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91.
The aim of this study was to determine the influence of socio-demographic and professional factors on physicians' attitudes to the terminally ill. Between May 1992 and May 1993, a survey was conducted in the province of Pordenone (north-east, Italy) in order to analyse a number of specific issues, such as emotional involvement, the need for aggressive treatments and the communication of diagnosis and prognosis. After obtaining a list of board-certified physicians from the Medical Association office in Pordenone, a modification of the cancer questionnaire of Haley and Blanchard (QSPT) was mailed to 916 doctors. Of these, 605 (60%; 487 male, 118 female; mean age 41 ± 11 SD) returned the completed questionnaire. Within the group of responders, we identified three main subgroups, according to their type of activity: general practitioners (175, 29%), hospital doctors (235, 39%) and other doctors (195, 32%). In age, sex and activity, the only significant difference between responders and non-responders was age (mean age 41 and 43 years respeetively). Most of the responders (77%) stated that they were able to deal with the terminally ill patient and his/her needs; 44%, however, admitted that patients' anxiety is sometimes unbearable. For the vast majority of the doctors polled (91%), providing a comfortable environment for an incurable patient was more important than pursuing aggressive treatment, but only 44% were convinced of the uselessness of aggressive care. To the question on whether to disclose information about imminent death to allow patients to prepare spiritually, 37% answered No, 38% Yes, and 25% were uncertain. Almost all responders (95%), however, believed in the beneficial effect of hope on the terminally ill. Ourresults suggest that doctors' professional and, most of all, sociodemographic and cultural factors determine the relationship with the patient on both the emotional and the clinical decision-making levels.  相似文献   
92.
The spatial distribution of pulmonary blood flow and its change over time was investigated in term fetal rabbits, using the plasma tracer fluorescein-isothiocyanate-labeled bovine serum albumin (FITC-BSA). A tracer bolus was injected intravenously and allowed to circulate in vivo for increasing periods of time (2-30 minutes) prior to arrest of the circulation and tissue preparation. Initially, fluorescence was present in the vasculature of 43% of lung parenchymal tissue, disposed as discrete regions or "lobules." Interspersed regions of lung tissue received no tracer inflow. With increasing tracer circulation times (10, 20, and 30 minutes), a greater percentage of lung cross-sectional area contained vessels exhibiting tracer fluorescence (64, 96, and 100%, respectively). In the fetal lung, a high pulmonary vascular resistance (PVR) is maintained. Our studies indicate that, at any given moment, fetal pulmonary blood flow is distributed only to a proportion of discrete lung "lobules," while interspersed "lobules" receive no flow at all. The "lobules" alternate between these "high" and "low" vascular resistance states with a periodicity of approximately 35 minutes, comprising 22 minutes of non-perfusion followed by 13 minutes of perfusion. This circulatory pattern permits both the maintenance of high PVR and uniform lung development. Further, by directing flow to only a portion of the vasculature, greater microvascular flow rates are achieved and hence the risk of blood sludging and stasis is reduced. Recruitment of these "non-perfused" regions at birth could thus produce a significant reduction in PVR.  相似文献   
93.
Rats were trained in a T-shaped maze to discriminate the effects produced by i.p. injections of tetrahydrocannabinol (THC) and the no-drug state (state-dependency, StD). Several doses of both 8-THC (range: 0.75–5.0 mg/kg) and 9-THC (range: 0.75–10.0 mg/kg) were used in order to compare the number of sessions required by the animals until reaching criterion performance. An additional group of rats had to discriminate pentobarbital sodium (20.0 mg/kg) from the no-drug state.Results: THC discrimination was proportional to dose i.e., animals that had to differentiate high doses of THC from no drug acquired the T-maize task faster than animals trained with the lower doses of THC. Acquisition data further suggest that 8-THC is somewhat less potent than the 9-isomer. 9-THC (10.0 mg/kg) produces strong StD, as defined by Overton (1971), since both this group and the barbiturate group reached the criterion within the first 10 training sessions. Time and dose testings suggest that stimulus properties of drugs vary in a quantitative way and that the calculated ED50 values are mainly determined by the training dose used. It was found that the higher the training dose used the higher was the corresponding ED50 value. Hashish smoke can maintain drug responding among THC-trained rats. A lowered content of brain catecholamines and/or serotonin, induced by AMPT (150 mg/kg) and PCPA (310–350 mg/kg), did not lessen 9-THC (2.5 mg/kg) discrimination.Portions of the results were presented at the Fourth Scandinavian Meeting on Physiology and Behavior, Oslo May 22–24, 1975.  相似文献   
94.
