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Burkholderia pseudomallei infection of the central nervous system (CNS) is rare with less than 50 cases reported over the last 30 years. The retrospective melioidosis study at University Malaya Medical Centre has documented three cases of CNS melioidosis out of more than 160 cases of melioidosis since 1978. There were two patients with brain abscess and one with spinal epidural abscess. The predisposing factors were: one patient was an aboriginal farmer and the other two were diabetic. Their age ranged from 17 to 45 years. Prominent neurological features were limb weakness, cranial nerve palsy (6th and 7th) and visual disturbance. CT brain scan and MRI spine showed abscess formation, subdural collection, and spinal epidural collection, osteomyelitis of vertebra and occipital bone and also sagital sinus thrombosis. All these patients underwent surgical drainage leading to bacteriological diagnosis as well as appropriate long-term antibiotic therapy. All had good recovery at 6 months after completion of treatment.  相似文献   
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A molecular clone containing a 5.8 kb Eco RI fragment was isolated from a genomic library of the rodent malarial parasite Plasmodium yoelii. The P. yoelii genome contains about 150 copies of this sequence, making up almost 3% of the DNA. These sequences are tandemly arrayed in head-to-tail configurations with the unit length of the repeat being 5.8 kb. Several poly(A+) RNAs of P. yoelii ranging from 1.6 to 0.3 kb are recognized by the 5.8 kb clone. Five additional species of malarial parasites (P. chabaudi, P. berghei, P. falciparum, P. knowlesi, and P. cynomolgi) contain tandemly repeated arrays of sequences having the same unit length of 5.8 kb, which readily hybridize to the sequence cloned from P. yoelii.  相似文献   
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Kinetic studies of the polymerization of 1-octene with the Ziegler-Natta catalyst systems VOCl3—AlEt3 (I) and VOCl3—AlEt2Br (II) are reported. The effect of the various parameters such as the Al/V ratio, catalyst and monomer concentrations, reaction time, aging time and temperature on rate of reaction and molecular weight of polymer were studied. Each of these parameters has a profound effect on the polymer yield and the rate of the reaction for both systems. The rate of polymerization increases linearly with increasing temperature, catalyst and monomer concentrations. The reaction is first order with respect to both the monomer and the catalyst concentration in the two catalyst systems studied. From the Arrhenius plot the overall activation energy of polymerization for the two systems was found to be 51,2 and 43,5 kJ/mol, respectively. The mechanism of polymerization is discussed on the basis of the dependence of the polymerization rate on the alkylaluminium concentration.  相似文献   
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A prospective, double-blind, randomized, placebo-controlled study was performed to evaluate the effect of antibiotic prophylaxis in ear surgery. The present study reports on the results of 750 patients, half of whom received cefuroxime for 1 day, the other half, placebo. All postoperative infections occurring within 2 weeks after the intervention were recorded, together with several preoperative and perioperative parameters. It is concluded that exploratory tympanoplasties (including stapedotomy) and “dry perforation” tympanoplasties should be considered “clean” operations according to the American National Research Council and do not benefit from antibiotic prophylaxis. On the other hand, tympanoplasties performed on draining ears and on ears with cholesteatoma should be considered “dirty” operations for which antibiotic prophylaxis may decrease the postoperative infection rate by factor 3. All postoperative infections healed without sequels under proper treatment, except for three that resulted in graft necrosis-one in the placebo group and two in the cefuroxime group. In consequence, prophylaxis may not be mandatory in the dirty group, although the authors advocate its use for the sake of patient and surgeon comfort.  相似文献   
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An investigation was carried out in an organized dairy farm of Tamil Nadu State, India where cattle were reported to have eye infection. Preliminary clinical intervention revealed that the animals had infectious bovine keratoconjunctivitis (IBK). Isolation and identification of pathogen from eye swab revealed the presence of Moraxella spp. On further molecular characterization by Polymerase chain reaction (PCR) suggested that the isolate as Moraxella bovoculi. PCR followed by sequencing was carried and the results showed that the isolate was M. bovoculi and the sequence was submitted in the GenBank with the sequence id. KX121047. Animals were treated with antibiotics as per the results from antibiotic sensitivity test and treatment yielded good results as the animals responded to treatment. This report is the first of its kind from India as there was no previous report regarding M. bovoculi from the country. Further insights into the bacterial genome can aid in identification of the genes or regions involved in pathogenesis of IBK and also to carve out the prevention and control strategies of IBK.  相似文献   
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A 26 year old Saudi man with features of both Loeffer's endocarditis and endomyocardial fibrosis presented with mild symptoms and pulmonary emboli. Echocardiographic examination showed obliteration of the right ventricular apex by an attached mass. The results of haemodynamic studies were somewhat abnormal and medical treatment was started. Despite anticoagulation with warfarin the patient's condition deteriorated rapidly over a four month period after a further episode of pulmonary embolism and the development of pulmonary hypertension. Two haemodynamic studies performed four months apart were typical of pulmonary hypertension and later right ventricular failure; they showed none of the characteristics of restriction. Pulmonary embolectomy was attempted but there was no cleavage plane between the organised thrombi and the endothelium of the pulmonary artery. The patient died of severe pulmonary hypertension and right ventricular failure several days after operation. Surgical intervention in the early stages of right-sided endomyocardial fibrosis might have prevented the development of pulmonary embolism and pulmonary hypertension.  相似文献   
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