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21.
Alterations of gamma aminobutyric acid (GABA)-mediated neurotransmission have been implicated in the pathogenesis of epilepsies. Here we examine the distribution of the GABAA receptor in the hippocampus of 78 surgical specimens from patients with chronic pharmacoresistant focal epilepsies. The receptor was localized immunohistochemically with the monoclonal antibody bd-24 which selectively recognizes the 1 subunit of the GABAA receptor. The results were compared with the receptor distribution of 28 normal hippocampal specimens obtained at autopsy. In the great majority of the surgical specimens a loss of GABAA receptor immunoreactivity was present in CA1 (92.3%), CA4 (78.2%), the dentate granular cell layer (70.5%) and the molecular layer of the dentate gyrus (65.4%). The subiculum revealed a normal staining pattern in all but 4 cases. In no instance did we observe an increase of immunoreactivity in any region or cell population. The decrease of GABAA receptor immunoreactivity was closely related to neuronal loss in the respective specimen and to Ammon's horn sclerosis. There was no correlation between GABAA receptor loss and the patient's age at surgery, duration of seizures, age at onset of seizures and to the presence or absence of secondary generalized tonic clonic seizures. The data suggest that the observed loss of GABAA receptor immunoreactivity is a secondary phenomenon rather than an event that is relevant for the pathogenesis of epileptic seizures.  相似文献   
22.
伽玛刀的医学技术评估   总被引:9,自引:0,他引:9  
伽玛刀是世界上最昂贵的医疗设备之一,我国从1992年开始引进。1995年卫生部等联合发文暂缓装备。为了规范提供方和患方的行为,以及为卫生行政部门提供决策依据,我们开展了伽玛刀的技术评估。在评估前拟定评估步骤,然后确定评估内容与方法。评估结果,国外1994年有56台伽玛刀,平均每台治疗190例,治疗病种是:动静脉畸型病人占32%,肿瘤病人占65%,功能性疾病占2%。我国13台伽玛刀到1995年底共治病人7000例,前6位病种是转移瘤等,虽然比例和顺位与世界有差异,但病例分析结果完全一致。  相似文献   
23.
Measurement of individual kidney glomerular filtration rate (IKGFR) from the gamma-camera technetium 99m diethylene triamine penta-acetic acid (99mTc-DTPA) renogram requires a continuous measurement of arterial activity. This is usually based on a region of interest (ROI) placed over the cardiac blood pool on the posterior view, with the assumption of negligible contamination from activity in the extravascular space of the chest wall. By injecting a small dose of technetium 99m human serum albumin (HSA) before the99mTc-DTPA in 12 patients undergoing routine renography, the contribution of extravascular activity to the total signal recorded over the cardiac blood pool was calculated to be 11.0% (SE 2.1%) 1.5 min after DTPA injection, rising to 35.1% (SE 2.5%) at 15 min. Subtraction of the time-activity curve recorded from a ROI of the same size over the right lung generated a pure blood signal as shown by almost identical HSA/DTPA signal ratios recorded in blood samples taken 5 min after HSA and 15 min after DTPA and from the gamma-camera at the corresponding times. The effect of using a cardiac blood pool time-activity curve uncorrected for extravascular activity was to overestimate IKGFR by an average factor of 1.17 (SE 0.03). Offprint requests to: A.M. Peters  相似文献   
24.
伽玛刀治疗后的肿瘤内出血   总被引:4,自引:0,他引:4  
目的:探讨颅内肿瘤患者伽玛刀治疗后肿瘤内出血的原因。方法:在伽玛刀治疗的345例颅内肿瘤病变患者中,发现3例有肿瘤内出血,分析了他们的临床特点及CT,MRI表现,结果:2例经保守治疗基本痊愈,1例恶化。结论:对于那些曾有过肿瘤卒中史、高血压病史或肿瘤血运丰富的病人行伽玛刀治疗后应警惕发生肿瘤内出血的危险  相似文献   
25.
Gamma Surgery for Hemangiopericytomas   总被引:6,自引:0,他引:6  
A retrospective analysis of a consecutive series of 12 patients with 15 intracranial hemangiopericytomas treated at the University of Virginia using Gamma surgery is presented. Clinical and radiographic follow up of 3 to 56 months is available for 10 patients with 12 tumors. There was one tumor present at the time of initial Gamma surgery in each patient. Two new tumors occurred in patients previously treated. Nine of the tumors decreased in volume and three remained stable. Four of the nine tumors that shrank later progressed at an average of 22 months after treatment. Of the tumors that decreased in volume and have not progressed, the response has been for an average of 11 months. The follow-up for two tumors that remained unchanged was 10 and 34 months (average 22 months). A third tumor was unchanged at 42 months but the patient died of new disease adjacent to the treated area in the anterior skull base. There were no complications and the quality of life following the procedure was maintained or improved in every case. Gamma surgery is effective in palliating the patients by decreasing tumor volume and delaying recurrence.  相似文献   
26.
目的:从一个侧面探讨伽玛刀的作用地位。方法:采取“伽玛刀”和“开颅手术”两治疗方法对垂体腺瘤治疗的住院日、治疗率、后续治疗率,以及病人收治数量的变化等方面进行对比分析。结果:在239例垂体腺瘤的治疗中,伽玛刀治疗的平均住院日只是开颅手术的31.40%,治疗率占64.85%,后续治疗率2、58%(开颅手术为38.10%),病人收治数量明显增加。结论:伽玛刀在医疗绩效中的作用明显。  相似文献   
27.
