川芎茶调冲剂的解热镇痛作用

川芎茶调剂给小鼠灌胃的最大耐受量为44.76g/kg,按最大耐受量的1/12,1/24,1/48设置川芎茶高、中、低3个剂量灌胃给药,川芎茶使大鼠炎症足和非炎症足的痛阈均显著上升,能提高大鼠鼠尾电刺激的痛阈值,对电刺激家免齿髓致痛也有显著抑制作用,结果表明川芎茶调剂具显著的解热镇痛作用.     

特效止痛宁的镇痛作用及机理研究

特效止痛宁经小鼠肌肉注射测得LD_(50)为7.59±1.08ml/kg,按LD_(50)的1/5,1/10,1/20设置药效学试验高、中、低3个剂量组.特效止痛宁肌肉注射,能显著延长热板法小鼠痛反应时间,其镇痛效果可维持2h以上;高、中剂量组对电刺激兔齿髓致痛有显著止痛作用,使光辐射热至大鼠甩尾反应时间延长,对电刺激大鼠鼠尾致痛及钾离子皮下透入致痛等均有显著镇痛效果.其镇痛机理既在外周,也可通过中枢发挥镇痛作用.     

蛇毒注射液药效学及一般药理学研究

蛇毒注射液显著预防和治疗大鼠佐剂性关节炎,及鸡蛋清、甲醛所致的大鼠关节炎,抑制大鼠棉球肉芽肿的生长,降低毛细血管通透性,提高动物的免疫功能,抑制2,4—二硝基氯苯所致的迟发型超敏反应,对大鼠、小鼠、家猫、家兔的神经系统无不良影响,对心血管系统、呼吸系统无明显毒副作用.     

The neuroscience of perceptual categorization in pigeons: A mechanistic hypothesis

We are surrounded by an endless variation of objects. The ability to categorize these objects represents a core cognitive competence of humans and possibly all vertebrates. Research on category learning in nonhuman animals started with the seminal studies of Richard Herrnstein on the category “human” in pigeons. Since then, we have learned that pigeons are able to categorize a large number of stimulus sets, ranging from Cubist paintings to English orthography. Strangely, this prolific field has largely neglected to also study the avian neurobiology of categorization. Here, we present a hypothesis that combines experimental results and theories from categorization research in pigeons with neurobiological insights on visual processing and dopamine-mediated learning in primates. We conclude that in both fields, similar conclusions on the mechanisms of perceptual categorization have been drawn, despite very little cross-reference or communication between these two areas to date. We hypothesize that perceptual categorization is a two-component process in which stimulus features are first rapidly extracted in a feed-forward process, thereby enabling a fast subdivision along multiple category borders. In primates this seems to happen in the inferotemporal cortex, while pigeons may primarily use a cluster of associative visual forebrain areas. The second process rests on dopaminergic error-prediction learning that enables prefrontal areas to connect top down the relevant visual category dimension to the appropriate action dimension.     

The Dynamics of Preschoolers' Categorization Choices

The present research explored the effects of stimulus and task factors on preschoolers' (Experiments 1 and 3) and adults' (Experiment 2) tendency to categorize according to taxonomic relations, when those relations conflict with appearances. In Experiment 1, we examined the effects of and interactions among ( a ) available information, operationalized by using more- or less-informative stimulus types (objects vs. line drawings) and by the presence or absence of labeling, and ( b ) task constraints, operationalized by comparing sorting questions with inductive inferences questions. When provided with information that constrained the categorization decision, either through the availability of labels or a combination of enhanced physical informativeness of objects and an inference question, preschoolers reliably based their categorization decisions on taxonomic relations between physically dissimilar items. In Experiment 2, stimulus type (objects vs. line drawings) was shown to have a similar effect on adults. In Experiment 3, we examined the effects of stimulus type on preschoolers' inductive inferences and accuracy of naming. The effects in the two tasks were closely related, suggesting that the amount of available information affects different responses in similar ways. These data demonstrate the interactive effects of available information and task constraints on categorization decisions.     

