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81.
A 67-year-old gentleman presented to Yale-New Haven Hospital (YNHH) for assessment of a supratherapeutic INR and sacral lesion. Hematologic workup revealed elevated ESR, PT, INR, PTT, and CRP, mixing studies that failed to correct, and a positive Russell Viper Venom Test (RVVT), which confirmed the presence of lupus anticoagulant (LA), a subtype of antiphospholipid syndrome (APA). Pathology of the patient's sacral lesion revealed diffuse large B-cell lymphoma. This case provides insight into the association between APA and lymphoid neoplasm. The patient's unique presentation is in marked contrast to other reports of APA and lymphoid malignancy, which are typically associated with elevated PTT, normal PT, minimal extranodal disease, and potential thrombotic complications. Further, treatment with Rituximab-CHOP chemotherapy led to excellent clinical response with tumor remission and normalization of PT and PTT. 相似文献
82.
Sonja A. Kotz Anika Stockert Michael Schwartze 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1658)
We live in a dynamic and changing environment, which necessitates that we adapt to and efficiently respond to changes of stimulus form (‘what’) and stimulus occurrence (‘when’). Consequently, behaviour is optimal when we can anticipate both the ‘what’ and ‘when’ dimensions of a stimulus. For example, to perceive a temporally expected stimulus, a listener needs to establish a fairly precise internal representation of its external temporal structure, a function ascribed to classical sensorimotor areas such as the cerebellum. Here we investigated how patients with cerebellar lesions and healthy matched controls exploit temporal regularity during auditory deviance processing. We expected modulations of the N2b and P3b components of the event-related potential in response to deviant tones, and also a stronger P3b response when deviant tones are embedded in temporally regular compared to irregular tone sequences. We further tested to what degree structural damage to the cerebellar temporal processing system affects the N2b and P3b responses associated with voluntary attention to change detection and the predictive adaptation of a mental model of the environment, respectively. Results revealed that healthy controls and cerebellar patients display an increased N2b response to deviant tones independent of temporal context. However, while healthy controls showed the expected enhanced P3b response to deviant tones in temporally regular sequences, the P3b response in cerebellar patients was significantly smaller in these sequences. The current data provide evidence that structural damage to the cerebellum affects the predictive adaptation to the temporal structure of events and the updating of a mental model of the environment under voluntary attention. 相似文献
83.
Claudia Kathe Thomas H. Hutson Qin Chen Harold D. Shine Stephen B. McMahon Lawrence D. F. Moon 《Journal of visualized experiments : JoVE》2014,(94)
The corticospinal tract (CST) can be completely severed unilaterally in the medullary pyramids of the rodent brainstem. The CST is a motor tract that has great importance for distal muscle control in humans and, to a lesser extent, in rodents. A unilateral cut of one pyramid results in loss of CST innervation of the spinal cord mainly on the contralateral side of the spinal cord leading to transient motor disability in the forelimbs and sustained loss of dexterity. Ipsilateral projections of the corticospinal tract are minor. We have refined our surgical method to increase the chances of lesion completeness. We describe postsurgical care. Deficits on the Montoya staircase pellet reaching test and the horizontal ladder test shown here are detected up to 8 weeks postinjury. Deficits on the cylinder rearing test are only detected transiently. Therefore, the cylinder test may only be suitable for detection of short term recovery. We show how, electrophysiologically and anatomically, one may assess lesions and plastic changes. We also describe how to analyse fibers from the uninjured CST sprouting across the midline into the deprived areas. It is challenging to obtain >90% complete lesions consistently due to the proximity to the basilar artery in the medulla oblongata and survival rates can be low. Alternative surgical approaches and behavioural testing are described in this protocol. The pyramidotomy model is a good tool for assessing neuroplasticity-inducing treatments, which increase sprouting of intact fibers after injury. 相似文献
84.
Transcranial magnetic stimulation (TMS) has proven to be a useful tool in investigating the role of the articulatory motor cortex in speech perception. Researchers have used single-pulse and repetitive TMS to stimulate the lip representation in the motor cortex. The excitability of the lip motor representation can be investigated by applying single TMS pulses over this cortical area and recording TMS-induced motor evoked potentials (MEPs) via electrodes attached to the lip muscles (electromyography; EMG). Larger MEPs reflect increased cortical excitability. Studies have shown that excitability increases during listening to speech as well as during viewing speech-related movements. TMS can be used also to disrupt the lip motor representation. A 15-min train of low-frequency sub-threshold repetitive stimulation has been shown to suppress motor excitability for a further 15-20 min. This TMS-induced disruption of the motor lip representation impairs subsequent performance in demanding speech perception tasks and modulates auditory-cortex responses to speech sounds. These findings are consistent with the suggestion that the motor cortex contributes to speech perception. This article describes how to localize the lip representation in the motor cortex and how to define the appropriate stimulation intensity for carrying out both single-pulse and repetitive TMS experiments. 相似文献
85.
Collagenous spherulosis is a rare incidental finding seen in association with benign breast lesions. Cytological findings in three cases of collagenous spherulosis diagnosed on fine needle aspiration are presented. The presence of hyaline pink globules surrounded by benign myoepithelial cells in Giemsa stained smears was a diagnostic feature. Associated lesions were atypical papillary hyperplasia (2) and fibroadenoma (1). Adenoid cystic carcinoma was the close differential diagnosis on cytology. Awareness of this entity is important to avoid a false positive diagnosis of malignancy. 相似文献
86.