益骨胶囊对成骨细胞增殖影响的时效及量效关系研究   总被引:8,自引:1,他引:8  
目的 :运用中药血清药理学方法 ,观察益骨胶囊含药血清对新生大鼠颅骨成骨细胞 (OB)体外增殖的影响 ,并探讨用于OB药效观察的益骨胶囊含药血清制备条件。方法 :雌性 12月龄SD大鼠 80只 ,随机分为生理盐水组、益骨胶囊低剂量 (11 6g/kg)、中剂量 (34 8g/kg)、高剂量 (10 4 4g/kg)组 ,每日灌胃一次 ,连续 12天 ,分别在灌胃后的 0 5h、1h、1 5h、2h采血 ,分离血清 ,用含不同浓度益骨胶囊的血清培养SD新生大鼠颅骨OB ,MTT法检测细胞增殖情况。结果 :末次灌胃后 1 5h采血组的吸收度 (A)值明显高于各组其它时间 (P <0 0 5 ) ;不同剂量各浓度的益骨胶囊含药血清对体外培养的OB增殖均有显著的促进作用 ,其中以高剂量组的稀释比为 2 5 %的血清浓度最佳。结论 :益骨胶囊含药血清对OB增殖具有明显的促进作用 ;益骨胶囊用于OB药效观察的大鼠含药血清制备条件以人等效剂量 9倍连续 12天灌胃、末次灌胃后 1 5h采血 ,血清添加浓度以 2 5 %为宜。  相似文献   
95.
针药结合治疗失眠症的临床研究   总被引:5,自引:0,他引:5  
目的 :观察针药结合与单纯中药治疗失眠症的临床疗效。方法 :90例患者均以国际通用SPIEGEL睡眠量表检测 ,设针药结合组 (治疗组 )与中药组 (对照组 )各 4 5例。结果 :治疗组疗效优于对照组 (P <0 0 5 )。结论 :针药并用 ,内外兼治 ,疗效显著 ,且远期疗效好。  相似文献   
96.
抗抑郁药物的发展始于20世纪50年代的异烟肼,属单胺氧化酶抑制剂(MAOI),但因易于引起肝脏损害等严重毒副反应而被逐渐淘汰。随后又发展了三环及四环类抗抑郁药物。作用于血清素受体的一系列新药物的发现,揭开了抗抑郁药物研究的新篇章,其代表药物氟西汀(fluoxetine)已成为全球10种最为畅销的药物之一,具有安全性较高、副作用较小的特点。本文从结构与活性关系的角度分析近年来5大类抗抑郁药物的构效关系。  相似文献   
97.
王晓晶 《黑龙江医药》2003,16(2):106-107
目的:探讨按中国药典(2000年版)抗生素微生物检定法测定硫酸卡那霉素含量的最后稀释液浓度范围;方法:应用ZY-300IV型抗生素抑菌圈面积测量分析仪,测定硫酸卡那霉素抑菌圈面积与对数剂量的线性关系范围;结果:测定硫酸卡那霉素含量时,最后稀释液浓度范围在5.5-20.4IU/ml内对数剂量与抑菌圈面积呈直线关系。  相似文献   
98.
天然抗肿瘤药喜树碱衍生物的研究进展   总被引:4,自引:3,他引:4  
潘显道  王存英 《药学学报》2003,38(9):715-720
  相似文献   
99.
噁唑烷酮类抗菌药物构效关系新进展   总被引:5,自引:0,他引:5  
综述新型抗菌药物噁唑烷酮类化合物近几年来的构效关系研究新进展,重点讨论母环上3位和5位的结构改造,噁唑烷酮3位氮原子接-苯环,苯环的对位为杂环取代,5位为乙酰胺甲基、硫代乙酰胺甲基、异噁唑氧甲基等,这些改造所得的化合物大都有良好的抗G^ 菌活性。  相似文献   
100.
In the 11‐residue long dark‐color‐inducing neurohormone (DCIN = [His7]‐corazonin), of locusts, from residue 2 to residue 11, one amino acid at each time was substituted by d ‐phenylalanine (d ‐Phe). The dark‐color‐inducing effect of these peptides was investigated in comparison with unaltered DCIN by a bioassay based on nymphs of a DCIN‐deficient albino mutant of the migratory locust, Locusta migratoria. Substitution of any single amino acid by d ‐Phe always reduced the activity, but did not abolish it completely. Maximum inactivation was obtained after substitution of Gln4, Ser6, or Trp9. The latter two residues are within the partial sequence ‐Ser‐Xxx‐Gly‐Trp‐ (Xxx = His in the DCIN) that seems to be important for the dark‐color‐inducing activity, as found also in another study (Insect Biochem. Mol. Biol. 32, 2002, 909). Gln4, however, is outside of this partial sequence. Minimal, although still considerable, inactivation occurred after substitution of Gly8, Phe3, or Asn11, despite the fact that Gly8 is within the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence. In conclusion, no single active core was found, indicating that the whole sequence of the DCIN is necessary to induce maximum darkening effect. No difference was found in the activity of the peptides in which Gly8 was substituted by d ‐Phe or by L ‐Phe. Therefore the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence does not seem to be stabilized by a type II β‐turn. Nevertheless, existence of another kind of turn that includes this partial sequence is feasible. A single unsuccessful attempt was made to discover an antagonist to the DCIN.  相似文献   
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