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1.
本文主要述及:(1)脊髓损伤后局部组织中的强啡肽含量升高,免疫活性增强,κ受体结合力也增强。纳洛酮可明显减轻脊髓外伤造成的后果,促进神经功能的恢复;(2)预先给予κ受体特异性拮抗剂nor-BNI可显著减轻鞘内给予强啡肽A(1—17)所致的损伤;缺乏阿片样活性的强啡肽A(2—17)致脊髓损伤的剂量大于强啡肽A(1—17),且其效应不为nor-BNI所拮抗;(3)预先给予抗强啡肽A的抗血清,显著改善脊髓外伤的程度,促进功能恢复;(4)预先给予强啡肽可加重脊髓外伤,κ-受体拮抗剂可减轻之;(5)NMDA受体和Ca~(2+)在强啡肽致脊髓损伤中可能起着重要作用。以上资料说明强啡肽在脊髓损伤中有重要作用。  相似文献   

2.
【目的】为了明确柳毒蛾Leucoma salicis(Linnaeus)交配的日节律高峰,温度和不同交配持续时间处理对成虫寿命、产卵量和孵化率等繁殖生物学的影响。【方法】将新羽化的柳毒蛾成虫置于养虫笼中,观察交配的日节律高峰,并统计不同温度和不同交配持续时间处理下的成虫寿命、产卵量和孵化率。【结果】成虫在羽化当晚的后半夜凌晨开始交尾,次日晚上开始产卵。成虫交配集中在羽化翌日凌晨3:00—5:00之间,高峰为4:00。产卵高峰都出现在2日龄成虫,但是,25℃下成虫交配持续时间(9.2 h)显著短于28℃(11.8 h)。交配持续时间为30、60和300 min的处理,雌成虫平均寿命显著长于对照(对照9.2 h),雄虫仅60 min的处理显著长于对照。同时,极短的交配持续时间(30 min)显著降低雌虫的产卵量和孵化率。【结论】试验明确了成虫交配的日节律高峰,在适宜的温度范围内(25~28℃),雌雄成虫的寿命、单雌总产卵量无显著差异,交配持续时间明显影响成虫寿命、产卵量和卵孵化率。  相似文献   

3.
目的:研究珂立苏(肺表面活性物质)联合经鼻间歇性正压通气(NIPPV)治疗新生儿呼吸窘迫综合征(NRDS)的临床效果.方法:选取2010年4月-2012年4月我院NICU收治的符合NRDS诊断标准的患儿46例,将患儿随机分为试验组29例和对照组17例.试验组患儿给予珂立苏联合NIPPV治疗,对照组患儿仅给予NIPPV治疗.比较两者患儿治疗前及治疗后6h、24h、48h呼吸功能参数变化情况、X线胸片评分改变情况及3d内存活率.结果:(1)呼吸功能参数情况:试验组患儿上机时(用药前)及用药后6h、24h、48h后肺顺应性(C值)随通气时间进展而逐渐升高,氧合指数(OI值)、呼吸指数(RI值)及肺泡-动脉氧分压差((A-a)DO2值)均随通气时间进展而逐渐下降.试验组患儿经珂立苏治疗后6h、24h、48h和对照组比较,C值均显著高于对照组(P<0.01),OI值均显著低于对照组(P<0.01),RI值均显著低于对照组(P<0.01),(A-a)DO2值均显著低于对照组(A-a)DO2值.(2)X线胸片变化:试验组患儿上机时(用药前)及用药后6h、24h、48h后X线胸片评分逐渐降低,且用药后6h、24h、48h后每一时间点评分均显著低于对照组(P<0.05).(3)患儿3d内存活率:试验组患儿存活率96.4%显著高于对照组70.1%(P<0.05).结论:肺表面活性物质(珂立苏)联合经鼻间歇性正压通气(NIPPV)能明显改善患儿肺通气、换气功能,降低患儿死亡率,治疗新生儿呼吸窘迫综合征临床疗效显著优于单纯应用NIPPV治疗.  相似文献   

