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Objective:To determine the patterns of resistance to first line anti-tuberculosis(TB)drugs among a collection of Mycobacterium tuberculosis(MTB)isolates from 5 provinces of Iran.Methods:A total of the 6 426 clinical specimens from patients suspected of active TB were collected from March 2010 to June 2012.All specimens were subjected for microscopy and culture tests in the TB centers of studies provinces.Drug susceptibility testing to the first line anti-TB drugs for culture positive MTB was performed on Lwenstein-Jensen(LJ)medium using proportion method.Results:Of 6 426 clinical specimens,261 were culture positive for mycobacteria,of which 252 were MTB and 9 were MOTT(mycobacteria other than tuberculosis).Of 252 MTB isolates.211(83.7%)were pan-susceptible and 41(16.3%)were resistant to at least one drug.Resistance was most common to streptomycin.30 isolates(12.0%),followed by isoniuzid,20isolates(8.0%),rifampin,15 isolates(6.0%)and ethambutol,14 isolates(5.5%).Sixteen(6.3%)MTB isolates were MDR.A clear evidence of heterogeneity amongst the 5 provinces in the proportions with resistance to one or more drugs was observed[χ~2=12.209(4 degrees of freedom),P values=0.015 9].Conclusions:The prevalence of drug resistance in this study area underscoring the need for further enforcement of TB control strategies in the Iran.Drug susceptibility testing for all TB cases to provide optimal treatment,establishing advanced diagnostic facilities for rapid detection of MDR-TB and continuous monitoring of drug resistance are recommended for prevention and control of drug-resistant TB.  相似文献   
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In the current study we investigated the effect of repetitive transcranial magnetic stimulation (rTMS) at different frequencies on chemical kindling in rats. Chemical kindling was induced by injection of pentylenetetrazol (PTZ; 45 mg/kg) at the intervals of 48 h between the injections. In the first experiment, effect of 0.25, 1 and 5 Hz rTMS (four trains of 4 s at motor threshold intensity) on kindling acquisition was investigated. In the second experiment, the stability of rTMS effects was checked in animals of the first experiment during a follow-up period of 2 weeks. Animals received a single dose of PTZ at 7th and 14th day after the last PTZ injection (12th injection) and their seizure parameters were recorded. Obtained results showed that application of rTMS at the frequencies of 0.25 and 1 Hz had anticonvulsant effect and decreased the PTZ kindling acquisition. However, when applied at the frequency of 5 Hz, it had an increasing effect on PTZ kindling rate. During the follow-up study, the seizure severity increased in animals treated with 0.25 Hz rTMS (and somehow in animals treated with 1 Hz rTMS), but did not change in animals treated with 5 Hz rTMS compared to the 12th PTZ injection. Our results showed that rTMS application may have an anticonvulsant effect during chemical kindling acquisition at very low frequency (0.25 Hz) and can increase the seizure severity at high frequency (5 Hz). However, during follow-up, the anticonvulsant effects of rTMS may be converted to proconvulsive effects.  相似文献   
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BackgroundDeep brain stimulation (DBS) has emerged as a potential therapeutic strategy in the treatment of neurological disorders including epilepsy. However, the cellular mechanism responsible for the effects of DBS remains largely undefined. Therefore, using electrophysiological approach, we aimed to determine the antiepileptic effects and restorative potential of low frequency stimulation (LFS) on amygdala kindling-induced changes in electrophysiological properties of rat hippocampal CA1 pyramidal neurons.MethodsAnimals were kindled by electrical stimulation of amygdala in a rapid kindling manner (12 times per day). In one group of animals, immediately after termination of daily 12 rapid kindling stimulations, the kindling site was subjected to 4 packages of LFS at intervals of 5 min (each package contained 200 monophasic square-wave pulses, 0.1 ms pulse duration at 1 Hz). Whole cell patch clamp recording under current clamp conditions was performed on visually identified pyramidal neurons in hippocampal slice preparations obtained from amygdala-kindled rats and the rats receiving LFS.ResultsKindling of the right basolateral amygdala profoundly affected spontaneous firing behavior and repetitive discharge characteristics of pyramidal neuronal electrophysiological properties. Application of LFS at the kindling site almost completely prevented the development of epilepsy and the disruptive effects of kindling on neuronal electrical activity through restoration of the normal electrophysiological characteristics.ConclusionsThe results of this study implied that application of LFS during kindling acquisition prevents the kindling induced changes in functional electrical properties of CA1 pyramidal neurons, suggesting that this action may be involved in the antiepileptogenic mechanism of LFS.  相似文献   
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ObjectiveAdipokines are signaling and mediator proteins secreted from adipose tissue. A novel adipokine, visfatin, was reported as a protein which was mainly expressed in visceral adipose tissue. Controversial results have been shown regarding the changes of adipokines following weight reduction. So we investigated the effects of weight reduction on serum concentrations of adiponectin and visfatin in morbidly obese subjects.Methods35 severely obese patients (26 females and 9 males), aged 15-58 years, were studied. Anthropometric parameters and biochemical parameters as well as adiponectin and visfatin were analyzed before and 6 weeks after weight reduction.ResultsAnthropometric indices decreased significantly. Blood levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride were reduced significantly. The reduction of visfatin and the elevation of adiponectin were significant as well. However, other parameters like fasting glucose and insulin did not change. Moreover, we could not find any significant correlation between the change of serum visfatin and that of adiponectin. Conclusions: 6-week weight reduction after bariatric surgery resulted in decreased serum visfatin and increased adiponectin levels. However, we cannot find any significant correlation between changes of adiponectin, visfatin, BMI, waist circumference, and insulin resistance. Further studies with different design are suggested to clarify these associations.Key Words: Adiponectin, Visfatin, Morbid obesity, Bariatric surgery, Weight loss  相似文献   
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Periprosthetic joint infection (PJI) is one of the most devastating and costly complications following total joint arthroplasty (TJA). Diagnosis and management of PJI is challenging for surgeons. There is no “gold standard” for diagnosis of PJI, making distinction between septic and aseptic failures difficult. Additionally, some of the greatest difficulties and controversies involve choosing the optimal method to treat the infected joint. Currently, there is significant debate as to the ideal treatment strategy for PJI, and this has led to considerable international variation in both surgical and nonsurgical management of PJI. In this review, we will discuss diagnosis and management of PJI following TJA and highlight some recent advances in this field.  相似文献   
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Background

