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61.
目的 探 讨极 外 型腰 椎间 盘 突出 症患 者 的临 床特 点 与神 经节 位 置的 相关 性 方 法:通过 术前 神 经根 造影 : 。确定 受压 神 经根 的背 根 神经 节的 位 置,根 据 其神 经节 的 位置 ,将 27 例极 外侧 腰 椎间 盘突 出 症患 者 分为 三 组 :椎管内 组,5 例;椎间 孔内 组 ,15 例 ;椎 间孔 外组 ,7 例 。分 别比 较神 经 节的 位置 与 临床 参数 ,如 受压 神 经根 的水 平 ,直腿 抬高 试 验的 度数 ,术 前和 术 后症 状(腿痛 ,下 腰痛 和 行走 能力 )及 体 征(感 觉 和运 动障 碍 )的 严重 程 度 及 与恢复率 之间 的 关系 。结 果:与椎 管 内和 椎间 孔 内组 相比 ,椎 间孔 外 组患 者直 腿 抬高 试验 的 度数 较低 ,下 腰 痛的 程度较轻 ,术 前的 腿痛 明 显重 ,而 行走 能 力低 于椎 管 内和 椎间 孔 组。 背根 神 经节 的位 置 与术 前的 感 觉和 运 动 障 碍以及手 术效 果 没有 明显 差 异。结论 :神 经节 的 位置 会影 响 极外 型腰 椎 间盘 突出 患 者根 性症 状 (腿痛 和 行走 能力 )的严重 程度 。  相似文献   
62.
Summary Forty-four Parkinson patients (19 patients of the rigid-akinetic type, 13, of the rigid-akinetic-tremor type, and 12, of the tremor type) were included in a study in order to analyse correlations of the expression of the motor symptoms tremor, rigidity, akinesia, with other clinical parameters, computertomographic aspect of brain atrophy and psychometrically assessed cognitive parameters. Rigidity and akinesia are significantly positively correlated with the severity of motor dysability, stage of the disease, and brain atrophy, as is akinesia with a history of pharmacotoxic psychosis. Tremor is significantly negatively correlated with motor dysability, stage of the disease, and history of pharmacotoxic psychosis. Akinesia is correlated with visuomotor dysfunction (tested with Bender Gestalt Test) and rigidity with the depression score (Zung scale). The tremor type is favorable, the rigid-akinetic type unfavorable with respect to motor disability and psychosis.  相似文献   
63.
牙根发育不良疾病的研究进展   总被引:2,自引:0,他引:2  
牙根发育不良疾病是牙齿根部生理性发育出现障碍的疾病。其发病率为1%~10%,乳、恒牙列均可发生,其结果可导致牙根缺如或短根,严重者可造成牙齿过早脱落。国外学者将该疾病统称为短根异常疾病。其发病因素有遗传性疾病、全身性疾病、外源性因素和医源性因素等。  相似文献   
64.
Abstract – A histometric method was applied for evaluation of root resorption in 57 experimentally replanted teeth and 22 controls. Representative axiobuccolingual sections were selected for measurement of resorptions at a magnification of × 40. The frequency of root resorption in the control teeth was low. In replanted teeth marked resorptive activity elicited by the trauma appeared after 2 wk. The extent of active resorptions increased until the third postoperative week. On an average 14% of the root periphery was affected at this stage. After the sixth postoperative week progressive cement deposition took place in the resorption lacunae. Incidental ankylosis of the periodontal membrane also occurred from this observation time but there was no increase among the long-term groups.  相似文献   
65.
66.
