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11.
Jochen Wolffgramm 《Psychopharmacology》1990,101(2):233-239
To study the effects of different kinds of social deprivation on voluntary ethanol (ETOH) intake male Wistar rats were housed by (a) individual caging, (b) contact caging (partial social deprivation), and (c) group caging (four individuals per cage). In the latter condition the individuals were separated once a week from each other for 24 h. The rats simultaneously received water 5%, 10% and 20% ETOH for a period of 14 weeks. Additional control animals received water. Isolated individuals drank significantly more alcohol than group-housed or contact-caged rats. After a few days they preferred the 20% solution. Circadian measures revealed a discontinuous intake of high doses (> 0.5 g/kg/h) during short time periods. Contact-caged rats consumed much less ETOH, but both the preference for 20% ETOH and the circadian course of intake were similar to those occurring after isolation. ETOH intake of group-housed individuals was low. These individuals preferred the 5% solution and continuously consumed small ETOH doses. During the period of short-term isolation they drank even more ETOH than long-term isolated individuals. In contrast to the latter, the enhancement of intake decreased after some weeks. It is suggested that the differences between the housing groups not only reflect different degrees of isolation stress, but may also be explained by a contribution of different reinforcing or aversive psychotropic effects of ETOH. Reduction of isolation stress is probably most important in the situation of short term separation, whereas dose-dependent reinforcement via social stimulation or sedation may affect the drug taking behavior under the other social conditions. 相似文献
12.
目的 为进一步实验需要,建立子宫内膜间质细胞模型。方法 胶原酶消化联合应用差速离心和密度梯度离心法分离纯化目的细胞;恒温孵箱培养细胞;倒置显微镜观察细胞形态;台盼兰染色计数细胞存活率;免疫组化鉴定细胞。结果 该方法分离纯化子宫内膜间质细胞的存活率高,形态与子宫内膜腺上皮细胞易区别。体外培养的间质细胞具有一定分裂增殖能力,传代培养的形态特征与原代细胞一致。免疫组化显示Vimentin(+)-Kera 相似文献
13.
Dr. Maurizio Vaglini MD Dr. Filiberto Belli MD Mario Santinami MD Flavio Arienti MD Giorgio Parmiani MD Laura Persiani MD Nicola Santoro MD Maria Grazia Inglese MD Fortunato D'Elia MD Natale Cascinelli MD 《Annals of surgical oncology》1995,2(1):61-70
Background: Therapies of advanced melanoma patients with interleukin-2 (IL-2) and cytotoxic lymphocytes have produced interesting results, but a larger diffusion of these treatments is limited by the severe side effects due to IL-2 systemic infusion. A strictly regional administration of IL-2 and cells by an isolation perfusion (IP) in extracorporeal circulation (ECC) for the treatment of regional melanoma metastases could improve tolerability and efficacy of this specific modality of immunotherapy.
Methods: Ten patients were submitted to adoptive immunotherapy with IL-2 and lymphokine-activated killer (LAK) cells by IP in ECC. The schedule of treatment included the first course of a 5-day systemic administration of IL-2 (Proleukin, EuroCetus 9–12 × 106 IU/M2/day continuous infusion); autologous LAK cells were obtained via leukapheresis and after in vitro activation were given (range 8–28 × 109) along with IL-2 (120-2,400 IU/ml of perfusion priming) to the affected limb by IP; IL-2 (9–12×106 IU/m2/day) was also administered by systemic continuous infusion for 5 days starting on the day after IP.
Results: All patients concluded the treatment without any major local or systemic toxicities. Clinical responses included one complete and six partial remissions; three patients had stable disease. All patients are alive. Follow-up after IP ranged from 12 to 35 months (median: 22). The analysis of circulating lymphocytes revealed the rapid disappearance of LAK cells, suggesting their extravasation and/or endothelial adhesion in perfused tissues.
Conclusions: IP with IL-2 and LAK cells is a new approach for the treatment of in-transit metastases due to cutaneous melanoma. The treatment appears to be feasible and reliable. Further biological and immunological studies should permit amelioration of the present modality of treatment. 相似文献
14.
PreliminaryevaluationofpelvicvascularbedisolationchemotherapyinthetreatmentofadvancedcervicalcarcinomaJiangSenandPostgraduate... 相似文献
15.
The most common group of squirrel monkey vocalizations, peeps, are emitted during different social situations including social separation, affiliative interactions, feeding and aggressive confrontations. The present experiments investigated whether peeps and other vocalizations emitted during different social contexts are pharmacologically altered in a similar manner. First, vocalizations were characterized during (1) social separation in juveniles, and (2) resident-intruder aggressive confrontations between dominant monkeys from different social groups. Then, the effects of alcohol (EtOH) and the benzodiazepine chlordiazepoxide (CDP) on vocalizations during social separation and during aggression were examined. Isolated juveniles emitted only one type of call, the isolation peep. Resident monkeys primarily emitted peeps, but also emitted cackles, chucks, noisy calls and pulsed calls. Aggressive peeps were similar in structure and frequency (kHz) to isolation peeps, but were shorter in duration. At the same doses, both CDP (0.3–3 mg/kg) and EtOH (0.1–1.0 g/kg)reduced explosive motor behaviors and isolation peeps in juvenile monkeys during social separation andincreased threat displays and aggression peeps in resident monkeys during confrontations with an intruder monkey from a different social group. Thus, similarly structured vocalizations that were emitted during social separation and aggression were very sensitive to EtOH and CDP, but the social context determined the direction and magnitude of effects. 相似文献
16.
