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71.
OBJECTIVE: Schizophrenic patients typically perform poorly on the Wisconsin Card Sorting Test, which is a putative index of prefrontal functioning. The authors attempted to remediate the deficits of schizophrenic patients on this measure by giving detailed instructions and monetary reinforcement. METHOD: Forty-six inpatients with chronic schizophrenia and 20 control subjects with other psychiatric illnesses were given the Wisconsin Card Sorting Test under four conditions that varied in monetary reinforcement and level of instructions. The schizophrenic patients were given the Brief Psychiatric Rating Scale (BPRS) and three information processing measures (the Continuous Performance Test, Span of Apprehension, and Pin Test). RESULTS: Schizophrenic patients performed worse than psychiatric control subjects across most conditions. Monetary reinforcement had little effect on performance, but detailed instructions significantly improved the scores for both groups. When instructions were withdrawn and monetary reinforcement was maintained, both groups continued to show improved performance over baseline. Symptoms were not significantly associated with Wisconsin Card Sorting Test performance. One measure (the Pin Test) correlated significantly with performance on the Wisconsin Card Sorting Test. CONCLUSIONS: The results suggest the importance of combining motivational with instructional factors for training psychiatric patients in problem solving. 相似文献
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Jeremy Green 《Developmental dynamics》2002,225(4):392-408
The idea of morphogen gradients has long been an important one in developmental biology. Studies with amphibians and with Xenopus in particular have made significant contributions to demonstrating the existence, identity, and mechanisms of action of morphogens. Mesoderm induction and patterning by activin, nodals, bone morphogenetic proteins, and fibroblast growth factors have been analyzed thoroughly and reveal recurrent and combinatorial roles for these protein growth factor morphogens and their antagonists. The dynamics of nodal-type signaling and the intersection of VegT and beta-catenin intracellular gradients reveal detailed steps in early long-range patterning. Interpretation of gradients requires sophisticated mechanisms for sharpening thresholds, and the activin-Xbra-Gsc system provides an example of this. The understanding of growth factor signal transduction has elucidated growth factor morphogen action and provided tools for dissecting their direct long-range action and distribution. The physical mechanisms of morphogen gradient establishment are the focus of new interest at both the experimental and theoretical level. General themes and emerging trends in morphogen gradient studies are discussed. 相似文献
77.
Bionomics of Anopheles maculatus complex and their role in malaria transmission in Thailand 总被引:1,自引:0,他引:1
E S Upatham C Prasittisuk S Ratanatham C A Green W Rojanasunan P Setakana N Theerasilp A Tremongkol V Viyanant S Pantuwatana 《The Southeast Asian journal of tropical medicine and public health》1988,19(2):259-269
The bionomics of Anopheles maculatus complex and its role in malaria transmission were conducted in Pakchong and Sadao districts, Nakhon Ratchasima and Songkhla provinces, respectively, from January 1984 to July 1985. In Pakchong, An. maculatus species A was the most dominant species, followed by species B form F and species C which was rare. The densities of species A and species B form F were high between July and November, with their peaks in October. Biting activities of both species occurred through out the night, with a major peak during the first quarter of the night on all seasons. In Sadao, only An. maculatus species B form E was detected with peak densities between February and June. Biting activities of this species varied according to seasons. The prevalence of mosquitoes was influenced by monthly rainfall, relative humidity and air-temperature. All species of female An. maculatus complex studied prefered to feed on animal rather than on human, and tended to bit human more outdoors than indoors, and thus exhibiting a zoophilic and exophagic behaviour. Life expectancies of An. maculatus species A ranged from 1.6 to 6.6 days, species B form F from 1.1 to 8.1 days, and species B form E from 0.7 to 21.2 days. The natural malaria infection rate was very low. Out of 4,430 guts dissected, only 0.23% were found infected with oocysts. There were no sporozoites detected in the 4,472 dissected salivary glands. 相似文献
78.
A six-year-old boy with divergent elbow dislocation is reported, emphasizing the rarity of this condition. A literature review revealed only three roentgenographically documented divergent elbow dislocations in the pediatric age group. Reduction is usually accomplished with ease; however, a full range of elbow motion and forearm rotation must be obtained to ensure complete reduction of the radiohumeral joint. 相似文献
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S Lu D D Parekh O Kuznetsova S A Green C A Tozzi T F Reiss 《The European respiratory journal》2006,28(4):772-780
Cholinergic antagonists have been used since the early 1900s as bronchodilators for chronic obstructive pulmonary disease (COPD). The present study investigated whether an oral muscarinic M3-selective anticholinergic agent (OrM3) would provide an improved therapeutic advantage compared with an inhaled anticholinergic agent in patients with COPD. A 6-week, multicentre, randomised, placebo- and active-controlled, parallel-group study was performed at 56 sites in the USA. In total, 412 male and female patients (aged 35-86 yrs) with a clinical history consistent with COPD were randomised to receive OrM3 0.5, 2, 3 or 4 mg orally once daily, ipratropium bromide 36 mug by inhalation four times daily or placebo. OrM3 demonstrated a significant dose-related improvement in serial forced expiratory volume in one second and a trend for dose-related improvement in patient-reported symptoms compared with placebo. However, at a dose that provided efficacy less than that of ipratropium, the incidence of dose-related, mechanism-based side-effects for OrM3 exceeded those observed for ipratropium. In patients with chronic obstructive pulmonary disease, the oral M3-selective agent did not offer a therapeutic advantage over inhaled ipratropium. These results do not support the hypothesis that high selectivity for muscarinic M3 receptors over airway neuronal M2 receptors will represent a more effective therapy than current inhaled anticholinergics in obstructive airway disease. 相似文献