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71.
2-chloroprocaine antagonism of epidural morphine analgesia   总被引:2,自引:0,他引:2  
Background: 2-chloroprocaine (2-CP) used for lumbar epidural anesthesia (LEA) reportedly decreases the efficacy of epidural morphine (EM) administered for post-cesarean section (CS) analgesia. The amount of supplemental i.v. morphine self-administered by the patient via the patient-controlled analgesia device (PCA) is used to study the interaction between EM and 2-CP.
Methods: Forty-two patients scheduled for elective CS were randomly divided into 3 equal groups, and received 2-CP, 2-CP+epinephrine (Epi, 5 μg ml-1) or 2% lidocaine (Lido) with Epi for LEA. All patients received 5 mg EM and i.v. PCA morphine for postoperative pain. Cumulative amount of i.v. morphine used in the first 24 hours as well as the amount of the drug used during each 2-h period were noted. Nonparametric analysis of variance and Chi-squared analysis were used for statistical comparisons.
Results: The mean cumulative 24-h i.v. PCA morphine requirement in the 2-CP, 2-CP+Epi and Lido+Epi groups respectively was 20.5±24, 33.1.5±27 and 4.07±6.3 (mean±SD). The Lido+Epi group used significantly less morphine ( P = 0.01) compared to either of the 2-CP groups with no significant difference between the 2-CP groups. The maximum i.v. PCA morphine use occurred in the first 4 hours following surgery in all three groups.
Conclusion: Analgesic efficacy of EM is decreased when 2-CP is used for LEA compared to when Lido+Epi is used.  相似文献   
72.
在13只恒河猴精索内注射长效局麻药后,睾丸发生明显变化;而且给药剂量不同,睾丸曲精小管改变的程度和恢复正常的时间亦不同。睾丸间质细胞无明显变化;睾酮分泌不减少,无毒性反应。对临床男性节育应用及生殖生理研究均具有意义。  相似文献   
73.
Studies have shown that both food deprivation and response cost have important influences on the magnitude of self-administration of a wide variety of psychoactive drugs. In an attempt to extend these findings to the smoked route of drug self-administration, the effects of food allotment and fixed-ratio (FR) value were evaluated in four male rhesus monkeys trained to smoke cocaine base. In the first phase of the experiment, monkeys were trained to self-administer smoked cocaine base under a chained progressive-ratio (PR), fixed-ratio (FR) schedule during daily experimental sessions. Monkeys were required to make 20 lever-press responses and then five inhalations on a smoking spout to obtain the first smoke delivery. The lever ratio then increased to 60, 140, 300, 620, 1260, 2540, and 4940 for each successive smoke delivery. The initial lever ratio value was reset to 20 at the beginning of each daily session. The body weights of three monkeys were determined under free-feeding conditions. Monkeys were then restricted to 100 g food and, when body weights had stabilized, the daily food allotment was increased to 150 g, approximately 210 g, or greater than 400 g (satiation). As the daily food allotment and body weight increased, the mean number of smoke deliveries decreased in two of three monkeys. In the second phase of the experiment, three monkeys were maintained under either food-satiated or food-restricted conditions. Body weights were maintained at approximately 90% of their free-feeding weights under food-restricted conditions. The cost of the drug (lever FR value) was constant within each experimental session, but was increased after 3 consecutive days of stable responding. Fixed-ratio values were increased from 128 to 256, 512, 1024, and 2048. Monkeys were required to complete the lever FR value and then to make five inhalations on the smoking spout to gain access to 1.0 mg/kg per delivery cocaine base. The mean number of smoke deliveries increased at FR 256, 512, and 1024 when monkeys were food-restricted as opposed to food-satiated. Correspondingly, the mean number of responses increased under food-restricted conditions. Responding continued to increase over a wider range of FR values, and the peak number of responses was higher under food-restricted, as opposed to food-satiated conditions. These results, using the smoking route of administration, are consistent with the hypothesis that food deprivation increases the self-administration of reinforcing drugs.  相似文献   
74.
