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61.
The adenosine-producing ectoenzyme 5'-nucleotidase has recently been shown to undergo a marked redistribution during development of the cat visual cortex and to be involved in the remodelling of ocular dominance columns (Schoen et al., J. Comp. Neurol. , 296 , 379 – 392, 1990). Using an enzyme-cytochemical technique, we now investigate the developmental redistribution of 5'-nucleotidase activity in area 17 of kittens at the ultrastructural level. Between postnatal days 35 and 42, when 5'-nucleotidase is concentrated in layer IV, enzyme reaction product occupies the clefts of asymmetrical synapses within the neuropil. During later development (9th and 13th postnatal weeks), when 5'-nucleotidase spreads over all cortical laminae, the enzyme disappears from its synaptic localization and becomes increasingly associated with astrocytic membranes. The transient appearance of 5'-nucleotidase at synapses parallels the time-course and laminar profile of the synaptic remodelling which takes place during the critical period of visual cortex development. This suggests that synapse-bound 5'-nucleotidase activity plays a role in synaptic malleability, whereas its later association with glial profiles is likely to reflect other functions of the enzyme.  相似文献   
62.
Repeated isolation of neonatal rats produces persistent changes in physiology and behavior. In Experiment 1, we examined changes in plasma corticosterone (CORT) levels as a possible mechanism for the effects of isolation. Pups that were isolated from their mother and the nest for 1 h per day on postnatal days (PND) 2–9 were compared to control litters of pups that were either nonhandled or handled but not isolated. On PND 2, compared to nonhandled pups, handled pups had elevated CORT levels that returned to baseline levels within 30 to 60 min of return to the home cage. No significant elevation of CORT levels were found in handled pups on PND 9. The CORT levels of isolated pups were over twice those of nonhandled pups on PND 2 and four times those of nonhandled pups on PND 9. In Experiment 2, we investigated whether the increased CORT release in response to isolation on PND 9 was the result of the pups treatment on the previous six days as against an effect of maturation. Plasma CORT levels were measured in rat pups that were either isolated, handled or nonhandled on PNDs 2–8 during the conditions of isolation, handling and nonhandling on PND 9. There were no differences among the groups in basal plasma levels of CORT. Handling on PND 9 did not result in elevated CORT levels in any of the groups. All three groups showed a significant increase in plasma CORT levels after isolation on PND 9. However, the CORT response to isolation of pups previously isolated on PND 2–8 were significantly higher than pups that were either handled or nonhandled on PNDs 2–8. Thus, daily episodes of isolation potentiate the hypothalamic-pituitary-adrenal response to stress.  相似文献   
63.
钱国英  朱秋华 《营养学报》2003,25(4):446-448
鳖一直被视作为滋补佳品。但以短期快速促生长方式生产的养殖中华鳖的质量与野生中华鳖有区别 [1 ] ,其主要原因是生长时间的差异 ,还是养殖环境等其他因素所造成 ,尚未见报道。本研究通过对相近环境条件下不同年龄的商品鳖和不同环境中同一年龄的商品鳖的营养成分的比较 ,了解养殖周期对商品鳖营养成分的影响 ,为选择合理的养殖周期提供理论依据。1 材 料 与 方 法  由余杭生泰中华鳖养殖有限公司 (YT)提供 2、3龄相同养殖条件仿生养殖中华鳖各 6只 ,2龄中华鳖体重 450~ 50 0 g,3龄中华鳖体重 51 5~ 552 g,均为雄性。养殖池塘面…  相似文献   
64.
目的探讨50岁以上正常人左室舒张期脉冲多普勒频谱的参数变化情况。方法选择一年半时间内受检的所有50岁以上正常人475例,按每10岁为一组分4组进行分析。受检者取左侧卧位,常规显示心尖四腔心切面,取样容积置于二尖瓣尖,使声束与二尖瓣血流方向夹角<15°,以连续三个心动周期的平均值分别测量E峰、A峰、E/A及E峰减速时间并统计。结果发现E峰高于正常值低限的例数、平均E峰血流速度以及E/A均随着年龄的增加而下降,E峰减速时间则随着增龄而增加。结论左室舒张期血流频谱的所有参数与年龄有显著的相关性,明显随着增龄而变化,并且有其规律性。  相似文献   
65.
