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排序方式: 共有4333条查询结果,搜索用时 15 毫秒
41.
目的:探讨颈内动脉岩内段形态位置变化的规律及其与毗邻结构的关系.方法:对66侧正常成人颅底高分辨率CT连续图像进行分析,测量颞骨气房体积,建立定位颈内动脉岩内段及其毗邻结构的参照系,对其位置和形态进行测量,运用偏相关分析方法求出它们形态位置的变化规律及其影响因素.结果:在男性,颈内动脉垂直段更偏外侧,其水平段长度也大于女性.颞骨气化好,则颈内动脉垂直段更偏后移.颈内动脉垂直段与颈静脉球的位置变化表现为同步.垂直段的内外移位相应地使水平段与中线的夹角发生变化.颈内动脉水平段的方位与蜗轴方向相关,蜗轴偏离中线的角度越小,则颈内动脉水平段偏离中线的角度越大,反之亦然.结论:影响颈内动脉岩内段形态位置变化的因素是复杂和多重的,包括性别因素、颅底发育状态、颞骨气化程度以及毗邻结构发育状态均可能是影响因素. 相似文献
42.
U. Sławin´ska F. Tyc˘ S. Kasicki R. Navarrete G. Vrbová 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(2):193-201
After partial denervation, the remaining motor units (MUs) of adult fast extensor digitorum longus muscle (EDL) expand their
peripheral field. The time course of this event was studied using tension measurement and recordings of electromyographic
(EMG) activity. The results show that after section of the L4 spinal nerve, when only 5.3 ± 0.63 of the 40 MUs normally supplying
EDL muscle remain, the force of individual motor units starts to increase between the 1st and 2nd week after the operation
and continues to do so for a further week. The drastic reduction of the number of motoneurones supplying the fast EDL leads
to an increase in activity of the remaining MUs. In the 1st week after partial denervation, there was a sharp increase in
the EMG activity of remaining motor units. During the next 12 days, this increase became less marked, but EMG activity remained
nevertheless significantly higher than that of the unoperated EDL muscle. Many MUs became tonically active during posture.
The EMG activity pattern during locomotion was also altered, so that the burst duration was positively correlated with the
step cycle duration. Moreover, shortly after partial denervation, the interlimb coordination was disturbed but returned to
its original symmetrical use 1–2 weeks later.
Received: 17 September 1996 / Accepted: 3 November 1997 相似文献
43.
局限性癫痫脑电时间序列的分形维数计算比较 总被引:1,自引:0,他引:1
为探索应用非线性动力学理论诊断癫痫病的新方法,对局限性癫痫病患者脑电时间序列进行了相关维数(Dc)和波形维数(Dw)的计算比较。观察到,痫性导联脑电的分形维数多低于对侧导联的值;相关维数Dc的相对变化量较波形维数Dw大;而波形维数Dw对痫性棘波敏感;结果提示,脑电时间序列的分形维数有可能成为诊断癫痫的特征参数,值得进一步深入研究。 相似文献
44.
In an n-back face recognition task where subjects responded to repeated stimuli, ERPs were recorded to upright, inverted, and contrast-reversed faces. The effects of inversion and contrast reversal on face encoding and recognition were investigated using the multivariate spatiotemporal partial least squares (PLS) analysis. The configural manipulations affected early processing (100-200 ms) at posterior sites: Inversion effects were parietal and lateral, whereas contrast-reversal effects were more occipital and medial, suggesting different underlying generators. A later reactivation of face processing areas was unique to inverted faces, likely due to processing difficulties. PLS also indicated that the "old-new" repetition effect was maximal for upright faces and likely involved frontotemporal areas. Marked processing differences between inverted and contrast-reversed faces were seen, but these effects were similar at encoding and recognition. 相似文献
45.
Morphologic evaluation of the liver in hereditary angioedema patients on long-term treatment with androgen derivatives 总被引:1,自引:0,他引:1
M Cicardi L Bergamaschini A Tucci A Agostoni G Tornaghi G Coggi R Colombi G Viale 《The Journal of allergy and clinical immunology》1983,72(3):294-298
17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses. 相似文献
46.
