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871.
872.
In 7 experiments the authors investigated the locus of word frequency effects in speech production. Exp 1 demonstrated a frequency effect in picture naming that was robust over repetitions. Exps 2, 3, and 7 excluded contributions from object identification and initiation of articulation. Exps 4 and 5 investigated whether the effect arises in accessing the syntactic word (lemma) by using a grammatical gender decision task. Although a frequency effect was found, it dissipated under repeated access to a word's gender. Exp 6 tested whether the robust frequency effect arises in accessing the phonological form (lexeme) by having Ss translate words that produced homophones. Low-frequent homophones behaved like high-frequent controls, inheriting the accessing speed of their high-frequent homophone twins. Because homophones share the lexeme, not the lemma, this suggests a lexeme-level origin of the robust effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
873.
874.
To determine whether a structural defect in glucokinase could be a primary cause of glucose intolerance in the common form of NIDDM, the prevalence of mutations in the gene in 60 American black NIDDM patients was investigated. First, by Southern blot analysis of DNA from a subset of randomly selected subjects (n = 20), no gross deletions, insertions, or rearrangements of the gene were detected. Next, the 5'-untranslated and coding regions of the gene were amplified directly from genomic DNA by the polymerase chain reaction. PCR products were screened for mutations by using single-strand conformational polymorphism analysis. A total of nine variants were identified, with two in the 5'-UT regions of islet exon 1, two in the 5'-UT region of liver exon 1, and five in the coding regions. For islet exon 1, 5 of 60 NIDDM patients had both variants in the 5'-UT region; and for liver exon 1, two variants each occurred in 1 of 60 NIDDM patients. The coding region variants included a missense mutation in islet exon 1, substitution of Ala11 (GCC) with Thr11 (ACC), found in 2 patients. The biological consequences of this mutation and the mutations in the 5'-UT portion of the gene have yet to be determined. The rest of the variants were third base pair changes of codons, i.e., silent. A common polymorphism, which was in linkage equilibrium with microsatellite repeats GCK1 and GCK2, was found in intron 9, and a variant in intron 2 in both alleles of 1 patient.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
875.
B H?rning 《Canadian Metallurgical Quarterly》1998,105(8):313-321
Intensive animal husbandry is criticized in relation to the fulfillment of the animals needs. The guidelines of the organizations of organic agriculture offer the opportunity for better animal welfare. In this paper an overview is given concerning animal health and welfare on organic farms with dairy cows, fattening pigs and laying hens. On organic farms housing systems with the potential for a better animal welfare dominate. In field studies using scoring systems (animal welfare index) organic farms reach more points than conventional ones. However, animal health on average is not much better on organic farms. The health problems discussed in the paper are mainly caused by management problems. Therefore, improvements are possible. 相似文献
876.
LS H?varstein 《Canadian Metallurgical Quarterly》1998,6(8):297-9; discussion 299-300
877.
RM Hendry CV Hanson V Bongertz M Morgado A Duarte J Casseb L Brigido E Sabino R Diaz B Galv?o-Castro 《Canadian Metallurgical Quarterly》1996,91(3):347-348
The influence of noncompetitive (MK-801), competitive (AP-7) and the antagonist of polyamines site of NMDA receptor (arcaine) on the central activity of angiotensin II (A II) was studied. The open field test, conditioning of active avoidance responses (CARs) and passive avoidance situation was used to investigate learning and memory in rats. All used antagonists decreased beneficial action of A II on these processes. 相似文献
878.
