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排序方式: 共有759条查询结果,搜索用时 15 毫秒
1.
Dra/AfaE adhesin of uropathogenic Dr/Afa+ Escherichia coli mediates mortality in pregnant rats 总被引:1,自引:0,他引:1 下载免费PDF全文
Wroblewska-Seniuk K Selvarangan R Hart A Pladzyk R Goluszko P Jafari A du Merle L Nowicki S Yallampalli C Le Bouguénec C Nowicki B 《Infection and immunity》2005,73(11):7597-7601
Escherichia coli bearing adhesins of the Dr/Afa family frequently causes urogenital infections during pregnancy in humans and has been associated with mortality in pregnant rats. Two components of the adhesin, Dra/AfaE and Dra/AfaD, considered virulence factors, are responsible for bacterial binding and internalization. We hypothesize that gestational mortality caused by Dr/Afa+ E. coli is mediated by one of these two proteins, Dra/AfaE or Dra/AfaD. In this study, using afaE and/or afaD mutants, we investigated the role of the afaE and afaD genes in the mortality of pregnant rats from intrauterine infection. Sprague-Dawley rats, on the 17th day of pregnancy, were infected with the E. coli afaE+ afaD and afaE afaD+ mutants. The clinical E. coli strain (afaE+ afaD+) and the afaE afaD double mutant were used as positive and negative controls, respectively. The mortality rate was evaluated 24 h after infection. The highest maternal mortality was observed in the group infected with the afaE+ afaD+ strain, followed by the group infected with the afaE+ afaD strain. The mortality was dose dependent. The afaE afaD double mutant did not cause maternal mortality, even with the highest infection dose. The in vivo studies corresponded with the invasion assay, where the afaE+ strains were the most invasive (afaE+ afaD strain > afaE+ afaD+ strain), while the afaE mutant strains (afaE afaD+ and afaE afaD strains) seemed to be noninvasive. This study shows for the first time that the afaE gene coding for the AfaE subunit of Dr/Afa adhesin is involved in the lethal outcome of gestational infection in rats. This lethal effect associated with AfaE correlates with the invasiveness of afaE+ E. coli strains in vitro. 相似文献
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Farhad Ahmadi Batool Jafari Mehdi Rahimi-Nasrabadi Sahar Ghasemi Kumars Ghanbari 《Toxicology in vitro》2013,27(2):641-650
In this work we proposed a model for in vitro interaction of fenitrothion (FEN) with calf thymus-DNA by combination of multispectroscopic and two dimensional molecular modeling (ONIOM) methods. The circular dichroism results showed that FEN changes the conformation of B-DNA and caused some changes to C-DNA form. The FT-IR results confirmed a partial intercalation between FEN and edges of all base pairs. The competitive fluorescence, using methylene blue as fluorescence probe, in the presence of increasing amounts of FEN, revealed that FEN is able to release the non-intercalated methylene blue from the DNA. The weak chemical shift and peak broadening of 1H NMR spectrum of FEN in the presence of DNA confirmed a non-intercalation mode. The 31P NMR showed that FEN interacts more with DNA via its –NO2 moiety. The ONIOM, based on the hybridization of QM/MM (DFT, 6.31++G (d,p)/UFF) methodology, was also performed by Gaussian 2003 package. The results revealed that the interaction is base sequence dependent, and FEN interacts more with AT base sequences. 相似文献
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Zali MR Mehr AJ Rezaian M Meamar AR Vaziri S Mohraz M 《Japanese journal of infectious diseases》2004,57(6):268-270
Parasites are important enteric pathogens among patients with human immunodeficiency virus (HIV) infection. There have been very few reports on the prevalence of intestinal parasites among such patients in Iran. To determine the prevalence of intestinal parasites among HIV-positive individuals, we collected single stool samples and analyzed them for detection of various intestinal parasites from 206 HIV-positive individuals with different immune status visited in different medical centers in Iran. The data were tested for statistical significance with chi(2) and Mann-Whitney U tests. The overall prevalence of intestinal parasites was 18.4% (95%CI: 13.7, 24.3). More specifically, the following parasites were identified: Giardia lamblia (7.3%), Blastocystis hominis (4.4%), Entamoeba coli (3.9%), and Cryptosporidium parvum (1.5%). Other parasites observed included Strongyloides stercoralis and Hymenolepis nana in two cases and Dicrocoelium dendriticum in one. Of the 38 patients who tested positive for intestinal parasites, 15 (39.2%) had diarrhea. Intestinal parasites were significantly more common among patients with diarrhea than those without (P < 0.001). Further, CD4 counts were significantly lower among individuals with diarrhea than those without (P < 0.001). This study highlights the importance of testing for intestinal parasites among Iranian HIV-positive patients, especially those with low immunity presenting with diarrhea. 相似文献
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Mojtaba Jafari Hossein Rafiei Asra Nassehi Farzaneh Soleimani Mansuor Arab Mohammad Reza Noormohammadi 《Indian Journal of Palliative Care》2015,21(2):192-197
Background:
Education about caring for dying patients could be effective in changing nursing students’ attitude toward caring for dying patients.Aim:
The aim of the present study was to examine the nursing students’ attitude toward caring for dying patients and effects of education on their attitude.Materials and Methods:
The present study enjoys a quasi-experimental method with using one-group pre-test/post-test design conducted in Bam in southeast of Iran. The attitude of nursing students was measured using Frommelt Attitude Toward Care of the Dying (FATCOD) scale before and after an educational intervention. Data were analyzed using non-parametric tests in Statistical Package for the Social Sciences (SPSS) 18 software.Results:
Of 32 students, 30 participated in this study (response rate of 94%). Only 20% of the students reported previous experience of dying patients in their clinical courses. Students showed moderately negative to neutral attitudes toward caring for dying patients. Education has improved students’ attitude significantly (mean score of FATCOD before study were 3.5 ± 0.43 and after intervention were 4.7 ± 0.33) (P < 0.001).Conclusion:
Educational programs about death and caring for dying patients should be added to undergraduate nursing curricula. Further research recommended examining nursing students’ knowledge about caring for dying patients and the effect of education on their knowledge. 相似文献9.
Mostafa Jafari Thanh N. Nguyen Santiago Ortega-Gutierrez Muhammad Shazam Hussain Ameer E. Hassan Asad Ikram Javed Khader Eliyas Gustavo J. Rodriguez Afshin A. Divani 《Journal of stroke and cerebrovascular diseases》2021,30(3):105556
Objectives/BackgroundMedical therapy is the first line of treatment for intracranial atherosclerotic disease (ICAD). Percutaneous transluminal angioplasty and stenting (PTAS) are mainly considered for those patients with severe stenosis and recurrent events despite aggressive medical therapy. In this review, we discuss the application of PTAS as a treatment option for ICAD and its future prospect.Materials and MethodsWe did the literature review of the key articles and guidelines to elaborate on the role of PTAS in the management of ICAD based on the current data and expert opinion. We searched PubMed, Google Scholar, and Scopus up to August 2020, and included articles published only in the English language.ResultsSince the publication of the results from SAMMPRIS and VISSIT trials, stenting is no longer recommended for secondary stroke prevention in patients with symptomatic ICAD. However, recent clinical studies on intracranial stenting for a subgroup of ICAD patients have shown promising results, likely due to better patient selection and continued advancement of endovascular techniques.ConclusionThere exists a lack of consensus regarding the best endovascular treatment approach (e.g., angioplasty alone or balloon mounted stent vs. self-expanding stent with or without prior angioplasty) or management of in-stent restenosis. Another area of clinical controversy relates to the ideal use and duration of antiplatelet therapy. 相似文献
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