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41.
The "direct-on-barrier" electroplating of copper on ruthenium from a 1 mol dm−3 solution of CuCl in the ionic liquid 1-ethyl-3-methylimidazolium dicyanamide, [C2mim][N(CN)2], is reported. Continuous layers of copper with a preferential Cu(111) orientation were obtained from this electrolyte. The copper coatings were investigated by top view scanning electron microscopy (SEM), X-ray diffraction (XRD), and focused ion beam transmission electron microscopy (FIB-TEM). The nucleation density was both theoretically and experimentally evaluated by the Scharifker-Hills model and transmission electron microscopy, respectively. The direct plating of copper on resistive substrates for advanced interconnects and package is a promising new application of ionic liquids.  相似文献   
42.
Lipopolysaccharides released during bacterial infections induce the expression of pro-inflammatory cytokines and lead to complications such as neuronal damage in the CNS and septic shock in the periphery. While the initial infection is treated by antibiotics, anti-inflammatory agents would be advantageous add-on medications. In order to identify such compounds, we have compared 29 commercially available polyphenol-containing plant extracts and pure compounds for their ability to prevent LPS-induced up-regulation of NO production. Among the botanical extracts, bearberry and grape seed were the most active preparations, exhibiting IC(50) values of around 20 mug/mL. Among the pure compounds, IC(50) values for apigenin, diosmetin and silybin were 15, 19 and 12 muM, in N-11 murine microglia, and 7, 16 and 25 muM, in RAW 264.7 murine macrophages, respectively. In addition, these flavonoids were also able to down-regulate LPS-induced tumour necrosis factor production. Structure-activity relationships of the flavonoids demonstrated three distinct principles: (i) flavonoid-aglycons are more potent than the corresponding glycosides, (ii) flavonoids with a 4'-OH substitution in the B-ring are more potent than those with a 3'-OH-4'-methoxy substitution, (iii) flavonoids of the flavone type (with a C2=C3 double bond) are more potent than those of the flavanone type (with a at C2-C3 single bond).  相似文献   
43.
Leydig cell function in mice lacking connexin43   总被引:1,自引:0,他引:1  
Connexin43 (Cx43) is the most abundantly expressed member of the connexin (gap junction protein) family and the only one so far identified in mouse Leydig cell gap junctions. Mice lacking Cx43 were used to investigate its role in testicular androgen production and regulation. Testes from term fetuses were grafted under the kidney capsules of castrated adult males. After 3 weeks, serum from host mice was analyzed for androgens. In order to test their response to stimulation, the grafted testes were incubated in vitro with varying concentrations of LH and their androgen end products analyzed. Incubation with radiolabeled progesterone was followed by high performance liquid chromatography to quantify the androgen-intermediate metabolites. Radiolabeled testosterone in the presence of NADPH was used to determine the activity of testosterone-metabolizing enzymes 17beta-hydroxysteroid dehydrogenase (17betaHSD), 5alpha-reductase (5alphaR), and 3alpha-hydroxysteroid dehydrogenase (3alpha HSD). Serum androgen levels did not differ between hosts carrying wild-type versus null mutant grafts although Cx43-deficient testes had more 17betaHSD and 5alphaR activity than wild-type controls. Furthermore, the genotype of grafted testes did not influence LH-stimulated androgen production in vitro. These results indicate that the steroidogenic function of Leydig cells is not compromised by the absence of Cx43, perhaps because other gap junction proteins are present. Dye transfer experiments demonstrated that Cx43-deficient Leydig cells retain intercellular coupling, indicating that Cx43 is not the only protein contributing to their gap junctions. Thus, despite their prominence in Leydig cells, Cx43 gap junctions are not essential for androgen production.  相似文献   
44.
 Bisphenol A diglycidyl ether (BADGE) is determined in canned oily foods from Austria using a new simplified HPLC method. Samples are extracted with pentane, back extracted with methanol, and finally dissolved in the mobile phase (cyclohexane/tert–butyl methyl ether). Separation is performed on a normal-phase HPLC column using fluorescence detection. Verification of the BADGE-containing peak is carried out by using off-line GC-MS. Additionally, the synthesis and determination of BADGE hydrolysis products, Bisphenol A bis(2,3-dihydroxypropyl) ether (BADGE.2H2O) and Bisphenol A glycidyl (2,3-dihydroxypropyl) ether (BADGE.H2O) are presented. From 67 analyzed cans, containing various fatty meat or fish products, 16% were above the maximum quantity of 1 mg/kg tolerated by the European Community, 45% were in the range between 0.1–1 mg/kg, 24% between 0.02 and 0.1 mg/kg, and in 15% the BADGE concentrations were below the detection limit of 0.02 mg/kg. The hydrolysis product BADGE.H2O was not detected in any sample, whereas BADGE.2H2O was found in some samples up to a concentration of 0.5 mg/kg. Received: 11 May 1998 / Revised version: 1 July 1998  相似文献   
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Discusses G. M. Rosen's (see record 1975-31957-001) suggestion that associative homogeneity, as described by L. J. and J. P. Chapman (see record 1969-13004-001), may influence the persistence of illusory correlations. It is pointed out, however, that Rosen's suggestion should not be confused with issues of causality raised in the Chapmans' article. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
48.
Asserts that in preparing objectives of television programming for children the instructor must (a) recognize the needs and interests of his/her audience and (b) match them to his/her educational purposes. The techniques used to identify and implement methods of attaining the goals of the television programs "Sesame Street" and "The Electric Company" are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
Two studies investigated the reliability and validity of a new behavioral rating scale, the Verbal Report Form (VRF), which measures brief unstructured verbal interactions of chronic mental patients. In Study 1, 6 individuals familiar with the VRF rated 12 videotaped segments (differing in length) of chronic schizophrenic patients. Results indicate that a 2-min time segment was necessary to accurately assess conversational behavior (mean rater agreement = .76). In Study 2, 15 raters (5 psychologists, 5 psychiatric technicians, and 5 nonprofessionals) rated 15 2-min video-tapes of verbal behavior (5 hospitalized patients, 5 board and care residents, and 5 normals). Results of an analysis of variance suggest that the VRF could significantly discriminate among the 3 contrasting groups using the number of inappropriate responses rated. Results are discussed in terms of differences between raters and difference in the discriminability of the categories of the VRF. (1 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
Examined the effects of instructions and modeling in the reflection-of-feeling training of individuals low in interpersonal-communication skills. Participants with low scores on R. Carkhuff's Communication Index (25 males and 25 females) were randomly assigned by sex to 1 of the 5 training groups so that there were 5 males and 5 females in each group. After viewing videotaped training material, each participant conducted a 15-min interview with a volunteer "client" and completed the Communication Index a second time. Interviews were scored for frequency of reflection-of-feeling responses and level of empathic communication displayed. Analysis of the reflection-of-feeling data indicated that instructions and instructions-plus-modeling were facilitative procedures. Ratings of written and verbal empathy demonstrated the effectiveness of the 2 combined conditions: instructions-plus-modeling and modeling-plus-instructions. Calculation of correlations among scores on criterion measures revealed a positive correlation between reflection-of-feeling scores and ratings of empathic communication. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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