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941.
J C Ho M Chan-Yeung S P Ho J C Mak M S Ip G C Ooi M P Wong K W Tsang W K Lam 《The European respiratory journal》2007,29(2):273-278
The present study aimed to determine the alterations of antioxidant activities in erythrocytes from patients with nonsmall cell lung carcinoma (NSCLC). A comparative study of the systemic antioxidant activities in red blood cell lysate from subjects with NSCLC and healthy control subjects was conducted. The antioxidants catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured using chemical kinetic reactions under spectrophotometry. In total, 189 cases of mostly advanced-stage IIIB or stage IV NSCLC and 202 healthy controls were studied. In subjects with lung cancer, there was similar catalase activity, lower SOD activity (median (interquartile range) 13.4 (9.0-27.2) versus 48.7 (27.0-64.3) U x (ghaemoglobulin(Hb)(-1)), and higher GPx activity (175.2 (126.6-288.3) versus 49.2 (39.5-59.2) mU x (gHb)(-1)) compared with controls. The antioxidant activities in lung cancer subjects were not associated with age, sex, smoking status, or tumour cell types. However, more advanced disease (stage IV compared with stage IIIB) was associated with lower SOD activity. Using multivariable analysis, the presence of lung cancer independently predicted SOD and GPx activities. In conclusion, nonsmall cell lung carcinoma in Chinese subjects is associated with alterations in systemic antioxidant activities, which may play an important role in carcinogenesis. 相似文献
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943.
Presurgical ultrasound-assisted neuro-examination in the surgical repair of peripheral nerve injury.
In spite of electrodiagnostic examinations, the determination of the precise localization of the injured site along the involved peripheral nerve may remain obscure or uncertain. Before starting the operation, a surgeon should have knowledge about the type of injury, the position of the proximal and distal nerve stumps, and the presence or absence of a neuroma and excessive perilesional scar tissue formation for orientation and planning of the surgical intervention. We hypothesized that real-time ultrasound could be helpful in the determination of the type of injury, the localisation of proximal and distal nerve stumps, as well as for diagnosing a neuroma. Fourteen patients with traumatic peripheral nerve injuries that were verified by neurological examinations and electrodiagnostic tests underwent surgical repair, and were examined by ultrasound before and during the surgical intervention. Visualisation of the injured site, the type of the injury, the position of the nerve stumps and the diagnosis of the neuroma were reliably feasible in all the patients by using ultrasonography. Axonal swelling of a nerve was diagnosed in 4 (29 %) patients, a stump neuroma was diagnosed in 3 (21 %) patients, a total nerve interruption (neurotmesis in the Seddon classification) was diagnosed in 9 (64 %) patients, and surrounding scar tissue was diagnosed in 5 (35 %) patients. Presurgical and intraoperative ultrasound-assisted neuroexamination is a useful diagnostic method in the determination of the precise localisation of the injured site, the type of injury, the position of stumps, and the diagnosis of a neuroma. The use of preoperative and intraoperative ultrasound can enhance the orientation of the surgeon to the surgical field. The application of our method to our patients shows that presurgical ultrasonographic neuroexamination can be used in the surgical repair of peripheral nerve injury. 相似文献
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948.
M. H. Wernitz S. Swidsinski K. Weist D. Sohr W. Witte K-P. Franke D. Roloff H. Rüden S. K. Veit 《Clinical microbiology and infection》2005,11(6):457-465
Screening of potential MRSA-positive patients at hospital admission is recommended in German and international guidelines. This policy has been shown to be effective in reducing the frequency of nosocomial MRSA transmissions in the event of an outbreak, but the influence of screening on reducing hospital-acquired MRSA infections in a hospital setting where MRSA is endemic is not yet well-documented. This study describes the effect of hospital-wide screening of defined risk groups in a 700-bed acute care hospital during a period of 19 months. In a cohort study with a 19-month control period, the frequencies of hospital-acquired MRSA infections were compared with and without screening. In the control period, there were 119 MRSA-positive patients, of whom 48 had a hospital-acquired MRSA infection. On the basis of this frequency, a predicted total of 73.2 hospital-acquired MRSA infections was calculated for the screening period, but only 52% of the expected number (38 hospital-acquired MRSA infections) were observed, i.e., 48% of the predicted number of hospital-acquired MRSA infections were prevented by the screening programme. The screening programme was performed with minimal effort and can therefore be recommended as an effective measure to help prevent hospital-acquired MRSA infections. 相似文献
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950.