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101.
A review of serotonin toxicity data: implications for the mechanisms of antidepressant drug action. 总被引:2,自引:0,他引:2
P Ken Gillman 《Neuropsychopharmacology》2006,59(11):1046-1051
Data now exist from which an accurate definition for serotonin toxicity (ST), or serotonin syndrome, has been developed; this has also lead to precise, validated decision rules for diagnosis. The spectrum concept formulates ST as a continuum of serotonergic effects, mediated by the degree of elevation of intrasynaptic serotonin. This progresses from side effects through to toxicity; the concept emphasizes that it is a form of poisoning, not an idiosyncratic reaction. Observations of the degree of ST precipitated by overdoses of different classes of drugs can elucidate mechanisms and potency of drug actions. There is now sufficient pharmacological data on some drugs to enable a prediction of which ones will be at risk of precipitating ST, either by themselves or in combinations with other drugs. This indicates that some antidepressant drugs, presently thought to have serotonergic effects in animals, do not exhibit such effects in humans. Mirtazapine is unable to precipitate serotonin toxicity in overdose or to cause serotonin toxicity when mixed with monoamine oxidase inhibitors, and moclobemide is unable to precipitate serotonin toxicity in overdose. Tricyclic antidepressants (other than clomipramine and imipramine) do not precipitate serotonin toxicity and might not elevate serotonin or have a dual action, as has been assumed. 相似文献
102.
The subthalamic nucleus (STN) is a major target for treatment of advanced Parkinson's disease patients undergoing deep brain stimulation surgery. Microelectrode recording (MER) is used in many cases to identify the target nucleus. A real-time procedure for identifying the entry and exit points of the STN would improve the outcome of this targeting procedure. We used the normalized root mean square (NRMS) of a short (5 seconds) MER sampled signal and the estimated anatomical distance to target (EDT) as the basis for this procedure. Electrode tip location was defined intraoperatively by an expert neurophysiologist to be before, within, or after the STN. Data from 46 trajectories of 27 patients were used to calculate the Bayesian posterior probability of being in each of these locations, given RMS-EDT pair values. We tested our predictions on each trajectory using a bootstrapping technique, with the rest of the trajectories serving as a training set and found the error in predicting the STN entry to be (mean +/- SD) 0.18 +/- 0.84, and 0.50 +/- 0.59 mm for STN exit point, which yields a 0.30 +/- 0.28 mm deviation from the expert's target center. The simplicity and computational ease of RMS calculation, its spike sorting-independent nature and tolerance to electrode parameters of this Bayesian predictor, can lead directly to the development of a fully automated intraoperative physiological procedure for the refinement of imaging estimates of STN borders. 相似文献
103.
104.
红斑反应与理想光子嫩肤术关系的研究 总被引:1,自引:0,他引:1
目的 观察红斑反应与理想光子嫩肤术的关系,为临床提供参考.方法 采用34 J/cm2的强脉冲光,对10只兔子(4个部位)分别照射1、2、3、4次,记录出现红斑反应的照射次数,术后第15天观察治疗部位切片,记录使皮肤真皮胶原蛋白增生的照射次数.结果 红斑反应的阈刺激照射次数是(2.60±0.52)次,真皮胶原蛋白增生的阈刺激照射次数是(3.00±0.67)次.两者比较无显著差异.结论 IPL致红斑反应的能量大小,与理想光子嫩肤术所需的能量接近. 相似文献
105.
TSUTOMU NOMURA KAZUHIDE HIGUCHI HIDENORI YU SHIN-ICHI SASAKI SHUJI KIMURA HIROYUKI ITOH MICHIYO TANIGUCHI TETSUO ARAKAWA KOKI KAWAI 《Journal of gastroenterology and hepatology》2006,21(1):54-58
Background and Aim: Although pretreatment with a sedative drug is effective in relieving pain during esophagogastroduodenoscopy (EGD), such drugs can cause significant side‐effects. The aim of this study was to examine the effect of slow‐wave photic stimulation on discomfort and/or pain felt during EGD. Methods: Forty consecutive patients (25 men and 15 women) who underwent diagnostic EGD in our hospital were included in the study. Twenty patients received photic stimulation for 25 min, and underwent electroencephalographic recording, in addition to the usual premedications. Twenty control patients received the same treatment but without photic stimulation. All patients evaluated the discomfort/pain felt during endoscopy against a five‐grade scale in comparison with what they had experienced in their previous examination. Results: Patients with an improved discomfort/pain score were 18/20 and 3/20 in the treated and control groups, respectively. Overall comparison of pain scores between both groups was significant (P < 0.0001). The proportion of slow‐wave activity recorded in patients’ electroencephalograms significantly increased in the treated group compared to control values (36.6 ± 6.8% vs 29.1 ± 3.4%, P < 0.001). There was a close correlation between the degree of discomfort/pain felt during endoscopy and the proportion of slow‐wave activity (P < 0.001). Conclusion: Slow‐wave photic stimulation shows promise as a treatment for relieving the discomfort and/or pain felt by patients undergoing EGD. 相似文献
106.
