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排序方式: 共有1193条查询结果,搜索用时 15 毫秒
31.
Sophie J. Nightingale Hany Farid 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(8)
Artificial intelligence (AI)–synthesized text, audio, image, and video are being weaponized for the purposes of nonconsensual intimate imagery, financial fraud, and disinformation campaigns. Our evaluation of the photorealism of AI-synthesized faces indicates that synthesis engines have passed through the uncanny valley and are capable of creating faces that are indistinguishable—and more trustworthy—than real faces. 相似文献
32.
Background: In ordinary circumstances, objective structured clinical examination (OSCE) is a resource-intensive assessment method. In case of developing and implementing multidisciplinary OSCE, there is no doubt that the cost will be greater.Aim: Through this study a research project was conducted to develop, implement and evaluate a multidisciplinary OSCE model within limited resources.Methods: This research project went through the steps of blueprinting, station writing, resources reallocation, implementation and finally evaluation.Results: The developed model was implemented in the Primary Health Care (PHC) program which is one of the pillars of the Community-Based undergraduate curriculum of the Faculty of Medicine, Suez Canal University (FOM-SCU). Data for evaluation of the implemented OSCE model were derived from two resources. First, feedback of the students and assessors through self-administered questionnaires was obtained. Second, evaluation of the OSCE psychometrics was done. The deliverables of this research project included a set of validated integrated multi-disciplinary and low cost OSCE stations with an estimated reliability index of 0.6.Conclusion: After having this experience, we have a critical mass of faculty members trained on blueprinting and station writing and a group of trained assessors, facilitators and role players. Also there is a state of awareness among students on how to proceed in this type of OSCE which renders future implementation more feasible. 相似文献
33.
Janet T. Lin Sarah Kirst Stevan Cuci Alexandra Klem Yi-Min She Andrew M. Kropinski Hany Anany 《Viruses》2022,14(11)
Shiga toxin-producing Escherichia coli (STEC) is one of the leading causes of foodborne illnesses in North America and can lead to severe symptoms, with increased fatality risk for young children. While E. coli O157:H7 remains the dominant STEC serotype associated with foodborne outbreaks, there has been an increasing number of non-O157 STEC outbreaks in recent years. For the food industry, lytic bacteriophages offer an organic, self-limiting alternative to pathogen reduction—one that could replace or reduce the use of chemical and physical food processing methods. From EHEC-enriched sewage, we isolated a novel bacteriophage, vB_EcoM-4HA13 (4HA13). Phenotypic characterizations revealed 4HA13 to possess a myoviral morphotype, with a high specificity to non-motile O111 serotype, and a long latent period (90 min). Through genomic analyses, this 52,401-bp dsDNA phage was found to contain 81 CDS, but no detectable presence of antibiotic resistance, integrase, or virulence genes. A BLASTn search for each of the identified 81 CDS yielded homologues with low levels of similarity. Comparison of RNA polymerase and terminase large subunit amino acid sequences led to the proposal and acceptance of a new bacteriophage family, Chaseviridae, with 4HA13 representing a new species and genus. The discovery of this phage has broadened our current knowledge of bacteriophage diversity. 相似文献
34.
Ferdous A Eunus Ali M Alam S Hossain T Hany U Dissing J Akhteruzzaman S 《Legal medicine (Tokyo, Japan)》2006,8(5):297-299
Allele frequencies of 10 autosomal short tandem repeat (STR) loci, D3S1358, vWA, D16S539, D2S1338, D8S1179, D21S11, D18S51, D19S433, TH01 and FGA were determined in 211 unrelated Bangladeshi individual using AmpFLSTR SGM Plus PCR Amplification Kit. Statistical parameters of forensic importance, the power of discrimination (PD), observed and expected heterozygosity values (H), polymorphism information content (PIC), probability of match (PM), power of exclusion (PE) and typical paternity index (TPI) were calculated for the loci. These parameters indicated the usefulness of the loci in paternity testing and personal identification in the Bangladeshi population. 相似文献
35.
