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101.

Introduction

Infant crying is a major expression of distress and can occur without any exogenous stimulation. Little is known, however, about the effects of crying on physiological homeostasis in very preterm infants (VPIs).

Methods

Environmental, behavioral (video and audio recording) and physiologic (heart rate [HR], respiratory rate [RR], and systemic [SaO2] and regional cerebral oxygenation [rSO2]) parameters were prospectively evaluated over 10 h in 18 VPIs (median gestational age, 28 [27–31] weeks). Only episodes of “spontaneous” and isolated cries were analyzed. Changes in parameters were compared over 5-second periods between baselines and 40 s following the onset of crying. Two periods were distinguished: 0–20 s (a) and 20–40 s (b). Minimal and/or maximal values in these periods were also compared to the baseline.

Results

Of the 18 VPIs initially studied, 13 (72%) presented crying episodes (CE). They experienced 210 “spontaneous” and isolated CE, with a median of 9 [range, 1–63] CEs per child. Physiological values varied significantly from the baseline with mainly a mean decrease in HR of − 4.8 ± 5.3 beats/min (b) after an initial mean increase of + 2.6 ± 2.0 beats/min (a); a mean decrease in RR of − 3.8 ± 4.8 cycles/min (a), followed by a mean increase of + 5.6 ± 7.3 cycles/min (b) and mean unidirectional decreases in SaO2 and rSO2 (minimal values) of − 1.8 ± 2.3% and − 2.5 ± 3.0%, respectively.

