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排序方式: 共有1279条查询结果,搜索用时 15 毫秒
1.
Gene M. Heyman 《Psychopharmacology》1993,112(2-3):259-269
A series of experiments evaluated the determinants of preference for mixtures of ethanol plus sucrose relative to sucrose in rats. One dipper served 10% ethanol mixed with 10% sucrose, and the second dipper served 10% sucrose. Lever presses operated each dipper according to a variable-interval 5-s schedule. In three experiments the subjects were given pre-session meals of sucrose (2.5–20 ml) or sucrose (20 ml) plus chow (5 or 10 g). Pre-session meals decreased responding maintained by sucrose but not responding maintained by ethanol mixture. In two experiments body weight was varied from 85% to 125% of the initial free-feeding values. Increases in body weight, like pre-session meals, decreased responding reinforced by sucrose, but typically did not decrease responding reinforced by ethanol mixture. Throughout most of the study, ethanol consumption remained at about 1.25 ml per half hour session (3–4 g/kg per 30 min). For example, pre-session access to ethanol mixture decreased within-session ethanol consumption, but total consumption, counting both sources, remained about 1.25 ml/session. The within-session patterns of responding also differed. Responding reinforced by ethanol mix decreased as a function of ethanol consumption, whereas responding reinforced by sucrose was relatively constant throughout the session. The simplest explanation of the results is that ethanol's pharmacological consequences regulated preference. 相似文献
2.
T M Crombleholme A A deLorimier N S Adzick M T Longaker M R Harrison K L Cox M B Heyman 《Journal of pediatric surgery》1990,25(8):843-845
Mediastinal pseudocyst is an unusual complication of pancreatitis, with only four cases previously reported in children. The extent of the pseudocyst can be defined by computed tomography or magnetic resonance imaging scan and preoperative aspiration of cyst fluid for amylase level can establish the diagnosis. Endoscopic retrograde cholangiopancreatography to define ductal anatomy can help plan the appropriate drainage procedure. Although exceedingly rare, the diagnosis of pseudocyst should be considered for any cystic mass in the abdomen or thorax, even in the absence of elevated amylase or history suggesting pancreatitis. 相似文献
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P. Heyman D. Duh B. Van Der Kuylen C. Cochez M. Van Esbroeck C. Vandenvelde T. Avsic‐Zupanc 《Transboundary and Emerging Diseases》2007,54(5):276-279
This case report describes a dog suffering from a co‐infection with Babesia and Anaplasma parasites. Anaplasma platys was found to be responsible for the anaplasmosis by molecular biology techniques, while microscopical and serological evidence was found for a coexistent babesiosis, although this could not be confirmed by polymerase chain reaction. Moreover, the possible risk of import of exotic pathogens is highlighted. 相似文献
6.
Our earlier studies using the Consortium to Establish a Registry of Alzheimer's Disease neuropsychological battery showed that delayed recall was a highly sensitive indicator of early Alzheimer's disease. None of the learning and memory measures in the battery were found to be useful in staging the severity of this form of dementia. This study explores the nonmemory functions (fluency, naming, and praxis) of the Consortium to Establish a Registry of Alzheimer's Disease battery and asks whether performance on any of these measures adds to the detection of early Alzheimer's disease or is sensitive to the later progression of the illness. We stratified patients with this disease according to severity (mild, moderate, severe), and compared them with age-, education-, and gender-matched control subjects (group N = 49 each). Multivariate procedures and cutting scores were used to determine the efficacy of the various measures in distinguishing between the cases and control subjects. Impairment of delayed recall was again found to be the best discriminator for detecting mild cases of Alzheimer's disease. Confrontation naming was the only nonmemory factor that assisted in this discrimination. For staging the illness, a combination of measures including fluency, praxis, and recognition memory best differentiated cases with mild dementia from those with either moderate or severe stages of disease. Measures of delayed recall quickly "bottomed out" in the patients with Alzheimer's disease and proved of little value in staging the disorder.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
R Ducroc M Heyman B Beaufrere J L Morgat J F Desjeux 《The American journal of physiology》1983,245(1):G54-G58
Uptake and transport of horseradish peroxidase (HRP) have been observed in both Peyer's patches (PP) and jejunal epithelium (JE), and the quantities transported across each tissue were compared. Steady-state was reached much faster in PP than in JE. In Ringer solution, no significant difference was found between the HRP fluxes conveyed through PP and JE. In the presence of 10 mM glucose, slight net secretion was observed in JE but not in PP. In both tissues, the transport mechanism was shown to be sensitive to metabolic inhibitors. By contrast, in PP, ammonia did not significantly enhance intact HRP fluxes. Intracellular transfer and catabolism were estimated by measuring transepithelial fluxes of tritiated HRP. In PP, fluxes from mucosa to serosa and from serosa to mucosa were both greatly reduced (9.18 +/- 3.9 and 10.5 +/- 5.1 pmol X h-1 X cm-2, respectively) compared with JE (106.02 +/- 16 and 31.3 +/- 9.3). These results indicate that intact HRP fluxes are similar in PP and JE, but that tritiated HRP fluxes (intact plus degraded HRP fluxes) are smaller in PP. Together, these results suggest that the specific characteristics of HRP transport across PP are fast uptake and reduced degradation. 相似文献
8.
