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31.
Amiodarone was injected endoneurially at increasing doses into the exposed tibial nerve of rats to study its electrophysiologic and pathologic effects on peripheral nerve fibers. Forty-five male Wistar rats were used, and each of the following concentrations was injected into 15 nerves: 25 micrograms/mL, 50 micrograms/mL, and 100 micrograms/mL. Microinjection of a 25 micrograms/mL concentration of amiodarone resulted in a subacute, incomplete conduction block evident at day 3 postinjection. This conduction block remained stable until day 10 and recovery was complete at day 35. Microinjection of a 50 micrograms/mL concentration of amiodarone produced a faster evolving conduction block, and significant axon degeneration (approximately 40% of fibers). Injection of a 100 micrograms/mL concentration resulted in severe acute motor axon degeneration followed by complete but delayed regeneration. Results of morphological studies closely correlated with electrophysiological findings. Amiodarone thus seems to have a direct toxic effect on axons at high concentrations in the peripheral nerve, and we suggest that different pathological changes described in human amiodarone neuropathy could be related to different concentrations of the drug in the nerve, perhaps due to variability of blood-nerve barrier efficacy.  相似文献   
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BACKGROUND: The addition of short course pre-operative radiotherapy to total mesorectal excision reduces local recurrence in resectable adenocarcinoma of the rectum. In a previous retrospective study potential factors associated with early complications following this combination were identified. The aim of this study was to examine these relationships in a prospective multicentre audit. METHODS: One hundred and seven patients who received short course pre-operative radiotherapy in four cancer centres between 1 October 2001 and 30 September 2002 were included. Data including patient age, radiotherapy field length, overall treatment time, operation type, surgical outcomes and complications occurring within 3 months of the 1st day of radiotherapy were collected. These were compared and combined with the previously studied cohort of 176 patients treated at one centre between 1st January 1998 and 31st December 1999. RESULTS: In the prospective cohort only patient age (P=0.001) was significantly associated with acute complications. However, both the overall treatment time (median 9.0 vs 11.0 days P <0.0001) and field length (median 16.6 vs 17.0 cm P=0.03) were significantly shorter in this cohort when compared to the previous retrospective study. In patients from both studies (n=283), increasing age (P=0.002) and field length (independent of operation type) (P=0.02) were independently associated with an increased risk of acute complications. CONCLUSIONS: This study suggests that meticulous selection of patients for short course pre-operative radiotherapy and smaller planning target volumes may be associated with a lower risk of acute complications. The use of MRI scanning to stage pelvic disease may reduce the number of patients with R1 resections receiving short course pre-operative radiotherapy.  相似文献   
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目的探讨十二指肠镜下逆行胆胰管造影(ERCP)及取石(EST)引发急性胰腺炎的防治方法。方法对该院已行ERCP和EST的42例患者的临床资料进行回顾性分析。结果6例术后并发急性胰腺炎,其中1例死亡。结论ERCP和EST引发急性胰腺炎,主要有两种情况,一是化学刺激引发急性胰腺炎;另一方面为共同通道受阻引发急性胰腺炎,只有在操作中认真防范,术后仔细观察、处理,该并发症是可以防治的。  相似文献   
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目的 探讨急性脑梗死 (ACI)诱发全身炎症反应综合征 (SIRS)致多器官功能障碍综合征(MODS)的发病机制 ,以及血清肿瘤坏死因子 (TNF α)、白细胞介素 (IL 1) β含量变化在ACI诱发SIRS发生、发展并向MODS转化的临床意义。方法  6 8例ACI患者根据病情变化分为 3组 ,其中单纯性ACI(SACI组 ) 36例 ,ACI致SIRS(SIRS组 ) 32例 ,ACI致SIRS后发展为MODS(MODS组 ) 2 4例 ;应用酶联免疫吸附法 (ELISA法 )分别测定患者不同病程中血清TNF α、IL 1β值 ,并与对照组 (为 2 8名同期健康体检者 )比较。 结果  (1) 6 8例ACI中 4 7.0 6 %发生SIRS;SIRS时 75 %发生MODS。 (2 )血清TNF α、IL 1β的含量MODS 组 >SIRS组 >SACI组 >对照组 ,各组间比较 ,差异具有极显著性 (均P <0 0 1)。MODS重症者 (积分≥ 9分 )血清TNF α、IL 1β含量高于轻症者 (积分 <9分 ) (均P <0 0 1) ;MODS死亡者血清TNF α、IL 1β含量高于存活者 (均 P <0 0 1)。结论  (1)ACI后出现SIRS可导致MODS的发生。 (2 )患者血清TNF α、IL 1β水平异常变化可作为判断ACI致SIRS、MODS病情进展、预后及转归的一项指标  相似文献   
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Changing perspectives in 95 children with poststreptococcal acute glomerulonephritis (PSAGN) in our hospital between 1979 and 1988 are reported. Between 1961 and 1970 an average of 31±6.3 patients/year with PSAGN were treated and 70% had antecedent pyoderma. In the present study antecedent pharyngitis was observed in 59 children und pyoderma in 36. In comparison to the decade ending in 1970 our data show: (1) a marked decline in the prevalence of PSAGN (P=<0.0005), (2) a predominance of antecedent pharyngeal infection (P=0.044), (3) a decline in urban and an increase in rural patients with PSAGN (P=0.0483); and in the last decade: (1) a predominance of antecedent pharyngeal infection in children over 6 years of age (P=0.0009) and (2) a predominance of antecedent pyoderma in black children (P=0.0004).  相似文献   
39.
Abstract: Blast cells derived from peripheral blood of patients with acute myelogenous leukaemia (AML) were cultured in vitro and interleukin 1 receptor antagonist (IL1RA) concentrations determined in culture supernatants. AML blasts derived from patients classified as AML-M4 and AML-M5 subtype showed an increased release of IL1RA. IL1α and IL1β caused a similar increase in AML blast release of IL1RA, and addition of anti-ILl antibodies decreased IL1RA release. IL1RA release from AML blasts was also increased by stem cell factor, tumour necrosis factor α (TNFα), granulocyte-macrophage colony-stimulating factor and macrophage colony-stimulating factor, whereas interleukin 3, interleukin 6, leukaemia inhibitory factor and granulocyte colony- stimulating factor did not significantly alter IL1RA release. When investigating IL1RA serum levels, serum concentrations were decreased in acute leukaemia patients with chemotherapy-induced cytopenia compared with healthy controls. Serum levels of both IL1RA as well as IL1β and soluble TNFα receptors increased when the leucopenic patients developed complicating bacterial infections.  相似文献   
40.
Equating the condition after cardiac arrest with that of medial temporal damage, and consequently medial temporal lobe amnesia, is questioned on the basis of results from a patient who was studied neuropsychologically as well as with static and dynamic imaging methods (MRI, PET) 6–9 months after a heart attack. The patient manifested severe and persistent anterograde and retrograde amnesia, as well as further cognitive deteriorations. While MRI only indicated non-specific cortical atrophy, PET revealed a severe bilateral affection of the thalamus and of both medial and lateral temporal cortices as well as occipito-parietal hypometabolism. The neuropsychological status indicates that patients with a diagnosis of cardiac arrest may suffer very severe and persistent cognitive deficits; the imaging analyses show that cardiac arrests may lead to quite severe and widespread brain damage which, however, may not be visible with current magnetic resonance imaging technology, but which is clearly apparent from positron emission tomography. These data suggest that patients with a condition after a heart attack may not be valid models for pure hippocampal—or even medial temporal lobe—pathology, as they may suffer much more widespread brain damage.  相似文献   
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