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A fatal case of primary amebic meningoencephalitis (PAM) in a 5-month-old infant is described. The disease may have been contracted during bathing. The source of water was from an artificial well. The clinical presentation, the isolation of the ameba from the cerebrospinal fluid, the poor response to amphotericin B, and the ultimate fatal outcome are all consistent with the diagnosis of PAM. On the basis of its ability to grow at temperatures above 30 degrees C, the morphology of the trophozoite, and the presence of flagellate forms, the ameba was identified as Naegleria fowleri. Pathogenic N. fowleri amebae were recovered from samples of water from the well. To our knowledge this case represents the second case of PAM in an infant in the absence of the history of swimming.  相似文献   
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Trigger factor is a ribosome-associated peptidyl-prolyl cis/trans isomerase that is highly conserved in most bacteria. A gene, designated ropA, encoding an apparent trigger factor homologue, was identified in Streptococcus mutans, the primary etiological agent of human dental caries. Inactivation of ropA had no major impact on growth rate in planktonic cultures under the conditions tested, although the RopA-deficient mutant formed long chains in broth. Deficiency of RopA decreased tolerance to acid killing and to oxidative stresses induced by hydrogen peroxide and paraquat, and it reduced transformation efficiency about 200-fold. Addition of synthetic competence-stimulating peptide to the culture medium enhanced transformability of both the mutant and wild-type strains, although the ropA strain did not attain levels of competence observed for the parent. Loss of RopA decreased the capacity of S. mutans to form biofilms by over 80% when cultivated in glucose, but it increased biofilm formation by over 50% when sucrose was provided as the carbohydrate source. Western blot analysis revealed that the expression of glucosyltransferases B and D was lower in the RopA-deficient mutant. These results suggest that RopA is a key regulator of acid and oxidative stress tolerance, genetic competence, and biofilm formation, all critical virulence properties of S. mutans.  相似文献   
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Objective: We aimed to determine the value of autopsy in fetuses with antenatally diagnosed oligohydramnios.

Patients and methods: We evaluated all fetal losses over a period of 6.5 years. Those with oligohydramnios on antenatal scan were critically analyzed. Oligohydramnios was defined as amniotic fluid index of less than five objectively or as an obvious lack of liquor at subjective assessment. A detailed postmortem examination was carried out in all the fetuses after obtaining an informed consent.

Results: Fetal autopsy was conducted in 255 cases. Fifty-five (21.5%) fetuses were diagnosed to have oligohydramnios on antenatal ultrasonography. On analysis of antenatal causes of oligohydramnios, maternal/placental factors were noted in 18%, ultrasound findings known to affect amniotic fluid in 27% while cause remained unidentified in 54.5% of cases. On autopsy, fetal malformations were noted in 61.8% cases, intrauterine growth retardation in 21.8% fetuses and no obvious malformations in 16.3% fetuses. Renal anomalies were noted in 40% cases and non-renal malformations in 21.8% cases.

Conclusion: The postmortem examination helped us to identify the cause of fetal loss in 46 (83.6%) fetuses with antenatal oligohydramnios. A working diagnosis could not have been established without autopsy in 19 (34.5%) cases.  相似文献   
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Nasopharyngeal carcinoma may present with bewildering arrays of signs & symptoms. Diagnosis often become difficult and requires a high degree of clinical suspicion for the disease. We here by present a case of 11 year old girl which have unusual presentation.  相似文献   
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Objective  A climical study was undertaken to analyze the age, sex distribution and symptomatology, sites of involvement and the prognosis of the common types of benign lesions of larynx. Study Design  A five year retrospective study from 1997 to 2002. Setting  KMC Hospital Attavar —A tertiary referral hospital. Patients  A total of 42 patients with benign laryngeal lesions were included based on symptomatology such as hoarseness of voice, foreign body sensation, throat pain, neck mass and cough and with positive clinical findings on indirect laryngoscopy and neck examination. The patients ranged from 7–80 years. All non-operative cases and malignant cases were excluded. Diagnostic hematological and radiological investigations and therapeutic microlyryngoscopic procedures were employed. Results  A male preponderance with M:F ratio of 3∶1 was observed. Majority of the patients were in the 30–40 age group. Vocal polyps were the commonest type of lesion. In our study, hoarseness of voice, cough, foreign body sensation and throat pain proved to be the commonest symptoms. Conclusions  Micro laryngeal surgery and voice rest offer a cost effective, useful and safe method for management of benign laryngeal lesions.  相似文献   
28.
The efficacy of supravital staining in the detection of malignancies in oro and oropharyngeal lesions and its role in the detection of malignant changes in premalignant lesions were studied. This prospective study comprises 90 cases of clinically suspicious lesions and it was done over a period of 3 years. Most of the patients had multiple risk factors for the development of malignancy. All underwent staining with a modified solution of 1% toluidine blue (TB). In our study the overall sensitivity was 97.29% and the specificity was 62.5%.  相似文献   
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Background Myasthenia gravis is a challenging clinical condition due to its neuromuscular involvement. We sought to compare two non-muscle relaxant anesthetic techniques in patients undergoing trans-sternal thymectomy, evaluating the intra and postoperative conditions including extubation in the operating room. Methods Eight consecutive myasthenic patients undergoing trans-sternal thymectomy were prospectively randomized into two groups: propofol and sevoflurane. In both groups anesthesia was induced with propofol (2mg. Kg−1) and intubation performed after topical anesthesia of the airway with lignocaine. Anesthesia was maintained in the propofol group (4 patients) with continuous propofol infusion (3–10 mg. Kg−1., hr−1) with oxygen and nitrous oxide and in the sevoflurane group (4 patients), with sevoflurane (end tidal 1–1.5%) in oxygen and nitrous oxide. Fentanyl was used for analgesia in both the groups. Intubating conditions, haemodynamic changes, neuromuscular transmission along with postoperative intensive care unit stay were evaluated. Data were evaluated using ANOVA, Chi-square test and Student'st test. Results Intubating conditions were good in all patients. There were no significant haemodynamic changes. All patients were extubated in the operating room and none had to be re-intubated for postoperative respiratory depression. Neuromuscular transmission showed minimal changes and at the end of the procedure the recovery was complete in all the patients. There were no other significant differences between the two groups studied. Conclusion These two anesthetic techniques allow early extubation of myasthenic patients in the operating room.  相似文献   
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We report a patient with glioblastoma multiforme who was subsequently diagnosed to have Wilson's disease. Immunohistochemical studies of the tumor revealed high (> 60%) labeling index for p53 and Rb retinoblastoma protein. Whether this association is like the co-occurrence of retinoblastoma and Wilson's disease due to possible somatic mutation in chromosome 13 needs to be explored.  相似文献   
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