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111.
50只大鼠用乌拉坦麻醉,箭毒制动。通过阻断腹主动脉血流以模拟腰段脊髓的局部缺血和再灌流损伤,玻璃微电极记录L2节段脊髓单位放电(SCUDs),观察缺血再灌流时脊髓神经元对腓神经刺激(PNV),内脏大神经刺激(VLNV)及两者同时刺激(SV)的反应。结果在缺血前所记录的133个自发放电单位中,对3种刺激均产生兴奋(E)、抑制(I)及无反应(NR)3种形式的反应,表明大鼠L2节段脊髓存在躯体、内脏和躯体内脏反应性神经元,并有会聚和阻塞现象。在脊髓缺血再灌流时,神经元对PNV、VLNV、SV也产生E、I、NR3种形式的反应,提示脊髓缺血再灌流时神经元对躯体和内脏传入刺激的反应形式不受影响;但缺血时SCUDs对PNV、VLNV产生反应的单位数减少,这表明脊髓缺血损伤时神经元对躯体和内脏传入刺激的反应性减弱,随着缺血损伤加重,脊髓神经元对躯体内脏信号的整合功能下降  相似文献   
112.
刺激视上核对大鼠痛阈及电针镇痛的影响   总被引:2,自引:1,他引:1  
以钾离子透引起的大鼠甩尾反应为痛指标,观察了电和化学刺激视上核(SON)对大鼠痛阈(PT)和电针(EA)镇痛的影响。电刺激SON后,PT明显高于假刺激组(P<0.05~0.001),电刺激SON后电针足三里,镇痛效应明显提高,并有明显的量效关系。电刺激SON的近旁部位(0.5—1mm)对PT及电针镇痛无明显影响。SON内注射L-谷氨酸(L-Glu)后痛阈和电针镇痛效应都明显对照组,也有明显的量效关  相似文献   
113.
测量30例新生儿盲肠和阑尾的形态和位置。回盲口的形状多数(80.00±7.30%)呈不规则形。阑尾根部体表投影在脐水平线下方1.51±8.95mm和腹股沟韧带中点垂线外侧1.26±10.90mm处。  相似文献   
114.
Summary In the last decades back pain has reached dramatic proportions in industrialized countries. Disorders of the back are nowadays the leading cause of direct and indirect health care costs. Accurate prevalence estimates are needed to serve as a basis for health care evaluations. A review of epidemiologic studies in the general population reveals that back pain has reached a prevalence of 40 % for current pain. 7 to 18 % are “frequently”, “often”, “daily” or “constantly” affected. 75 % of the adult population suffers from back pain during the last year. 80 to 90 % of the adult population in industrialized countries experience back pain ever. Gender specific differences are only present in severe, chronic forms which are more often experienced by women. Back pain has a prevalence maximum at 50 to 64 years. Older persons display lower prevalence estimates. The prevalence maximum in men is one decade earlier than in women. There are several potential explanations for this prevalence pattern that are discussed in the article. Back pain can be classified by location, temporal characteristics, pain intensity and pain history. Currently, for none of these dimensions generally accepted, uniformly employed and validated definitions are available. In most of the industrialized countries back pain is one of the most expensive symptoms. 75–90 % of the direct and indirect health care costs were caused by those 5–10 % of patients who are disabled. As predictors of back pain a history of back pain and job satisfaction play by far a more important role than the extensively studied mechanical factors. For a first episode of back pain the prognosis is favorable. If the pain persist for more than three months the prognosis is unfavorable. After six months of absenteeism because of back pain more than half of the afflicted never return to work. Rarely back pain is present as a single symptom. In more than 80 % back pain is associated with pain in at least one joint. It remains to be studied if back pain may be viewed as an entity or as part of a more complex pain syndrome.   相似文献   
115.
116.
