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81.
Richard A. Meisch 《Pharmacology, biochemistry, and behavior》1995,50(4):571-580
The establishment of orally delivered etonitazene (a potent opioid) as a reinforcer, was studied in eight rhesus monkeys. Initially, when given concurrent access to 2.5 μg/ml etonitazene and the water vehicle, five of the monkeys rejected the drug, whereas the other three monkeys consumed more drug solution than water. The five monkeys that rejected the drug solution underwent an acquisition phase to establish the drug as a reinforcer. A fading procedure was used to transfer control of responding from a 2% (wt/vol) ethanol solution to a 2.5 μg/ml etonitazene solution. Initially, responding was maintained by contingent deliveries of 2% ethanol. Next, across blocks of six or more sessions, increasing amounts of etonitazene were added in steps to the 2% ethanol solution. Subsequently, the 2% ethanol solution was decreased in steps to zero, leaving only the 2.5 μg/ml etonitazene present. When the fading procedure was completed, dose of etonitazene was varied by increasing the volume delivered, first under fixed ratio (FR 4) and then under an FR 8 reinforcement schedule. The same dose manipulations were made with the three monkeys who did not undergo the fading procedure because they preferred etonitazene over water when first tested. Etonitazene was established as a reinforcer for six of the eight monkeys because drug deliveries exceeded vehicle deliveries across a range of drug doses. 相似文献
82.
Recent evidence suggests that the putative dopamine (DA) autoreceptor antagonists, (+)-AJ 76 and (+)-UH 232, share some neurochemical and behavioral effects with both psychostimulants and neuroleptics. The ability of (+)-AJ 76 and (+)-UH 232 to mimic or antagonize the stimulus effects of cocaine was investigated in rats trained to discriminate 5 mg/kg (N=8) or 10 mg/kg (N=8) of cocaine from saline in a two-lever, water-reinforced, drug discrimination task. In the cocaine (10 mg/kg) group, administration of (+)-AJ 76 (2.5–20 mg/kg) engendered only a partial substitution for cocaine (maximum 60% cocaine-lever responses). Given in combination with cocaine (10 mg/kg), (+)-AJ 76 (2.5–40 mg/kg) did not significantly attenuate the cocaine cue. A fixed dose of (+)-AJ 76 (2.5 or 10 mg/kg) plus various doses of cocaine (1.25–5 mg/kg) did not alter the cocaine dose-response curve. (+)-UH 232 (2–16 mg/kg) produced primarily saline-appropriate responding in rats trained to discriminate 5 mg/kg of cocaine and was unable to block the interoceptive cocaine state when given in combination with cocaine (5 mg/kg). (+)-UH 232 (2 or 8 mg/kg) also did not alter the cocaine dose-response curve. These results suggest that (+)-AJ 76 and (+)-UH 232 elicit only weak or no cocaine-like stimulus effects and, unlike neuroleptics, do not attenuate the cocaine cue. 相似文献
83.
微囊化吲哚美辛片剂的研讨 总被引:2,自引:0,他引:2
以明胶-CAP 为囊材,经复凝聚法制备吲哚美辛微囊,再按所筛选的最佳处方制备微囊化片剂。该片与市售片相比,体外 T_(50)延长约5.6倍,家兔体内达峰时间滞后,能明显减轻对大鼠胃的刺激性。 相似文献
84.