The Development of Preschoolers’ Living Kinds Concept: A Longitudinal Study

Given limitations in the integrative scope of past research, basic questions about the organization and development of preschoolers’ living kinds concept remain open to debate. This study was designed to address past limitations through use of a longitudinal design, extensive stimulus set, and alternate indices of understanding. Thirty‐five English‐speaking 3‐year‐olds from middle‐class families in Albuquerque, NM participated in four testing sessions over 1 year. Indices of understanding included statements that preschoolers generated about various living and nonliving objects, biological properties they attributed to the objects, and their characterization of objects as “alive” or not. Results reveal a multifaceted picture of developmental change in preschoolers’ living kinds concept involving both the construction and elaboration of a core biological understanding.     

Effects of compound or element preexposure on compound flavor aversion conditioning

Two experiments with rat subjects examined conditioning of an aversion to a compound flavor stimulus after preexposing the compound, its constituent elements, or no explicit flavor stimulus. Experiment 1 used a short-term procedure in which preexposure and conditioning treatments occurred on the same day; Experiment 2 used a long-term procedure in which more extensive preexposure was administered several days before conditioning. In both experiments, preexposure of the elements slowed conditioning to the compound more than did preexposure of the compound itself. These effects were apparently not mediated by changes in pseudoconditioned or neophobic responses. The results were related to Lubow’s conditioned attention theory of stimulus preexposure effects.     

Approach and escape to conspecific odors of reward and nonreward in rats

A three-compartment box was used, and a reward odor, or nonreward (extinction) odor, produced by another rat, was present in the middle compartment. Two control odor procedures were also used. The results showed that rats will approach a location in which another rat has previously been given reward more rapidly than they will escape from that location, but showed the opposite effect when the odor was produced by a rat undergoing extinction. The mere presence of an odor associated with another rat had the effect of producing much slower locomotion as compared to a no-odor control condition.     

The implementation of clay modeling and rat dissection into the human anatomy and physiology curriculum of a large urban community college

After a considerable amount of research and experimentation, cat dissection was replaced with rat dissection and clay modeling in the human anatomy and physiology laboratory curricula at La Guardia Community College (LAGCC), a large urban community college of the City University of New York (CUNY). This article describes the challenges faculty overcame and the techniques used to solve them. Methods involved were: developing a laboratory manual in conjunction with the publisher, holding training sessions for faculty and staff, the development of instructional outlines for students and lesson plans for faculty, the installation of storage facilities to hold mannequins instead of cat specimens, and designing mannequin clean‐up techniques that could be used by more than one thousand students each semester. The effectiveness of these curricular changes was assessed by examining student muscle practical examination grades and the responses of faculty and students to questionnaires. The results demonstrated that the majority of faculty felt prepared to teach using clay modeling and believed the activity was effective in presenting lesson content. Students undertaking clay modeling had significantly higher muscle practical examination grades than students undertaking cat dissection, and the majority of students believed that clay modeling was an effective technique to learn human skeletal, respiratory, and cardiovascular anatomy, which included the names and locations of blood vessels. Furthermore, the majority of students felt that rat dissection helped them learn nervous, digestive, urinary, and reproductive system anatomy. Faculty experience at LAGCC may serve as a resource to other academic institutions developing new curricula for large, on‐going courses. Anat Sci Educ. 7: 38–46. © 2013 American Association of Anatomists.     

Effects of motor activity on the elicitation and modification of the startle reflex in rats

In order to examine the effects of efferent processes on the elicitation and modification of startle behavior, we administered startle-eliciting stimuli to rats while they were engaged in spontaneous motor activity. When tone bursts (Experiment 1) or electric shocks (Experiment 2) were used to elicit the reflex, its amplitude was substantially less when the rats were active than when they were quiet. Grooming, face washing, and consuming were associated with the greatest reduction. The ability of a 50-dB auditory prepulse to inhibit a subsequent auditory startle was also reduced during activity (Experiment 3). The amount of inhibition produced by a prepulse was decreased even when the baseline startle responses were equated in quiet and activity by varying the intensity of the eliciting stimulus, indicating that the reduction was not due to an artificial “floor effect” (Experiment 4). The study demonstrated that both sensory and motor events affect reflexive responses in the rat, as is known for the human.     

