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Detection of Vi-negative Salmonella enterica serovar typhi in the peripheral blood of patients with typhoid fever in the Faisalabad region of Pakistan
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Baker S Sarwar Y Aziz H Haque A Ali A Dougan G Wain J Haque A 《Journal of clinical microbiology》2005,43(9):4418-4425
The synthesis and transportation proteins of the Vi capsular polysaccharide of Salmonella enterica serovar Typhi (serovar Typhi) are encoded by the viaB operon, which resides on a 134-kb pathogenicity island known as SPI-7. In recent years, Vi-negative strains of serovar Typhi have been reported in regions where typhoid fever is endemic. However, because Vi negativity can arise during in vitro passage, the clinical significance of Vi-negative serovar Typhi is not clear. To investigate the loss of Vi expression at the genetic level, 60 stored strains of serovar Typhi from the Faisalabad region of Pakistan were analyzed by PCR for the presence of SPI-7 and two genes essential for Vi production: tviA and tviB. Nine of the sixty strains analyzed (15%) tested negative for both tviA and tviB; only two of these strains lacked SPI-7. In order to investigate whether this phenomenon occurred in vivo, blood samples from patients with the clinical symptoms of typhoid fever were also investigated. Of 48 blood samples tested, 42 tested positive by fliC PCR for serovar Typhi; 4 of these were negative for tviA and tviB. Three of these samples tested positive for SPI-7. These results demonstrate that viaB-negative, SPI-7-positive serovar Typhi is naturally occurring and can be detected by PCR in the peripheral blood of typhoid patients in this region. The method described here can be used to monitor the incidence of Vi-negative serovar Typhi in regions where the Vi vaccine is used. 相似文献
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Wani T Kakru DK Shaheen R Nazir A Lone R Shakeel S Shah A 《Indian journal of pathology & microbiology》2004,47(1):76-77
Endocarditis is a rare complication of typhoid fever. We report a case in which Salmonella enterica serotype typhi was isolated from a case of endocarditis. The isolate was resistant to ampicillin, chloramphenicol and ciprofloxacin but sensitive to ceftriaxone, amikacin and gentamicin. 相似文献
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Amyn A. Malik Neel R. Gandhi Timothy L. Lash Lisa M. Cranmer Saad B. Omer Junaid F. Ahmed Sara Siddiqui Farhana Amanullah Aamir J. Khan Salmaan Keshavjee Hamidah Hussain Mercedes C. Becerra 《Emerging infectious diseases》2021,27(3):805
In Karachi, Pakistan, a South Asian megacity with a high prevalence of tuberculosis (TB) and low HIV prevalence, we assessed the effectiveness of fluoroquinolone-based preventive therapy for drug-resistant (DR) TB exposure. During February 2016–March 2017, high-risk household contacts of DR TB patients began a 6-month course of preventive therapy with a fluoroquinolone-based, 2-drug regimen. We assessed effectiveness in this cohort by comparing the rate and risk for TB disease over 2 years to the rates and risks reported in the literature. Of 172 participants, TB occurred in 2 persons over 336 person-years of observation. TB disease incidence rate observed in the cohort was 6.0/1,000 person-years. The incidence rate ratio ranged from 0.29 (95% CI 0.04–1.3) to 0.50 (95% CI 0.06–2.8), with a pooled estimate of 0.35 (95% CI 0.14–0.87). Overall, fluoroquinolone-based preventive therapy for DR TB exposure reduced risk for TB disease by 65%. 相似文献
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Andrea C. Perez Aamir M. Khawaja Clive P. Page William Paul 《European journal of pharmacology》1997,330(2-3):241-246
Plasma protein extravasation has been measured in guinea pig skin using
-albumin and blood flow using
enon (
e) clearance. The nitric oxide (NO) synthase inhibitors NG-nitro-
-arginine methyl ester (
-NAME), NG-monomethyl-
-arginine (l
NMMA) and NG-nitro-
-arginine (
-NOArg) and the α-adrenoceptor agonist, phenylephrine, inhibited bradykinin induced plasma protein extravasation when co-injected with the peptide. The inhibitory effects of
-NAME and
-NOArg lasted for up to 8 and 4 h, respectively, whereas phenylephrine and
-NMMA had no persistent inhibitory effects. When co-injected with
e,
-NAME,
-NMMA,
-NOArg and phenylephrine, but not
-NAME, produced significant reductions in skin blood flow. When injected prior to
e,
-NAME and
-NOArg, but not phenylephrine or
-NMMA, significantly reduced flow. The effect of
-NAME on flow was not significant at 8 h. Thus, although the inhibitory effects of the NO synthase inhibitors on mediator induced plasma protein extravasation show correlations with their effects on blood flow, the persistent effect of
-NAME on exudation appears to extend beyond its effect on flow. 相似文献
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Nazir Ahmad Tahmina Ruhi 《Indian journal of otolaryngology and head and neck surgery》1994,46(2):96-100
BAEPS are coming up as an important investigatory tool in the hands of present clinicians and have a diagnostic and prognostic significance. The present study was carried on 25 patients. BAEPS were recorded at the time of admission and analysed. Absent BAEPS were associated with high mortality. Abnormal BAEPS were seen in infective and CVA group. Followup BAEPS showed no change in those patients who died. 相似文献
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Jonathan D. Adachi Professor Everett J. Sargeant Professor Margaret A. Sagle Associate Professor David Lament Assistant Professor Paul D. Fawcett Obstetrician Gynaecologist William G. Bensen Associate Clinical Professor Matthew McQueen Chief Director Professor Darius J. Nazir Clinical Chemist Associate Professor Charles H. Goldsmith Professor Head 《BJOG : an international journal of obstetrics and gynaecology》1997,104(1):64-70
Objective To assess the effects of medroxyprogesterone acetate on bone density in women who have had a hysterectomy
Design Randomised, double-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg, 20 mg or placebo as an adjunct to oestrogen therapy.
