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排序方式: 共有679条查询结果,搜索用时 15 毫秒
81.
Jalil Abshenas Amin Derakhshanfar Mohammad Hosein Ferdosi Saeid Hasanzadeh 《Comparative clinical pathology》2012,21(6):1243-1248
Acetaminophen overdose causes severe hepatotoxicity leading to liver failure in experimental animals and humans. This study was undertaken to evaluate the protective effect of kombucha tea (KT) against acetaminophen-induced hepatotoxicity. Forty male Balb/c mice were divided into four equal groups: (1) the control group, (2) KT-treated group, (3) acetaminophen-treated group, and (4) KT/acetaminophen-treated group. All mice in group 4 were given KT orally for 7?days before a single hepatotoxic dose of acetaminophen (1,000?mg/kg orally). Activities of liver marker enzymes in serum; aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP); and total protein (TP), albumin (ALB), and direct and total bilirubin levels were determined. Acetaminophen challenge caused significant increases in the levels of bilirubin and liver enzymes (AST, ALT, ALP, and LDH), while TP and ALB levels were reduced significantly. Histopathologic assessments showed that severe glycogen storage in hepatocytes, hepatocellular degeneration and necrosis, mononuclear cell infiltration in portal area, dilation of central veins, and capillarization also reduced in KT/acetaminophen group compared to acetaminophen-treated mice. In conclusion, these findings suggest that KT has protective effect on acetaminophen-induced hepatotoxicity. 相似文献
82.
Saeid R. Nourollahi Fard Nima Ghalekhani Reza Kheirandish Saeid Fathi Ehsan Norouzi Asl 《Asian Pacific Journal of Tropical Biomedicine》2012,2(11):885-888
Objective
To evaluate the prevalence of nymphal stages of L. serrata in mesenteric lymph nodes of camels slaughtered in Mashhad slaughterhouse, Northeast of Iran.Methods
For this purpose, mesenteric lymph nodes of 400 camels of different sex and age were examined. The lymph nodes were examined macroscopically and a digestion method was also applied for investigation of samples which was negative macroscopically.Results
The mesenteric lymph nodes of 73 camels out of 400 (18.25%) were infected by L. serrata nymphs.Conclusions
Prevalence of L. serrata nymphs in males and females and different age was not significantly different (P>0.05), but difference was observed between the prevalence in different seasons (P< 0.05). The potential importance of these findings to human health is discussed. This is the first report of infection with L. serrate of camels in camels slaughtered at northeast of Iran. 相似文献83.
Shiga toxin (Stx) is the principal virulence factor of Shigatoxigenic Escherichia coli (STEC), a food-born pathogen associated disease with uncomplicated diarrhea or the hemolytic-uremic syndrome. In this study, rabbit polyclonal anti recombinant A, B subunits of Shiga toxin and holotoxin antisera were raised and employed for immunological purpose. By immunoblotting, these antisera recognized respective subunit and the holotoxin antiserum recognized both subunits, equally. The raised antisera could also neutralize the cytotoxicity of the shiga toxin on vero cells. The neutralizing ability of the prepared sera was compared for different subunits. The neutralization of toxicity was observed by incubation of raised sera with the rStx or Shiga toxin from wild type strains. The inhibition of cell toxicity was shown by anti-A, anit-B and anti-AB antisera, separately. It was shown that anti-A antibody, more significantly recognized Stx producing strains, comparing to anti-B antibody. These sera from immunized rabbits were also used as specific antibodies in Enzyme-Linked Immunosorbant Assay (ELISA) for detection of Shiga toxin. It was demonstrated that the raised antibodies especially antibody against A subunit could be a useful tool for immunological diagnosis of STEC induced infection. 相似文献
84.
85.
Esmaeilzadeh Maryam; Parsaee Mozhgan; Peighambari Mohammad Mehdi; Sadeghpour Anita; Khamooshi Amir J.; Hosseini S. Saeid; Mozaffari Kambiz 《European journal of echocardiography》2009,10(1):165-167
The most common fungal organism to cause endocarditis is Candidawhich is followed by Aspergillus. Aspergillus endocarditis canoccur in either the native or prosthetic heart valves, usuallyoccurs post-operative after cardiac valve surgery. This caseis illustrative of a 49-year-old man with previous history ofcoronary artery bypass grafting presenting with aortic valveendocarditis which was diagnosed as Aspergillus endocarditis.Unfortunately, despite medical and surgical therapy, progressivefatal aortic invasion occurred. 相似文献
86.
OBJECTIVE: To identify all published studies evaluating computerized physician order entry (CPOE) in the inpatient setting and uniformly classify these studies on outcome measure and study design. DATA SOURCES: All studies that evaluated the effect of CPOE on outcomes pertaining to the medication process in inpatients were electronically searched in MEDLINE (1966 to August 2006), EMBASE (1980 to August 2006) and the Cochrane library. In addition, the bibliographies of retrieved articles were manually searched. Articles were selected if one of their main objectives was CPOE evaluation in an inpatient setting. REVIEW METHOD: Identified titles and abstracts were independently screened by three reviewers to determine eligibility for further review. RESULTS: We found 67 articles, which included articles on CPOE evaluation on some outcome at the time of ordering. Most papers evaluated multiple outcome measures. The outcome measures were clustered in the following categories: adherence (n=22); alerts and appropriateness of alerts (n=7); safety (n=21); time (n=7); costs and (organizational) efficiency (n=23); and satisfaction, usage and usability (n=10). Most studies used a before-after design (n=35) followed by observational studies (n=24) and randomized controlled trials (n=8). CONCLUSION: The impact of CPOE systems was especially positive in the category adherence to guidelines, but also to some extent in alerts and appropriateness of alerts; costs and organizational efficiency; and satisfaction and usability. Although on average, there seems to be a positive effect of CPOE on safety, studies tended to be non-randomized and were focused on medication error rates, not powered to detect a difference in adverse drug event rates. Some recent studies suggested that errors, adverse drug events (ADEs) and even mortality increased after CPOE implementation. Only in the category time the impact has been shown to be negative, but this only refers to the physician's time, not the net time. Except for safety, on the whole spectrum of outcomes, results of RCT studies were in line with non-RCT study results. 相似文献
87.