Heading in the rat: Determination by environmental shape

After a 75-sec intratrial delay, rats that had been shown the location of hidden food within a rectangular box correctly dug at that location in a second identical box, which had been moved into the same position within the room. For some rats, the opposing ends of the boxes were differentiated by distinctive corner panels; for others, there were no panels. When, during the delay interval, the turntable supporting both boxes was rotated by more than 180°, so that the second box no longer took the place of the first box within the room, the rats showed performance decrements. Nevertheless, 4 subjects selected the correct location significantly more often than the rotationally equivalent location, which corresponds to the correct location when the ends of the box are confused. The amount of rotation had no significant effect for any rat. In a final phase, the rats were denied perceptual access to cues outside the test box, which now had differentiating corner panels for all rats. Despite the distinctive panels, no rat showed a significant difference between correct digs and rotational errors; that is, no rat reliably distinguished one end of the box from the other. Results confirm previous findings that rats rely primarily on environmental shape to establish their heading. They ignore distinctive features of the surfaces that define environmental shape, even when the shape by itself is insufficient to establish a unique orientation.     

Spontaneous recovery evoked by a nonreinforced stimulus

Pigeons (nine groups of seven) were given one acquisition session of 20 trials. The following day their responding was extinguished, and after a 30-min rest period they were tested for residual response strength. The groups differed with respect to (1) whether a distinctive stimulus was presented during acquisition on the first trial, the 15th trial, or not at all, (2) whether or not responses to the distinctive stimulus were reinforced, and (3) whether a distinctive stimulus, a standard stimulus, or a completely novel stimulus was presented on the test trial. Results supported the position that a stimulus associated with the onset of an acquisition session, but not with the extinction session, evokes greater response strength on a spontaneous recovery test trial than do other stimuli in the acquisition session. This holds true even if responses to this stimulus are never reinforced. In addition, it was found that, unlike a previous study that invoked five daily acquisition sessions, pigeons did not demonstrate increased responding to a novel stimulus.     

Recovery of conditioned fear by a single postextinction shock: Effect of similarity of shock contexts and of time following extinction

Subjects in six experimental groups (n = 16 each) received one-trial passive avoidance (PA) training in which shock was delivered upon movement from a white wooden floor compartment to a black grid compartment. Then fear was extinguished (30 min) in the black compartment. After either 24 or 168 h, all the groups were treated in a room distinctively different from the training room. At each interval, one group received a shock in an apparatus similar to the conditioning box, another received a shock in a dissimilar apparatus, and another was placed in a neutral box. A PA test trial in the training apparatus indicated reinstatement of extinguished fear in all the groups given a postextinction shock except the 24-h dissimilar group. Control groups revealed that the extinction treatment was effective and that spontaneous recovery was not evident. The results were explained in terms of classical conditioning, stimulus generalization, and the broadening (flattening) of stimulus generalization gradients with time.     

Effects of US parameters on classical conditioning of cat hindlimb flexion

Unconditioned stimulus (US) intensity and duration were manipulated to determine their effects on cat hindlimb flexion conditioning. Seven consecutive days of acquisition training of a hindlimb flexor response to a tone conditioned stimulus (CS) were followed by 2 days of extinction. Eight animals in each of 12 groups received a 1-, 2-, 3-, or 4-mA, 60-Hz shock delivered to the right hindleg for 25, 50, or 100 msec as the US. Analysis of conditioned-response (CR) frequency indicated that conditioned responding was a positive function of both the intensity and duration of shock, although these variables did not interact with one another. CR latency and amplitude were decreased and increased, respectively, by increases in US intensity. The pattern of results reported here may support a contiguity notion of conditioning, and are discussed in the context of other conditioning preparations.     

Behavioral field analysis in two strains of rats in a conditioned defensive burying paradigm

Two strains of rats (albino Wistar and hooded PVG/c) were exposed to a conditioned defensive burying paradigm that consisted of placing rats in a test chamber with bedding material on the floor, shocking them with a shock prod, and recording the time each rat spent in burying responses toward the prod. Various behaviors other than burying (freezing, grooming/paw licking) were observed by a time-sampling procedure during the control, conditioning, and extinction sessions, each of which was 15 min in duration. Wistar rats generally showed behavioral inhibition, as evidenced by less burying, lower exploratory and ambulatory behavior, and higher freezing behavior. PVG/c rats spent significantly more time engaged in burying and accumulated more bedding material in the conditioning session than did the Wistar rats. No significant differences between the two strains of rats were observed during the extinction session in terms of these measurements. The results indicate that Wistar rats have a greater tendency to freeze when coping with the noxious stimulus in a conditioned defensive burying paradigm, whereas the dominant coping style for PVG/c rats is defensive burying.     

