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1.
Acupuncture analgesia (AA) caused by low frequency stimulation of the acupuncture point (AP) was abolished by hypophysectomy and adrenalectomy. Termination of the AA producing pathway from the AP to the pituitary gland was in the medial hypothalamic arcuate nucleus (M-HARN). The origin of the descending pain inhibitory system associated with AA was in the posterior HARN (P-HARN). AA in the hypophysectomized rats, and enhanced neuronal activity in the P-HARN that were abolished during acupuncture stimulation, were both restored by intraperitoneal microinjection of 0.5 mg/kg morphine or 0.1 micrograms beta-endorphin into the P-HARN during acupuncture stimulation. Of the analgesia produced by dopamine or beta-endorphin injected into the P-HARN, that caused by beta-endorphin disappeared after denervation of the M-HARN. The P-HARN neurons that responded to acupuncture stimulation also responded to iontophoretic dopamine, but not to iontophoretic morphine nor ultramicroinjected beta-endorphin. The transmission between the M-HARN and P-HARN may be dopaminergic, and beta-endorphin might presynaptically modulate this transmission. Reduction of sodium ions may have been the reason for abolition of AA after adrenalectomy. 相似文献
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3.
左旋布比卡因复合舒芬太尼或芬太尼在分娩硬膜外自控镇痛的应用 总被引:1,自引:0,他引:1
目的探讨左旋布比卡因复合舒芬太尼硬膜外自控镇痛(PCEA)用于分娩镇痛的临床效果及安全性。方法随机选择120例美国标准协会(ASA)I-Ⅱ级初产妇,随机分为舒芬太尼组(A组)、芬太尼组(B组)、无镇痛组(C组),每组40例。A组和B组采用PCEA,C组不给予镇痛药物。观察各组不同时段视觉模拟评分(VAS)和不良反应的发生,同时记录3组产程时间、分娩方式、缩宫使用情况、产后出血量、新生儿Apgar评分。结果A、B2组和C组在PCEA20、60min及宫口开全时VAS差异有统计学意义(P〈0.05);PCEA5min,A、B2组VAS差异有统计学意义(P〈0.05),2组Bromage评分、不良反应差异无统计学意义(P〉0.05)。3组产程时间、分娩方式、产后出血量、新生儿Apgar评分比较差异均无统计学意义(P〉0.05)。结论左旋布比卡因复合舒芬太尼或芬太尼用于分娩镇痛安全有效,对母婴无明显不良影响。 相似文献
4.
Summary A double-blind, placebo-controlled study has been made of the analgesic and respiratory effects of constant rate infusions
of meptazinol and morphine in 30 patients after abdominal surgery.
Group I received meptazinol, loading dose 50 mg followed by i.v. infusion 0.5 mg · kg−1 · h−1, Group II received morphine, loading dose 5 mg and then an infusion of 0.05 mg · kg−1 · h−1, and Group III received saline.
After recovery from inhalation anaesthesia (without opiates or a local anaesthetic) pain relief and chemoreceptor carbon dioxide
tolerance were assessed before and at various times after starting the analgesic infusion. A similar degree of pain relief
was found after 10 min in Groups I and II, which lasted until the end of observation period (20 h). Heart rate and systolic
and diastolic blood pressures were lower in Group II than in Groups I and III, and respiratory rate fell in Groups I and II.
After 6 h arterial carbon dioxide tensions (PaCO2) became significantly higher in Group II than Group III. The maximum percentage fall in mean tidal volume (VT) and expired minute volume (0VE) from the preinjection values was significant in Groups I and II. End-tidal carbon-dioxide (PETCO2) and PaCO2 were significantly higher after 20 h of infusion in Group II compared to Group I. The slope of 0VE/PETCO2 (<S>) was increased in Group I and it was significantly reduced in Group II. Analysis of derived variables, such as the CO2 intercept (CO2I) and minute ventilation at 7 kPa (0VE7), indicated a shift to the right of the slopes in Groups I and II, initially more so in Group I.
It is concluded that constant rate infusions of meptazinol and morphine were effective in providing postoperative pain relief.
However, their effects on the central regulation of respiration were different, as meptazinol did not impair CO2 sensitivity whereas morphine did. 相似文献
5.
6.
V W Ansanelli 《Lasers in surgery and medicine》1986,6(5):470-472
Review of the literature reveals little to no data regarding the use of the CO2 laser as a surgical modality in the local treatment of breast cancer. This study was undertaken to determine if the CO2 laser is a surgical improvement over the scalpel, influencing patient care during the surgical and postsurgical period. In the author's series, a total of 209 procedures were performed. Within this group, 105 cases were performed with CO2 laser and 104 cases performed with the scalpel. Biopsies were always performed as a separate procedure prior to definitive surgery. This study was not designed to compare cure rates, the medical follow-up period being 1 year. The results of this study demonstrate a significant improvement in patients' postoperative care, surgical technique, and hospital cost-effectiveness. 相似文献
7.
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
8.
9.
T.-H. ZHOU X.-H. REN D.-L. YIN Y.-L. WU M. Li C.-Z. Lu D.-C. Wu Y.-Q. Wu Y.-Q. PENG Y.-P. WANG L. MA G. PEI 《Acta anaesthesiologica Scandinavica》1997,41(8):1077-1079
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
10.
Background: Increasingly larger series of laparoscopic fundoplications (LF) are being reported. A well-documented advantage of the laparoscopic
approach is shortened hospital stay. Most centers report typical lengths of stay (LOS) for LF of 2–3 days. Our success with
LF with a LOS of 1 day led to an attempt at performing LF on an ambulatory basis.
Methods: Sixty-one consecutive patients with appropriate criteria for LF underwent surgery at our institution. Patients were counseled
by the authors as to the usual postop course and progression of diet. All patients received preemptive analgesia (PEA) consisting
of perioperative ketorolac and preincisional local infiltration with bupivicaine. Anesthetic management included induction
with propofol, high-dose inhalational anesthetics, minimizing administration of parenteral narcotics, and avoidance of reversal
of neuromuscular blockade. Immediate postop pain management included parenteral ketorolac and oral hydro- or oxycodone. All
patients were given oral fluids and soft solids after transfer from the recovery room to the postoperative observation unit.
Two patients were excluded from ambulatory consideration due to excessive driving distance from our hospital. Another two
were hospitalized for observation after experiencing intraoperative technical problems.
Results: Of 57 patients in whom same-day discharge was attempted, there were three failures requiring overnight hospitalization: All
were due to pain and nausea; one patient also suffered transient urinary retention. There were no adverse outcomes related
to early discharge, and there were no readmissions. One patient returned to the emergency room after delayed development of
urinary retention. Median time from conclusion of operation to discharge was less than 5 h. No patients expressed dissatisfaction
with early discharge on follow-up interview.
Conclusions: LF can be safely performed as an ambulatory procedure. Analgesic and anesthetic management should be tailored to minimize
nausea and provide adequate pain control.
Received: 1 April 1996/Accepted: 29 May 1997 相似文献