Participants One hundred and twenty-three women, aged 18 to 45 years and currently receiving daily oestrogen, who presented at a university-based rheumatology practice.
Interventions The women were randomly assigned to receive either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beginning on day 15 of each month for one year. Forty-one women were randomised into each group.
Main outcome measure The primary outcome measurement was the percentage of change from baseline in bone mineral density of the lumbar spine (L2–L4). Secondary outcome measures included differences in femoral neck bone density, cholesterol and triglyceride levels between groups.
Results At one year, change in bone mineral density did not differ between either the treatment or placebo groups. Medroxyprogesterone acetate 20 mg and 10 mg led to statistically significant reductions in very low density lipoprotein cholesterol, total triglycerides, and very low density lipoprotein triglycerides when compared with placebo. Medroxyprogesterone acetate 20 mg also led to a statistically significant reduction in high density lipoprotein cholesterol, high density lipo-protein-2 cholesterol, and high density lipoprotein-2 triglycerides.
Conclusions Medroxyprogesterone acetate at either dose as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, however, did reduce high density lipoprotein cholestrol and therefore may increase cardiovascular risk. 相似文献
Design Randomised, double-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg, 20 mg or placebo as an adjunct to oestrogen therapy.
Participants One hundred and twenty-three women, aged 18 to 45 years and currently receiving daily oestrogen, who presented at a university-based rheumatology practice.
Interventions The women were randomly assigned to receive either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beginning on day 15 of each month for one year. Forty-one women were randomised into each group.
Main outcome measure The primary outcome measurement was the percentage of change from baseline in bone mineral density of the lumbar spine (L2–L4). Secondary outcome measures included differences in femoral neck bone density, cholesterol and triglyceride levels between groups.
Results At one year, change in bone mineral density did not differ between either the treatment or placebo groups. Medroxyprogesterone acetate 20 mg and 10 mg led to statistically significant reductions in very low density lipoprotein cholesterol, total triglycerides, and very low density lipoprotein triglycerides when compared with placebo. Medroxyprogesterone acetate 20 mg also led to a statistically significant reduction in high density lipoprotein cholesterol, high density lipo-protein-2 cholesterol, and high density lipoprotein-2 triglycerides.
Conclusions Medroxyprogesterone acetate at either dose as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, however, did reduce high density lipoprotein cholestrol and therefore may increase cardiovascular risk. 相似文献
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Kimberly K. Engelman PhD ; Edward F. Ellerbeck MD MPH ; Denise Perpich MPH ; Niaman Nazir MBBS MPH ; Kevin McCarter PhD ; Jasjit S. Ahluwalia MD MPH 《The Journal of rural health》2004,20(1):36-42
CONTEXT: Breast cancer screening rates are lower in rural communities. Although studies have addressed barriers to mammography for rural residents, physician practice barriers have received less attention. PURPOSE: Controlled clinical trials have shown that the use of office reminder systems in primary care practices is related to increased clinical care rates. Therefore, we compared office systems use in primary care practices located in rural and urban communities and assessed the impact of these systems on rural-urban differences in mammography utilization. METHODS: We identified female Kansas Medicare beneficiaries aged 65 to 79 from Medicare claims data (N = 24,030) and determined which beneficiaries received a mammogram between April 1, 1999, and March 31, 2001. We linked beneficiaries to their primary care providers and obtained surveys from 180 primary care practices on their use of office reminder systems. FINDINGS: Mammography rates ranged from 20% to 92% (mean = 65%) among the 180 practices. Flowsheets with a mammography prompt were used by 33% of the practices, 38% utilized nonphysician staff to identify women due for mammograms, and 15% used computerized reminder systems. Urban practices used flowsheets more often than rural practices (44% versus 16%, P < 0.001). A multivariable regression model demonstrated higher mammography rates in urban practices, group practices, and practices using mammography flowsheets. CONCLUSIONS: Despite success in randomized controlled trials, reminder systems are not used often by primary care providers and are used even less often in rural compared to urban practices. Consistent implementation may be a major barrier to the successful adaptation of flowsheets by primary care offices. 相似文献
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