Objective and subjective comparison of standard 2-D and fully 3-D reconstructed data on a PET/CT system 总被引:1,自引:0,他引:1
Strobel K Rüdy M Treyer V Veit-Haibach P Burger C Hany TF 《Nuclear medicine communications》2007,28(7):555-559
OBJECTIVE: The relative advantage of fully 3-D versus 2-D mode for whole-body imaging is currently the focus of considerable expert debate. The nature of 3-D PET acquisition for FDG PET/CT theoretically allows a shorter scan time and improved efficiency of FDG use than in the standard 2-D acquisition. We therefore objectively and subjectively compared standard 2-D and fully 3-D reconstructed data for FDG PET/CT on a research PET/CT system. MATERIALS AND METHODS: In a total of 36 patients (mean 58.9 years, range 17.3-78.9 years; 21 male, 15 female) referred for known or suspected malignancy, FDG PET/CT was performed using a research PET/CT system with advanced detector technology with improved sensitivity and spatial resolution. After 45 min uptake, a low-dose CT (40 mAs) from head to thigh was performed followed by 2-D PET (emission 3 min per field) and 3-D PET (emission 1.5 min per field) with both seven slices overlap to cover the identical anatomical region. Acquisition time was therefore 50% less (seven fields; 21 min vs. 10.5 min). PET data was acquired in a randomized fashion, so in 50% of the cases 2-D data was acquired first. CT data was used for attenuation correction. 2-D (OSEM) and 3-D PET images were iteratively reconstructed. Subjective analysis of 2-D and 3-D images was performed by two readers in a blinded, randomized fashion evaluating the following criteria: sharpness of organs (liver, chest wall/lung), overall image quality and detectability and dignity of each identified lesion. Objective analysis of PET data was investigated measuring maximum standard uptake value with lean body mass (SUV(max,LBM)) of identified lesions. RESULTS: On average, per patient, the SUV(max) was 7.86 (SD 7.79) for 2-D and 6.96 (SD 5.19) for 3-D. On a lesion basis, the average SUV(max) was 7.65 (SD 7.79) for 2-D and 6.75 (SD 5.89) for 3-D. The absolute difference on a paired t-test of SUV 3-D-2-D based on each measured lesion was significant with an average of -0.956 (P=0.002) and an average of -0.884 on a patient base (P<0.05). With 3-D the SUV(max) decreased by an average of 5.2% for each lesion, and an average of 6.0% for each patient. Subjective analysis showed fair inter-observer agreement regarding detectability (kappa=0.24 for 3-D; 0.36 for 3-D) and dignity (kappa=0.44 for 3-D and 0.4 for 2-D) of the lesions. There was no significant diagnostic difference between 3-D and 2-D. Only in one patient, a satellite liver metastasis of a colon cancer was missed in 3-D and detected only in 2-D. On average, the overall image quality for 3-D images was equal (in 24%) or inferior (in 76%) compared to 2-D. CONCLUSION: A possible major advantage of 3-D data acquisition is the faster patient throughput with a 50% reduction in scan time. The fully 3-D reconstruction technique has overcome the technical drawbacks of current 3-D imaging technique. In our limited number of patients there was no significant diagnostic difference between 2-D and fully 3-D. 相似文献
36.
Mongiat-Artus P Miquel C Fléjou JF Coulet F Verine J Buhard O Soliman H Teillac P Praz F 《Virchows Archiv : an international journal of pathology》2006,449(2):238-243
Hereditary nonpolyposis colon cancer (HNPCC) syndrome is the most frequent hereditary cancer syndrome predisposing to cancers of various locations, especially colon, endometrium, stomach, and upper urinary tract. Carcinomas of the kidney parenchyma are not considered as an HNPCC-related tumor. HNPCC tumors are characterized by microsatellite instability (MSI) due to a defect in mismatch repair (MMR) and carry somatic frameshift mutations in mononucleotide repeats within the coding regions of key genes. We report the first case of a papillary carcinoma of the kidney in an HNPCC patient who developed carcinomas of the upper urinary tract, endocervix, and colon. Whereas the HNPCC-related tumors demonstrated MSI phenotype, loss of MSH2 protein expression, and frameshift mutations in several of the 13 target genes analyzed, the kidney cancer displayed MSS phenotype, normal MMR protein expression, and no frameshift mutation in target genes. Our observations do not support the possibility that papillary carcinomas are part of HNPCC syndrome. 相似文献
37.