Purpose Studies on musculoskeletal manifestations (MSM) of childhood acute lymphoblastic leukemia (ALL) have yielded variable findings with regard to their clinical impact. We investigated the significance for differential diagnosis, treatment and outcome of musculoskeletal complaints as presenting symptoms of ALL, and their correlation with leukemia immunophenotypes, for which data is lacking. Methods Data on 783 children in the national study for childhood ALL between 1984 and 2003 were reviewed retrospectively. Statistical analysis examined possible relationships between MSM at the time of diagnosis and demographic and clinical data, biological features of leukemia (peripheral blood counts, immunophenotype and main cytogenetic aberration), response to initial prednisone treatment, and outcome. Results Of 765 children with data on orthopaedic complaints, 240 presented with MSM (31.4%). Among these children, B cell precursor (BCP) was much more common (209/576, 36.3%) than T cell ALL (25/176, 14.2%). Patients with MSM had lower white blood cell counts (WBC) (median of 9 vs. 20 × 109/L, P < 0.001) and percentage of blast cells in the peripheral blood at diagnosis compared to those without (median of 27 vs. 53%, P < 0.001). Hepatomegaly and splenomegaly were less common in MSM group (67 vs. 53% <3 cm, P < 0.001, and 63 vs. 50% <3 cm, P < 0.001, respectively). Poor response to initial treatment with prednisone was recorded in 7.1% of patients with MSM versus 11.5% of those without (P = 0.086). The analysis revealed no independent effect of MSM on event-free survival (EFS), after correcting for differences in EFS related to immunophenotype or initial WBC. Conclusions MSM occur mostly in children with BCP ALL who present with less involvement of extramedullary organs, low peripheral blood blasts and white blood cells counts. These findings highlight the importance of including ALL in the differential diagnosis of MSM even in the presence of an apparently normal peripheral blood count. Our study also suggests that MSM are caused by leukemic cells with enhanced biological propensity to remain relatively confined within the intramedullary bone-marrow space.  相似文献   
67.
目的探讨乳腺癌新辅助化疗后动态增强MRI(DCE—MRI)表现的形态学和时间信号强度曲线(TIC)类型与病理学反应性的关系。方法45例乳腺癌患者经新辅助化疗结束后行乳腺DCE—MR检查及手术治疗。应用AW4.2图像工作站观察残余肿瘤强化的形态和TIC类型(共3型)。由病理科医师对乳腺癌化疗后手术标本的病理反应性进行评估,分为1~5级,5级为病理完全缓解,4级和5级为组织学显著反应。分析病理反应性级别与DCE—MRI残余强化的TIC类型、形态的关系,统计方法采用精确概率法。结果45例中病理反应性5级7例,4级16例,3级16例,1和2级共6例。20例I型曲线中组织学显著反应者占70.0%(14/20),而6例Ⅲ型曲线均为组织学反应不显著者。TIC类型在不同的病理反应级别分布差异有统计学意义(P=0.001)。组织学显著反应且有残余强化者共18例,其中非肿块性强化11例。残余强化的肿块(非肿块)形态表现在不同病理反应性分级中分布差异有统计学意义(P=0.012)。结论乳腺癌新辅助化疗后DCE—MRI的形态及血液动力学表现特点与化疗后病理反应性相关。非肿块性强化和I型TIC与组织学显著反应有关。  相似文献   
68.
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   
69.
本文综述了暴露前牙龈下残根进行桩冠修复的两种方法,即牵引法与牙冠延长术,并对两者进行了比较、总结,在临床上有指导意义。  相似文献   
70.
Restless legs syndrome (RLS) is a neurological disorder characterized by a compelling urge to move, accompanied by disturbing sensations within the legs. It is now recognized that RLS is a common condition that has a substantial impact on sleep, daily activities and quality of life. Recent data from the REST (RLS Epidemiology, Symptoms, and Treatment) general population study show that symptoms of RLS are present in approximately 7% of the general population, and that 2–3% experience moderate or severe symptoms at least twice a week. Amongst this RLS cohort, approximately 88% reported sensory disturbances and 76% reported sleep-related symptoms. These symptoms had a marked effect on everyday life, with up to 50% of the RLS cohort reporting disruption of everyday activities or personal relationships. Sleep disturbances in turn lead to impaired daytime functioning. RLS is associated with a significant impairment of quality of life, comparable with that seen in chronic medical conditions such as diabetes or depression. Given the significant burden of morbidity associated with RLS, there is a strong case for treatment in patients with troublesome symptoms.  相似文献   
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