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AIM: Experiential studies suggest that re-expansion of a collapsed lung may result in pulmonary ischaemia-reperfusion injury. We aimed to evaluate the effect of lung re-expansion on urinary lipid peroxidation products in neonates with pneumothorax. METHODS: This study included 20 mechanically ventilated neonates with pneumothorax, and 18 healthy neonates (controls). A chest tube was inserted immediately following the diagnosis of pneumothorax. Urine samples were obtained just before tube thoracostomy (first period), after one hour (second period), every 12 hours by complete reexpansion (third period). Vital signs and ventilatory parameters were recorded. Urinary lipid peroxidation was evaluated by measurement of thiobarbituric acid-reacting substances (TBARS). RESULTS: No significant difference was found between urinary TBARS concentrations in the first, second and third periods (4.08 +/- 2.4 nmol/L, 2.8 +/- 2.3 nmol/L and 3.3 +/- 2.1 nmol/L, respectively). Control TBARS levels (4.1 +/- 2.1 nmol/L) did not significantly differ from those of the neonates with pneumothorax (p > 0.05). The neonates with pneumothorax had higher heart rates compared to the controls (p < 0.01). When compared with controls, the systolic pressure was lower in all periods (p < 0.01), and diastolic blood pressure was lower only in the first and second period (p < 0.05). Oxygen saturation significantly decreased in the first period compared to saturation of the second period and of controls (p < 0.01). Ventilatory parameters did not show any significant difference between the periods. CONCLUSIONS: This prospective study showed that re-expansion of the lung did not significantly affect urinary TBARS concentration in neonatal pneumothorax. Indirectly, short-term lung collapse followed by re-expansion might not cause a clinically significant reperfusion injury in newborns.  相似文献   
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A 19-year-old immunocompetent man was admitted to hospital with diplopia, nausea, vomiting and change in mental status. The patient had a history of tuberculous meningitis that was diagnosed at another hospital 6 months before the present admission, and at that time anti-tuberculosis treatment was initiated using a first-line drug combination. A computed tomography (CT) scan of the brain revealed non-communicating hydrocephalus. A ventriculo-peritoneal shunt was inserted surgically. Two months later, the patient was hospitalized again for fever, dysphagia and left hemiparesis. At that time, his cranial CT findings were within normal limits; however, magnetic resonance imaging (MRI) revealed an irregular multilocular peripheral contrast-enhancing lesion in the posterior fossa. The abscess was surgically drained. The presence of acid-fast bacilli in the abscess material was demonstrated by Ziehl-Neelsen staining. Mycobacterium tuberculosis grew on Lowenstein-Jensen culture medium, and the strain was found to be resistant to isoniazid. One month after the operation, the patient became quadriparetic. Cervical MRI revealed a cervico-thoracic syringomyelitic cavity, after which a syringoperitoneal shunt was placed. Treatment with four drugs was continued for 10 months, and then treatment with three drugs for a total period of 18 months. The patient recovered, with residual quadriparesis. Even though very rare, isoniazid-resistant M. tuberculosis may be the causative agent of progressive tuberculosis.  相似文献   
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SUMMARY: Renal involvement is not uncommon in rheumatoid arthritis (RA). Many RA patients have renal dysfunction either secondary to the drugs used to treat arthritis or because of the chronic inflammation. Renal pathologies have often included amyloidosis, drug-related renal disease and mesangial glomerulonephritis. However, membranoproliferative glomerulonephritis has only been rarely reported. We report a case of rheumatoid arthritis associated with membranoproliferative glomerulonephritis that rapidly progressed to end-stage renal disease.  相似文献   
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Unicornuate uterus with a rudimentary horn is the rarest congenital anatomic anomaly of the female genital system, causing many obstetrical and gynecologic complications. The frequency of this pathology is approximately 1/100 000. A rudimentary horn usually develops following insufficient development of mullerian ducts. These patients present with dysmenorrhea, dyspareunia, and chronic pelvic pain because of endometriosis and rarely with acute abdominal symptoms following distention and torsion of the noncommunicating rudimentary horn. The case of a patient referred for acute abdomen after distention of a noncommunicating rudimentary horn is presented herein.  相似文献   