Conclusion

Spontaneous cries can alter the homeostasis of VPIs. Their possible adverse consequences and high occurrence emphasize the need for better prevention and response to them.  相似文献   
102.
Objective To observe the effect of intrathecal administration of SP600125 on both MWT and TWL of rats after chronic constriction injury (CCI) of the sciatic nerve. Methods 40 male SD rats were randomized to deride into 5 groups (n=8). Rats in group SP5 received SP600125 5 μg after CCI; rats in group SP25 received SP600125 25 μg after CCI; rats in group SP50 received SP600125 50 μg after CCI; rats in group DMSO received 2% DMSO 10 μl after CCI; rats in group Naive received SP600125 50 μg without sciatic nerve injury. SP600125 was dissolved in 10 μl 2%DMSO solvent. On the 7th day after CCI, MWT and TWL were determined with yon Frey filaments and thermal radiation apparatus repectively after intrathecal administration of SP600125. Results Intrathecal administration certain dosage of SP600125 could attenuate the established mechanical allodynia and thermal hyperalgesia induced by CCI rather than normal rats. Conclusion Intrathecal administration certain dosage of SP600125 could attenuate the established mechanical allodynia and thermal hyperalgesia induced by CCI.  相似文献   
103.
Objective To observe the effect of intrathecal administration of SP600125 on both MWT and TWL of rats after chronic constriction injury (CCI) of the sciatic nerve. Methods 40 male SD rats were randomized to deride into 5 groups (n=8). Rats in group SP5 received SP600125 5 μg after CCI; rats in group SP25 received SP600125 25 μg after CCI; rats in group SP50 received SP600125 50 μg after CCI; rats in group DMSO received 2% DMSO 10 μl after CCI; rats in group Naive received SP600125 50 μg without sciatic nerve injury. SP600125 was dissolved in 10 μl 2%DMSO solvent. On the 7th day after CCI, MWT and TWL were determined with yon Frey filaments and thermal radiation apparatus repectively after intrathecal administration of SP600125. Results Intrathecal administration certain dosage of SP600125 could attenuate the established mechanical allodynia and thermal hyperalgesia induced by CCI rather than normal rats. Conclusion Intrathecal administration certain dosage of SP600125 could attenuate the established mechanical allodynia and thermal hyperalgesia induced by CCI.  相似文献   
104.
A human-SP1 immunoassay was used to detect SP1-like material (SP1) in the plasma of cynomolgus monkeys. In 27 females remaining non-pregnant during a mating period of 4 months, SP1 was occasionally detected at a mean concentration of 2.5 ng/ml. In 14 non-pregnant females of subsequent proven fertility, SP1 was detected 20 days following unfertile mating at a mean concentration of 4.8 ng/ml in 86% of cycles. At day 20 of proven pregnancies, SP1 was at 12 ng/ml in 93% of these animals. SP1 levels during pregnancy increased in two steps, a slow rise between days 20 and 50, followed by an abrupt rise between days 50 and 60 and afterwards a plateau at 600 ng/ml. Seven other pregnant monkeys received 10 mg/kg of the antiprogestin RU 486 at 28 days. Four aborted and the others continued their gestation. SP1 was always dramatically depressed by this treatment; in animals with abortion failure, it remained at a low concentration for 3 months, then the normal concentration range was recovered. The assay of SP1-like material does not allow early diagnosis of pregnancy, however, it remains interesting as a follow-up parameter after 60 days. Also, antiprogestins appear to be useful tools to analyse the metabolism of SP1.  相似文献   
105.
目的:用无水乙醇和高强度聚焦超声(HIFU)阻滞后肢动脉闭塞犬腰交感神经节,比较两种处理方式对后肢皮肤温度、神经节形态结构及脊髓P物质影响的差异。方法:27只杂种犬制作后肢缺血模型,术后2周随机分为3组(各组n=9):对照组(A组),HIFU治疗组(B组),乙醇治疗组(C组)。A组不予处理,B组和C组分别用HIFU和无水乙醇阻滞腰交感神经节。各组在造模前、治疗前(造模后2周)、治疗后1周分别检测肢体皮肤温度、神经节形态结构及脊髓P物质含量的变化。结果:(1)三组造模后与造模前相比皮肤温度均显著降低(P〈0.05),治疗后B、C两组回升。(2)镜下B组所有神经元细胞出现坏死;C组大部分神经元坏死。(3)SP免疫阳性反应物集中分布在脊髓背角Ⅰ、Ⅱ层,造模后各组脊髓腰段SP的平均光密度(OD)值与造模前相比均显著升高(P〈0.01),治疗后B、C两组脊髓腰段SP的OD值较治疗前显著降低(P〈0.05),组间无显著差异(P〉0.05),结论:高强度聚焦超声和无水乙醇均可有效阻滞腰交感神经节,两种方法在对后肢动脉闭塞犬后肢皮肤温度、脊髓P物质改变方面影响无显著差异,而HIFU对神经节破坏更彻底。  相似文献   
106.
107.
bcr-abl基因疫苗对小鼠SP2/0/bcr-abl移植瘤的影响   总被引:6,自引:1,他引:6  
为了研究bcr—abl融合基因疫苗对小鼠SP2/0/bcr—abl移植瘤的影响,采用pVbcr—abl、pVbcr—abl/mIL7两种质粒分别免疫BALB/c小鼠,然后用SP2/0/bcr—abl细胞攻击免疫小鼠,观察疫苗对SP2/0/bcr—abl移植瘤生长的影响,检验其是否具有免疫保护作用。结果表明:用基因疫苗免疫的两个实验组与两个对照组(空白对照组和空载体对照组)相比,在移植肿瘤形成时间、肿瘤表面破溃时间、肿瘤体积、荷瘤生存期等指标上均存在明显差异。pVbcr—abl/mIL7免疫小鼠组的荷瘤生存时间比pVbcr—abl免疫组相对延长。常规病理学分析发现,对照组小鼠的移植瘤组织比较致密,瘤细胞体积较大,形状不规则,而两个免疫组的肿瘤组织较为疏松,肿瘤细胞体积相对较小,并有大量炎性细胞浸润。两个对照组小鼠的肝脏组织内发现有大量肿瘤转移灶,而两个免疫组小鼠则未发现。结论:接受bcr—abl基因疫苗免疫的小鼠被诱导产生较强的特异性免疫保护力,对SP2/0/bcr—abl移植瘤的体内生长有一定抑制能力。  相似文献   
108.
BackgroundHypometria is a clinical motor sign in Parkinson's disease. Its origin likely emerges from basal ganglia dysfunction, leading to an impaired control of inhibitory intracortical motor circuits. Some neurorehabilitation approaches include movement imitation training; besides the effects of motor practice, there might be a benefit due to observation and imitation of un-altered movement patterns. In this sense, virtual reality facilitates the process by customizing motor-patterns to be observed and imitated.ObjectiveTo evaluate the effect of a motor-imitation therapy focused on hypometria in Parkinson's disease using virtual reality.MethodsWe carried out a randomized controlled pilot-study. Sixteen patients were randomly assigned in experimental and control groups. Groups underwent 4-weeks of training based on finger-tapping with the dominant hand, in which imitation was the differential factor (only the experimental group imitated). We evaluated self-paced movement features and cortico-spinal excitability (recruitment curves and silent periods in both hemispheres) before, immediately after, and two weeks after the training period.ResultsMovement amplitude increased significantly after the therapy in the experimental group for the trained and un-trained hands. Motor thresholds and silent periods evaluated with transcranial magnetic stimulation were differently modified by training in the two groups; although the changes in the input–output recruitment were similar.ConclusionsThis pilot study suggests that movement imitation therapy enhances the effect of motor practice in patients with Parkinson's disease; imitation-training might be helpful for reducing hypometria in these patients. These results must be clarified in future larger trials.  相似文献   
109.
110.
邹琳  廖靖  吴科锋  张颖  李英勇 《海南医学》2010,21(14):38-41
目的探讨不同压力、不同持续时间的CO2气腹对妊娠中期大鼠近、远期血浆、胎盘组织以及羊水中SP1的影响。方法建立妊娠中期CO2气腹的大鼠模型,取不同压力、不同气腹时间各处理组以及对照组一半大鼠的血液、羊水及胎盘组织行固相夹心法酶联免疫吸附实验(ELISA),检测SP1含量变化。余下一半大鼠养至妊娠晚期,同法处理。结果妊娠中期大鼠CO2气腹后近期血浆中SP1变化差异无统计学意义(P〉0.05),远期血浆中SP1变化差异有统计学意义(P〈0.05)。在相同的气腹压力下,血浆SP1随气腹持续时间延长而降低(P〈0.05);在相同的作用时间下,血浆SP1随气腹压力增大而降低(P〈0.05)。在胎盘组织及羊水中SP1变化差异无统计学意义(P〉0.05)。结论妊娠中期大鼠高气腹压力、长时间CO2气腹后能造成远期血浆SP1的减少,而近期血浆以及近、远期胎盘、羊水中SP1量未见明显降低,血浆SP1的改变先于胎盘组织、羊水出现,可预测胎盘功能不良。  相似文献   
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