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排序方式: 共有490条查询结果,搜索用时 31 毫秒
1.
本文对29例脑标本行 MRI-病理对照研究,其中18例脑标本 MRI 检查阳性,发现脑皮质下斑点状病灶(Subcortical Patchy Lesions,SPLs)95个。该病灶分两大类:第一类(64个)位于脑皮层下白质、基底核、小脑和脑干,其病理基础主要为血管周围间隙扩大(83%),小梗塞灶(11%),其他还有小动、静脉畸形(AVM),脱髓鞘灶和胶质增生灶;第二类(31个)位于侧脑室周围白质内,其病理基础为局部组织结构疏松呈空泡状,病灶相应部位的室管膜大片脱落。  相似文献   
2.
BackgroundKnee osteoarthritis (KOA) is increasingly prevalent in North American society. The significant societal burden it represents makes it essential to promote and target new treatments in earlier phases of the disease. Among others, subchondroplasty is a newly documented technique using calcium phosphate injection targeting the osteochondral lesions preceding KOA, also known as Bone Marrow Lesions (BMLs). This article aimed to review the existing literature on clinical and radiological outcomes of subchondroplasty in the treatment of BMLs in KOA.MethodA systematic review was performed using PubMed, Embase, Medline and Cochrane Database of Systematic Reviews. Studies on calcium phosphate injections into BMLs for KOA and its clinical and radiological outcomes were screened and reviewed by independent evaluators.ResultsAfter screening, ten articles were included, totaling 540 patients. Follow-up ranged from 6 months to 7 years. Overall, the procedure showed significant functional and quality of life improvement, as well as pain relief, as shown by Patients-Reported Outcomes Measures (PROMs). There were very few complications reported, the most important being leakage of calcium phosphate outside the targeted site. Conversion rate to total knee arthroplasty (TKA) ranged from 14 % to 30 % at 2 years post-procedure. Long term radiological outcomes have been poorly documented.ConclusionsSubchondroplasty is a promising avenue for the treatment of KOA. However, quality evidence is still required before any real conclusions and practical management guidelines can be drawn. Prospective, randomized studies with a control group and a rigorous assessment of long-term clinical and radiological outcomes are recommended.  相似文献   
3.
Summary The descending pathways responsible for eliciting forelimb stepping are located in the lateral funiculus (Yamaguchi 1986). In order to determine into which spinal segments the descending pathways project and to know the projections and functions of the other descending system, the ventral funicular pathways, we placed various lesions in the cervical spinal cord of decerebrate cats with the lower thoracic cord transected and studied their effects on forelimb stepping evoked by stimulation of the midbrain locomotor region. (1) The lateral funiculus was transected on one side. The operation removes descending input to all the segments caudal to the lesion. Experiments with serial transections from the caudal to rostral segment revealed that stepping activity of the limb on the lesioned side is reduced when the lesion is placed at the level between the C6 and C7 segment and then between C5 and C6. A slight reduction of activity was also observed after a lesion placed between C7 and C8. (2) Consistently, bilateral transection of the lateral funiculus at the level between C5 and C6 abolished stepping movements of both forelimbs. (3) The cervical cord was split in the parasagittal plane through the dorsal root entry. The operation removes the descending input to the segment in which the lesion is placed. The parasagittal lesions from the C1 to C6 did not abolish stepping activity, although a lesion placed between C5 and C6 could slightly affect stepping. The results, (1)–(3) suggest that the lateral funicular pathways project into the spinal segments mainly at the C6–C7 level with some rostrocaudal extension into C5 and C8. (4) Complete transections of the medial part of the spinal cord cut extensor bursts short and raised stepping frequency. Nevertheless, if the lesion at C1–C5 spared the ventromedial part of the ventral funiculus, it did not result in such high-frequency stepping or in weakened extensor activity. In the case of segments caudal to C6, medial transections which spared the corresponding region could result in such stepping. It is suggested that the pathways descending through the ventromedial part of the ventral funiculus in the rostral segments provide extensor activity during stepping. They may change their course in the more dorsal part of the ventral funiculus below the C6 and presumably project into the grey matter of more caudal segments.  相似文献   
4.
Central amygdaloid nucleus lesions in rats had no effect on recovery of preoperative body weight and food consumption levels. The brain damaged rats also recovered preoperative levels of water consumption as rapidly as control rats but then developed a mild but persistent hypodipsia. The experimental rats also drank less than control rats when food deprived and showed marginally reliable decreases in 0.1% quinine solution consumption and latency to consume a novel food. There was no detectable lesion effect on 0.1% saccharin solution consumption, exploration of a novel environment or formation of a learned taste aversion. It is suggested that the central amygdaloid nucleus has a role in mediating the relationship between food and water intake and in some taste mediated consummatory behavior.  相似文献   
5.