普通外科危重患者围手术期的营养支持   总被引:6,自引:1,他引:5  
目的:研究普通外科危重患者围手术期营养支持的临床疗效。方法:对1995年以来147例普通外科危重患者围手术期营养支持应用情况进行了分析,腹部手术138例(93.9%),颈部手术9例(6.1%),采用以全胃肠外营养(TPN)为主的阶段性营养支持方法补充营养。深静脉置管方法:经颈内静脉置管132例(89.8%)、腋静脉11例(7.5%)、股静脉4例(2.7%),使用单腔导管127例(86.4%),双腔20例(13.6%),41例(27.9%),放置肠内营养(EN)管。106例(72.1%)为TPN→PN 口服饮食→口服饮食,41例(27.9%)为TPN→PN EN→EN→EN 口服饮食→口服饮食。结果:本组营养支持期间无置管和代谢并发症。142例(96.6%)康复,5例(3.4%)死于原发病。结论:普通外科危重患者围手术期营养支持是重要辅助治疗方法,可保证手术安全,促进术后康复。  相似文献   
66.
腹部手术患者吸入七氟醚与异氟醚麻醉恢复的比较   总被引:2,自引:0,他引:2  
目的比较腹部手术患者吸入七氟醚与异氟醚麻醉恢复的情况。方法全麻下行开腹手术患者40例,随机分为2组(n=20):七氟醚组(S组)及异氟醚组(Ⅰ组)。麻醉诱导后行气管插管,机械通气。诱导后吸入纯氧,氧流量2 L/min,30min后调整为1 L/min。手术开始前,调整吸入麻醉药的呼气末浓度为1.0 MAC。麻醉维持:吸入七氟醚或异氟醚,间断静脉注射罗库溴铵和芬太尼,维持血压和心率波动幅度不超过基础值30%。缝皮结束时,停止吸入七氟醚或异氟醚,纯氧流量调整为5 L/min。记录睁眼时间(停止吸入麻醉药到睁眼的时间)、拔除气管导管时间(停止吸入麻醉药到拔除气管导管的时间)、Aldrete评分达到9分时间(从停止吸入麻醉药计时)及麻醉后恢复室(PACU)停留时间。记录吸入麻醉药用量。结果与Ⅰ组比较,S组睁眼时间、拔除气管导管时间、Aldrete评分达到9分时间及PACU停留时间缩短(P〈0.05),吸入麻醉药的总用量和单位时间用量差异无统计学意义(P〉0.05)。结论与异氟醚比较,吸入七氟醚患者麻醉恢复较快,且麻醉恢复质量较好。  相似文献   
67.
Fourteen adult patients undergoing elective major abdominal surgery were divided into two groups. One group received epidural and general anesthesia (epidural group), and 20 ml of 0.125% bupivacaine and 2 mg of morphine were administered epidurally about 30 min before the end of the operation for post-anesthetic analgesia. The other group (control group) received general anesthesia alone with nitrous oxide, oxygen and enfiurane. Flow-directed pulmonary arterial and radial arterial catheters were inserted preoperatively, and hemodynamic, respiratory, neuroendocrine and metabolic variables were measured serially. The data were compared during anesthesia and the immediate post-anesthetic recovery period. In the control group, the plasma epinephrine level in the post-anesthetic recovery period increased about four times over the anesthetic period. Oxygen consumption was increased and mixed venous oxygen saturation was decreased significantly. There was a close linear correlation between oxygen consumption (Y) and plasma epinephrine (X) level: Y = 285.7X + 90.5 (P < 0.01, r = 0.72). On the other hand, plasma epinephrine, oxygen consumption and mixed venous oxygen saturation did not change significantly in the epidural group in the post-anesthetic recovery period. There was also a close linear correlation between oxygen consumption (Y) and oxygen delivery (X): Y = 0.22X -32.0 (P < 0.01, r = 0.89). We conclude that the surgical stress and anesthetic reversal may seriously influence neuroendocrine responses and subsequently increase plasma epinephrine. Tissue oxygenation and metabolic imbalance may occur due to the rapid increase of epinephrine in the postanesthetic recovery period. Epidural analgesia at this period may play a more important role and have a more favorable effect on the tissue metabolism.  相似文献   
68.