4.
目的:观察不同给药时间分别给予比索洛尔对非杓型原发性高血压患者的降压疗效和血压节律恢复的影响。方法:选取60例非杓型高血压患者,采取随机平行对照试验,观察比索洛尔(n=30)每日早晨(8:00)给药2.5-10mg、比索洛尔(n=30)每日夜间(20:00)给药2.5-10mg治疗8周后的降压疗效。结果:两种给药方法均能降低非杓型高血压患者的全天血压(P<0.05)。两种给药方法在白天的血压控制上无显著性差异(P>0.05),但在夜间血压的控制上夜间服药降压效果具有显著性差异(P<0.05)。夜间服药在血压节律恢复方面优于早晨服药(P<0.05),早晨服药组有10例恢复杓型,夜间服药组有19例恢复杓型。结论:比索洛尔的两种给药方式均能安全有效的降压,但对于非杓型高血压患者夜间服药优于早晨服药,更有利于血压节律的恢复。  相似文献   

5.
Wang JL  Wu ZH  Wang NQ 《生理学报》2005,57(1):91-96
实验旨在探讨腺苷A1受体在对基本呼吸节律调制中的可能作用。制作新生大鼠离体延髓脑片标本,主要包含面神经后核内侧区(themedial region of the nucleus retrofacialis,mNRF),并保留完整的舌下神经根。以改良Kreb‘s液灌流脑片,记录mNRF吸气神经元的电活动,并同步记录舌下神经根呼吸节律性放电(respiratory rhythmical discharge activity,RRDA)。在灌流液中先分别单独给予腺苷A1受体的特异性拮抗剂8-环戊-1,3-二丙基黄嘌呤(8-cyclopenty 1-1,3-dipropylxanthine,DPCPX)和特异性激动剂R-苯异丙基-腺苷(R-phenylisopropyl-adenosine,R-PIA);再分别先后给予R-PIA和R-PIA DPCPX,观察RRDA和吸气神经元电活动的变化。结果显示,给予腺苷A1受体拮抗剂DPCPX后,呼气时程和呼吸周期明显缩短,吸气神经元中期放电的频率和峰频率显著增大;给予腺苷Al受体激动剂R-PIA后,吸气时程、积分幅度和吸气神经元中期放电的频率和峰频率均显著降低,呼吸周期明显延长,且R-PIA的呼吸抑制作用可部分地被DPCPX逆转。实验结果提示,腺苷A1受体可能通过介导吸气神经元的抑制性突触输入参与节律性呼吸的调制。  相似文献   

6.
[目的]明确中国传统药食两用资源昆虫九香虫Aspongopus chinensis Dallas繁育特性,为其人工养殖奠定基础。[方法]九香虫实验室内饲养观察其交配产卵的时间节律,分析其交配次数与时长的关系。[结果]研究表明九香虫一天中的交配频次近呈"V"形,两个交配高峰分别为00:00—2:00和20:00—22:00,在10:00—16:00一般不发生交配;在交配总时长未达到15 h以前,交配时长随雌虫的交配次数的增加而增加,交配时长为(8.92±1.97)~(15.36±2.85)h;产卵一般在15:00—20:00进行,大约5~6 min产下一枚卵,卵呈圆柱形,产卵持续1~2h。[结论]九香虫交配产卵具有显著节律性,雌虫的交配次数会显著影响其交配时长。  相似文献   

