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31.
应用标准微电极技术,研究了关附甲素对豚鼠右心室乳头肌动作电位最大除极速率(Vmax)的频率依赖性抑制作用(RDB),并与美西律,奎尼丁,劳卡尼进行了比较. 在相同刺激间隔(300 ms),产生50%左右RDB的药物浓度下,美西律的RDB开始最快,其第2个Vmax所产生的抑制已占RDB的64%,奎尼丁,劳卡尼和关附甲素的RDB开始速率常数分别为每个动作电位0.165, 0.076和0.136. 美西律,奎尼丁,劳卡尼和关附甲素产生RDB的恢复时间常数分别为1.4, 9.0, 18.2和44.0 s,而且它们的恢复时间常数是不依赖于药物浓度而变化的,结果提示,关附甲素是一个慢动力学钠通道阻滞剂. 相似文献
32.
Charles V. Clark 《Documenta ophthalmologica. Advances in ophthalmology》1990,74(4):277-285
The results of systemic autonomic nerve function studies in patients with closed-angle glaucoma and ocular hypertension are reviewed. Autonomic neuropathy has been demonstrated in 58% of patients with closed-angle glaucoma and 42% of ocular hypertensive subjects, with significantly increased prevalence in ocular hypertensives with narrow iridocorneal angles. The implications are discussed, with particular reference to the pathogenesis of raised intraocular pressure. 相似文献
33.
Carlos Sala M.D. Eduardo García-Granero M.D. Ph.D. María J. Molina M.D. Jose V. García M.D. Salvador Lledo M.D. Ph.D. 《Diseases of the colon and rectum》1997,40(8):958-961
PURPOSE: Epidural anesthesia is believed to benefit colorectal anastomotic blood flow because of the sympathetic blockade it produces. Our purpose is to measure with tonometry the effect of epidural anesthesia on colorectal anastomotic oxygenation. PATIENTS AND METHODS: Fifteen patients operated on for rectal cancer (radical anterior resection) were monitored postoperatively using tonometers placed in the stomach (celiac trunk), transverse colon (superior mesenteric artery), and the anastomotic area during the operation. An epidural catheter was placed at L1-2, and on the first postoperative day, 8 ml of bupivacaine (0.25 percent) was administered. The anesthetic effect extended up to T-4. Intramucosal pH (pHi) at the three locations was measured before, during, and after the epidural blockade. RESULTS: Gastric and transverse colon pHi increased during the epidural blockade from 7.35±0.01 to 7.41±0.01 and from 7.34±0.02 to 7.40±0.02, respectively. The anastomotic pHi decreased from 7.3±0.02 to 7.24±0.03 under the epidural and increased up to 7.34±0.02 after withdrawal of the effect on the following day. All pHi variations were statistically significant (P<0.05, paired Student'st-test and Wilcoxon's test), because it was the comparison between gastric and transverse colon pHi with the anastomotic pHi during the epidural (P<0.05, one-way analysis of variance and Kruskal-Wallis tests). None of the patients developed anastomotic or other complications. CONCLUSIONS: Epidural anesthesia with bupivacaine causes a significant decrease in the oxygenation-perfusion state of colorectal anastomosis in comparison with the increase in other areas of the digestive tract. Further studies need to be done to see if other epidural anesthetic-analgesic protocols also worsen colorectal anastomotic blood flow.Supported in part by a grant from the Spanish Society of Digestive Diseases, Madrid, Spain. All tonometric catheters and drugs were donated by the Clinic University Hospital of Valencia, Spain.Read at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996. 相似文献
34.
MRI诊断腰椎间盘术后粘连和突出复发 总被引:2,自引:0,他引:2
失败的下腰椎手术是个复杂的问题,由于其症状和体征不典型,单靠临床检查很难明确诊断,而脊髓造影和常规CT等检查也很难区别突出复发和硬膜外粘连。本文分析了32例再手术患者MRI图象,并与第二次手术所见对比,发现27例MRI诊断准确,3例假阳性,2例因信号缺失不能明确诊断。 相似文献
35.
BACKGROUND CONTEXT: Paraspinal infections after zygapophyseal (facet) radiofrequency denervation (RFD) are a serious but rare complication of this procedure. We are aware of only one case report of an epidural abscess after facet joint injection. PURPOSE: To report post-procedure inflammatory changes after cervical facet RFD. STUDY DESIGN: Case report. PATIENT SAMPLE: A 35-year-old Caucasian female. METHODS: Retrospective case review. RESULTS: The patient underwent cervical RFD and was admitted to the hospital 7 days after her procedure with severe neck pain. Magnetic resonance imaging (MRI) with contrast revealed what appeared to be evidence of a paraspinal muscle abscess although blood tests were negative. She was treated with antibiotic therapy, yet she never developed systemic signs of infection. A follow-up MRI without contrast revealed no evidence of infection, and she was discharged home on hospital day 6. At her first follow-up visit, she was still experiencing scalp pain and paraspinal muscle spasm. During subsequent follow-up visits, she has continued to improve clinically without experiencing signs of infection. Another follow-up MRI 6 weeks after her discharge home revealed persistent minimal left paraspinal enhancement at C2-3, possibly representing post-procedure granulation tissue with no evidence of abscess. CONCLUSIONS: Post-procedural MRI findings after radiofrequency lesioning can resemble radiographic findings associated with a paraspinal abscess. Patients with radiographic findings consistent with abscess should only be treated if clinical signs or symptoms of systemic infection are present. 相似文献
36.
37.
