HIV-positive adults starting antiretroviral therapy (ART) remains high in resource-limited settings, with tuberculosis (TB) the leading cause of death. However, current methods to estimate TB-related deaths are inadequate and most autopsy studies do not adequately represent those attending primary health clinics (PHCs). This study aimed to determine the autopsy prevalence of TB and other infections in adults enrolled at South African PHCs in the context of a pragmatic trial of empiric TB treatment (“TB Fast Track”).ConclusionsTB, followed by bacterial infections, were the leading findings at autopsy among adults with advanced HIV enrolled from primary care clinics. To reduce mortality, strategies are needed to identify and direct those at highest risk into a structured pathway that includes expedited investigation and/or treatment of TB and other infections. 相似文献
40.