Jochanan Benbassat Reuben Baumal Samuel N Heyman Mayer Brezis 《Academic medicine》2005,80(12):1121-1126
How medical students are taught physical examination (PE) skills appears to have changed little since the 1950s. Textbooks are organized according to organ systems and describe methods of eliciting and recording history and PE data using a routine format. In many medical schools, the preclinical teaching programs for clinical examination skills similarly emphasize an orderly collection of data. Teaching students to use diagnostic reasoning is postponed until students have learned history-taking and PE skills. The authors propose three modifications to this educational approach. First, rather than performing the clinical examination using a routine format, students should be encouraged to form diagnostic hypotheses early on while listening to the patient's narrative, and conduct the subsequent search for history and PE data in a reflective way in order to confirm or refute these hypotheses. Second, the authors propose that interviewing patients and conducting the PE be taught by one-on-one tutoring until students achieve mastery. Last, they suggest that the PE be guided not only by students' diagnostic hypotheses, but also by patients' expectations. These modifications are consistent with current trends in medical education that encourage a reflective practice and problem-based learning (PBL), and they also introduce medical students to the precepts of clinical reasoning. The authors suggest that challenging students to seek specific physical findings may increase the likelihood of detecting findings when they are present, and may transform patient interviewing and conducting the PE from routine activities into intellectually exciting experiences. 相似文献
9.
Escutenaire S Chalon P Verhagen R Heyman P Thomas I Karelle-Bui L Avsic-Zupanc T Lundkvist A Plyusnin A Pastoret P 《Virus research》2000,67(1):91-107
Dynamics of hantavirus infection and population densities in rodents were investigated from 1996 to 1999 in southern Belgium. Evidence of Puumala infection was restricted to Clethrionomys glareolus. Although the serotype was not determined, antibodies against hantavirus were also found in eight Apodemus sylvaticus. In fall 1996, the seroprevalence in C. glareolus was high (20.1%, 37 of 184) and the infection was widely distributed in the area studied whereas a focal occurrence of positive rodents and lower seroprevalence rates were recorded in spring 1997 (14.3%, six of 42), fall 1997 (6. 6%, 11 of 166), spring 1998 (6.4%, three of 47) and fall 1998 (6.7%, 11 of 165). A pullulation of rodents was observed in spring 1999 and was associated with a markedly higher seroprevalence in C. glareolus (47.7%, 189 of 396). In all seasons, infection rates in adults were higher than in juveniles and subadults. No significant difference of prevalence was recorded between males and females. In two trapping sites, the temporary disappearance of positive animals after a crash in rodent populations suggests that a threshold in density is necessary for the maintenance of the enzootic cycle. 相似文献
10.
Rhoad RC Davidson RS Heyman S Dormans JP Drummond DS 《Journal of pediatric orthopedics》1999,19(2):164-168
Sixty-two consecutive patients with 73 slipped capital femoral epiphyses (SCFEs) underwent pretreatment planar technetium bone scan to identify the presence of ischemia of the femoral head. The relationship of pretreatment ischemia and the development of avascular necrosis (AVN) was evaluated after a minimum follow-up of 12 months. All patients were treated with spica casting or pinning across the physis. No forceful manipulation was performed. None of the 63 stable SCFEs demonstrated ischemia by bone scan, and none developed AVN. Of the 10 unstable SCFEs, six demonstrated ischemia by bone scan, and five of the six developed AVN. None of the four unstable SCFEs without ischemia on bone scan developed AVN. Pretreatment bone scan is a sensitive predictor for development of AVN in unstable SCFEs and may provide a method for evaluating interventional treatments for AVN associated with SCFE. 相似文献