7.
秸秆焚烧对土壤有机质和氮磷钾含量的影响   总被引:4,自引:0,他引:4  
秸秆露天焚烧作为对废弃秸秆常见的处理方式在中国普遍存在。目前的研究多集中在焚烧对区域大气环境的影响,对土壤环境的化学效应研究较少。因此,为揭示大田秸秆焚烧对土壤生物化学性质的影响,设置不焚烧(CK)、减量焚烧(A1)、全量焚烧(A2)、增量焚烧(A3)4个处理,通过连续4个月的田间小区定位试验,探究不同小麦秸秆焚烧量对耕层0—5 cm土壤有机质含量、微生物数量、土壤养分含量的即时效应和各指标在玉米各生育期内的变化情况。结果表明:小麦秸秆焚烧1 d后土壤有机质含量和微生物数量相对于CK显著降低(P0.05)。其中,有机质含量在焚烧后减少11.0%—22.1%,真菌数量降低30.8%—56.1%,细菌数量降低50.6%—72.6%,放线菌数量降低46.9%—68.3%。土壤全效和速效养分含量显著增加(P0.05):全磷含量增加6.5%—12.9%,全钾含量增加4.6%—18.1%,全氮含量增加2.6%—13.2%。速效磷含量增加9.8%—39.1%,速效钾含量增加13.2%—39.1%,铵态氮含量增加8.6%—38.7%,硝态氮含量增加1.4%—9.2%。各指标的变化幅度随焚烧量的增多而加大(A3A2A1)。玉米生育期内,焚烧处理的土壤有机质含量平均恢复5.6%(A1A2A3)。与有机质相比,焚烧处理土壤微生物数量恢复程度较高,其中细菌的恢复速率最快。在玉米苗期各焚烧处理的真菌、细菌和放线菌平均数量相对于CK依次降低12.7%、17.4%、11.9%,在大喇叭口期和成熟期,微生物数量与CK间差异不显著。速效养分含量在玉米生育期显著高于CK。在玉米苗期、大喇叭口期和成熟期,相对于CK速效磷含量平均增加24.9%、27.0%、29.2%,速效钾平均增加24.0%、14.1%、15.2%,铵态氮平均增加25.5%、23.1%、20.2%,硝态氮平均增加20.8%、19.2%、19.8%。  相似文献   

8.
目的:探讨时钟基因BMAL1在运动性骨骼肌损伤恢复中的作用。方法:208只8周龄SD大鼠随机分为对照组(C组,n=104)和运动组(E组,n=104)。E组于跑台进行90 min下坡跑,运动后于0 h, 6 h, 12 h, 18 h, 24 h, 30 h, 36 h, 42 h, 48 h, 54 h, 60 h, 66 h, 72 h各取C组、E组8只大鼠腓肠肌,通过实时荧光定量PCR实验检测骨骼肌核心时钟基因BMAL1表达量,应用余弦分析软件circacompare (R package)获取拟合余弦曲线参数,分析其节律性振荡的变化趋势;透射电镜观察骨骼肌肌纤维超微结构变化;免疫印迹法(Western blot)检测骨骼肌BMAL1、DESMIN表达;免疫荧光观测BMAL1与DESMIN的定位及含量变化。结果:C组BMAL1 mRNA在72 h内呈现3个完整近日节律周期;E组BMAL1 mRNA在0 h~24 h近日节律消失。与C组比较,E组在运动后0 h、6 h、12 h、18 h, BMAL1 mRNA含量显著升高(P<0.05),在运动后0 h、12 hBMAL1蛋...  相似文献   

9.
实验以淡水(0.3‰)处理组为对照,研究了急性高渗胁迫(盐度16‰和30‰)对中华绒螯蟹(Eriocheirsinensis)雄蟹血淋巴和肝胰腺中可溶性蛋白质、血蓝蛋白、血糖及肝糖原含量的影响。结果显示,与对照组相比,进入16‰及30‰盐度后,蟹的血淋巴中可溶性蛋白质含量从6—48h显著降低(P<0.05),至72h时显著增加(P<0.05),而机体肝胰腺的可溶性蛋白质含量从12h开始至96h显著降低(P<0.05);血蓝蛋白含量在前24h显著降低(P<0.05),48h开始显著升高(P<0.05);肝糖原含量在6—96h与对照组相比有显著的降低(P<0.05);16‰盐度组蟹的血糖含量在24—48h时显著下降(P<0.05),到72h开始逐渐恢复(P>0.05),而30‰盐度组其血糖含量早在6—12h时就有显著的下降(P<0.05),到24h则开始逐渐升高。研究表明,在急性盐度胁迫下,糖类和蛋白质对中华绒螯蟹渗透压调节起重要的作用,其优先利用糖类的分解获得所需的能量,其中盐度越高,机体内葡萄糖的消耗越快,血糖水平的恢复也相应较快。对蛋白质的利用稍次之,机体可利用蛋白质的分解获得其渗透压调节的效应物游离氨基酸以维持渗透压平衡。  相似文献   

