排序方式: 共有63条查询结果,搜索用时 15 毫秒
31.
Alberto Bargiotti Giuseppe Cassinelli Sergio Penco Aristide Vigevani Federico Arcamone 《Carbohydrate research》1982,100(1):273-281
Addition of methylmagnesium iodide to methyl 2,3,6-trideoxy-3-trifluoro-acetamido-α-l-threo-hexopyranosid-4-ulose (3) gave methyl 2,3,6-trideoxy-4-C-methyl-3-trifluoroacetamido-α-l-lyxo-hexopyranoside (4) and its l-arabino analogue, depending upon the reaction temperature and the solvent. The corresponding 4-O-methyl derivatives were obtained by treatment of 4 and 5 with diazomethane in the presence of boron trifluoride etherate. Treatment of 4 with thionyl chloride, followed by an alkaline work-up, gave methyl, 2,3,4,6-tetradeoxy-4-C-methylene-3-trifluoro-acetamido-α-l-threo-hexopyranoside (8), which was stereoselectively reduced to methyl 2,3,4,6-tetradeoxy-4-C-methyl-3-trifluoroacetamido-α-l-arabino-hexopyranoside. Epoxidation of 8 with 3-chloroperoxybenzoic acid gave the corresponding 4,41-anhydro-4-C-hydroxymethyl-l-lyxo derivative (10), which was also prepared by treatment of 3 with diazomethane. Azidolysis of 10, followed by catalytic hydrogenation and N-trifluoroacetylation, gave methyl 2,3,6-trideoxy-3-trifuloroacetamido-4-C-trifluoroacetamidomethyl-α-l-lyxo-hexopyranoside. 相似文献
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Michela Balsamo Leonardo Carlucci Maria Rita Sergi Karla Klein Murdock Aristide Saggino 《PloS one》2015,10(10)
Research on co-rumination has investigated its relationship with internalizing symptoms, but few studies have addressed underlying maladaptive cognitive-affective processes that may play an important role in the maintenance of this relation. This study examines if Young’s schema domains mediate the relation between co-rumination and depression in a community sample of non-clinical young adults. Participants completed the Co-Rumination Questionnaire, Young Schema Questionnaire-L3, and Teate Depression Inventory. Correlations and path analysis were calculated for the full sample and separately by gender. The schema domains of Overvigilance/Inhibition and Other-Directedness fully mediated the relation between co-rumination and depression. When analyses were performed separately for males and females, mediation persisted only for females. Findings suggest that among young women, co-rumination with a friend may be associated with depressive symptoms because of its activation of specific maladaptive cognitive schemas. Better understanding of the content and processes underpinning co-rumination may have important implications for the prevention and treatment of depression. 相似文献
33.
Fasnéwindé Aristide Kabore Papa Ahmed Fall Babacar Diao Boubacar Fall Anani Odzegbe Yahya Ould Tfeil Baye Assane Diagne 《Andrologie》2008,18(3):224-226
Penile amputation is a rare form trauma, usually occurring in psychotic patients, mostly with a diagnosis of schizophrenia. The management of self-mutilation of the genitalia is primarily psychiatric, designed to ensure acceptance of surgical repair by the patient. 相似文献
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Ribeiro L Andreazza AC Salvador M da Silveira TR Vieira S Nora DB Bosa C Di Napoli F Schaf DV Souza DO Portela LV Kapczinski F 《Neurochemical research》2007,32(9):1600-1603
Cirrhosis represents the terminal stage of a number of chronic liver diseases. Consequences include accumulation of toxic
metabolic wastes, reduced synthesis of key proteins, increased portal venous pressure, and portosystemic shunting. We conducted
a case-control study to assess the serum levels of S100B protein and parameters of oxidative stress, superoxide dismutase
(SOD), catalase (CAT) and oxidative stress measured by the thiobarbituric acid method (TBARS), in a group of 14 pediatric
patients with cirrhosis. No differences were found between groups in S100B protein levels. SOD activity and TBARS levels were
higher; and CAT activity was lower in the cirrhotic group. A negative correlation between S100B and TBARS in the case group
was found (r = −0.815, p = 0.001). Conclusions: This study didn’t indicate a possible role of S100B serum levels as marker of brain damage in cirrhotic children but suggest
a possible relation between astrocyte function and oxidative damage in cirrhotic children. 相似文献
38.
Wansi JD Lallemand MC Chiozem DD Toze FA Mbaze LM Naharkhan S Iqbal MC Tillequin F Wandji J Fomum ZT 《Phytochemistry》2007,68(15):2096-2100
The CH(2)Cl(2)/CH(3)OH (1/1) extract of the dried stem bark of Terminalia superba afforded two compounds, (7S,8R,7'R,8'S)-4'-hydroxy-4-methoxy-7,7'-epoxylignan and meso-(rel 7S,8R,7'R,8'S)-4,4'-dimethoxy-7,7'-epoxylignan along with 11 known compounds. The structures of the compounds were established by analysing the spectroscopic data and also comparing it with the data of previously known analogues. All the isolated compounds were evaluated for their glycosidase inhibition activities. Gallic acid and methyl gallate showed significant alpha-glucosidase inhibition activity. 相似文献
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Competition can drive macroevolutionary change, for example during adaptive radiations. However, we still lack a clear understanding of how it shapes diversification processes and patterns. To better understand the macroevolutionary consequences of competition, as well as the signal left on phylogenetic data, we developed a model linking trait evolution and species diversification in an ecological context. We find four main results: first, competition spurs trait diversity but not necessarily species richness; second, competition produces slowdowns in species diversification even in the absence of explicit ecological limits, but not in phenotypic diversification even in the presence of such limits; third, early burst patterns do not provide a reliable way of testing for adaptive radiations; and fourth, looking for phylogenetic signal in trait data and support for phenotypic models incorporating competition is a better alternative. Our results clarify the macroevolutionary consequences of competition and could help design more powerful tests of adaptive radiations in nature. 相似文献
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Thomas Druetz Federica Fregonese Aristide Bado Tieba Millogo Seni Kouanda Souleymane Diabaté Slim Haddad 《PloS one》2015,10(10)