Jan Piet Franke Jaap Wijsbeek Jan E. Greving Rokus A. de Zeeuw 《Archives of toxicology》1978,42(2):115-121
The potentials of XAD-columns for the isolation of quaternary ammonium compounds from aqueous media have been investigated. When adequate amounts of counter ions (perchlorate, chloride, phosphate, nitrate) were added to the aqueous sample, to the column pretreatment fluid and to the aqueous washing fluid, most quaternary compounds investigated were retained on the column and could be recovered by elution with methanol. This approach proved also suitable for urine. Quantitation of quaternaries isolated in this way from urine samples could be performed on silicagel thin layer plates through visualization with iodine, followed by densitometric evaluation. For decamethonium detection limits were 0.1 g/ml. Recoveries at the 1 g/ml level were between 80–90% with variation coefficients of less than 10%.Presented at the European Meeting of The International Association of Forensic Toxicologists, July 4–7, 1978, Utrecht, The Netherlands 相似文献
17.
Rats were reared from weaning (21 days of age) either in isolation or in social groups of five for 30 days and were then tested for spontaneous locomotor activity and 7 days later for 5-hydroxytryptamine (5-HT) agonist-induced behaviour. Isolation-reared animals displayed locomotor hyperactivity when placed in a novel environment. 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) (2 mg/kg IP) and 8-hydroxy-2-(di-n-propyl-amino) tetralin (8-OH-DPAT) (0.32 mg/kg SC) elicited various components of the 5-HT behavioural syndrome in both groups of animals, with forepaw treading and flat body posture being significantly more pronounced in isolation-reared animals. 1-(2,5-Dimethoxy-4-iodophenyl)-2-aminopropane (DOI) (2.5 mg/kg IP), a 5-HT2 selective agonist, produced a significantly greater number of back muscle contractions in isolation-reared animals but there was no difference between the two groups in the number of wet-dog shakes produced. Forepaw treading and flat body posture are thought to be mediated by 5-HT1A receptor activation, and stimulation of this receptor by either 5-MeODMT or 8-OH-DPAT produced greater responding in isolation-reared rats, suggesting supersensitivity of the post-synaptic 5-HT1A receptor. Wet-dog shakes are thought to be mediated by 5-HT2 and other (none-5-HT) receptors while back muscle contractions have been shown to be mediated by 5-HT2 receptors, indicating that there is also an increase in 5-HT2 receptor responsiveness in the socially-isolated animals. In general, the results indicate post-synaptic 5-HT receptor supersensitivity in isolation-reared rats and these receptor changes may be involved in the behavioural profile observed in such rats. 相似文献
18.
2000~2002年我院常见细菌的分离率与耐药监测 总被引:17,自引:2,他引:17
目的 了解 2 0 0 0~ 2 0 0 2年常见菌的分布与耐药状况。方法 采用上海新和公司实验室信息管理系统软件对分离的菌株和药敏试验结果进行分析。结果 大肠埃希氏菌、铜绿假单胞菌、不动杆菌、肺炎克雷伯氏菌、金黄色葡萄球菌分离率占前五位 ,且有逐年增加趋势。大肠埃希氏菌对亚胺培南、头孢西丁、头孢他啶的耐药率在 30 %以下 ,铜绿假单胞菌对哌拉西林、头孢他啶、头孢吡肟、阿米卡星的耐药率在 30 %以下 ,不动杆菌对亚胺培南的耐药率低于 11% ,其余抗生素耐药率均高于 30 % ;金黄色葡萄球菌对复方磺胺甲口恶唑的耐药率在 10 %以下 ,对万古霉素耐药率为零 ,对其余抗生素的耐药率波动较大 ,特别是 2 0 0 2年的耐药率显著上升。结论 动态了解病原菌的分离率 ,熟悉抗生素的敏感性和耐药率有助于临床医生合理应用抗生素 ,制定正确的抗感染方案。 相似文献
19.
20.
医院感染性标本细菌分离的变迁调查 总被引:3,自引:1,他引:3
目的调查本地区感染性标本分离菌株的变迁和流行病学现状。方法采集我院门诊及住院患者感染性标本进行细菌培养,细菌鉴定采用法国生物梅里埃公司VITEK32鉴定系统或手工方法,同时收集临床有关资料进行统计分析。结果2001年1月~2004年12月4年中我院分离细菌居前5位者依次为金黄色葡萄球菌、表皮葡萄球菌、大肠埃希菌、肺炎克雷伯菌及铜绿假单胞菌,真菌检出率占第6位。结论应重视医院耐药菌株的动态监控工作。 相似文献