Controversy exists regarding many aspects of decision making pertaining to same-day versus staged bilateral TKA (BTKAs), including patient selection, perioperative management decisions, and other important choices.

Questions/purposes

In the absence of suitable randomized trials, we sought to determine areas of consensus among national experts on the following questions: (1) What are the comparative risks of same-day BTKAs compared with unilateral TKA (UTKA) and staged BTKAs? (2) Who should be considered an appropriate candidate for same-day BTKAs? (3) What constitutes appropriate workup and perioperative management for BTKAs? (4) What is the optimal time between procedures if same-day BTKAs are not deemed appropriate? (5) Are there orthopaedic or rehabilitation considerations for BTKAs that might outweigh medical contraindications?

Methods

In the setting of a consensus conference of national experts in orthopaedic surgery, anesthesiology, perioperative medicine, and epidemiology, the major questions surrounding same-day BTKAs were addressed by using an extensive literature review and the modified Delphi process. The process concluded with a meeting of participants and formulation of consensus statements.

Results

Eighty-one percent of participants agreed that BTKAs are more invasive and complex procedures associated with increased risk for perioperative adverse events compared with UTKA in an unselected group of patients. The consensus group agreed that physicians and hospitals should consider using more restrictive patient selection criteria and exclude those with a modified cardiac risk index greater than 3 to mitigate the potentially increased risk. The majority of the group agreed that perioperative assessment and management should reflect the higher level of acuity of same-day BTKAs. Eighty-one percent of participants agreed that if a patient is not deemed a candidate for same-day BTKAs, a second TKA should be scheduled no sooner than 3 months after the first. The entire group agreed that when there is a conflict between the orthopaedic need and the medical adequacy of same-day BTKAs, the medical concern for the patient’s safety should prevail over the orthopaedic need.

Conclusions

Experts perceived that same-day BTKAs increase medical risk, and thus a systematic approach to the management of patients should be taken to minimize complications.

Electronic supplementary material

The online version of this article (doi:10.1007/s11999-013-2976-9) contains supplementary material, which is available to authorized users.  相似文献   
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