Oloomi M Bouzari S 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2008,116(2):125-132
Cytolethal distending toxin (CDT)-producing Escherichia coli strains are considered to be a heterogeneous group of E. coli. In the present investigation, 20 CDT-producing E. coli strains, which had already been shown to be cytotoxic necrotizing factor (cnf) gene positive, were selected by PCR. Since these strains proved to be CDT producers on CHO cells but were partially characterized by PCR, they were subjected to PCR analysis to amplify the complete coding region of cdt genes. Moreover, the genetic relatedness of these strains was examined by pulse field gel electrophoresis (PFGE). To check the extent of homogeneity of these strains at the chromosomal level, tRNA insertion site analysis was performed. The CDT-producing E. coli strains under investigation were shown to be heterogeneous and diverse in regard to their genetic analysis. This observed diversity could be an independent acquisition of virulence genes that might occur through horizontal gene transfer by mobile genetic elements. This conclusion is based on the fact that data shown by tRNA insertion site analysis revealed that there is no common pattern of insertion among these isolates although they do share a common trait of CDT production. 相似文献
88.
Design of an inhalable dry powder formulation of DOTAP-modified PLGA nanoparticles loaded with siRNA
Ditte Krohn JensenLinda Boye Jensen Saeid Koocheki Lasse BengtsonDongmei Cun Hanne Mørck NielsenCamilla Foged 《Journal of controlled release》2012,157(1):141-148
Matrix systems based on biocompatible and biodegradable polymers like the United States Food and Drug Administration (FDA)-approved polymer poly(DL-lactide-co-glycolide acid) (PLGA) are promising for the delivery of small interfering RNA (siRNA) due to favorable safety profiles, sustained release properties and improved colloidal stability, as compared to polyplexes. The purpose of this study was to design a dry powder formulation based on cationic lipid-modified PLGA nanoparticles intended for treatment of severe lung diseases by pulmonary delivery of siRNA. The cationic lipid dioleoyltrimethylammoniumpropane (DOTAP) was incorporated into the PLGA matrix to potentiate the gene silencing efficiency. The gene knock-down level in vitro was positively correlated to the weight ratio of DOTAP in the particles, and 73% silencing was achieved in the presence of 10% (v/v) serum at 25% (w/w) DOTAP. Optimal properties were found for nanoparticles modified with 15% (w/w) DOTAP, which reduced the gene expression with 54%. This formulation was spray-dried with mannitol into nanocomposite microparticles of an aerodynamic size appropriate for lung deposition. The spray-drying process did not affect the physicochemical properties of the readily re-dispersible nanoparticles, and most importantly, the in vitro gene silencing activity was preserved during spray-drying. The siRNA content in the powder was similar to the theoretical loading and the siRNA was intact, suggesting that the siRNA is preserved during the spray-drying process. Finally, X-ray powder diffraction analysis demonstrated that mannitol remained in a crystalline state upon spray-drying with PLGA nanoparticles suggesting that the sugar excipient might exert its stabilizing effect by sterical inhibition of the interactions between adjacent nanoparticles. This study demonstrates that spray-drying is an excellent technique for engineering dry powder formulations of siRNA nanoparticles, which might enable the local delivery of biologically active siRNA directly to the lung tissue. 相似文献
89.
Hashemi M Bahari A Hashemzehi N Moazeni-Roodi A Shafieipour S Bakhshipour A Ghavami S 《Pathophysiology》2012,19(2):115-119
BackgroundThe aim of the study was to investigate paraoxonase-1 (PON1) and aryl esterase (ARE) activities in patients with nonalcoholic fatty liver disease (NAFLD).Materials and methodsThis case–control study was done on 83 subjects with confirmed NAFLD (50 male, 33 female, age; 40.46 ± 12.13 years) and 138 healthy individuals (75 male, 63 female; age; 40.94 ± 14.50 years). PON1, salt-stimulated PON1 and ARE activities were determined using paraoxon and phenyl acetate as substrate, respectively.ResultsThe levels of PON1 activities in NAFLD and healthy individuals were 90.83 ± 63.65 IU/L and 79.41 ± 68.14 IU/L, respectively. There was no significant differences regarding PON1 activity between NAFLD and healthy subjects (p = 0.229). While, ARE activity was significantly higher in NAFLD (83.34 ± 28.36 KU/L) than in normal subjects (64.06 ± 27.49 KU/L) (p < 0.001).ConclusionsOur results showed that PON1 activity is not a promising biomarker for the evaluation of NAFLD while arylesterase may have, but further studies in larger samples with different ethnic groups are required to validate our findings. 相似文献
90.