目的 探讨门脉高压症出血病人肝功能变化情况 ,同时评价应用乌司他丁 (Ulinastatin ,UTI)治疗的效果。方法 将 4 6例肝硬化门脉高压症出血病人分为两组 :Ⅰ组 (n =2 2 )为一般治疗组 ,Ⅱ组 (n =2 4 )为UTI治疗组 ,分别检测Ⅰ、Ⅱ组出血后 1,2 ,4 ,7,10 ,14d血ET变化情况 ,并检测1,7,14d的肝功能。另选肝硬化门脉高压症未出血病人 (n =2 0 ) ,检测血浆ET ,作为对照组。结果 出血后 7,14d ,Ⅰ、Ⅱ组总胆红素 (TBIL)均呈先升高后下降 ,但Ⅱ组较Ⅰ组下降快 (分别P <0 0 5 ,P <0 0 1)。ALT、AST亦呈先升高后下降 ,但于出血后 14日Ⅱ组较Ⅰ组下降快 (P <0 0 5 )。Ⅰ、Ⅱ组出血后 1d血ET浓度较对照组显著升高 (P <0 0 1) ,随后逐步下降。Ⅱ组ET下降较Ⅰ组快 ,于出血后 2d(P <0 0 5 )、4d (P <0 0 1)、7d(P <0 0 5 )有显著差异。出血后 1dⅠ、Ⅱ组ET浓度与TBIL呈正相关 (r=0 734,P <0 0 1) ;Ⅰ、Ⅱ组血ET下降指数与TBIL增高指数呈负相关 (r =- 0 4 86 ,P <0 0 5 )。结论 肝硬化门脉高压症大出血后应用UTI治疗可抑制TBIL、ALT、AST、ET等的升高 ,起到保护肝脏功能的作用。  相似文献   
75.
美宝湿润烧伤膏在治疗慢性泪囊炎的应用   总被引:16,自引:8,他引:8  
目的:观察美宝湿润烧伤膏(MEBO)在治疗慢性泪囊炎的应用价值。方法:对87例102只慢性泪囊炎采用泪道探通手术与MEBO置留治疗。常规泪点表面麻醉,扩张泪点,用生理盐水或氯霉素眼水冲洗鼻泪管、泪囊、泪小管,再用无菌注射器装入5ml MEBO,用5号自制泪道冲洗针沿泪道方向插入,直达泪囊推药,使鼻泪管、泪囊、泪小管内充满MEBO,一周后继续上述方法治疗,一般连续治疗2—5次。结果:治疗总有效率为100%,随访6个月,无一例复发。结论:在泪道探通手术后随即留置MEBO治疗慢性泪囊炎,临床效果良好,操作简单方便,经济有效,值得临床推广应用。  相似文献   
76.
脑胶质瘤患者长期存活的临床因素分析   总被引:4,自引:0,他引:4  
目的 探讨胶质瘤患者长期生存相关的临床因素。方法 回顾性调查1980年5月-1995年5月间在本院手术治疗的胶质瘤患者,对收集的资料整理量化,建立Logistic回归模型(stepwise法)进行分析。结果 长期生存的胶质瘤患者102例,长期存活率占随访病例的43.9%(102/232)。病理级别、年龄、KPS、肿瘤部位、复发、复发后再手术、切除程度和手后放疗与胶质瘤患者的长期存活显著相关,其中复发后再手术、切除程度和手术后放疗是提高患者长期存活率的最重要因素。结论 应尽量在显微镜下行胶质瘤全切除,术后及时放疗和化疗;肿瘤复发时如KPS大于70,特别是第一次手术病理级别低者,应予再手术治疗。  相似文献   
77.