Partial epilepsy in neurologically normal children: clinical syndromes and prognosis 总被引:11,自引:8,他引:3
A clinical and electroencephalographic study of 107 neurologically normal children with partial seizures was undertaken to verify the existence and determine the frequency of epileptic syndromes reported in selected populations. Sixty-three children had simple partial seizures, 39 had complex partial seizures, and 5 children were unclassifiable. The syndrome of benign partial epilepsy of children with rolandic spikes (BPEC, 38 cases) was clearly identified and its uniformly benign final prognosis was confirmed even if some of these children had at times severe or poorly controlled seizures. Among the children with simple partial seizures outside the BPEC (25 cases) and complex partial seizures (39 cases), no homogeneous clinical or electroclinical subgroup could be found. Two children with benign partial epilepsy and myoclonic-astatic seizures ("atypical benign partial epilepsy of childhood") and one child with "benign epilepsy with occipital spike-waves" were identified. 74% of children with epilepsy with complex partial seizures (ECP) had a 1-year seizure-free interval, and many children with epilepsy with simple partial seizures outside the BPEC group (ESP) had no more than two seizures. A benign course is thus not limited to the BPEC but is difficult to predict. Prospective studies are necessary to confirm the existence of well-defined benign syndromes among the idiopathic partial epilepsies of childhood, which appear quite rare outside the BPEC. 相似文献
47.
The effects of amphetamine on the partial punishment effect (PPE) at one trial per day, were examined. Two groups of animals were trained to run in a straight alley. The continuously reinforced (CRF) group received food reward on every trial. The partially punished (PP) group received food reward on every trial but in addition, received footshocks of a gradually increasing intensity in the goal box on a random 50% of the trials. In the test stage, all animals received both food and footshock on each trial. dl-Amphetamine 1.5 mg/kg was administered in a 2 × 2 design, i.e. drug-no drug in training and drug-no drug in test. The partially punished animals exhibited increased persitence in running to the goal box during test, and this partial punishment effect was unaffected by amphetamine. 相似文献
48.
目的:探讨喉部分切除术的疗效及修复方法。方法:回顾分析1980年1999年施行喉部分切除术81例的临床资料,其中声门上型喉癌22例、声门型喉癌59例。结果:声门上型喉癌3、5年生存率分别为66.7%、63.2%,声门型喉癌3、5年生存率分别为87.2%、80.5%。拔管率声门上型喉癌为77.2%(17/22),声门型喉癌为93.2%(55/59)。结论:喉部分切除术能保留大部分患者喉的呼吸及发声功能,是根治喉癌的有效术式。 相似文献
49.
Sameer Haveri Kiran S. Patil Rajendra B. Uppin Santosh Patil B. B. Putti 《Indian Journal of Orthopaedics》2021,55(2):457
Background and AimSeveral patient-related factors have been identified which are responsible for the development of rotator cuff tears. The purpose of the study was to assess various parameters which can be risk factors for the development of supraspinatus tendon tear.MethodsA total of 100 patients with symptomatic rotator cuff tear, aged > 18 years, of either gender, presenting to the outpatient department were included in this cross-sectional study. Magnetic resonance imaging was done and based on its results; patients were identified for the type of tear. Demographic, clinical, and biochemical factors affecting the tears were assessed using logistic regression analysis.ResultsFactors such as age, gender, pain radiation, night pain, and analgesic intake had significant association with supraspinatus tendon tears.Conclusion“Pain radiation” and “Analgesic intake” were two new parameters found associated with the supraspinatus tendon tears. New parameters that have been assessed as risk factors will help in better understanding of supraspinatus tendon tears. 相似文献
50.
Introduction:Minimally invasive partial nephrectomy is standard of care treatment for small renal masses.Objective:We evaluated the relationship between subcutaneous and visceral obesity with high-grade postoperative 30-day complications in patients undergoing minimally invasive partial nephrectomy.Methods:We retrospectively identified 98 patients at our institution from 2014 to 2017 who underwent laparoscopic or robotic-assisted partial nephrectomy due to suspected renal cell carcinoma. Patients were stratified based on presence or absence of high-grade (Clavien ≥ IIIa) 30-day postoperative complications. Means were compared with the independent t test and proportions with chi-square analysis. Multivariate logistic regression was performed to determine independent predictors of high-grade 30-day complications.Results:Mean nephrometry score was 6.7 with 21 (21.4%) patients having hilar tumors. Mean estimation of blood loss was 207 mL, mean operating time was 223 min, and mean warm ischemia time was 23 min. The majority of patients had clear renal cell carcinoma (n = 83, 84.7%) and pT1a disease (n = 76, 77.6%) with negative margins (n = 89, 90.8%) on pathology. There were 5 (5.1%) patients who experienced a high-grade postoperative 30-day complication. Mean visceral fat index was an independent predictor of high-grade 30-day complications (odds ratio: 1.02; 95% confidence interval: 1.002–1.03; p = 0.027).Conclusions:Visceral obesity should be considered as a prognostic indicator of outcomes in patients undergoing surgical treatment for a small renal mass. 相似文献