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21.
Resistance of Pseudomonas aeruginosa strains to the broad-spectrum cephalosporins may be mediated by the extended-spectrum β-lactamases (ESBLs). These enzymes are encoded by different genes located on either chromosomes or plasmids. This study aimed to investigate the prevalence of ESBLs and antimicrobial susceptibilities of P. aeruginosa isolated from burn patients in Tehran, Iran. Antimicrobial susceptibility of 170 isolates to cefpodoxime, aztreonam, ciprofloxacin, ofloxacin, ceftazidime, cefepime, imipenem, meropenem, cefotaxime, levofloxacin, piperacillin–tazobactam and ceftriaxone was determined by disc agar diffusion test. Polymerase chain reaction (PCR) amplification of the genes encoding OXA-10, PER-1 and VEB-1 was also performed. All isolates (100%) were resistant to ceftazidime, cefotaxime, cefepime and aztreonam. Imipenem and meropenem were the most effective anti-pseudomonal agents. The results revealed that 148 (87.05%) of the isolates were multidrug resistant and 67 (39.41%) of the isolates were ESBL positive. Fifty (74.62%), 33 (49.25%) and 21 (31.34%) strains among 67 ESBL-producing strains amplified blaOXA-10, blaPER-1 and blaVEB-1 respectively.  相似文献   
22.
This study examined the clinical validity of a Persian language version of the Automatic Thoughts Questionnaire (ATQ-Persian). We hypothesized that patients with major depression can be clearly distinguished from non-patient members of general population regarding both frequency of negative thoughts (ATQ-F) and degree of belief in these thoughts (ATQ-B). To test this hypothesis, we used discriminant function analysis in a group of 30 female patients with major depression and 30 female non-patient volunteers. ATQ-F and ATQ-B discriminated the large majority of depressed patients from non-patient volunteers and were correlated with the severity of depression as measured by scores on the Beck Depression Inventory-second edition. The data provide preliminary evidence for clinical validity and utility of ATQ-Persian.  相似文献   
23.
Objective:To explore the effect of ethyl acetate gum resin extract of Boswellia serrata on lipopolysaccharide(LPS)induced inflammation and oxidative damage in hepatic and renal tissues of rats.Methods:The rats were divided into four groups:control,LPS,LPS+Boswellia serrata extracts(100 mg/kg and 200 mg/kg).LPS(1 mg/kg)and the extract(100 and 200 mg/kg,30 min before LPS)were administered intraperitoneally for 3 weeks.The levels of liver enzymes,albumin,total protein,creatinine,blood urea nitrogen(BUN),interleukin(IL)-6,malondialdehyde(MDA),and total thiol groups and superoxide dismutase(SOD)and catalase(CAT)activities were measured.Results:The levels of liver enzymes,creatinine,and BUN,IL-6,MDA in the LPS group were markedly increased(P<0.001)while albumin,total protein,and total thiol concentration,as well as SOD and CAT activities,were decreased compared with the control group(P<0.05 or 0.01).Boswellia serrata extracts diminished the levels of liver enzymes,creatinine,BUN,IL-6,and MDA(P<0.01 and P<0.001),and elevated the concentration of total protein and total thiol and SOD and CAT activities(P<0.05 or 0.01).Conclusions:The ethyl acetate gum resin extract of Boswellia serrata reduces LPS-induced inflammatory reactions and oxidative damage,thus ameliorating hepatic and renal function.  相似文献   
24.
Polychlorinated biphenyls used previously in industry are widespread environmental contaminants under scrutiny for their possible reproductive effects in humans. In this study, 200 breast milk samples from eligible Victorian mothers were used for measuring maternal contamination and their possible effect on the offspring was investigated. No significant association was found between maternal PCB contamination and low birth weight, small for gestational age and previous miscarriage or stillbirth. The elevated odd ratios of prematurity, increased with increase in contamination level but were nonsignificant. Higher PCB contamination was not in favor of any gender in the offspring. Our results suggest that chronic, low contamination with PCBs does not pose a reproduction threat in humans.  相似文献   
25.

Aim

This ex-vivo study aimed to compare canal transportation in mesio-buccal canal of mandibular first molars prepared with Mtwo and Revo-S multi-file and Neoniti single-file nickel–titanium (Ni–Ti) rotary systems using cone-beam computed tomography (CBCT).