10.
目的:探讨CPAP(Continuous Positive Airway Pressure)联合肺表面活性物质治疗新生儿呼吸窘迫综合征(NRDS)临床疗效及对血气指标的影响。方法:选择2014年8月至2018年8月本院收治的新生儿呼吸窘迫综合征患者200例,将其随机分为2组,每组100例。A组给予CPAP(持续正压通气)联合肺表面活性物质治疗,B组给予CPAP(持续正压通气)治疗,分析和比较两组的临床疗效及治疗前后血气指标的变化。结果:治疗后,两组新生儿患者PaO_2均较治疗前均显著升高,PaCO_2较治疗前明显降低,且A组PaO_2显著高于B组(P0.05),PaCO_2显著低于B组(P0.05);A组住院时间显著短于B组(P0.05),临床总有效率显著高于B组(P0.05);两组新生儿患者的胸部X线评分均较治疗前显著降低(P0.05),A组12 h和24 h胸部X线评分均显著性低于B组(P0.05);A组PEEP/cmH_2O水平显著低于B组(P0.05),Fi O_2水平显著高于B组(P0.05);两组生儿患者的的OI指数均较治疗前显著升高,且A组明显高于B组(P0.05)。结论:CPAP联合肺表面活性物质治疗NRDS的临床效果显著优于单用CPAP(持续正压通气)治疗,且且可显著改善患儿血气指标。  相似文献   

11.
李海燕  刘切熠 《生理学报》1990,42(5):420-427
It is known that contemporary space station revolves at the altitude of 400-500 km in the outer space. The present study was undertaken to investigate the effects of simulated space rhythm (L:D = 0.75 h:0.75 h) at this altitude on circadian rhythm in tree shrews (Tupaia belangeri chinensis) and the effects of endogenous sleep inducing neuropeptide Asp5-alpha-DSIP on the space-rhythm-entrained circadian rhythm. This primitive stock serves as one species of Tupaiidae and is a unique native of South China. Our previous studies have shown that this species showed striking differences in natural circadian rhythm between day and night (e.g. 3.03 degrees C of rectal temperature). Results showed that the above mentioned space rhythm (L:D = 0.75h:0.75h) could drastically disturb the inherent circadian rhythm of Tupaia belangeri chinensis. The maximal peak of motor activity dropped significantly in the morning (0600-1200) and a new enhanced peak (more than 20 times greater than that of the control) was found between 1800-2400, whereas the maximal trough of motor activity (2400-0600) remained basically unchanged. Concurrently, the total amount of 24-h motor activity was significantly decreased and the recovery after the cessation of space rhythm was slow. Experimental results also demonstrated that consecutive administration of Asp5-alpha-DSIP (30 micrograms/kg, i.p.) for 5 days (2 days before and 3 days during space rhythm) did not prevent the basic disturbance of circadian rhythm of Tupaia belangeri chinensis caused by the space rhythm (L:D = 0.75h:0.75h). Nevertheless, no decrease or even some enhancement of the total amount of 24th motor activity was observed during space rhythm or after its cessation.  相似文献   

12.
A circadian rhythm in growth was detected by computer-aided image analysis in 3–4-cm-long, juvenile sporophytes of the kelp species Pterygophora California Rupr. and in seven Laminaria spp. In P. californica, the free-running rhythm occurred in continuous white fluorescent light, had a period of 26 h at 10°or 15°C, and persisted for at least 2 weeks in white or blue light. The rhythm became insignificant in continuous green or red light after 3 cycles. Synchronization by white light-dark regimes, e.g. by 16 h light per day, resulted in an entrained period of 24 h and in a shift of the circadian growth minimum into the middle of the light phase. A morning growth peak represented the decreasing portion of the circadian growth curve, and an evening peak the increasing portion. The circadian growth peak was not visible during the dark phase, because growth rate decreased immediately after the onset of darkness. At night, some growth still occurred at 16 or 12 h light per day, whereas growth stopped completely at 8 h light per day, as in continuous darkness. During 11 days of darkness, the thallus area became reduced by 3.5%, but growth rate recovered in subsequent light–dark cycles, and the circadian growth rhythm reappeared in subsequent continuous light.  相似文献   