目的 从福参Angelica morii提取分离活性成分。方法 采用乙醇提取,溶剂萃取,大孔树脂、聚酰胺、硅胶柱层析,LH-20、重结晶等纯化,对福参饮片进行系统提取分离;运用波谱学方法及理化常数对照进行结构鉴定。结果 从正丁醇和水部分分离到6个苷类化合物,分别为升麻索苷(prim-O-glucosylcimifugin,Ⅰ)、紫花前胡苷(marmesinin,Ⅱ)、芹菜素7-O-β-D-葡萄糖苷(apigenin 7-O0-β-D-glucoside,Ⅲ)、木犀草素7-O-β-D-葡萄糖苷(1ute—olin 7-O-β-D-glucoside,Ⅳ),umbeliferone 7-apiosylglucoside(V)和胡萝卜苷(daucosterol,Ⅵ)。结论 6个化合物均为首次该植物中分得;化合物Ⅲ首次从当归属中分得。 相似文献
107.
Scott Lozanoff Barbara A. Long David L. Singer John J. Deptuch 《Journal of clinical periodontology》1992,19(8):553-559
Deposits of dental plaque or calculus are typically quantified using planimetric techniques. However, error is introduced into a quantitative analysis of plaque deposits using these methods, since they require a significant amount of human intervention. The purpose of this study is to describe and validate a computerized imaging routine which has the potential to objectively identify material on dental roots and measure the area covered by these deposits. Dentiform teeth with simulated plaque were videorecorded. A computer routine was developed based on a flood-fill algorithm which analyzed images of the dentiform teeth and determined the amount of simulated plaque on their root surfaces. Results showed that the dentiform teeth and their simulated plaque patterns are duplicated by the imaging routine in a rapid and reliable fashion. The system shows a high degree of accuracy with an average error factor of only 0.58%. As well, the system enables precise reproducibility with an average error factor of only 0.71%. 相似文献
108.
Objective. Neurally augmented sexual function (NASF) is the production of pleasurable genital stimulation and subsequent orgasm through the application of electrical energy to provide stimulation of the spinal cord or peripheral nerves. The purpose of this paper is to demonstrate the reproducibility of this phenomenon. Materials and Methods. Eleven otherwise healthy women, ages 32–60 years, were selected for this study. Through standard techniques, quadripolar (octopolar in the final patient) leads were placed in the epidural space percutaneuously. The lead was maneuvered initially to an L1–L2 position and then repositioned based on feedback from the patient. The patients were allowed to utilize the device ad libitum for up to 9 days. Results. Successful stimulation was achieved in 91% (10/11) of patients. These women described a greater frequency in sexual activity, increased lubrication, and overall satisfaction. A smaller subset had substantial improvement in sexual function as measured by orgasmic capacity. This subset consisted of women with secondary anorgasmia. A return of orgasmic capacity was found in 80% (4/5) of patients having secondary anorgasmia with an average intensity of ≥ 3/5 while using the device. Once the device was removed, the patients returned to their previous anorgasmic status. Conclusions. Pleasurable genital stimulation of the spinal cord is a consistently reproducible phenomenon. In a subset of the population studied, improvement in orgasmic function was noted. This was noted in the group with secondary orgasmic dysfunction. 相似文献
109.
We present a case of a female patient suffering from type I complex regional pain syndrome (CRPS) who developed “mirror imaging” of her CRPS and was successfully treated with dual spinal cord stimulation (SCS) in the paraforaminal epidural space. This patient initially had unilateral pain that was unsuccessfully treated with midline SCS and single‐lead lateral epidural lead placement “paraforaminally.” One year later, because we believed that paraforaminal stimulation would preferentially stimulate primary sensitized afferents innervating the painful area, we reperformed SCS with two leads positioned laterally and paraforaminally close to the roots within the epidural space. After repositioning and after 1 year of paraforaminal stimulation, there was significant improvement in the patient's symptoms, resolving all unilateral and “mirrored” symptoms. We conclude that paraforaminal stimulation may be a valid therapeutic option for the treatment of CRPS. 相似文献
110.
F Gilio A Currà M Inghilleri C Lorenzano M Manfredi Alfredo Berardelli 《Movement disorders》2002,17(3):467-473
We investigated the neurophysiological and clinical effects of repetitive magnetic stimulation (rTMS) delivered to the cortical motor areas in healthy subjects and patients with Parkinson's disease. rTMS was delivered with a high speed magnetic stimulator (Cadwell, Kennewick, WA) through a figure-eight coil centred on the primary motor area at a stimulus intensity of 120% motor threshold. Trains of 10 stimuli were delivered at frequencies of 5 Hz while subjects were at rest and during a voluntary contraction of the contralateral first dorsal interosseous muscle. In normal subjects at rest, the muscle evoked responses (MEPs) to each stimulus in a train of magnetic stimuli progressively increased in size during the train. rTMS left the MEPs unchanged in patients off therapy and had a small facilitatory effect in those on therapy. In normal subjects and patients, 5-Hz rTMS trains delivered during a voluntary contraction of the target muscle left the MEP unchanged in size. MEPs were followed by a silent period that increased in duration during the course of the train. The silent period duration increased to a similar extent in patients and controls. The reduced rTMS-induced facilitation of MEPs in patients with Parkinson's disease reflects a decreased facilitation of the excitatory cells in the cortical motor areas. 相似文献