The higher intergenotypic polymorphism of the surface antigen genes 5 (SAG5)A, SAG5C, and SAG5E in Toxoplasma gondii was proposed to be the outcome of positive selection pressure favoring variation within these loci. However, the exact nature
and magnitude of this selection is not completely known. To address this issue, the amino acids on which natural selection
may operate were identified by comparing the ratios of nonsynonymous and synonymous substitutions (p
N/
p
S) of homologous DNA sequences in strains belonging to the three major genotypes of T. gondii. Both positive and negative selections were detected and are likely to have contributed to shaping the patterns of nucleotide
substitution and polymorphism in SAG5 genes. Several sites identified in SAG5 loci as likely to be under positive selection suggesting that diversifying selection may have promoted divergence in these
genes. Also, it was noted that the SAG5 genetic loci contain many areas that exhibit signs of purifying selection; some of these areas might be the attractive candidates
for drug targets. Phylogenetic analysis using the neighbor-joining and maximum parsimony methods grouped the SAG5 sequences of T. gondii strains into three distinct statistically well-supported evolutionary lineages. These findings carry important implications
for human and veterinary toxoplasmosis epidemiology and may provide important insights into the pathways through which virulence
has evolved in T. gondii. 相似文献
38.
Elsheikha HM Murphy AJ Fitzgerald SD Mansfield LS Massey JP Saeed MA 《Parasitology research》2003,90(2):104-109
This report describes a new, inexpensive procedure for the rapid and efficient purification of Sarcocystis neurona sporocysts from opossum small intestine. S. neurona sporocysts were purified using a discontinuous potassium bromide density gradient. The procedure provides a source of sporocyst wall and sporozoites required for reliable biochemical characterization and for immunological studies directed at characterizing antigens responsible for immunological responses by the host. The examined isolates were identified as S. neurona using random amplified polymorphic DNA primers and restriction endonuclease digestion assays. This method allows the collection of large numbers of highly purified S. neurona sporocysts without loss of sporocyst viability as indicated by propidium iodide permeability and cell culture infectivity assays. In addition, this technique might also be used for sporocyst purification of other Sarcocystis spp. 相似文献
39.
Sandy Fulkerson Schaeffer Hany Aly 《The journal of maternal-fetal & neonatal medicine》2019,32(5):798-803
Background: Pregnancy with intrauterine device in place is rare and there are limited data that exist regarding associated perinatal outcomes.Objective: The objective of this study is to determine the association between presence of an intrauterine device during pregnancy and spontaneous abortion, induced abortion, and preterm or small for gestational age delivery outcomes.Study design: The National Inpatient Sample database was analyzed for the years 2010 and 2011. Maternal records with an intrauterine device in situ during delivery were identified using International Classification of Diseases, Ninth Revision, diagnostic codes. Primary outcome was incidence of spontaneous abortion. Secondary outcomes were incidence of induced abortion, preterm delivery, and small for gestational age. Data were analyzed using Chi-square and Fisher’s exact tests to calculate odds ratios (ORs) of abortion in association with intrauterine device in situ during pregnancy. Maternal birth records were further analyzed for adverse neonatal outcomes using logistic regression models, controlling for possible confounding variables.Results: The data included 8,597,284 maternal birth records; 0.02% with an intrauterine device in situ. Patients with an intrauterine device in situ experienced a higher frequency of the pregnancy ending in spontaneous abortion (OR: 7.15; 95% confidence interval (CI): 5.06–10.09; p?.001) and induced abortion (OR: 23.12; 95% CI: 15.55–34.36; p?.001) than patients without an intrauterine device in place. Adjusted odds ratio for preterm delivery among women with an intrauterine device in situ was 2.04 (95% CI: 1.71–2.43; p?.001) compared with women without an intrauterine device, and adjusted odds ratio for delivery of a small for gestational age infant among intrauterine device cohort was 0.56 (95% CI: 0.34–0.92; p?=?.022), after controlling for associated demographic and clinical variables.Conclusion: The presence of an intrauterine device in situ during pregnancy was associated with increased spontaneous and induced abortions, and increased incidence of delivery of a preterm, but not small for gestational age infant. 相似文献
40.
Hany Balamoun Robina Mohammad Ayman Hamade 《Annals of the Royal College of Surgeons of England》2010,92(7):e3-e5
Intestinal obstruction is a common surgical emergency. It is often due to adhesions; however, when the patient is young and has a virgin abdomen, we have to consider uncommon causes. We present a rare case of reversed rotation of the midgut as a cause for intestinal obstruction. 相似文献