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Context: The widespread use of Pistacia atlantica Desf. ssp. (Anacardiaceae) in traditional medicine can be partly attributed to the content of its secondary metabolites, in particular, the phenolic compounds.

Objective: The effects of harvest period, growing region and gender on the phenolic compounds, flavonoids and condensed tannins contents were studied, as well as on the antioxidant activities of P. atlantica leaves in order to provide a scientific basis for optimal collection.

Materials and methods: Leaves were collected monthly from April to October 2010 in two Algerian sites. The powdered leaves were used for preparing the ethyl acetate extract. Contents of total phenolics (TPC), flavonoids (FC) and condensed tannins (CTC) were determined spectrophotometrically. Antioxidant activity was evaluated through radical scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (250?μM) and the reducing power capacity (RPC) determination by K3Fe(CN)6 (1%).

Results: The TPC was found to vary from 79?±?13 to 259?±?8?mg gallic acid equivalents/g of dry weight (DW) during the study period. The RSA and RPC varied between 262?±?18 and 675?±?21?mg Ascorbic Acid Equivalent (AAE)/g DW, and from 259?±?16 to 983?±?20?mg AAE/g DW, respectively. A seasonal pattern was observed consisting of a decrease in TPC content and RPC from spring to autumn. The FC, CTC and RSA did not show a seasonal pattern.

Discussion and conclusion: Our findings showed that secondary metabolite content and antioxidant activities of P. atlantica leaves were more influenced by harvest time and growing region than by gender.  相似文献   
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Sevoflurane is thought to have a potential for hepatotoxicity. A few cases of hepatotoxicity have been reported since it was introduced in 1990 into clinical practice in Japan. The underlying pathophysiology of hepatotoxicity is nonspecific. We report a case of severe hepatic dysfunction after uneventful sevoflurane anesthesia in a child with posterior fossa resection of medulloblastoma. The case of sevoflurane being incriminated is unclear due to various confounding factors that is worthy of discussion.  相似文献   
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Conduction abnormalities and arrhythmias may occur in patients following secundum atrial septal defect (ASD) closure using the Amplatzer® septal occluder (ASO). Therefore, the aim of this study was to prospectively perform ambulatory ECG monitoring to assess the electrocardiographic effects of transcatheter closure (TCC) of ASD using the ASO device.From 5/97 to 3/99, 41 patients with secundum ASD, underwent TCC using the ASO device at a median age of 9.2[emsp4 ]y. (0.5–87[emsp4 ]y.) and median weight of 34[emsp4 ]kg (5.6–88[emsp4 ]kg.). Ambulatory Holter monitoring was performed pre- and immediately post TCC. Holter analysis included heart rate (HR), ECG intervals, supraventricular ectopy (SVE), ventricular ectopy (VE), and AV block.No change in baseline rhythm was noted in 37 patients (90%). Changes in AV conduction occurred in 3 patients (7%), including intermittent second degree AV block type II, and complete AV dissociation post closure. SVE was noted in 26 patients (63%) post closure, ranging from 5–2207 supraventricular premature beats (SVPB), including 9 patients (23%) with non-sustained supraventricular tachycardia (SVT), 3 of whom had short runs of SVT prior to closure. A significant increase in post-closure number of SVPB per hour (p=0.047) was noted. No significant difference was noted in PR interval, ventricular premature beats per hour, or QRS duration. Conclusions: Based on ambulatory ECG analysis, TCC of ASD with the ASO device is associated with an acute increase in SVE and a small risk of AV conduction abnormalities, including complete heart block. Long term follow-up studies will be necessary to determine late arrhythmia prevalence and relative frequency compared with standard surgical ASD repair.  相似文献   
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