老年患者尿路感染菌群分布及其耐药性分析 总被引:3,自引:0,他引:3
目的 :了解老年患者尿路感染致病菌的菌群分布及其对抗生素的耐药情况 ,为临床合理使用抗生素提供依据。方法 :收集湖北省 15所三级甲等医院 2 0 0 2年尿路感染老年患者清洁中段尿细菌培养分离的 5 34株致病菌 ,对其进行耐药性监测。药敏采用K B法 ,用WHONET 5软件进行数据分析。结果 :共收集致病菌 5 34株 ,其中革兰阴性菌 4 0 9株 (76 .6 % ) ,革兰阳性菌 12 5株(2 3.4 % )。革兰阴性菌中大肠埃希菌检出率最高 (2 6 4株 ,4 9.4 % ) ,其次为克雷白杆菌 (44株 ,8.2 % )。 16 .7%的大肠埃希菌和 2 2 .7%的克雷白杆菌产超广谱 β 内酰胺酶。亚胺培南、阿米卡星、头孢他啶对革兰阴性菌的抗菌活性最强 ,而革兰阴性菌对环丙沙星、庆大霉素、哌拉西林的耐药率均在 5 0 %以上。革兰阳性菌以肠球菌最多见 (6 4株 ,12 % ) ,其次为葡萄球菌属 (43株 ,8.1% )。革兰阳性菌对SMZco、红霉素等的耐药率均在 4 0 %以上 ,但对万古霉素均敏感。结论 :老年患者尿路感染以革兰阴性菌为优势菌株 ,且耐药性日益严重 ,对亚胺培南、阿米卡星、头孢他啶最为敏感。革兰阳性菌宜以万古霉素为首选。 相似文献
85.
Introduction Medication errors are a preventable cause of patient injury. In May 2003, as a result of a joint initiative by the Royal College
of Anaesthetists, the Association of Anaesthetists of Great Britain and Ireland, the Intercollegiate Faculty of Accident and
Emergency Medicine and the Intensive Care Society, a new colour code chart for syringe labelling was introduced. The introduction
of the new system has not been uniform in the Irish Republic with no national guidelines or time scale in place.
Methods A questionnaire was administered to doctors working in Anaesthesia in two Dublin teaching hospitals.
Results As much as 23% had administered an incorrect medication and 53% admitted to a near miss as a result of the introduction of
the new label.
Discussion Future action should focus on practical, common sense interventions including techniques such as those that reduce reliance
on memory, standardization, the use of protocols and checklists, and the elimination of look-alike products. 相似文献
86.
Tuberculosis remained a very significant cause of death in Ireland until the mid-20th century and still occupies a prominent position in the folk memory. As I show with reference to recent Irish media coverage, the global resurgence of tuberculosis is therefore viewed with concern in Ireland. Using data collated by the Health Protection Surveillance Centre between 1998 and 2005 however, I show that the recent increase in tuberculosis incidence in Ireland is less than is popularly perceived. This increase is largely associated with economic immigrants attracted to Ireland by the ‘Celtic Tiger’ economic boom, but there is little evidence to suggest that this has had a negative impact on the Irish-born population. Drug resistance is still a small but growing problem. Whilst vigilance is required, it is argued that the recent increase does not at present indicate a likely return to the situation in the mid-20th century. 相似文献
87.
M. H. Baums G. Spahn M. Nozaki H. Steckel W. Schultz H.-M. Klinger 《Knee surgery, sports traumatology, arthroscopy》2007,15(5):687-644
Frozen shoulder is said to be a self-limiting entity but full recovery often takes more than 2 years. For that, most patients
are unwilling to tolerate painful restriction while awaiting resolution. We prospectively investigated 30 patients (16 women,
14 men) for the outcome of arthroscopic capsular release in idiopathic frozen shoulder. Results were determined by the assessment
of subjective and objective parameters to estimate both shoulder function and general health status. Symptoms persisted without
improvement for a minimum of 6 months of conservative treatment. Preoperative average American shoulder and elbow surgeons
score (ASES) was 35, visual analog scale (VAS) to measure pain was 7, and simple shoulder test (SST) was 4. Mean scores of
the physical component of SF-36 were considerably reduced. Mean forward elevation was 85°, average abduction was 70°, mean
internal rotation was 15°, and mean external rotation was 10°. Patients were followed-up at 6 weeks, 3, 6, 12 months and by
a mean of 36 months. Range of motion for all planes improved (P < 0.05). Median VAS reduced to 2, average ASES increased to 91, and SST enhanced to a mean of 10 (P < 0.05). We stated improvement of the physical components in the SF-36 questionnaire in particular bodily pain and the role-physical
score. There were no significant differences between the measurements in the early postoperative phase compared to the mid-term
follow-up (P > 0.05). Our results demonstrate that arthroscopic release of refractory idiopathic frozen shoulder combined with a gentle
manipulation provides reliable expectations for improvement in both clinical and general health status for most patients.