无张力疝修补术后顽固性疼痛原因和对策   总被引:1,自引:0,他引:1  
目的 探讨无张力疝修补术后的顽固性疼痛病因及预防治疗。方法 将同期无张力疝修补术与传统的腹股沟疝修补方法进行比较。结果 无张力疝修补术后的顽固性疼痛率为9.02%(12/133),传统的腹股沟疝修补方法疼痛率为8.61%(18/209)。无张力疝修补与传统的腹股沟疝修补相比,术后顽固性疼痛的发生率差异无显著性(P>0.05)。结论 无张力疝修补并不一定减少传统的腹股沟疝修补术后顽固性疼痛,手术规范操作是预防的关键,治疗应先保守治疗,无效再考虑手术治疗。  相似文献   
117.
118.
Congenital analgesia is a rare genetic disorder. We report here that a 12-year-old boy was able to recover from congenital insensitivity to pain. Neurological examinations revealed that there was a 'stocking' distribution of pain decrement on the lower extremities under the patient's knee joints. Magnetic Resonance Imaging (MRI) of his brain showed gyrus thinning with sulcus widening at both sides of the parietal lobe. Southern blot hybridization probed with cDNAs of various opioid receptors did not detect any significant abnormality. Our results suggest that this rare case may not be genetically determined.  相似文献   
119.
Survey of postoperative analgesia following ambulatory surgery   总被引:4,自引:0,他引:4  
Background: The quality of pain relief during the first 48 hours following ambulatory surgery has been poorly documented. This questionnaire study was performed to evaluate the nature and severity of pain after the patient leaves the hospital. Methods: 1100 patients in the age group 5–88 years who underwent ambulatory surgery during a period of 6months were asked to complete a questionnaire 48 h after the end of the operation. In thecase of children, parents were asked to complete a similar questionnaire. The questions were related to pain experienced during the first 48 h after surgery and to the nature andseverity of postoperative complications. Results: A total of 1035 out of the 1100 patients returned the questionnaire, 94.1%. Overall the majority (65%) of patients had only mild pain at home; however, patients undergoing certain types of surgery had moderate-to-severe pain: inguinal hernia surgery (62% patients), orthopaedic surgery (41%), hand surgery (37%) and varicose vein surgery (36%). In these patients the severity of pain did not decrease during the 2-day study period. About 10% patients had more severe pain than they had anticipated, and 20% had difficulty in sleeping at night due to severe pain. Despite this, over 95% of patients were satisfied with man-agement of postoperative pain. Nausea (20%), tiredness (20%) and vomiting (8%) were the commonest complications reported during the first 48 h. A significant association was found between the administration of a general anaesthetic and the incidence of nausea postoperatively. A large number of patients were alone at home after the operation (28.4%); some (3.8%) had no access to a relative or friend in case of need. Conclusion: Our results show that about 35% of day-surgery patients experience moderate-to-severe pain at home in spite of analgesic medication. About 20% of patients had sleep problems due to severe pain. However, only 5% of patients were dissatisfied. Better analgesic techniques are necessary for patients undergoing certain types of surgery. Patient information and follow-up routines need to be improved.  相似文献   
120.
Pain following tonsillectomy is an important problem. It is caused by the surgical trauma of excision and haemostasis. Numerous surgical and pharmacological solutions have been tried, with disappointing results. Fibrin sealant is a widely used atraumatic haemostatic agent. This study aims to determine whether tonsillectomy with fibrin sealant haemostasis results in less post-operative pain than that with the conventional technique of diathermy. Fifty consecutive adult patients undergoing tonsillectomy were prospectively studied. They were randomized to receive either fibrin sealant or diathermy haemostasis. Other pain variables were controlled. Pain was measured by a visual linear analogue scale and inter-incisor distance on both the day of operation and the first post-operative day. The patients and pain measurer were blind to the randomization. The results showed that tonsillectomy with fibrin sealant haemostasis was significantly (P < 0.05) less painful than that with diathermy on both days studied and by both methods of pain measurement  相似文献   
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