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71.
The facilitatory effectiveness of spindle afferent feedback is controlled by modulation of segmental reflex excitability such that the level of muscle activation is appropriate for the task. Phase-dependent modes of reflex modulation have been well-characterized. We hypothesized that segmental reflex excitability of the triceps surae was also modulated in a manner associated with the activation history of the spindle afferents and the segmental reflex pathway during isometric contractions, standing and stepping. In the first experiment. pairs of soleus (S) H-reflexes were evoked 80 ms apart with equal strength stimuli at rest and while subjects isometrically contracted their S against loads of 10%. 20%. and 50% of their maximum voluntary efforts. The percent depression of the second H-reflex relative to the first was used as a measure of the effect of reflex activation history. At rest, the second H-reflexes were depressed an average of 73% relative to the first. The degree of depression was progressively reduced as the plantarflexion torque increased. In the second experiment, paired H-reflexes were obtained from the S and medial (MG) and lateral gastrocnemii (LG) muscles while subjects were standing and during the stance phase of step initiation. The degree of depression of the second H-reflex during standing ( > 78%) was similar in magnitude to that produced at rest in Experiment I. At the end of the stance phase of stepping. depression of the second H-reflex of all three muscles was reduced to less than 25%. We conclude that the segmental reflex excitability is modulated as a function of the reflex activation history during these tasks.  相似文献   
72.
经过数年来政府各有关部委的协商努力,医疗卫生各界人士付出了相当的摩擦成本和交易成本,特别是在抗击非典战役的洗礼后,卫生部新领导的新思路发挥指导作用,公立医院的产权制度改革方向终于明确了。卫生部医政司吴明江司长在全国政协举行的一次研讨会上,就医院产权制度改革发表重要谈话,记者在《健康报》  相似文献   
73.
BACKGROUND: This report examines recurrent pediatric groin hernias and the role of diagnostic laparoscopy in the management of these recurrences. METHODS: A chart review of 19 children presenting with recurrent hernias was performed, analyzing the type of primary hernia, nature of recurrence, preexisting medical conditions, surgical complications at primary repair, and time to recurrence. Diagnostic laparoscopy (DL) was used during the remedial repair of the last nine patients. RESULTS: Seventeen indirect hernias were repaired during the primary repair, and 1 femoral hernia was identified. In one child, no inguinal hernia was identified at the initial operation. Overall, 11 recurrences were found to consist of indirect sacs, and 4 were found to have attenuation of the inguinal floor. Four additional recurrences were found to be femoral hernias. In only 1 patient was a wound factor (infection) thought to play a role in the recurrence. Diagnostic laparoscopy in 9 patients found 4 (44%) to have unsuspected intraoperative findings. Four femoral hernias were identified (3 with unsuspected contralateral femoral hernias). Additionally, 1 unsuspected recurrence of an indirect sac was identified. CONCLUSIONS: Laparoscopy accurately identifies the nature of the defect in children with recurrent groin hernias, detecting unsuspected contralateral indirect, direct, or femoral hernias in 44% of those undergoing laparoscopy.  相似文献   
74.
目的分析剖宫产率升高的原因,寻求解决问题的办法,严格掌握剖宫产的手术指征,使诊治更为科学,确保母婴健康。方法对1996年1月1日 ̄2005年10月31日在我院进行剖宫产手术分娩的1570例病例进行回顾性分析,总结分析剖宫产率上升的原因及因素变迁,并提出相应的对策。结果剖宫产率呈逐年上升趋势,尤其近5 ̄6年来,上升明显,究其原因,胎儿窘迫、头盆不称、孕妇精神因素及部分社会因素为主要因素。结论加强围产期宣教,认真做好孕产期监护,医患之间加强沟通,减少医患纠纷,严格掌握剖宫产指征,以最大限度地降低剖宫产率和母婴死亡率。  相似文献   
75.
Objective: To investigate the distribution of TRPA1 (one kind of the TRP-like ion channel family) channel in the hippocampus and cerebral cortex of rat. Methods: RT-PCR was used to amplify the fragment of TRPA1 in the DRG (dorsal root ganglion), hippocampus and cerebral cortex of adult SD rat. In situ hybridization staining was used to show the distribution of TRPA1 mRNA in the hippocampus and cerebral cortex of adult rat brain. Results: Both RT-PCR and in situ hybridization staining showed that TRPA1 mRNA was expressed in hippocampus and cerebral cortex of the adult rat brain. Conclusion: Our results suggest that there is expression of TRPA1 mRNA both in the hippocampus and cerebral cortex of the adult rat brain.  相似文献   
76.
余度 《医疗设备信息》2006,21(5):65-66,69
本文主要介绍常导型MR磁体温度控制部分的组成、原理及常见故障的分析和维修。  相似文献   
77.
