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1.
Thalidomide was administered to 44 female rhesus monkeys immediately after they had mated. There were no live births from these animals, whereas there were 11 live births in 57 untreated monkeys. The results are statistically significant. The hypothesis is advanced that thalidomide killed the embryo prior to implantation.  相似文献   

2.
Rats trained to press a bar for intracranial reinforcement gave as many responses during extinction as did water-reinforced controls, when extinction came immediately after an acquisition session. However, the experimental animals gave fewer responses in extinction than water-reinforced animals when extinction was delayed for 1 hour after acquisition. The activity level of the experimental animals was high immediately after acquisition but declined markedly over the delay period, which suggests that resistance to extinction after intracranial reinforcement is primarily a function of activity level.  相似文献   

3.
Puromycin and retention in the goldfish   总被引:1,自引:0,他引:1  
A first experiment compared the behavior of goldfish injected with puromycin immediately after each of a weekly series of brief discriminative training sessions in the shuttlebox to that of appropriate controls. Discrimination was not prevented, nor was escape from shock impaired, but probability of response to the conditioned stimuli, both positive and negative, was reduced substantially. These results suggest that puromycin interferes with the consolidation of conditioned fear. The null outcome of a second experiment, in which all training was given in a single long session instead of a series of short sessions, suggests (contrary to recent indications) that consolidation begins in the training session. The conditioned-fear hypothesis is supported by the results of a third experiment in which the animals were shocked upon entering a goalbox to which they had previously learned to swim for food; animals injected with puromycin, immediately after the shock, entered the goalbox more readily 1 week later than did appropriate controls.  相似文献   

4.
Despite a reduction in liver and body weights of neonatal rats born and reared at a simulated altitude of 5790 meters (oxygen pressure, 76.36 millimeters of mercury), the hepatic enzyme tryptophan oxygenase develops prematurely in these stressed animals as compared to controls reared at sea level. Also, the specific activities remain distinctly elevated through the first 9 days of age; thus, the competence for premature synthesis ot tryptophan oxygenase is confirmed in neonatal rats.  相似文献   

5.
Four monkeys with bilateral hippocampal lesions were trained to respond sequentially to visual stimuli, presented with an automated discrimination apparatus. Two different sequential tasks were presented. The experimental animals were significantly inferior on both problems to six control animals. Since no impairment appeared on simple visual discriminations presented with intertrial intervals from 5 seconds to 6 minutes, simple sensory deficits and "short-term" memory impairments appear unlikely. The results strengthen the interpretation that bilateral hippocampal lesions interfere with the acquisition of those behaviors which involve the execution of sequential responses.  相似文献   

6.
Three groups of monkeys were raised with different degrees of contact with their peers. The first group was allowed no contact, the second only visual and auditory contact, and the third was allowed complete and normal contact with their peers. Animals of all three groups were allowed to interact socially; they were then tested for their preference for monkeys raised under the same conditions or for monkeys raised under different conditions. Monkeys raised under the same conditions preferred each other, even if the stimulus animals were completely strange to the test monkey.  相似文献   

7.
Retarding effect of lowered heart rate on coronary atherosclerosis   总被引:18,自引:0,他引:18  
The role of heart rate in the development of coronary atherosclerosis was assessed in adult male cynomolgus monkeys (Macaca fascicularis). Heart rate was lowered in six animals by surgical ablation of the sinoatrial node. A sham procedure, which included all of the surgical steps except for sinoatrial node ablation, was carried out in eight animals. All of the monkeys were fed an atherogenic high cholesterol diet for 6 months, and heart rates were monitored repeatedly by telemetry during 24-hour test periods. Coronary atherosclerosis in animals with postoperative heart rates less than the preoperative mean for all of the animals that underwent surgery was less than half that of animals with heart rates above the mean or of diet-fed control animals not subjected to surgery. Groups did not differ in blood pressure, serum lipids, or body weight. These results suggest that heart rate in itself may contribute to the mechanisms by which behavioral patterns and physical training influence coronary artery disease.  相似文献   