Photic evoked responses were recorded from the striate cortex of Long-Evans hooded intact, monocular visual deprivation (MD) and MD treated with NGF rats. The averaged visual evoked responses (AVER) were obtained from both hemispheres and provided comparison after binocular photic stimuli between the contralateral and the ipsilateral striate cortex with relation to the MD eye. One month of monocular visual deprivation at the critical period of development resulted in marked reduction of the amplitudes of AVER components as compared to the control recordings (P < 0.001). These changes of the AVER could be prevented by NGF infusion to lateral ventricle at the dosage of 2.0–2.4 μg/day for four weeks during the monocular deprivation. In conclusion, the change of AVER amplitudes induced by monocular visual deprivation during the critical period of development can be prevented by NGF infusion to lateral ventricle.  相似文献   
69.
抗肿瘤药复方三生注射液的研究   总被引:1,自引:0,他引:1  
复方三生注射液是由生附片等六味中药组成的静注用灭菌水溶液。本文综合报道了该制剂的制备方法,质量分析,抗肺癌作用的药理及临床等研究的主要内容。结果表明,本品是治疗中晚期肺癌有效的中药复方注射剂。  相似文献   
70.
摘要:目的:观察益气活血补肾壮骨方在骨质疏松症(气滞血瘀型)患者双膦酸盐药物休假期的临床疗效和不良反应等。方法:将本院2019年12月—2021年7月就诊120例气滞血瘀型骨质疏松症双膦酸盐药物休假期患者按照随机数字表均分为两组。对照组予钙片、阿法骨化醇胶囊、金天格治疗,研究组予钙片、阿法骨化醇胶囊加用益气活血补肾壮骨方治疗。治疗6个月后,比较两组患者骨代谢、细胞因子、骨密度、 健康调查简表(SF-36评分)、脆性骨折发生率、骨折风险评估、中医证候积分、疗效和不良反应等。结果:治疗前两组各项指标比较差异无统计学意义(p>0.05)。治疗后研究组骨代谢低于对照组(BGP25.69±4.07vs26.37±4.16ng/mL、PINP35.79±7.38vs37.02±8.12ng/mL、CTX0.85±0.14vs1.26±0.21mmol/L、TRACP8.93±1.26vs13.06±2.59u/L),细胞因子(IL-1:26.36±3.07vs23.75±2.93pg/mL、IL-6:82.71±6.25vs78.62±9.08pg/mL、TNF-α5.03±1.02vs3.81±1.09ng/L)高于对照组,差异有统计学意义(p<0.05)。研究组SF-36评分(87.46±8.32vs70.62±6.59)、西医有效率(86%vs80%)、中医症候积分(23.46±5.32vs21.62±4.59)、中医疗效有效率(84%vs76%)高于对照组,左股骨颈BMD(0.68±0.05vs0.70±0.06g/cm2),脆性骨折发生率(2%vs8%)、骨折风险评估(1.49±0.32vs2.63±0.47)低于对照组,但差异无统计学意义(p>0.05)。结论:益气活血补肾壮骨方联合钙片、阿法骨化醇胶囊可改善双膦酸盐药物假期患者(气滞血瘀型)骨代谢水平,抑制骨吸收和炎性因子水平、促进骨形成、提高骨密度,降低脆性骨折发生率和骨折风险,提高中医症候积分、生活质量,从而提高疗效,疗效水平与金天格相当。  相似文献   
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