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31.
David C. S. Roberts 《Psychopharmacology》1993,111(2):202-206
Intravenous self-administration of GBR 12909, an indirect dopamine agonist, was examined on a Fixed Ratio (FR 1) and a Progressive Ratio (PR) schedule of reinforcement in rats. Subjects were first trained to self-administer cocaine (1.5 mg/kg/inj) during daily 5 h sessions, after which GBR 12909 (0.187–1.5 mg/kg/inj) was substituted. On the FR 1 schedule, the inter-infusion interval for GBR 12909 self-administration was directly related to dose and was approximately three times longer than that established for equivalent doses of cocaine. Breaking points on the PR schedule were comparable for GBR 12909 and cocaine self-administration. The data indicate that, compared to cocaine, GBR 12909 has a longer duration of action and a similar reinforcing efficacy. 相似文献
32.
本文采用俯卧拍背法缓解胆绞痛41例,其中23例经此法治疗后疼痛立即消失(56.1%);15例明显缓解(36.6%);3例缓解不明显(7.3%)。具有操作简便、安全,易被患者接受,值得推广。 相似文献
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Levodopa improves physical fatigue in Parkinson's disease: a double-blind, placebo-controlled, crossover study. 总被引:1,自引:0,他引:1
Jau-Shin Lou Greg Kearns Theodore Benice Barry Oken Gary Sexton John Nutt 《Movement disorders》2003,18(10):1108-1114
We quantitatively investigated the effect of carbidopa/levodopa (25/100) on physical fatigue during finger tapping and force generation in a double-blind, placebo-controlled crossover study. Parkinson's disease (PD) subjects were randomly assigned to carbidopa/levodopa or placebo for Visit 1 or 2 and participated in the following two studies: (1) Finger tapping. Twenty-five PD patients used their index fingers to strike two keys 20 cm apart on a musical instrument digital interface (MIDI) keyboard. The slopes of the regression line of dwell time and movement time were used to assess the rate of fatigue development. (2) Force generation. Twelve PD patients contracted the wrist extensors maximally to obtain a baseline maximum voluntary contraction (BMVC) force. Then they repetitively contracted the wrist extensors at 50% of the BMVC for 7 seconds and rested for 3 seconds. An interval maximum voluntary contraction (IMVC) was measured every three repetitions. Fatigue was defined as an IMVC of less than 60% of the BMVC. The slope of the regression line of IMVC was used to assess the rate of force decline. These two studies were repeated 1 hour after carbidopa/levodopa (25/100) or placebo. Subjects filled out the Multidimensional Fatigue Inventory (MFI) at the beginning of the first visit. Results showed that the slope of dwell time decreased with levodopa but not with placebo (P = 0.004). The rate of force decline also decreased with levodopa but not with placebo (P = 0.01). The subscores in the dimension of physical fatigue in the MFI did not correlate with the rate changes in dwell time or the rate changes in force decline. We concluded that (1) levodopa improves physical fatigue in finger tapping and force generation, (2) physical fatigue in Parkinson's disease is at least partially related to dopamine deficiency, and (3) the MFI measures different aspects of physical fatigue compared with those measured by finger tapping and force generation. 相似文献
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36.
选择62例拔除第一双尖牙的样本,分为平弓丝组、带“U”型阻滞曲组、固定舌弓组,采用方丝弓细丝弓技术,以磨牙作支抗拉尖牙向远中移动,对支抗磨牙进行观察。为期4周的观察发现,平弓丝组、带“U”型阻滞曲组的支抗磨牙均有近中舌向扭转,第二双尖牙中央窝间距亦比治疗前减少;而固定舌弓组支抗磨牙未见有近中舌向扭转。作者认为:以磨牙为支抗移动尖牙时,应注意支抗控制。本文对力的使用及支抗失控的预防、处理问题进行了讨论。 相似文献
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38.
目的 通过问卷调查表对患者戴用附着体义齿后的主观感受进行研究.方法 选择上下牙列缺损患者42例,共制作带塑料插入件栓式附着体义齿47例,于戴牙后1个月,患者基本适应戴用义齿,通过问卷调查,了解患者戴用义齿后的适应情况、对义齿的满意程度及咀嚼功能的变化等.结果 患者对带塑料插入件栓式附着体义齿和传统可摘局部义齿两种修复方式比较,在总的满意度、美观、舒适、咀嚼、语言、适应期、食物结构改变等方面,前者明显优于后者,差异有统计学意义.结论 带塑料插入件栓式附着体义齿在美观及功能上不仅能满足患者的要求,而且远优于传统可摘局部义齿. 相似文献
39.
YASUMASA SHICHIRI NORIYASU TAKAO TOMOYUKI OIDA HIROSHI KANAMARU YOSUKE SHIMIZU 《International journal of urology》2004,11(11):1019-1023
The most serious problem regarding a laparoscopic partial nephrectomy is how to perform bloodless excision without causing renal ischemia in a limited working space. We report the case of a 65-year-old man with left small renal cell carcinoma in the posterior mid zone who underwent a laparoscopic partial nephrectomy through a retroperitoneal approach by carrying out the ligation of the tumor-feeding artery, but without clamping the renal pedicle. Both preoperative abdominal computed tomography (CT) and intraoperative ultrasonography revealed the tumor to be fully encapsulated. The tumor-feeding artery could be exposed by dissection from the renal hilum and, after an arterial ligation, tumor resection with a safety margin was smoothly performed with minimal bleeding. Postoperatively, CT revealed a limited defect of the renal parenchyma and excretory pyelography showed no urine leakage or urinary tract obstruction. The preoperative and postoperative creatinine levels were 0.66 and 0.69 mg/dL, respectively. As a result, a tumor-feeding artery ligation with a laparoscopic partial nephrectomy for left renal cell carcinoma in the posterior mid zone is considered to be an effective surgical modality which avoids renal ischemia and pelvic heat injury. 相似文献
40.
Ictal brain imaging in presurgical evaluation of patients with medically intractable complex partial seizures 总被引:1,自引:0,他引:1
O. N. Markand V. Salanova R. M. Worth H.-M. Park H. H. Wellman Omkar N. Markand M.D 《Acta neurologica Scandinavica》1994,89(S152):137-144
At the Indiana University Medical Center, 99 patients with medically intractable complex partial seizures (MI-CPS) had presurgical evaluation with subsequent anterior temporal lobectomy. The majority of the patients had single photon emission tomography (SPECT) performed interictally as well as during an actual epileptic seizure (ictal scan). Decreased regional cerebral perfusion (rCP) was seen in 54/94 (57%) of the interictal scans corresponding to the eventual site of the surgery. However, ictal scans provided a higher yield; increased rCP in the temporal lobe during an actual seizure was observed in 60/82 (73%) concordant to the side of surgery. SPECT is a useful, noninvasive method of localizing the epilepti-form focus in patients with MI-CPS considered for resective surgery. Both interictal and ictal SPECT need to be performed; combined interictal hypo-perfusion and ictal hyperperfusion in the same focal area are unique to epileptogenic lesions. Ictal SPECT studies can be performed in the majority of patients during the period of continuous video/EEG monitoring with only a little additional effort. Combining the results of functional brain imaging (interictal and ictal SPECT, PET) with clinical semiology of seizures, surface and sphenoidal EEG, magnetic resonance imaging and other non-invasive tests, anterior temporal lobectomy can be recommended in approximately two-thirds of the patients without resorting to potentially dangerous intracranial EEG monitoring. 相似文献