13.
Circadian periodicity in cell division and death was investigated in the cyanobacterium Anabaena flos-aquae (Lyngb.) Bréb in a phosphorus (P)-limited, N2-fixing chemostat culture. When entrained under 12:12 h LD cycles, not only cell division but also cell death showed a clear circadian rhythm in this filamentous cyanobacterium. The rhythm persisted under continuous light and was temperature compensated. Circadian rhythm was clearly observed in the steady-state cell number and instantaneous growth rate, μ(t), which reached a maximum at about 2 h before sunset and a minimum at about 2 h before sunrise. The number of dead cells and the instantaneous death rate γ(t) also showed a circadian periodicity; the peak of γ(t) occurred approximately 8 h before that of μ(t). Therefore, cell growth and death in A. flos-aquae appear to be under the control of circadian clocks, and thus it seems that their death is programmed cell death.  相似文献   

14.
高原鼠兔松果腺褪黑激素含量昼夜节律的研究   总被引:2,自引:1,他引:1  
李子巍  杜继曾 《兽类学报》1994,14(3):234-238
自然光照条件下,高原鼠兔(Ochotonacurzoniae)松果腺褪黑激素(Melatonin,MLT)含量呈现明显的昼夜节律(P<0.001,夜间组含量均值与白天组含量均值差异显著性比较)。在2月份的实验中,对18只鼠兔(体重122—164克)松果腺的采样时间分别为02.00,09.00,12.00,18.00,22.00和24.00时。白天MLT含量波动为56—64微微克/松果腺,夜间波动为113—170微微克/松果腺。夜间MLT含量高峰值出现在24.00时。在10月份的实验中,对60只鼠兔(体重102—153克)松果腺的采样时间分别为03.00,06.00,09.00,12.00,15.00,18.00,21.00和24.00时。白天MLT含量波动为77—119微微克/松果腺,夜间波动为139—505微微克/松果腺。夜间MLT含量高峰值出现在03.00时。将2月份和10月份高原鼠兔松果腺MLT含量进行差异显著性比较,10月组显著高于2月组(P<0.05)。结果表明,该动物的松果腺本身对光周期具有敏感性,它能够感知环境光周期的变化,成功地完成神经内分泌的转换。  相似文献   

15.
16.
树鼩24小时昼夜节律的探讨   总被引:5,自引:0,他引:5  
自从Carlsson(1922)时期到现在,树鲍(tupaiidae)的分类地位问题一直引起人们很大的兴趣和讨论。历史上树鼩曾不止一次地被错定为松鼠(Grzimek 1975)。虽然人们对树鼩是否属食虫目(Insectivora),原猿亚目(Prosimiae)或另立新目方面尚存在不少争议,但大多数人都同意灵长类在大约第三纪自食虫目演化而来,而树鼩是目前地球上幸存的少数几种灵长类原宗(Ptimitive stock)中的一种(chiarelli 1974;Lende 1970;Grzimak1975;Casseday等1979)。 树鼩可分成2亚科,6属,47种和约100个亚种,它们绝大部分产自亚洲南部。本研  相似文献   