Methodology

CBCT scans were obtained from 60 extracted mandibular first molars and the teeth were randomly divided into three groups. Mesio-buccal canal of mesial root was prepared with Revo-S, Neoniti or Mtwo rotary systems according to the instructions of the manufacturers. Post-operative CBCT scans were also obtained. A single operator performed canal preparations while another operator blinded to the group allocation of teeth did the measurements. Data were analyzed using SPSS 20. The mean and standard deviation (SD) of the amount of canal transportation were calculated and compared between the groups using the Friedman test (P  0.05).

Results

No significant difference was noted in canal transportation among the groups in the middle and apical third (P > 0.05). The rotary single-file instrument caused significantly greater canal transportation in the coronal third.

Conclusion

No significant difference exists among different rotary systems in the amount of canal transportation caused in the middle and apical third of the mesio-buccal canal in mandibular first molars. Although all rotary files caused some degrees of canal transportation, the rotary single-file instrument caused significantly greater canal transportation than the multiple-file sequences in the coronal third.  相似文献   
26.
27.
Background and objective:   The prevalence of multidrug-resistant tuberculosis (MDR-TB) has increased substantially in the past 20 years, however, there are no data specific to Iran. This study investigated patients suspected to have MDR-TB, attending the TB referral hospital in Iran.
Methods:   All patients suspected of having MDR-TB on hospital admission in the period 2003–2005 were included in this study. Sputum from all patients was tested for smear and culture, and drug sensitivity testing was performed using the proportion method. Patients were categorized into three groups based on their history of medical treatment. Group I consisted of patients with CAT I regimen failure; Group II consisted of patients with a history of CAT II regimen failure and Group III comprised patients with a history of more than two courses of irregular CAT I anti-TB regimen.
Results:   There were 105 patients recruited; 32 in Group I, 53 in Group II and 20 in Group III. There were no significant differences between the three groups in their resistance to first-line anti-TB drugs. Fifty-five patients were diagnosed with MDR-TB. The prevalence of MDR-TB was 56% (18 cases) in group I, 49% (26 cases) in group II and 55% (11 cases) in group III. No significant difference in the pattern of drug resistance was observed between the three groups.
Conclusion:   The prevalence of MDR-TB was high in this study. The lack of response of MDR-TB patients to CAT II treatment indicates that antibiotic sensitivity testing is essential in patients with CAT I treatment failure.  相似文献   
28.
AIM: To compare the effect of extra-amniotic normal saline solution infusion on its own, and in combination with dexamethasone on the ripening of the cervix and induction of labor. METHODS: A double-blind randomized clinical trial study was performed at Akbar Abadi Teaching Hospital in Tehran, Iran, between March 2002 and March 2003 on 84 pregnant women at a gestational age of 40 weeks or more, and with a Bishop score 相似文献   
29.
30.

Background

Wilson disease (WD) is an autosomal recessive disorder. The WD gene, ATP7B, encodes a copper-transporting ATPase involved in the transport of copper into the plasma protein ceruloplasmin and in excretion of copper from the liver. ATP7B mutations cause copper to accumulate in the liver and brain.

Objectives

We examined the ATP7B mutation spectrum in Wilson disease patients in Iran.

Patients and Methods

Genomic DNA was extracted from patients with Wilson disease. The entire coding region of the ATP7B gene was amplified using PCR and analyzed using direct sequencing.

Results

We identified five novel mutations in 5 Iranian patients with Wilson disease. The first was a transversion, c.2363C > T, which led to an amino acid change from threonine to isoleucine. The second mutation was a deletion, c.2532delA (Val845Ser), which occurred in exon 10. The third mutation was a transition mutation, c.2311C > G (Leu770Leu), which occurred in the TM4 domain of the ATP7B protein. The fourth mutation was a transversion, (c.3061G > A) (Lys1020Lys), in exon 14. Lastly, we identified a transversion, c.3206C > A (His1069Asn) in exon 14 which led to a change in function of the ATP loop domain of the ATP7B protein. The H1069Q mutation was identified as the most common mutation in our study population.

Conclusions

Based on our findings, the H1069Q may be a biomarker that can be used in a rapid detection assay for diagnosing WD patients  相似文献   
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