Protein deprivation and food-related risk-taking preferences of rhesus monkeys

The relative preferences of four rhesus monkeys for reward probability versus reward amount when they were maintained on a low-protein (3.35%) diet were compared with those demonstrated when they were fed an adequate (13.4%) protein diet. Four stimulus objects, each signifying a different combination of reward frequency and amount (100%-one piece, 50%-2 pieces, 33%-three pieces, or 25%-four pieces), were presented in pairs, one pair per daily session, with trial schedules providing the same amount of reward within each set of 12 trials. Selections of the more frequently rewarded objects, but with lesser amounts per trial, were significantly higher during the low-protein phase than during either the preceding or the following normal-diet phases. Protein deprivation produces a changed motivational state making these animals less tolerant of infrequent or postponed reinforcement.     

止痛软胶囊的镇痛研究

止痛软胶囊经NIH小鼠灌胃测得LD_(50)为89.04g生药/kg,按LD_(50)的1/8,1/16,1/24设置药效学高、中、低3个剂量组,止痛软胶囊显著减少腹腔注射醋酸引起的小鼠扭体反应次数,使刺激鼠尾致痛的电压增加,对电刺激免齿髓致痛有显著抑制作用.止痛软胶囊还有明显的镇静作用.     

The role of experimenter-odor cues in the performance of object-memory tasks by rats

Two experiments assessed whether odors left on stimulus objects by experimenters who handle them might confound the interpretation of ostensibly visually guided object-memory tasks for rats. In Experiment 1, rats were able to discriminate the relative recency with which an experimenter touched two otherwise identical objects (intertouch interval = 4 sec), presumably on the basis of an odorintensity discrimination. However, after the rats mastered the odor discrimination with no delay between when the second of the two stimulus objects was last touched by the experimenter and when the rats were permitted to attempt the discrimination, their performance dropped to chance levels when this delay was increased to 15 sec. In Experiment 2, rats were trained in two slightly different ways to perform a delayed-nonmatching-to-sample (DNMS) task, one that involved systematic differences in the temporal order in which the experimenter handled the sample and novel stimulus objects and one that did not. There were no significant differences in the rate at which rats mastered the DNMS task with these two procedures, and the performance of rats that were trained according to the former procedure was unaffected when they were switched to the latter procedure. Moreover, rats required considerably fewer trials to master the DNMS task than the rats in Experiment 1 required to master the odor discrimination. These findings demonstrate that, under certain circumstances, rats can discriminate the relative recency with which two objects are handled by an experimenter, but that this ability contributes little to their performance of conventional object-based DNMS tasks.     

Potentiation of delayed matching with variable delays

In a delayed matching-to-sample procedure, pigeons chose a comparison stimulus that matched a sample stimulus presented earlier in the trial. The duration of the delay between sample-stimulus presentation and comparison-stimulus presentation was either varied over five values within each session or held constant within each session but varied over five blocks of sessions. Accuracy of matching to sample was higher overall with variable delays than with delays fixed within sessions. The result indicates that remembering depends on the temporal context provided by delay intervals.     

The development of word retrieval abilities in the second year and its relation to early vocabulary growth

The present research investigated the development of word retrieval abilities late in the second year when most children display a marked increase in word production. When asked what was hidden in a given box, children with still quite limited productive vocabularies were reliably less likely to produce the labels of the hidden objects than were children with larger productive vocabularies even though (1) all children could name those objects and (2) all children did well when asked to find those same hidden objects. Additionally, the provision of pictorial cues facilitated word retrieval, especially in the early stage of lexical development. Naming errors during a naturalistic book-reading session peaked in children whose productive vocabularies had recently begun to expand, further suggesting that word retrieval processes undergo significant changes at this time.