ATILLA EROL SEMA TUNCER AYBARS TAVLAN RUHIYE REISLI GÖKHAN AYSOLMAZ SEREF OTELCIOGLU 《Pediatrics international》2007,49(6):928-932
BACKGROUND: The aim of the present randomized study was to determine the effect of adding sufentanil to bupivacaine, compared with bupivacaine alone in caudal block, on the surgical stress response in children. METHODS: The children were premedicated with midazolam 0.5 mg/kg. All children received induction with nitrous oxide and sevoflurane. Anesthesia was maintained with the same volatile agents in the both groups. The children were randomly allocated to two groups. Group I received bupivacaine alone (n = 17) and group II received bupivacaine + sufentanil (n = 16). Caudal block was performed with 0.25% bupivacaine 2 mg/kg (group I) or 0.25% bupivacaine 2 mg/kg with sufentanil 0.5 microg/kg (group II) after induction of anesthesia. Blood samples were obtained after induction of anesthesia (T(0)) to measure baseline concentrations of cortisol, prolactin, glucose and insulin. Additional samples were obtained 30 min after the start of surgery (T(1)), and 60 min after the end of surgery (T(2)). RESULTS: All of the basal values (T(0)) were within the normal ranges of the authors' laboratory for children of this age group and there were no differences between the groups (P > 0.05). In both groups, glucose concentration increased at T(1), compared with T(0) and T(2) (P < 0.05). The glucose concentration was unchanged at T(2) compared with T(0) in both group (P > 0.05). In both groups, prolactin concentration increased at T(1), compared with T(0) and decreased at T(2), compared with T(1) (P < 0.05). Cortisol decreased at T(1) and T(2), compared with T(0) in both groups. (P < 0.05). Insulin concentration remained unchanged at T(0) and T(2), but increased slightly at T(1) in both groups (P > 0.05). There were no significant differences in plasma prolactin, cortisol, glucose and insulin levels between the two groups at T(1) and T(2) (P > 0.05). CONCLUSION: There is no advantage in adding 0.5 microg/kg sufentanil to bupivacaine over bupivacaine alone in the caudal block, with regard to the surgical stress response in children. 相似文献
38.
Somboon Thienthong Wimonrat Krisanaprakornkit Duenpen Horatanaruang Panaratana Yimyam Bandit Thinkhamrop Jariya Lertakyamanee 《Acute Pain》2004,6(1):15-21
We compared rates of motor blockade, analgesia, adverse effects and patient satisfaction of 0.1% ropivacaine+fentanyl versus 0.2% ropivacaine-alone in a randomized, controlled trial. Fifty-four women who had undergone abdominal hysterectomy were randomly allocated into two groups to receive an epidural block at L1–2 or L2–3: group R received 0.2% ropivacaine-alone and group RF received 0.1% ropivacaine plus 2 μg fentanyl/ml, both at 8 ml/h. Rescue analgesia was provided via a morphine-loaded PCA device. Motor blockade (using a modified Bromage scale), pain intensity (visual analogue scale (VAS)), morphine consumption, level of sensory blockade and adverse effects, were measured at 4, 8 and 21 h after infusion. Patient satisfaction with pain management was assessed at the end of the study. The rates of motor blockade were not different at 8 h after infusion but at 21 h, group RF had significantly less motor blockade than group R. There were no differences in VAS, level of sensory blockade, adverse effects and patient satisfaction. Morphine consumption at each measurement was comparable but the total amount used by group RF was less than group R (12 mg versus 20 mg, P=0.049). Therefore, 0.1% ropivacaine with fentanyl 2 μg/ml appears to offer advantages over 0.2% ropivacaine-alone. 相似文献
39.
M Kühne B Schaer C Kaufmann N Moulay T Cron T Cueni P Weiss C Schindler C Sticherling S Osswald 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(12):1185-1190
AIMS: DDD-pacemakers are favoured in patients with sick-sinus-syndrome or AV-block. However, AAI-pacemakers for sick-sinus-syndrome or VDD-pacemakers for AV-block may provide similar benefit with lower costs. The aim is to show that a tailored approach (TA) with arrhythmia-specific pacemaker selection was equal to a standard approach (SA) regarding quality of life (QoL) at lower costs. METHODS AND RESULTS: The study was prospective and randomized with QoL as primary endpoint. Secondary endpoints were a combined endpoint of all-cause mortality, worsening heart failure or angina, atrial fibrillation (AF), stroke, these endpoints individually and costs. Of 198 patients (age 77 +/- 10 years, 43% female, ejection fraction 54 +/- 12%, follow-up 38 +/- 15 months), 94 were randomized to SA and 104 to TA. Thirty-two patients (34%) died in the SA group vs. 25 (24%) in the TA (P= ns). QoL showed no differences in all dimensions. The combined secondary endpoint was reached more frequently with SA (51%) compared to TA (37%, P = 0.045). There was no difference regarding all single secondary endpoints. Hardware costs were reduced by 15% (P < 0.0001). CONCLUSION: In long-term follow-up, a TA is equal to SA regarding the primary endpoint QoL and secondary endpoints as AF and mortality. Depending on the healthcare system, it may significantly reduce costs. 相似文献
40.
Kulbir S. Walia MD ; Daniel E. Muser MD ; Shariq S. Raza MD ; Tricia Griech MSPT ; Yasin N. Khan MD 《Pain practice》2004,4(4):303-306
Abstract: We present a case of a 13-year-old boy who developed signs and symptoms of neuropathic pain/early Complex Regional Pain Syndrome (CRPS) Type I, formerly known as Reflex Sympathetic Dystrophy (RSD), after spraining his ankle while wrestling. Aggressive pain control, using medications and sympatholytic blocks, with physical therapy and rehabilitation, led to the resolution of his painful condition. This prevented the disease from possibly progressing to a full-blown case of CRPS I (RSD) that is very challenging to treat. 相似文献