目的:探讨彩色多普勒超声检查肝癌经伽玛刀(-γ刀)治疗效果的价值。方法:32例原发性肝癌患者37个肿块,-γ刀治疗前及治疗后1周、1个月、3个月、6个月运用彩色多普勒超声进行随访。结果:-γ刀治疗后1周~1个月,肝癌病灶表现为稳定,3~6个月,病灶表现为显效,且肿块越小,治疗效果越好。结论:-γ刀治疗肝癌,是一种体外无创性的放疗方法,近期疗效满意。彩超的检查结果与临床随访相符。彩超可望成为肝癌-γ刀治疗后的观测疗效及指导治疗的有效方法。  相似文献   
28.
The fate (movement and disintegration) of hard novel hydroxypropyl methylcellulose (HPMC) two-piece capsules in the human gastrointestinal tract was investigated using a gamma scintigraphic imaging method. Two different prolonged-release formulations without an active ingredient were used. The capsules contained different viscosity grades of HPMC powder (HPMC K100 and HPMC K4M). The aim was to determine the main reason why the pharmacokinetic profiles of model drugs change when the diluent was changed to a higher viscosity grade. The results were compared with our previous pharmacokinetic studies with corresponding capsules containing metoclopramide hydrochloride or ibuprofen as a model drug. The first observation was that the HPMC capsules had a tendency to attach to the oesophagus. Therefore, it is recommended that the HPMC capsules as well as gelatine capsules be taken with a sufficient amount of water (150–200 ml) in an upright position and maintaining the upright position for several minutes. The viscosity grade of the HPMC did not affect the transit times of the capsules in the GI tract. The major differences between the two formulations were the complete disintegration times of the capsules and the spreading of the capsules to the large intestine. Most of the HPMC K100-based capsules were completely disintegrated during the 8 h study, whereas the HPMC K4M-based capsules still exhibited plug formations in the large intestine. Also the HPMC K100-based capsules spread better to the ascending colon than the HPMC K4M-based capsules. The faster disintegration of the HPMC K100-based capsules explains the differences in the pharmacokinetic profiles of the model drugs between the HPMC K100- and K4M-based capsules in our previous studies. The main absorption site of the drugs from the capsules studied here is probably the large intestine when taken in a fasting state.  相似文献   
29.
Complementary statistical analyses are performed on data concerning tracheal reconstruction in rats. The principal response criterion is vessel area as defined by the area of a graft onto the trachea covered by blood vessels. Postoperatively, this vessel area changes in a nonlinear fashion over time. Starting at 0% immediately postoperation, the vessel area increases to a peak and then sharply decreases to a certain level at which it remains. A total of 64 independently observed cross-sectional pairs (postop day, vessel area) are distributed among four treated groups. Analysis consists of two-way analysis of variance and piecewise linear regression under the usual assumptions of normality and variance homogeneity. Other analyses that relax these assumptions are also considered; treatment differences are established by nonparametric tests, and a quasi-likelihood analysis of the piecewise linear regression model is applied under the assumption of a binomial-like variance function. The resulting fit of the normal-theory-based piecewise linear model is compared to that of a nonlinear model whose shape is that of a gamma function integrand.  相似文献   
30.
《Injury》2016,47(12):2733-2738
IntroductionPoor bone quality and unstable fractures increase the cut-out rate in implants with gliding lag screws. The U-Blade (RC) lag screw for the Gamma3® nail was introduced to provide monoaxial rotational stability of the femoral head and neck fragment. The purpose of this study was to evaluate whether the use of the U-Blade (RC) lag screw is associated with reduced cut-out in patients with OTA/AO 31A1-3 fractures.Material & methodsBetween 2009 and 2014, 751 patients with OTA/AO 31A1-3 fractures were treated with a Gamma3® nail at our institution. Out of this sample 199 patients were treated with U-blade (RC) lag screws. A total of 135 patients (117 female, 18 male) with standard lag screw (treatment group A) were matched equally regarding age (±4 years) sex, fracture type and location to 135 patients with U-blade (RC) lag screw (treatment group B). Within a mean follow up of 9.2 months (range 6–18 months) we assessed the cut-out rate, the calTAD, lag screw migration, the Parker's mobility score and the Parker’s ratio at postoperatively, six and 12 months following surgery. Furthermore we recorded all complications, ASA-Score, hospital stay and duration of surgery retrospectively.ResultsThe most common fracture among group B with a cut-out of the lag screw were AO/OTA 2.3 and 3.2 fractures whereas in group A cut-out was most commonly seen in AO/OTA 2.1, 2.2 and 2.3 fractures, there was no significant reduction of the cut-out rate in group B 2.2% (n = 3) compared to group A 3.7% (n = 5). The duration of surgery was significantly shorter in group A (p < 0.05). There was no significant difference in lag screw placement, the Parker’s ratio and mobilization.ConclusionIn our study the U-Blade (RC) lag screw did not reduce the cut-out in treatment of OTA/AO 31A1-3 fractures at all. Considering the longer duration of surgery and the higher costs of the U-Blade (RC) lag screw, our results do not justify its use. However, further prospective randomized studies will be necessary.  相似文献   
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