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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   
895.
BACKGROUND AND STUDY AIMS: Anastomotic leakage is a severe complication in gastric surgery and it is associated with a high rate of mortality. Conservative treatment sometimes is not sufficient to stem the leakages and, even when it is sufficient, it takes a long time. The present study describes the first experience in the treatment of anastomotic leakages with endoscopic clipping. PATIENTS AND METHODS: From May 1995 to December 1996, seven patients with postoperative anastomotic leakages after gastric surgery were prospectively treated in our Endoscopy Service. Metallic endoclips (MD 850, Olympus Corp., Tokyo, Japan) with prongs 12 mm long and 6 mm wide were applied, controlling the closure of the leakage by endoscopy, using radiographs to confirm the closure 24 hours later. RESULTS: Complete closure of the leakage was obtained in all seven cases. A single session of endoscopic clipping was needed for five patients while two other required, respectively, two and three sessions. The median time of leakage closure after endoscopic clipping was 2.3 days (range 1-5 days). The clips spontaneously dislodged within 1 month in five patients and within the second month in the other two patients. CONCLUSION: Endoscopic treatment of anastomotic leakages by metallic clips represents a safe and easily repeated method and, compared to conservative treatment, it seems to offer several time and cost advantages. Further studies involving a larger number of patients are needed to verify this finding.  相似文献   
896.
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   
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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   
899.
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   
900.
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   
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