We recommend the use of a limb-specific and a general-health-status questionnaire to conclude the benefit of the surgical
intervention and contribute the optimization of a therapy concept more effectively. 相似文献
88.
目的 探讨膝关节纤维性僵直手术及围手术期、术后综合康复治疗的方法和意义.方法 26例膝关节纤维性僵直患者,采用髌骨外上方小切口,辅助关节镜下行关节内粘连松解,并结合徒手推拿松解.术前进行心理宣教,术后第2天开始经止痛泵维持在CPM机上行慢速全范围关节活动度功能锻炼,并行主被动伸屈膝功能锻炼、髌骨内推训练.结果 术后平均随访19个月(8~32个月),膝关节活动度从术前平均32°增至113°,平均提高81°.无皮肤坏死、创口裂开、肌腱断裂、骨折等并发症发生.结论 关节镜辅助下小切口松解治疗膝关节纤维性僵直的手术操作简单,创伤小,康复快.膝关节僵直围手术期及术后综合康复治疗,对膝关节功能恢复有重要意义. 相似文献
89.
N. Blanchemain S. Haulon B. Martel M. Traisnel M. Morcellet H.F. Hildebrand 《European journal of vascular and endovascular surgery》2005,29(6):628-632
PURPOSE: Cyclodextrins (CDs) are torus shaped cyclic oligosaccharides with a hydrophobic internal cavity and a hydrophilic external surface. We performed and analysed an antibiotic binding on Dacron (polyethyleneterephtalate, PET) vascular grafts, previously coated with CDs based polymers. METHODS: The CDs coating process was based on the pad-dry-cure method patented in our laboratory. The Dacron prostheses were immersed into a solution containing a polycarboxylic acid, a cyclodextrin and a catalyst, and placed into a thermofixation oven before impregnation with an antibiotic solution (Vancomycin). Biocompatibility tests were performed with L132 human epithelial cells. The antibiotic release in an aqueous medium was assessed by batch type experiments using UV spectroscopy. RESULTS: Viability tests confirmed that the CDs polymers coating the Dacron fibers were not toxic towards L132 cell. Cell proliferation was similar on coated and uncoated grafts. A linear release of Vancomycin was observed over 50 days. CONCLUSION: Our results demonstrate the feasibility of coating CDs onto vascular Dacron grafts. Biological tests show no toxicity of the different cyclodextrins coated. A linear release of antibiotics was depicted over 50 days, demonstrating that cyclodextrin grafting was an efficient drug delivery system. 相似文献
90.
N.D. Stafford L.T. Condon M.J.C. Rogers A.W. MacDonald S.L. Atkin 《Clinical otolaryngology》2003,28(4):314-319
The expression of somatostatin receptors 1 and 2 in benign, pre‐malignant and malignant laryngeal lesions The role of chemotherapy in squamous cell carcinoma of the larynx has not been clearly defined. Whilst toxic chemotherapy regimes may confer a marginal improvement in survival, surgery and radiotherapy remain the mainstay of treatment. Somatostatin is a naturally occurring peptide, which exerts antiproliferative and antiangiogenic effects via five membrane‐bound receptor subtypes. The expression of somatostatin receptor subtypes (SSTRs) 1 and 2 was studied in benign, pre‐malignant and malignant laryngeal specimens. Epithelial expression of SSTR1 was detected in 4/6 (67%) Reinke's oedema, 5/6 (83%) pre‐malignant and 8/12 (67%) malignant specimens, with virtually no stromal or vascular expression. High levels of epithelial SSTR2 expression were noted in all Reinke's oedema specimens, compared with low‐to‐moderate levels in only 2/6 (33%) pre‐malignant and 3/12 (25%) malignant specimens (P < 0.01). This ‘loss’ of epithelial SSTR2 expression may provide a growth advantage in pre‐malignant and malignant laryngeal lesions. Vascular expression of SSTR2 was ubiquitous in all groups, with scant stromal expression. Overall, most (>80%) pre‐malignant and malignant laryngeal specimens expressed at least one of the two SSTR subtypes studied. Somatostatin analogues may have a therapeutic role in squamous cell carcinoma of the larynx. 相似文献