目的 建立临床急诊急救中药物中毒发生率最高的 2 3种药物在血液、胃液或呕吐物样品中的毛细管气相色谱分析法。方法 血液、胃液或呕吐物样品经处理后 ,以溴己新为内标 ,采用SP 5 0 2型气相色谱仪、SE 5 4型毛细管色谱柱、氢焰检测器检测巴比妥、对乙酰氨基酚、异戊巴比妥、苯海拉明、苯巴比妥、氯苯那敏 (扑尔敏 )、普萘洛尔 (心得安 )、阿米替林、多赛平 (多虑平 )、安坦、异丙嗪、苯妥英钠、罗拉、安定、氯丙嗪、甲氧氯普胺 (胃复安 )、三氟拉嗪、硝西泮 (硝基安定 )、思诺思、氯氮平、艾司唑仑、氟哌啶醇、阿普唑仑等 2 3种药物。结果 该方法在选定条件下 ,能将样品中 2 3种药物成分分离 ,线性范围为 0 .0 2~ 30 .0 0mg L ,最低检出浓度为 0 .0 2~ 0 .5 0mg L ,平均回收率为 86 .8%~10 2 .8% ,相对标准偏差为 2 .8%~ 6 .2 %。结论 该方法操作简便 ,灵敏度高 ,可快速、准确地为临床提供诊断依据。  相似文献   
78.
BackgroundOur previous study showed that two different regimens of moderate hypofractionated radiotherapy (HFRT) delivered with helical tomotherapy (HT) are well tolerated in older prostate cancer patients. We provide a longterm efficacy and toxicity after > 7 years of follow-up.Patients and methodsThe study recruited 33 patients from February 2009 to July 2011 (76 Gy/34F; Group-1); and 34 from July 2011 to February 2014 (71.6 Gy/28F; 50.4 Gy/25F for the risk of pelvic lymph nodes involvement (LNI) >15%; Group-2). The primary outcomes were biochemical failure (BF), biochemical failure and clinical disease failure (BCDF), progression-free survival (PFS), overall survival (OS), late genitourinary (GU) and gastrointestinal (GI) toxicity.ResultsThe average ages of two groups were 80 and 77 years and the proportions of patients with LNI > 15% were 69.7% and 73.5%, respectively. At the final follow-up in February 2020, 27.3% and 20.6% cases experienced BF, with a median time until BF of 3.3 years. A total of 38.8% patients reached primary endpoints, in which 18 deaths were reported BCDF events (45.5% vs. 32.4%, p = 0.271). There was no significant difference in 7-year PFS (68.6% vs. 74.8%, p = 0.591), BCDF (45.5% vs. 32.4%, p = 0.271) and OS (71.9% vs. 87.5%, p = 0.376) for full set analysis and for subgroup analysis (all p > 0.05). The incidence of grade ≥ 2 late GU (6.2% vs. 6.3%, p = 0.127) and GI toxicities (9.4% vs. 15.6%, p = 0.554) was comparable.ConclusionsIn older patients with localized prostate cancer, two moderate hypofractionated regimens were all well tolerated with similar, mild late toxicities and satisfactory survival, without necessity of prophylactic pelvic node irradiation.Key words: helical tomotherapy, radiation dose hypofractionation, progression-free survival, follow-up studies, prostatic neoplasms, adenocarcinoma  相似文献   
79.
We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2019. The study encompassed 18,455 CDI cases, 13,735 (74.4%) HA and 4,720 (25.6%) CA. During 2015–2019, HA CDI rates decreased by 23.8%, whereas CA decreased by 18.8%. HA CDI was significantly associated with increased 30-day all-cause mortality as compared with CA CDI (p<0.01). Of 2,506 isolates analyzed, the most common ribotypes (RTs) were RT027, RT106, RT014, and RT020. RT027 was more often associated with CDI-attributable death than was non-RT027, regardless of acquisition type. Overall resistance C. difficile rates were similar for all drugs tested except moxifloxacin. Adult HA and CA CDI rates have declined, coinciding with changes in prevalence of RT027 and RT106. Infection prevention and control and continued national surveillance are integral to clarifying CDI epidemiology, investigation, and control.  相似文献   
80.
44 cats were used in this experiment. The spinal cords of 40 animals were injuredat about L_1 level by using Allen's method (400g/cm) and randomly divided into 2 groups: A)electro-acupuncture treatment group (n=20) and B) control group(n=20). 2 weeks after spinalcord injury, 80% of animals in the treatment group were survival and 45% of animals in the con-trol group were survival. There was significant difference between these two groups (p<0. 05).The motor evoked potential was recorded two weeks after spinal cord injury. The latency of theshort latency peak was 15. 61±4. 98 mS and the amplitude was 10. 61 0. 59 mV in the treatmentgroup; and 21. 7±5. 02 mS and 0. 56±0. 32 mV in the control group. Both latency and amplitudewere significant different between the two groups (P<0. 05, P<0. 05). The Anti-NF-H (neuro-filament) was determined at 2 and 4 weeks respectively after spinal cord injury. The more NF-Hpositive labeling fibers were found in the treatment group than in the control group (P<0. 01 ).The  相似文献   
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