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991.

Background  

Sciatic nerve block is a commonly used technique for providing anesthesia and analgesia to the lower extremity. It is classically performed through posterior or lateral approaches. However, an anterior approach should be considered in certain conditions where patient positioning would be complicated. The success rate of the sciatic nerve block with previously defined approaches has been reported to be low, however, the complication rate with such approaches has been found to be high. Therefore, we aimed to conduct an anatomical study defining a new anterior approach to block the sciatic nerve and also to examine if the femoral nerve can be blocked via the same approach.  相似文献   
992.
A mortality study of electrical utility workers in Québec.   总被引:2,自引:2,他引:0       下载免费PDF全文
OBJECTIVES--The objective of this study was to investigate the mortality of electrical utility workers exposed to electric and magnetic fields. METHODS--A historical cohort mortality study was carried out on 21,744 workers who were employed in an electrical company in the province of Québec between 1970 and 1988. The last job held by each study subject was coded. A job exposure matrix (JEM) was used to estimate the exposure to 60 Hz electric and magnetic fields, and pulsed electromagnetic fields (as recorded by the PEMF (POSITRON) meter) in this job. Standardised mortality ratios (SMRs) were calculated relative to Québec men. Because the exposure was exclusively among blue collar workers, the remainder of the analyses by exposure were restricted to them. Rate ratios (RRs) in the exposed groups relative to the background groups were estimated with Poisson regression. There were 1582 deaths by the end of follow up. RESULTS--SMRs were almost all below one and never substantially increased, although there were a few increased rate ratios (RRs). There was a significant RR of 2.00 (95% confidence interval (95% CI) 1.37-2.93) for deaths caused by accidents and violence in workers exposed to magnetic fields, RR of 1.82 (95% CI 1.25-2.65) for electric fields, and RR of 1.62 (95% CI 1.13-2.32) for pulsed electromagnetic fields. Occupational accidents related to power lines explain some of the excess of deaths from accidents and violence. Some association was found between magnetic fields and leukaemia, brain cancer, and suicide, between electric fields and brain cancer and suicide, and between pulsed electromagnetic fields and lung cancer, but these were not significant. CONCLUSION--These results are broadly reassuring that major causes of death are not strongly associated with exposure to electric and magnetic fields, but small numbers and approximate exposure assessments preclude the denial of any risk, in particular if it were to affect a rare cause of death.  相似文献   
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The stabilities of many key proteins are regulated, e.g. via ubiquitination and proteasomal degradation, with important biological consequences. We present a convenient method that allows the analysis and comparison of protein stabilities during embryogenesis using early zebrafish development as a model system. Basically, this method involves ectopic overexpression of epitope-tagged proteins via mRNA injections in one-to-four-cell stage embryos and subsequent protein detection after various time points. Indeed, the protein stability of the ubiquitin ligase RLIM, which is able to autoubiquitinate and target itself for proteasomal degradation, was much shorter when compared to a protein consisting of a Myc epitope-tag and a nuclear localization domain. Thus, this method may be used more widely for the study of developmental protein stability.  相似文献   
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997.
Treatment of neglected high dislocation of the hip is difficult in adults. We performed hip reconstruction osteotomy, consisting of a proximal abduction and extension osteotomy, and a distal varisation and lengthening osteotomy, utilizing the Ilizarov external fixator in 14 (12 women) patients having a mean age of 20 (12-33) years. The most frequent preoperative complaints were pain, leg-length discrepancy, limping, reduced activity and limited abduction of the hip.

After an average follow-up of 68 (55-81) months, the outcome was satisfactory; pain subsided in all patients, the Trendelenburg sign became negative in all but 3 patients, no patient had limb-length discrepancy, and alignment of the extremity was reestablished. However, 3 patients still complained of lurch.  相似文献   
998.
The 575 inhabitants of the remote Anatolian village of Karain suffered 11 deaths from pleural mesothelioma in 1975/76 and there were five cases of fibrosing pleurisy. In the previous five years there had been 25 cases of mesothelioma. Calcified pleural plaques were common on survey radiography. Asbestos does not occur in the local soil or rock, nor is it handled in the village, but a few fibres were found in the water. Fibres were also found in the pleural tissue of two of five cases examined. Inhabitants of the neighbouring villages are free of mesothelioma.  相似文献   
999.
Malbora B  Senel E  Avci Z  Ozbek N 《Skinmed》2010,8(5):305-306
An 18-month-old boy was consulted to a pediatric clinic with a 5-month history of purpuric macules and nodules on the scalp. He had a history of trauma (falling down from a chair) to the scalp about 6 months before the consultation. He had been brought to an emergency department after the trauma. Cranial computed tomography revealed a small crack on the temporal bone. Purpuric macules and nodules of the scalp had been noticed on the control 1 month later. Results of total blood tests had been within normal limits. Dermatologic examination disclosed multiple pink to violaceous infiltrated cutaneous nodules and purpuric macules with diameters of0.5 to 1.5 cm on his scalp (Figure 1). No petechiae or ecchymoses were seen. Cervical lymphadenopathy was detected during physical examination. There was no hepatosplenomegaly. A punch biopsy was obtained from one of the infiltrated nodules and was sent for histopathologic examination. Histopathologic examination revealed diffuse dermal and subcutaneous edema, erythrocyte extravasation and infiltration by monomorphic cells with large hyperchromatic nuclei, and high mitotic activity (Figure 2). Histopathologic staining was positive for leukocyte common antigen and CD68 in these cells. Results of complete blood cell count of the patient were as follows: hemoglobin: 8.44 g/dL; white blood cell count: 29.2 x 10(9)/L; and platelet count 55.6 x 10(9)/L. Bone marrow aspirate results showed 68.4% blast cells and a biopsy specimen confirmed the diagnosis of acute myeloid leukemia, with flow cytometry findings positive for acute monoblastic leukemia (AML) French-American-British (FAB)-M5 phenotype. We initiated induction chemotherapy for AML (AML-M5) according to the AML Berlin-Frankfurt-Munster 2004 protocol.' Complete resolution of the leukemia cutis lesions was attained with chemotherapy at the end of the first month of treatment.  相似文献   
1000.
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