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Drug-resistant tuberculosis is a serious problem throughout the world. Resistance to Rifampicin (RIF) is mainly caused by the mutations in the rpoB gene coding the beta-subunit of RNA polymerase. In this study, we aimed to detect the distribution of rpoB gene mutations in 80 RIF-resistant clinical Mycobacterium tuberculosis (MTB) isolates from Turkey. The rpoB gene was amplified by PCR and mutations leading to RIF resistance were determined by automated sequence analysis. A total of 72 of the 80 isolates (90%) were found to carry mutations in the amplified region, whereas eight isolates (10%) carried no mutations. Overall, 24 different missense mutations affecting 14 codons, and two deletion mutants were identified. Nine new mutations, six in the hot-spot region and three outside this region, were found. The codon numbers of the most frequently encountered mutations were 531 (51.4%), 526 (18.1%), 516 (13.9%), and 513 (12.5%). As a result, 90% of the RIF-resistant MTB isolates from the Turkish patients were found to carry a mutation in the rpoB gene, Ser531Leu being the most frequent one. Although molecular methods identify mutations leading to RIF resistance very quickly, results of the antimycobacterial susceptibility tests must be taken into consideration for the patients carrying no mutations in this region.  相似文献   
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In this study, blood agar was used instead of 7H10 agar for the susceptibility testing of 34 clinical isolates of Mycobacterium tuberculosis to isoniazid (INH) and rifampin (RIF) in accordance with the NCCLS. The BACTEC 460 TB system (Becton Dickinson, Sparks, Md.) was used as a "gold standard." Results for both media were in agreement for RIF and INH at 100 and 94.1%, respectively. For INH, the specificity, sensitivity, positive predictive value, and negative predictive value were found to be 71.4, 100, 93.1, and 100%, respectively, while these values were 100% for RIF. In addition, the results of the susceptibility test performed with blood agar were obtained on day 14 of incubation. In conclusion, results were obtained much earlier with blood agar (2 weeks) than with 7H10 agar (3 weeks), and the results of this study suggest that blood agar may be used as an alternative medium for the susceptibility testing of M. tuberculosis to INH and RIF.  相似文献   
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Primary hemangiopericytoma of the rib is extremely rare and only a few cases have been reported. A 62-yr-old man presented with an aching chest pain and dyspnea. Thoracic computed tomography revealed a homogenous mass expanding the right seventh rib. A diagnosis of hemangiopericytoma was established by percutaneous needle biopsy. Preoperative embolization of the feeding vessels of the tumor was performed in order to prevent perioperative bleeding. There was no significant bleeding during the surgery, where complete resection of the tumor with 7th to 9th ribs with a surgical margin of 5 cm was performed. Postoperative course was uneventful and there has been no recurrence for thirteen months. To our knowledge, there has been no report to apply a preoperative embolization of a primary hemangiopericytoma of the rib.  相似文献   
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Summary X-irradiation of Syrian hamster cells transformed by simian virus 40 which exhibited evidence of the presence of the viral genome was consistently followed by extensive polynucleate giant cell formation.With the possible exception of cells derived from an adenovirus 12-induced tumor this phenomenon has not been observed in other Syrian hamster cell systems, i.e. lines of oncogenic cells originally exposed to SV40 virus but in which no evidence of the viral genome could be subsequently demonstrated; cells transformed by polyoma virus; a line of oncogenic cells not associated with virus; continuous lines and primary cultures of normal cells.Extensive post-irradiation polynucleate giant cell formation did not occur in SV40-transformed lines of human cells; in primary cultures of human cells of various tissue origin; in lines of cells derived from human malignant tumors. A line of African green monkeys cells (Cercopithecus aethiops) after irradiation also failed to react in this manner.Treatment with colchicine of SV40-transformed hamster and human cells induced extensive polynucleate giant cell formation only in hamster cell systems. Therefore the effect of colchicine appears to parallel that of irradiation.Various possible mechanisms to account for the phenomenon of post-irradiation and colchicine-induced polynucleate giant cell formation in hamster cells bearing the SV40 genome are suggested and discussed.Dedicated to the Honor of the 60th birthday of ProfessorSven Gard. Supported in part by Grant No. AI-01992-08 from the National Institute of Allergy and Infectious Diseases, National Institutes of Health, U.S.P.H.S. Bethesda, Maryland.Post Doctoral Research Fellow, Rockefeller Foundation.U.S.P.H.S. Research Development Career Award No.5-K3-AI-14,617,02.U.S.P.H.S. Special Fellow, No. 2-F3-CA-13,444-03, National Cancer Institute, National Institutes of Health.  相似文献   