8.
Newborn monkeys reared in darkness for 16 months, except for daily 1-hour periods of exposure to unpatterned light, were allowed to press a lever to obtain unpatterned light. The animals showed apparently insatiable responding, at rates that were extremely high as compared with rates for normally reared control animals.  相似文献   

9.
KAY K  RIEKE WO 《Science (New York, N.Y.)》1963,139(3554):487-490
The type and fate of mononuclear cells of guinea pigs hypersensitive to tuberculin were studied by means of purified protein derivative labeled with I(125) and mononuclear cells labeled with tritiated thymidine. Purified protein derivative labeled with I(125) was taken up in vitro by lymphocytes and neutrophils from animals that were either sensitive or nonsensitive to tuberculin, but it was bound more frequently by the cells of sensitive animals. Passive transfer of tuberculin hypersensitivity by means of lymphocytes labeled with tritiated thymidine indicated that significant numbers of radioactive cells migrated to the site where the skin was tested with purified protein derivative only when the test was made immediately after transfusion. Although skin reactions from tests made with purified protein derivative 24 hours after transfusion were comparable to those from tests made immediately, the number of labeled cells at the sites of the later tests was not consistently larger than it was in controls (Histoplasmin reactions). Thus transfused tuberculin-sensitive cells are neither always attracted to the sites of the test with purified protein derivative nor are they required in large numbers at the site for a positive reaction to develop.  相似文献   

10.
Three rhesus monkeys Macaca mulatta, formerly dependent on morphine, had increased sensitivity to nalorphine's effect of suppressing operant responding for food, as compared with two monkeys with no history of morphine exposure. Within the dose range employed, nalorphine injections produced emesis, salivation, and hyperirritability in formerly morphine-dependent monkeys but not in controls.  相似文献   

11.
Sixty mice received either shock or no shock in a shuttle box, or nonspecific stress in another apparatus. Brain and liver homogenates from these animals were then injected into 120 naive recipients, who were all tested in the shuttle box. Subjects receiving brain or liver from shocked or stressed donors had significantly higher latencies than control counterparts. These results are interpreted in terms of stress, rather than a memory transfer hypothesis.  相似文献   

12.
Experimental leprosy in three species of monkeys   总被引:4,自引:0,他引:4  
Eleven mangabey monkeys inoculated with Mycobacterium leprae developed lepromatous-type leprosy. Nine of the mangabeys were inoculated with M. leprae isolated from a mangabey with naturally acquired lepromatous leprosy. Immune function was depressed in some of these animals after dissemination of the disease. Two mangabeys developed lepromatous leprosy after inoculation with human M. leprae passaged in an armadillo. Three rhesus and three African green monkeys inoculated with mangabey-derived M. leprae also developed lepromatous leprosy. Mangabeys may be the first reported nonhuman primate model for the study of leprosy. Rhesus and African green monkeys may also prove to be reproducibly susceptible to the disease.  相似文献   

13.
Hemoglobin of 30 Macaca mulatta monkeys and of 15 Macaca irus monkeys consisted of one electrophoretic component similar to human hemoglobin A. Twenty-one M. irus monkeys had two types of hemoglobin. In 20 animals the hemoglobin resembled human hemoglobin AJ, and in one animal it resembled human hemoglobin AI.  相似文献   

14.
Cerebrospinal fluid production by the choroid plexus and brain   总被引:7,自引:0,他引:7  
The production of cerebrospinal fluid and the transport of (24)Na from the blood to the cerebrospinal fluid were studied simultaneously in normal and choroid plexectomized rhesus monkeys. Choroid plexectomy reduced the production of cerebrospinal fluid by an average of 33 to 40 percent and the rate of appearance of (24)Na in the cerebrospinal fluid and its final concentration were proportionately reduced. In both normal and plexectomized animals, (24)Na levels were found to be markedly greater in the gray matter surrounding the ventricles and in the gray matter bordering the subarachnoid space. That sodium exchanges in these two general areas of the brain may be linked to the formation of the cerebrospinal fluid is discussed here.  相似文献   

