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In the case of water soluble polymers, the use of size exclusion chromatography (SEC) for the determination of the molecular weight involves numerous difficulties. In order to analyse and determine the molecular weight of acrylic acid telomers we have first tried to obtain a satisfactory and reproducible separation. In this particular case, low-molecular-weight standards are not commercially available. Therefore, we decided to prepare standards based on acrylic acid, either by telomerization with a fluorinated telogen or by polymerization with an initiator bearing a fluorinated group. A calibration curve was obtained from the standards. Telomers of acrylic acid with thioglycolic acid were analysed. This is a general method for determination of DP n by SEC when there is no standard for the polymers. It can be used in a wide range of DP n from 1 to 700.  相似文献   
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The opening in the intra hepatic bile ducts is the most common complication of hepatic hydatid cyst. The opening in the gallbladder is unusual.We report the case of a 65-year-old woman with complaints of right upper quadrant pain and fever. Various explorations have found a hydatid acute cholecystitis due to an opening of a hydatid cyst of the liver in the gallbladder. Treatment was surgical.  相似文献   
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Hydatidiform moles (HM) are characterized by an abnormal proliferating trophoblast with a potential for a malignant transformation. Similar to other human tumors, trophoblastic pathogenesis is likely a multistep process involving several molecular and genetic alterations. The study was performed to investigate the expression patterns of c-erbB-2 and Bcl-2 oncoproteins, p53, p21WAF1/CIP1 and p63 tumor suppressor proteins and Ki-67 cell proliferation marker in HM.We conducted a retrospective study of 220 gestational products, including 39 hydropic abortions (HA), 41 partial HM (PHM) and 140 complete HM (CHM). The expression of c-erbB-2, Bcl-2, p53, p21WAF1/CIP1, p63 and Ki-67 was investigated by immunohistochemistry on archival tissues. c-erbB-2 expression was observed in three PHM and 10 CHM. Bcl-2 immunostaining was significantly higher in PHM (61%) and CHM (70.7%) compared with HA (7.7%, p?=? 0.001 and p?<? 0.0001, respectively). p53 expression was stronger in CHM (73.6%) compared with PHM (24.4%, p < 0.0001) and HA (12.8%, p < 0.0001). p21WAF1/CIP1 staining was observed as well in molar and non-molar gestations (p?>? 0.05). p63 immunoexpression was significantly described in CHM (85.7%) and PHM (78%) compared with HA (10.2%, p < 0.0001 and p = 0.0001, respectively). Ki-67 was significantly expressed in CHM (72.1%) compared with HA (46.2%, p = 0.005).Altered expression of Bcl-2, p53, p63 and Ki-67 reflects the HM pathological development. Immunohistochemical analysis is beneficial to recognize the HM molecular and pathogenic mechanisms. Furthermore, it could serve as a useful adjunct to conventional methods for refining HM diagnosis.  相似文献   
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Micronutrients as well as essential fatty acids are indispensable for the correct functioning of the organism. The risk of disturbance in the associated nutrition and metabolism is expected to increase during ageing. In addition, it seems that trace elements are involved in the fatty acids metabolism. The aim of the present study was then to assess age-related changes in trace elements status and in plasma essential fatty acids composition with an emphasis on the desaturase activity estimation. Two hundred healthy Tunisian subjects (30-85 years old) were recruited and separated into two subgroups: elderly (65-85 years old) and middle-aged (30-60 years old). The findings revealed that plasma zinc and calcium concentrations significantly decreased according to age. The prevalence of zinc deficiency was therefore shown to increase in old age (over 60% of elderly subjects were deficient or at risk of deficiency). No age-related changes were obtained for copper or magnesium status. The Δ6 desaturase, involved in the EFAs conversion, was shown to decrease according to age and to be associated with the plasma zinc level. Since elderly subjects were at risk of nutritional imbalance, it would be interesting to set optimal dietary proportion. This will help to prevent age-associated alterations and diseases for a better and healthy ageing.  相似文献   
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The purpose of this article is to overview vector-borne rickettsioses in North Africa, focusing on epidemiologic aspects, clinical features, diagnosis procedures, and treatment. The protective measures, the exposure to risk, and the dynamics of endemic emerging and re-emerging diseases in the region are detailed to minimize the risk when traveling in this area. In addition, the article describes the scientific contribution on the rickettsial field of North-African researchers from the beginning of the 20th century until today.  相似文献   
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PHACES syndrome consists of the constellation of manifestations including posterior fossa anomalies of the brain (most commonly Dandy-Walker malformations), hemangiomas of the face and scalp, arterial abnormalities, cardiac defects, eye anomalies and sternal defects. We present a case with a possible PHACES syndrome including sternal cleft and supraumbilical raphé, precordial skin tag, persistent left superior vena cava and subtle narrowing of the aorta with an endobronchial carcinoid tumor. All these anomalies were discovered on chest multi-detector CT. This is a unique case of PHACES syndrome associated with carcinoid tumor. Review of the literature revealed 3 cases of PHACES syndrome with glial tumor. The authors tried to find the relationship between PHACES syndrome and carcinoid tumors or gliomas, which all derive from the neural crest cells.  相似文献   
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