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BACKGROUND: On February 19, 2003, four patients (patients 1-4) in the neurology ward underwent cranial magnetic resonance angiography (MRA) and developed fever within 1 hour afterward. Klebsiella oxytoca was isolated from blood cultures of patients 1 through 3. OBJECTIVE: To identify the source of this cluster of nosocomial K. oxytoca bloodstream infections. DESIGN: Outbreak investigation. SETTING: A 1,000-bed university hospital. METHODS: The infection control team reviewed patient charts and interviewed nursing staff about the preparation and administration of parenteral fluids. The procedure of cranial MRA was observed. Arbitrarily primed polymerase chain reaction (AP-PCR) was performed to show the clonal relationship among these three strains. RESULTS: AP-PCR revealed that three K. oxytoca isolates had the same molecular profile. Cranial MRA was found to be the only common source among these patients. During MRA, before injection of the contrast medium, normal saline solution was infused to check the functioning of the intravenous catheter. Use of the solution for multiple patients was routine, but the access diaphragm of the bottle was not cleansed. The bottle of normal saline solution used on February 19 had already been discarded and the culture sample taken from the solution on the day of observation was sterile. CONCLUSIONS: We speculate that normal saline solution became contaminated during manipulation and that successive uses might have been responsible for this cluster. Poor aseptic techniques employed during successive uses appear to be the most likely route of contamination. Use of parenteral solutions for multiple patients was discontinued.  相似文献   
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Autoimmune estrogen dermatitis is a cyclical cutaneous eruption that occurs premenstrually and goes to the rapid resolution within a few days of menstrual cycles. The disorder has variable clinical manifestations consisting of macules, papules, vesicles, urticarial lesions, bullae, eczematous plaques, and erythema multiforme-like lesions. Herein, we present a case of a 30-year-old woman with attacks of edema and erosions involving the oral and genital mucosal sites on every first day of her menstruation period. She had also multiple endocrinological problems such as hypotroidism and infertility. To determine the sex hormon sensitivity, intradermal skin tests were performed. Based on her personal history and skin test findings, a diagnosis of autoimmune estrogen dermatitis was made. After the oophorectomy, she was free from the skin and mucosal symptoms. We propose that it is important to suspect the diagnosis of autoimmune estrogen dermatitis in patients who present with recurrent cylic eruptions and it must be kept in mind that these patients might have a concomitant infertility.  相似文献   
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Convulsions are one of the frequently seen problems for a neurologist in the daily routine. It is difficult to distinguish the seizure from pseudo-seizure because of lack of conclusive tests. The aim of this study is to investigate the relationship between seizure types and seizure periods by studying IMA serum levels in children having seizure. Two groups were included (patients and control) in our study. The patient group consisted of the children admitted to Pediatric Emergency Care during January 2008–January 2010 with seizure and the control group consisted of healthy children. Serum Ischemia modified albumin (IMA) level in the group having seizures was 99.7 and 83.2 U/ml in the control group. In the comparison of the patient and control groups, significant differences were found between their IMA values (p = 0.000). There was a significant difference between IMA values of the group having generalized tonic–clonic seizures and those of the control group (p = 0.001). In comparison of the IMA values of the group having febrile convulsions and those of the control group, a significant difference was determined (p = 0.011). It has been shown that if the seizure was prolonged over 5 min, IMA level increased, and there was a significant difference between the groups experiencing over 5 min of seizures and the groups experiencing less than 5 min of seizures (p = 0.001). An increase in IMA levels in febrile convulsion supports the hypoxia development in the brain during the seizure. Serum IMA levels increased with the elongation of the seizure period and may be an indicator for status epilepticus.  相似文献   
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