AIM: To investigate how the location of the placenta at term pregnancies affects the duration of the third stage of labor and to discuss the possible mechanisms affecting the duration of the third stage. We believe that this is the first prospective study comparing the duration of the third stage of labor according to placental location. METHODS: The placental implantation was determined as anterior (n = 78), posterior (n = 59), or fundal (n = 64) by ultrasound, in 201 women with singleton pregnancies. After delivery of the newborn, oxytocin infusion was routinely given. Duration of the third stage of labor was compared by anova. P < 0.05 was determined as significant. RESULTS: The duration of the third stage of labor was 10.36 +/- 5.94 min, 10.44 +/- 5.35 min, and 8.12 +/- 4.25 min with placentas located anteriorly, posteriorly, and fundal, respectively. The length of the third stage was significantly shorter in the fundal placenta group. CONCLUSION: In this study, the length of the third stage of labor was approximately 2 min shorter with placentas located at the fundus compared to the other two groups. The mechanism responsible for shorter duration may be the bipolar separation of fundal placentas in contrast to usual unipolar down-up separation of anterior or posterior placentas. Another contributing factor may be the use of oxytocin infusion for the management of the third stage, however this should be investigated by further studies by using real time ultrasonography.  相似文献   
78.
Summary Short term memory to tones (STMT) was investigated by recording single unit activity in the auditory cortex of a behaving monkey. The activity of each unit was studied in two behavioral conditions: a) During task performance, the monkey had to compare two tones separated by one second of silence (inter-stimulus interval), b) During a nonperforming period; the monkey heard the two tones but did not respond behaviorally. It was noted that the firing rate of many units during the inter-stimulus interval (ISI) was dependent on the frequency of the first tone. Such dependency was observed even towards the end of the ISI, both during task performance trials (50% of the units) and during the nonperforming period (32% of the units). The activity of these units could be the basis of STMT in both of these behavioral states. In 65% of all the units tested, the responses during the ISI were of a higher magnitude in the performance period than were the responses in the non-performance period. The activity of these units may be related either to general processes such as attention and expectation or to short-term memory processes. During task performance, the responses of 23% of the units to the second tone were dependent on whether its frequency was identical to that of the first tone. Such dependency was never observed during the non-performing period. These units may detect similarity or non similarity between two tones presented one second apart. Periodic patterns of firing were not found in the study, thus suggesting that the ISI responses were not generated by reverberatory activity in simple closed loops. On the basis of these results, several alternative mechanisms of STMT are suggested.  相似文献   
79.
醒脑静注射液治疗肺性脑病31例疗效分析   总被引:5,自引:0,他引:5  
目的 :探讨醒脑静注射液治疗肺性脑病的临床疗效。方法 :采用随机分组对照法 ,将 6 1例肺性脑病患者分为加用醒脑静组 (治疗组 ) 31例和单纯西药治疗组 (对照组 ) 30例 ,进行疗效对比分析。结果 :治疗组治愈12例 ,有效 15例 ,总有效率 87.10 % ;对照组治愈 5例 ,有效 16例 ,总有效率 70 .0 % ,2组疗效差异有显著性(P<0 .0 5 )。从时效关系看 :治疗组对意识障碍的起效时间〔(72 .0 0± 33.94 )小时〕明显快于对照组〔(117.71± 34.70 )小时 ,P<0 .0 1〕,表现为促醒时间短 ,意识恢复正常快 ,并能达到镇静安神的作用 ;从改善原发病症状、体征及血气指标看 :治疗组在改善头痛、失眠、多语、幻觉、谵妄、狂躁及喘憋等症状方面明显优于对照组 (P<0 .0 5 ) ,对降低 Pa CO2 效果亦明显优于对照组 (P<0 .0 1)。结论 :醒脑静注射液具有开窍醒脑、行痰通瘀、镇静止痉和清热解毒等功效 ,是防治肺性脑病的安全、有效药物。  相似文献   
80.
The question of whether functional residual capacity (FRC) falls in infants during active sleep has been clouded by studies using different subject groups and techniques for measurements of lung volume and determination of sleep state. Twenty healthy full-term infants within the first week of life participated in the present study. Neurophysiological and behavioral criteria were used to define sleep state, and measurements of FRC were made using a specially constructed closed-circuit helium dilution system. Regularity of respiration was recorded using magnetometers on the chest and a modified respirator monitor. Results showed that no significant changes in FRC occurred, related either to sleep state or to regularity of respiration. In addition, we failed to detect any differences in FRC between the sexes. Pediatr Pilmonol. 1989; 7:71–77 .  相似文献   
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