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121.
Independent rankings of humor and aggressiveness were obtained for sets of cartoons drawn randomly from 2 magazines. The correlation of median humor and median aggressiveness rankings ranged from .49 to .90 in 6 studies involving 6 sets of cartoons and 6 different groups of Ss, including children and adults, high and low SES individuals, and native- and foreign-born Ss. It was found that this correlation was consistent with Freudian, arousal, and superiority theories of humor. Another prediction of Freudian theory, that high-SES Ss should be more appreciative of aggressive humor than low-SES Ss, was not supported. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
Investigated the perceptual functioning of individuals whose MMPI-168 profiles indicated schizophrenic tendencies but who did not exhibit marked thought disorder. The MMPI 2-7-8 code type was used to identify these 15 Ss from a pool of 909 college students. This group was compared on a backward visual masking task with 2 control groups: (a) 14 Ss whose profiles were inflation free and (b) 11 Ss whose profiles showed elevations on any 2 scales except the Sc. Critical interstimulus interval (ISI) was used as the dependent measure. The 2-7-8 group required significantly longer critical ISI to recognize target letters than did the inflation-free group. Regression analysis showed that for the group that showed inflations on any 2 scales except Sc, Sc was a significant predictor of critical ISI. It is concluded that a deficit exists at a very early stage in the visual information processing system of the 2-7-8 group. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
123.
The results of a comparative study of the effects of reinforcement on the stress fields in the critical intersection region of two normally intersecting cylindrical shells are presented. The results for in-plane and out-of-plane moments have been obtained experimentally by the use of electrical resistance foil gages, and numerically by the use of a three-dimensional finite element program. The finite element analysis also includes internal pressure loading. A comparison of results obtained by using a thin shell element with six degrees of freedom at each of the four nodes (three displacements and three rotations) and a three-dimensional element with three displacement degrees of freedom at each of the eight nodes, is also given.  相似文献   
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This study compared co-amoxiclav, vancomycin and teicoplanin with and without netilmicin or amikacin for treating experimental subcutaneous fibrin-clot infection in rabbits due to a clinical beta-lactamase-positive methicillin- and gentamicin-resistant Staphylococcus epidermidis strain (MGRSE). MICs (mg/L) for this strain were: oxacillin 125, gentamicin 32, vancomycin 4, teicoplanin 8, netilmicin 1, amikacin 4, amoxycillin 64 with clavulanate at 2 mg/L. In rabbits treated with a single-dose i.v. regimen (netilmicin 8 mg/kg, amikacin 20 mg/kg, vancomycin 30 mg/kg, teicoplanin 15 mg/kg, co-amoxiclav 150-30 mg/kg), the bacterial count 24 h post-dose was reduced whatever the combination used (ANOVA, P < or = 0.001). Regimens were statistically classified in decreasing order of efficacy as follows: co-amoxiclav combined with netilmicin > vancomycin either alone or combined with either netilmicin or amikacin, teicoplanin with netilmicin > netilmicin and co-amoxiclav alone > teicoplanin or co-amoxiclav combined with amikacin, and teicoplanin alone > amikacin > no drug. From these findings, it is concluded that: co-amoxiclav could be useful for the treatment of beta-lactamase-positive and methicillin-resistant S. epidermidis infection; some enzyme-resistant aminoglycoside could be considered for treating gentamicin-resistant but netilmicin/amikacin-sensitive S. epidermidis infection; the combination of co-amoxiclav with netilmicin was synergistic and more rapidly bactericidal than vancomycin in this animal model.  相似文献   
126.
A new thermodynamic model for calculating the dissociation constants of complexes formed between the aryl hydrocarbon receptor (AhR) and polychlorinated biphenyls (PCBs) is reported. The free energies of binding of PCBs to AhR are controlled by their lipophilicities, electron affinities, and entropies. The corresponding physicochemical properties of polychlorinated dibenzo-p-dioxins and dibenzofurans also control their interactions with AhR. We present evidence supporting the hypothesis that the majority of PCBs are likely to interact with AhR in their nonplanar conformations. In addition, we demonstrate that the affinities of PCBs for AhR relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin correlate with corresponding toxic equivalency factors in animals. The reported methodology is likely to be applicable to other polyhalogenated and mixed polyhalogenated bi- and terphenyls and related xenobiotics; thus, it could minimize the number of in vivo studies in laboratory animals and facilitate the identification of potentially hazardous aromatic xenobiotics.  相似文献   
127.
Phosphatidylinositol 4,5-bisphosphate (PIP2) is involved in the organization of the actin cytoskeleton by regulating actin-associated proteins. The transmembrane heparan sulfate proteoglycan syndecan-4 also plays a critical role in protein kinase C (PKC) signaling in the formation of focal adhesions and actin stress fibers. The cytoplasmic domain of syndecan-4 core protein directly interacts with and potentiates PKCalpha activity, and it can directly interact with the phos- phoinositide PIP2. We, therefore, investigated whether the interaction of inositol phosphates and inositol phospholipids with syndecan-4 could regulate PKC activity. Data from in vitro kinase assays using purified PKCalpha beta gamma show that in the absence of phosphatidylserine and diolein, PIP2 increased the extent of autophosphorylation of PKCalpha beta gamma and partially activated it to phosphorylate both histone III-S and an epidermal growth factor receptor peptide. This activity was dose-dependent, and its calcium dependence varied with PKC isotype/source. Addition of the cytoplasmic syndecan-4 peptide, but not equivalent syndecan-1 or syndecan-2 peptides, potentiated the partial activation of PKCalpha beta gamma by PIP2, resulting in activity greater than that observed with phosphatidylserine, diolein, and calcium. This study indicates that syndecan-4 cytoplasmic domain may bind both PIP2 and PKCalpha, localize them to forming focal adhesions, and potentiate PKCalpha activity there.  相似文献   
128.
An improved lithium acetate (LiAc)/single-stranded DNA (SS-DNA)/polyethylene glycol (PEG) protocol which yields >1 × 106 transformants/μg plasmid DNA and the original protocol described by Schiestl and Gietz (1989) were used to investigate aspects of the mechanism of LiAc/SS-DNA/PEG transformation. The highest transformation efficiency was observed when 1 × 108 cells were transformed with 100 ng plasmid DNA in the presence of 50 μg SS carrier DNA. The yield of transformants increased linearly up to 5 μg plasmid per transformation. A 20-min heat shock at 42°C was necessary for maximal yields. PEG was found to deposit both carrier DNA and plasmid DNA onto cells. SS carrier DNA bound more effectively to the cells and caused tighter binding of 32P-labelled plasmid DNA than did double-stranded (DS) carrier. The LiAc/SS-DNA/PEG transformation method did not result in cell fusion. DS carrier DNA competed with DS vector DNA in the transformation reaction. SS plasmid DNA transformed cells poorly in combination with both SS and DS carrier DNA. The LiAc/SS-DNA/PEG method was shown to be more effective than other treatments known to make cells transformable. A model for the mechanism of transformation by the LiAc/SS-DNA/PEG method is discussed.  相似文献   
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