Summary The purpose of this study was to investigate whether bilateral lesions to a part of the hyperstriatum ventrale (IMHV) impair retention if they are placed after chicks have been imprinted. Domestic chicks were hatched and reared in darkness and exposed to an imprinting (training) stimulus for 2 h commencing 22 h post hatch. The chicks were then anaesthetised and bilateral lesions placed in IMHV (N = 16) birds, hyperstriatum accessorium (HA; N = 16) or the lateral part of the cerebral hemispheres (LCA; N = 16). Forty-eight sham-operated chicks served as controls. Chicks were returned to the dark incubator, and, 15–20 h after the operation, their approach towards the training stimulus and to a second novel stimulus was measured. The controls and the chicks with lesions in HA and LCA showed a strong preference for the training stimulus and hence a high level of retention. The preferences of these three experimental groups did not differ significantly from one another. The mean preference of chicks with lesions in IMHV was significantly less than that of the sham-operated controls (P<0.01) and of chicks lesioned in HA (P<0.05). Bilateral lesions to IMHV therefore selectively impair retention of a preference acquired through imprinting. This impairment is unlikely to be a non-specific consequence of defective sensory processing or motor performance because the four groups did not differ from each other in (i) the time taken accurately to peck a rocking bead, (ii) the accuracy of pecking millet seeds and (iii) the performance of a simultaneous visual discrimination task involving heat reinforcement.Supported by grants from the Science Research Council, the Leverhulme Trust, the Wellcome Trust and FAPESP (Brazil)  相似文献   
6.
血清胆红素与冠脉病变程度及血脂的相关性分析   总被引:15,自引:4,他引:11  
目的分析血清胆红素与冠脉病变程度及血脂的关系。方法对冠状动脉造影术确诊的冠心病者和非冠心病者进行病例-对照研究。结果冠心病组血清胆红素水平低于非冠心病组,差异有显著性(P<0.05)。多元逐步回归分析血清直接胆红素进入回归方程,提示血清直接胆红素与冠脉病变程度呈独立负相关,其相关强度与甘油三脂(TG)和空腹血糖(FBS)相似。血清胆红素与血脂直线相关分析提示血清胆红素与甘油三脂、总胆固醇(TCHO)和低密度脂蛋白胆固醇(LDL-C)呈显著负相关。结论血清直接胆红素水平与冠脉病变程度呈独立负相关,低血清胆红素是冠状动脉粥样硬化的危险因素,血清胆红素与甘油三脂、总胆固醇和低密度脂蛋白胆固醇呈负相关。  相似文献   
7.
目的:探讨眼球运动障碍、眼球震颤对脑干病变定位的临床意义。方法:对39例经CT、MRI证实为脑干病变的患者行眼球运动障碍、眼球震颤分析。结果:眼球垂直注视麻痹、会聚麻痹对中脑病变有定位意义;核间性眼肌麻痹对中脑、脑桥病变有定位意义;眼球水平运动障碍对脑桥病变有定位意义;延髓病变无眼球运动障碍;眼球震颤可发生在脑干各种部位病变。结论:眼球运动障碍对脑干病变定位有临床意义;眼球震颤尤其是垂直性、旋转性  相似文献   
8.
Summary The effect of lesioning the ipsilateral globus pallidus (GP) on apomorphine-induced circling in nigrostriatal lesioned rats was investigated. A GP electrolesion almost abolished circling. Drugs that affect GABA and opiate receptors were injected in GP through a cannula. Circling was antagonized by the GABA antagonists picrotoxin and bicuculline, the GABA agonist muscimol and by baclofen. Opiate receptor agonists including morohine, levorphanol, [d-Ala2, d-Leu5]-enkephalin and -endorphin had no effect on circling in GP. Ethylketazocine caused a pronounced, naloxone-reversible slowing of apomorphine circling. Apomorphine-induced circling behaviour may be modulated by GP GABA receptors and kappa-type opiate receptors.  相似文献   
9.
The effects of dorsal noradrenergic bundle (DNB) lesions on plasma corticosterone levels were determined in male albino rats. DNB lesions did not affect baseline plasma corticosterone levels. Furthermore, the increased corticosterone levels produced by various environmental manipulations did not differ between control and DNB lesioned groups. However, the lesioned group did exhibit longer latencies to eat familiar food in novel environments, as well as to eat novel foods in a familiar environment. Latencies to eat novel food in novel environments did not differ between the two groups and this was attributed to a "ceiling" effect. These endocrinological data fail to support the hypothesis that the enhanced "neophobia" observed in DNB lesioned rats is due to an increase in the intensity of the emotional reaction to novel stimuli. The data do not preclude the possibility, however, that the enhanced neophobic reactions reflect impaired habituation to these stimuli.  相似文献   
10.
A high salt diet produced increases in SBP, urinary protein excretion (UPE) and renal vascular lesions (RVL) across groups of male and female SHR rats which were allowed to develop moderate or excessive increases in SBP. A highly significant linear relationship between SBP and log-transformed UPE was found when the data from all groups were analyzed together. Males developed high blood-pressure more rapidly, and exhibited more severe RVL and greater UPE than females. Two results prevent the conclusion that the elevated UPE was simply due to the adverse effects of high BP on the kidney. First, the relationship between SBP and UPE across groups could not be demonstrated when regression analyses were performed within individual dietary sub-groups. Secondly, gender differences in UPE were highly significant by analysis of covariance adjusting for individual differences in SBP. The increases in SBP and UPE may be independent consequences of ingestion of a high salt diet.  相似文献   
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