15.
为了探讨贝伐珠单抗类似药SMMU-13重复静脉注射对食蟹猴的安全性,采用毒理学评价方法,将30只食蟹猴按体重随机分为溶媒对照组、阳性对照组,低、中、高剂量组,每组6只,雌雄各半。低、中、高剂量组给药量分别为2、10和50mg/kg;阳性对照组给予50mg/kg贝伐珠单抗注射液;溶媒对照组给予SMMU-13安慰剂。给药体积均为2mL/kg。每周给药2次,共4个给药周期,恢复期4周。期间进行各项毒理学指标检测。试验结果发现:与自身给药前d0相比,给药期间中、高剂量组及阳性对照组的乳酸脱氢酶(LDH)和甘油三脂(TG)升高;高剂量组及阳性对照组雄性动物股骨骨骺板软骨细胞增生,钙化成骨不良,给药部位近端血管及周围损伤。其余各项指标毒理学指标未见明显异常变化。以上结果表明,SMMU-13主要毒性靶部位为股骨骨骺及给药局部。在本实验条件下安全剂量为2mg/kg,毒性剂量为10mg/kg,与等剂量阳性对照药物毒性反应基本类似。本研究为贝伐珠单抗类似药SMMU-13的临床用药提供了安全用药依据。  相似文献   

16.
Animals injected with venom of the scorpion Centruroides sculpturatus Ewing or venom of the rattlesnake Crotalus atrox Baird and Girard were subjected to high-and low-temperature stress. Unconditioned animals transferred to a modified temperature were less refractory to the venoms than those conditioned for 48 hours, but all animals stressed were less refractory than unstressed animals. Animals receiving a series of small doses of epinephrine were similarly affected. This apparent change in toxicity of the venoms seems to be due to the physiological effects of stress rather than to the temperature per se.  相似文献   

17.
Lentiviral delivery of glial cell line-derived neurotrophic factor (lenti-GDNF) was tested for its trophic effects upon degenerating nigrostriatal neurons in nonhuman primate models of Parkinson's disease (PD). We injected lenti-GDNF into the striatum and substantia nigra of nonlesioned aged rhesus monkeys or young adult rhesus monkeys treated 1 week prior with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Extensive GDNF expression with anterograde and retrograde transport was seen in all animals. In aged monkeys, lenti-GDNF augmented dopaminergic function. In MPTP-treated monkeys, lenti-GDNF reversed functional deficits and completely prevented nigrostriatal degeneration. Additionally, lenti-GDNF injections to intact rhesus monkeys revealed long-term gene expression (8 months). In MPTP-treated monkeys, lenti-GDNF treatment reversed motor deficits in a hand-reach task. These data indicate that GDNF delivery using a lentiviral vector system can prevent nigrostriatal degeneration and induce regeneration in primate models of PD and might be a viable therapeutic strategy for PD patients.  相似文献   

18.
Troops of the black and white colobus Colobus guereza in the Bueclongio Forest, Uganda, average eight animals with a typical composition of one adult male, four adult females, two subadults, one juvenile, and one infant. Solitary males and small all-male groups also occur. Troops of mixed sexes have well-defined territories which coincide roughly with the home range. Territories of five groups averaged 0.062 square mile (0.137 kmn(2)) in area agreeing closely with territory-sizes of Asian Colobine monkeys. Adult males have a roar that is concerned with maintaining territorial spacing, but not with actual territorial defense. The territories of these arboreal, forest animals are much smaller than the home ranges of more terrestrial and nonterritorial open-country primaes.  相似文献   

19.
Three rhesus monkeys which had been isolated from social contact during their first year of life persistently overate and overdrank during adulthood. These monkeys ingested approximately twice as much fluid and food as the control animals reared normally.  相似文献   

20.
Simian acquired immunodeficiency syndrome (SAIDS), a disease clinically and pathologically similar to acquired immunodeficiency syndrome in humans, was transmitted from diseased rhesus monkeys (Macaca mulatta) to normal monkeys by inoculation with heparinized whole blood or plasma that had been passed through filters of 0.45 micrometer pore size. This suggests that the causative agent is small and most probably a virus. No viruses, however, were isolated by standard cell culture techniques from the blood or filtered plasma which caused SAIDS. Both cellular and humoral immunity were markedly depressed in animals with advanced SAIDS.  相似文献   

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