J G?uszek B Raszeja-Wanic I Stachowiak F Banaszak L Szcze?niak D Musialik T Kosicka A Tykarski A Boruczkowska A Sko?uda A Ma?aczyńska A Wichrowska K Rutz-Danielczak B Krasińska 《Canadian Metallurgical Quarterly》1996,96(6):570-576
Two groups of hypertensive patients: 137 responsive (on one or two drugs) and 162 resistant on antihypertensive treatment in the similar age were compared. Resistant patients (on three or more drugs) characterize by significantly higher body weight and BMI, longer history of hypertension, more frequent hypertension prevalance in family members and lower education. Level of triglycerides in resistant on antihypertensive treatment patients was significantly higher than in responsive patients. Insulin level in blood in 31 patients with essential hypertension was significantly higher than in 36 healthy persons and 20 patients with renovascular hypertension and resistant on antihypertensive therapy. In 14 patients with essential hypertension resistant to treatment insulin level one hour after oral glucose load was significantly (p < 0.01) higher than in 16 patients with essential hypertension responsive to antihypertensive treatment. 相似文献
879.
J Bunikis L Noppa Y Ostberg AG Barbour S Bergstr?m 《Canadian Metallurgical Quarterly》1996,64(12):5111-5116
A chromosomally encoded 66-kDa protein (P66) of Borrelia spp. that cause Lyme disease has previously been shown to be associated with the spirochetal outer membrane. A topological model of P66 predicts a surface-exposed fragment which links the N- and C-terminal intramembranous domains of the protein (J. Bunikis, L. Noppa, and S. Bergstr?m, FEMS Microbiol. Lett. 131:139-145, 1995). In the present study, an immunogenic determinant of P66 was identified by a comparison of the immunoreactivities of different fragments of P66 generated either by proteolytic treatment of intact spirochetes or as recombinant proteins expressed in Escherichia coli. The immune response to P66 during natural infection was found to be directed against the predicted surface domain which comprises amino acids at positions 454 through 491. A sequence comparison revealed considerable polymorphism of the surface domains of P66 proteins of different Lyme disease-causing Borrelia species. Five sequence patterns of this domain were observed in the B. garinii strains studied. In contrast, sequences of the relevant part of P66 of the B. afzelii and B. burgdorferi sensu stricto isolates studied were identical within the respective species. In immunoblotting, 5 of 17 (29.4%) sera from North American patients with early disseminated or persistent Lyme disease reacted against P66 of B. burgdorferi sensu stricto B31. These sera, however, failed to recognize P66 of B. afzelii and B. garinii, as well as an analog of P66 in the relapsing fever agent, B. hermsii. In conclusion, the topological model of P66 is supported by the demonstration of an apparent surface localization of an immunoreactive domain of this protein. Furthermore, analogous to the plasmid-encoded borrelial outer surface proteins, the predicted surface-exposed portion of chromosomally encoded P66 appears to be antigenically heterogenous. 相似文献
880.
M Kester RJ Nowinski H Holth?fer PA Marsden MJ Dunn 《Canadian Metallurgical Quarterly》1994,46(5):1404-1412
Platelet-activating factor synthesis in two transformed lines of glomerular endothelial cells was characterized and contrasted with platelet-activating factor production in macrovascular-derived endothelial cells as well as with glomerular cells of mesenchymal origin. Platelet-activating factor synthesis was assessed in intact cells and in cell-free preparations. Glomerular endothelial cells constitutively synthesize bio-active alkyl-PAF, and this basal activity can be chronically augmented by various inflammatory and thrombotic agents. In contrast, thrombin-mediated platelet-activating factor formation in bovine pulmonary aortic endothelial cells as well as in glomerular mesangial cells is acute and transient. The potential role of anti-inflammatory prostanoids to function as negative feedback modulators of thrombin- or endothelin-mediated platelet-activating factor synthesis was also investigated, as the synthesis of platelet-activating factor is often associated with the formation of these prostanoids. Indomethacin augmented receptor-mediated platelet-activating factor synthesis while prostanoids of the E and I series reduced agonist-stimulated PAF synthesis. In summary, the unique capacity of glomerular endothelial cells to respond to inflammatory stimuli with sustained platelet-activating factor synthesis is a clear indication of this cell's pivotal role in augmenting the inflammatory response in the limited environment of the glomerulus. 相似文献