17.
The double product (DP), systolic blood pressure multiplied by heart rate, is a surrogate measure of myocardial oxygen demand and cardiac workload used increasingly today in medicine. The double product is more strongly correlated with left ventricular mass than the daily blood pressure mean. The purpose of this study was to describe the normative circadian pattern of the double product in healthy normotensive young adults. We studied 125 men and 75 women, 23.0 ± 3.3 (mean ± SD) years of age, without medical history of hypertension and 24h ambulatory systolic/diastolic blood pressure mean consistently below 135/85 mm Hg. Subjects underwent ambulatory blood pressure monitoring at 30-minute intervals for 48 consecutive hours once each season of the year, yielding 930 protocol-correct blood pressure and heart rate time series. Subjects maintained their usual routine of diurnal activity and nocturnal sleep and avoided use of over-the-counter and other medication. Circadian rhythmicity in the double product was established by population multiple-component analysis. The double product rose rapidly from the lowest value, attained 3h before awaking from sleep at night, to a markedly elevated level at the commencement of morning activity. The double product was highest in the afternoon, roughly 7h after the commencement of diurnal activity. In both men and women, the shape of the highamplitude circadian rhythm in the double product was best described by a complex model composed of three cosine curves having periods of 24h, 12h, and 6h. The 24h mean in the double product of 8092.51 ±42.76 (mean ±SD) in men was significantly lower than that of 8353.17 ±37.48 in women (P <.001). The circadian double amplitude of the rhythm was statistically significantly greater (P <.001) in men (50% of the 24h mean) than women (44% of the 24h mean). The double product did not differ between seasons in women, but it did in men (P =.017) due to reduced heart rate in summer. The circadian pattern of large amplitude in the double product and its gender differences must be taken into account when using this variable to assess cardiac workload, risk of left ventricular hypertrophy, and efficiency of antihypertensive therapy. (Chronobiology International, 18(3), 475–489, 2001)  相似文献   

18.
In a natural population of alienicolae of Aphis fabae Scop, on field beans in July 1952, the frequency of moulting of the last larval instar into the alate form was usually relatively high between about 04.00 and 08.00 hr. G. M. T. This high rate was followed by a decline to a lower fluctuating rate for the rest of the day. The moulting rate at night was usually very low.
The high rate of moulting in the morning, just as the temperature is rising, may be due to acceleration of nymphal development which leads to a synchronization of moulting, much as teneral development of alatae, if accelerated, produces flight peaks during the day (Johnson, Taylor & Haine 1957): data on the relations of moulting and nymphal development to temperature are, however, insufficient for making a complete analysis along these lines.
Changes in moulting rate during the rest of the day are correlated with temperature and with time, both independently. A rise of 1°C. ambient temperature is associated with an 11.6% rise in moulting rate: a fall of 1°C. with a drop of 10.5% and a lapse of 1 hr. in time by a 5.4% drop in the rate. Sunshine and humidity show no simple correlation with moulting rate.  相似文献   

19.
大袋蛾性信息素分泌的时辰节律和内分泌控制   总被引:3,自引:0,他引:3  
赵博光 《昆虫学报》1988,(3):236-242
本文报道用定量生测方法发现在成虫期短、无多次生殖循环、成虫不取食的鳞翅目昆虫中存在内分泌对性信息素的控制.大袋蛾Clania variegata雌虫的信息素腺体含量表现每日双峰的时辰节律.将雌虫饲养于两种光暗条件下,不同雌虫的峰期被错开,将恰在峰期前的雌虫中抽取的血淋巴注射于处于低含量期的雌虫中能诱导被注射的雌虫显著增加信息素的分泌.除头、摘除咽侧体或切断心侧体与咽侧体之间的神经均有效地消除信息素的分泌,但对摘除咽侧体的雌虫重植咽侧体却未能恢复其信息素的分泌.然而对低含量期的雌虫注射保幼激素类似物738,能诱导其显著增加信息索的分泌,而江射却未能恢复交配后雌虫的信息素分泌能力.根据本文结果讨论了Barth(1965)的假说.  相似文献   

20.
The rate of oxygen evolution of the tropical red alga Kappaphycus alvarezii (Doty) Doty was measured for 6 days in the laboratory using a computer-aided method for long-term recording. In cool white light, Kappaphycus exhibited a robust circadian rhythm of O2 evolution in the irradiance range of 100 to 1000 μmol photons·m 2·s 1. With increasing irradiance, the period of the free-running rhythm, τ, decreased in blue and increased in red light but did not change significantly in green light. The accelerating or slowing action of blue or red light, respectively, points to two photoreceptors used in the light transduction pathway of the circadian oscillator controlling oxygen evolution or the light reactions of photosynthesis in Kappaphycus. No significant changes of τ were observed with increasing irradiance in cool white light, possibly due to the additive opposing responses caused by blue and red light.  相似文献   

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