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Influence of a self-etching primer on compound nerve action potentials   总被引:1,自引:0,他引:1  
The aim of this study was to evaluate the effect of self-etching primers on nerve conductance. A self-etching primer (One Up Bond F) which combines etching and bonding in one step, and a fifth-generation bonding agent (Prime&Bond NT ) were tested. Isolated rat sciatic nerves were placed between two platinum electrodes in a bath containing Tyrode solution. The bonding agents were brought into contact with the nerves and the evoked compound action potentials (CAP) were recorded before and after contact with the materials. One Up Bond F caused total inhibition of the CAP within an average time of 7 min. All CAPs in this group were blocked irreversibly. As with Prime&Bond NT, the reduction in CAP was 45.9% after an application time of 15 min, after which readings were terminated. Recovery of the CAP in this group were maintained after rinsing with fresh tyrode solution. One Up Bond F elicited faster blocking of nerve conductance under the conditions of this model. In the context of dentin desensitization with bonding agents, the self-etching primer may be more effective, clinically.  相似文献   
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Widal test in diagnosis of typhoid fever in Turkey   总被引:4,自引:0,他引:4  
We studied the value of the Widal tube agglutination test for the diagnosis of typhoid fever. The subjects were all adults >18 years of age and were divided into four groups: (i) 317 healthy blood donor controls, (ii) 31 bacteriologically confirmed patients with Salmonella enterica serotype Typhi, (iii) 21 patients with a clinical diagnosis of typhoid fever, and (iv) 41 febrile nontyphoid patients. Blood donor controls were screened with a slide agglutination test for the Salmonella enterica serotype Typhi O and H antigens, and positives were then tested with the Widal test. Acute- and convalescent-phase sera from patients in groups 2, 3, and 4 were obtained 7 to 10 days apart and tested by the Widal test. Using a cutoff of >or = 1/200 for the O antigen test performed on acute-phase serum gave a sensitivity of 52% and a specificity of 88% with a positive predictive value (PPV) of 76% and a negative predictive value (NPV) of 71%. This increased to 90% sensitivity and specificity with a PPV of 88% and an NPV of 93% when the convalescent-phase serum was tested. We concluded that O and H agglutinin titers of > or = 1/200 are of diagnostic significance. The Widal test is easy, inexpensive, and relatively noninvasive. It can be of diagnostic value when blood cultures are not available or practical. The results must be interpreted cautiously because of the low sensitivity of the test. The Widal test done on convalescent-phase serum gave more-reliable results with higher specificity and sensitivity.  相似文献   
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Voxel-based lesion-symptom mapping   总被引:5,自引:0,他引:5  
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A relationship between cyclooxygenase-2 (COX-2) expression and the pathogenesis of colorectal cancer has been reported in recent studies. Moreover, it has been indicated that COX-2 expression may have a prognostic role in colorectal cancer patients. In this study, we investigated the prognostic significance of COX-2 expression in 83 patients with colorectal cancer. COX-2 expression was assessed using immunohistochemical methods and was evaluated by grading both staining intensity and staining extension. The relationships between COX-2 expression and clinicopathological features of the patients and patient survival were evaluated. There was no relationships between COX-2 expression and tumor size (tm < 3 cm or tm > or = 3 cm), tumor histopathological differentiation (poorly differentiated or moderately + well differentiated), number of metastatic lymph nodes (< 4 or 3 > or = 4), histopathology of the tumor, localization of the tumor (colon or rectum), distant metastasis, and vascular invasion of the tumor. In the multivariate analysis, COX-2 expression was not found as an independent prognostic factor. We demonstrated that COX-2 expression was not correlated with clinicopathological characteristics of colon carcinoma and disease outcome.  相似文献   
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