Ulrich Zunke 《Journal of nematology》1990,22(3):309-320
The endoparasitic behavior of Pratylenchus penetrans was examined using video-enhanced contrast microscopy to observe living nematodes inside root tissue. Feeding behavior could be separated into phases of probing, cell penetration by the stytet, salivation, and food ingestion for brief and extended periods. After cell penetration, a small "salivation zone" was formed around the stylet tip. No feeding tubes were observed. Feeding and migration were interrupted by rest phases when a nematode became characteristically coiled inside a cell. Tissue damage was caused primarily by migration and extended feeding periods. Aspects of egg laying and molting are also described. 相似文献
87.
γ-Aminobutyric Acid and Benzodiazepine Receptor Changes Induced by Unilateral 6-Hydroxydopamine Lesions of the Medial Forebrain Bundle 总被引:5,自引:2,他引:3
Quantitative autoradiography was used to ascertain alterations in [3H]muscimol, [3H]flunitrazepam (FLU), [3H]naloxone, [3H]D-alanine-D-leucine-enkephalin (DADL), and [3H]spiroperidol binding in basal ganglia 1 week, 4 weeks, and 5 months after unilateral 6-hydroxydopamine lesions of the medial forebrain bundle (MFB) in the rat. At 1 and 4 weeks following lesions, [3H]spiroperidol binding increased 33% in striatum. At 5 months, [3H]spiroperidol was only nonsignificantly increased above control. At 1 week, [3H]muscimol binding decreased 39% in ipsilateral globus pallidus (GP), but increased 41% and 11% in entopeduncular nucleus (EPN) and substantia nigra pars reticulata (SNr), respectively. At 4 weeks, [3H]muscimol binding was reduced 19% in striatum and 44% in GP and remained enhanced by 32% in both EPN and SNr. These changes in [3H]muscimol binding persisted at 5 months. [3H]FLU binding was altered in the same direction as [3H]muscimol binding; however, changes were slower in onset and became significant (and remained so) only at 4 weeks after lesions. Decreases in [3H]naloxone and [3H]DADL binding were seen in striatum, GP, EPN, and SNr. Scatchard analyses revealed that only receptor numbers were altered. This study provides biochemical evidence for differential regulation of striatal GABAergic output to GP and EPN/SNr. 相似文献
88.
11例肿瘤致癫痫病患者在脑皮质电图和深部电极描记监测致癫痫灶下,行肿瘤和致痫灶的切除。用免疫组织化学方法检测肿瘤和致痫灶内的细胞浆内胶质原纤维酸性蛋白、神经细丝、纤维联结蛋白和内皮细胞及电镜观察。发现致痫灶分别在肿瘤灶(5例)和肿瘤的周边区(6例)内,每一致痫灶内见残留神经元或变性的轴索由瘤性或增生的星形细胞的胶质原纤维或增生血管周细胞的胶原原纤维围绕或包绕;致痫灶内神经元固缩或空泡变性,线粒体肿胀、粗面内浆网扩张,轴索变性及髓鞘板层分离。结合上述所见,讨论了星形细胞在癫痫发作中的机理。 相似文献
89.
目的:研究超声引导下Mammotome微创旋切术对乳腺良性肿块的治疗价值。方法:回顾性分析2014年9月至2016年9月在本院就诊的BI-RADS分级为2~3级的387例乳腺良性肿块患者,运用Mammotome对729处乳腺病灶行微创旋切术,分析术后病理、并发症、随访半年后的治疗结果。结果:387例患者的729处乳腺病灶均获一次性成功切除。病理示均为良性病灶,其中32个合并不典型增生。术后出现局部血肿共11例(2.8%),皮下瘀斑共16例(4.1%),所有患者均未发生感染及气胸等严重并发症。术后6个月18个在病灶原部位发现肿块;手术无残留率为97.5%。结论:应用超声引导下Mammotome微创旋切术治疗乳腺良性肿块临床可行。 相似文献
90.
目的:探讨生殖道感染与宫颈癌、宫颈癌前病变的相关性及危险因素分析。方法:选取我院收治的185例宫颈癌及宫颈癌前病变患者和同期206例健康体检者分为两组,对人乳头瘤病毒(HPV)、沙眼衣原体(CT)、细菌性阴道病(BV)、阴道滴虫进行检测,观察分析相应病原微生物导致的生殖道感染与宫颈癌及宫颈癌前病变的关系,同时根据HPV不同基因型在宫颈癌及宫颈癌前病变中的致癌作用和程度,判定危险程度。结果:宫颈癌及宫颈癌前病变患者上述指标感染检出率明显高于对照组,差异具有统计学意义(P=0.000、0.001、0.000、0.037),其中高危HPV感染率随宫颈上皮内瘤变级别的升高而呈明显上升趋势,CINⅠ~Ⅲ级感染率分别为57.1%、78.6%和82.9%,宫颈癌感染率最高达91.1%,高危HPV为高危因素。结论:生殖道HPV、CT、BV、滴虫感染与宫颈癌及CIN存在必然或一定相关性,加强对妇女生殖道病原体感染的重视和检测对防治宫颈癌及CIN具有积极意义。 相似文献