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21.
Cocaine-treated rats acquired a preference for cocaine-associated contextual stimuli (CS) relative to saline-injected control rats. However, when animals were given repeated tests for conditioned place preference intermittent between conditioning trials, they displayed an attenuation in strength of conditioning. This attenuation was not due to pharmacologic tolerance (Experiment 1), but rather reflected a disruption in learning due to exposure to the CS alone (Experiment 2). Like other examples of classical conditioning, the strength of the conditioned response (CR) as assessed by the conditioned place preference model may be influenced by partial reinforcement. 相似文献
22.
改善胰岛素敏感性对血压影响的相关研究 总被引:3,自引:0,他引:3
目的 :观察胰岛素增敏剂二甲双胍改善 2型糖尿病胰岛素敏感性后对血压的影响。方法 :71例 2型糖尿病人口服二甲双胍 (格华止 ) 85 0 mg,qd-bid。治疗前后测定 BMI、血压、FBG、PBG、FINS、PINS,并按 HOMA模型计算胰岛素抵抗指数和胰岛素分泌指数。结果 :( 1)二甲双胍治疗 8周后 ,BMI治疗前后无显著性差异 ;血压治疗后明显下降 ,降压幅度达 ( 13.1± 4.97) /( 4 .2 2± 9.93) mm Hg,血压治疗前后有显著性差异。 ( 2 )治疗后 F BG、 PBG、 FINS均明显下降 ,治疗前后有显著性差异。 ( 3)治疗后 HOMA-IR下降 ,IAI升高 ,治疗前后有显著性差异 ,但 HOMA-IS、 FINS/FBG无显著性差异。结论 :二甲双胍治疗 2型糖尿病 ,在降低血糖、改善 IR的同时 ,伴有血压的明显下降 相似文献
23.
R. A. Bradbury D. Shirkhedkar A. R. Glanville L. V. Campbell 《Internal medicine journal》2009,39(6):384-388
Background: The aim of this study was to determine whether pre-existing diabetes mellitus increases the risk of rejection, infection and/or death in cystic fibrosis patients undergoing bilateral sequential single-lung transplantation.
Methods: A retrospective audit of 25 consecutive patients with cystic fibrosis who underwent bilateral sequential single-lung transplantation between 1 January 2003 and 31 December 2005 at a tertiary referral hospital was carried out.
Results: Although 32% patients had diabetes diagnosed before lung transplantation, 92% had random blood glucose levels ≥11.1 mmol/L requiring insulin during admission. Patients with pre-existing diabetes had increased infection-related (3.9 vs 1.2, P = 0.01) and putative rejection-related (1.4 vs 0.5, P = 0.04) hospital admissions post-transplantation compared with those without diabetes pre-transplant. During the period of observation, four of eight patients with a prior diagnosis of diabetes died compared with none of 17 patients without prior diabetes ( P = 0.0055).
Conclusion: Almost all cystic fibrosis patients develop hyperglycaemia after lung transplantation, but patients with prior diabetes have more complication-related admissions to hospital and a higher mortality rate. 相似文献
Methods: A retrospective audit of 25 consecutive patients with cystic fibrosis who underwent bilateral sequential single-lung transplantation between 1 January 2003 and 31 December 2005 at a tertiary referral hospital was carried out.
Results: Although 32% patients had diabetes diagnosed before lung transplantation, 92% had random blood glucose levels ≥11.1 mmol/L requiring insulin during admission. Patients with pre-existing diabetes had increased infection-related (3.9 vs 1.2, P = 0.01) and putative rejection-related (1.4 vs 0.5, P = 0.04) hospital admissions post-transplantation compared with those without diabetes pre-transplant. During the period of observation, four of eight patients with a prior diagnosis of diabetes died compared with none of 17 patients without prior diabetes ( P = 0.0055).
Conclusion: Almost all cystic fibrosis patients develop hyperglycaemia after lung transplantation, but patients with prior diabetes have more complication-related admissions to hospital and a higher mortality rate. 相似文献
24.
目的:了解和探讨新生儿出生信息的分布态势及规律。方法:对本院2006年1~6月间所有新生儿出生信息进行样本分析。结果:半年间分娩的新生儿共1075例,其中死亡19例,双胞胎15例,以1028例单胎活产新生儿的出生体重、胎龄及产妇年龄作为研究样本进行分析,统计数据与传统意义上的正常胎龄和新生儿体重基本相符,胎龄、体重均值均有所提高。结论:孕产妇的健康状况和新生儿的体质均有所改善,随胎龄的增加,新生儿出生体重亦随之增加,并且,目前新生儿的整体统计体重要大于现有的临床指标,因此,应对现有的临床指标进行适当调整,重新确定低出生体重儿和巨大儿的临床指标。 相似文献
25.
Kitty Grupp 《Journal of addictions nursing》2004,15(2):81-84
The purpose of this project was to prepare nurses to provide brief interventions for clients with alcohol or other drug (AOD) dependency in order to reduce hospitalization, morbidity, and mortality. The project was a collaborative process between a major medical center and a school of nursing. Nurses were surveyed for understanding of alcohol and other drug assessment, and a day long training was provided to teach techniques of brief interventions. The short-term results included increased knowledge of nurses about AOD assessment. Long-term results indicated that 95% of patients referred to the AOD team were confirmed to have AOD problems (Dunn & Ries, 1997). This project documents the need for nurses to have more knowledge about AOD problems and brief intervention techniques. 相似文献
26.
27.
J. P. G. Kaajan 《Pharmacy World & Science》1989,11(4):112-117
The general management of patients with chronic obstructive pulmonary disease and asthma is discussed. Pathophysiological mechanisms of bronchial obstruction and inflammation are briefly described. The importance of preventive measures is emphasized. Medicine prescribed in chronic obstructive pulmonary disease and asthma, their relative place in treatment schedules and route of administration are reviewed. Finally, the importance of maximal bronchodilatation in exacerbations is stressed and the few indications for antibiotic treatment are discussed. 相似文献
28.
肝癌多药耐药产生与低糖环境的关系 总被引:5,自引:1,他引:4
目的探讨局部微环境低糖与肝细胞癌多药耐药性(MDR)产生的关系及影响机制。方法低糖培养HepG2细胞,应用流式细胞术Annexin V/PI法检测低糖培养的细胞在化疗药物5-氟脲嘧啶(5-Fu)作用后的凋亡情况,分别应用荧光定量聚合酶链反应(PCR)技术和Western blot技术检测低糖培养后HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP的mRNA和蛋白水平的表达。结果在低糖环境下生长时间越长的HepG2细胞对5-Fu的抵抗越强,而且随着低糖培养时间的增加,5-Fu诱导的HepG2细胞的凋亡高峰延迟。低糖培养的HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP在mRNA和蛋白水平的表达随低糖培养时间的延长而升高,以LRP的改变最为显著。结论肝癌生长微环境葡萄糖耐量不足也是肝癌产生MDR的原因之一。低糖可通过上调一组多药耐药相关基因的表达而诱导肝癌的多药耐药性。 相似文献
29.
Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy. 相似文献
30.