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While movement disorders are frequently encountered after brain injuries, and may create a host of complicated problems for the clinician, only a few cases of Parkinsonism associated with hydrocephalus have ever been described in the literature. Parkinsonism-like syndrome complicating hydrocephalus is a rare disorder, especially when associated with nontumoral aqueductal stenosis. Yet as this case report discusses, hdyrocephalus-induced Parkinsonism may be responsive to levodopa-carbidopa administration. This report describes a perplexing case of persistent akinesis following corrective surgery for aqueductal stenosis and the subsequent response to levodopa-carbidopa administration. We present the case of a 28-year-old male with a history of non-tumoral aqueductal stenosis diagnosed at age 12. As a child, he underwent a ventriculo-peritoneal shunt placement for obstructive hydrocephalus followed by multiple shunt revisions over the next several years. Sixteen years after his initial shunt placement, the patient presented with a decline in mental status. A third ventriculocisternostomy was performed rather than another shunt revision. Following surgery, the patient remained obtunded, and displayed profound hypokinesis, best described as freezing in movement. Upon admission to a rehabilitation unit 2 weeks later, he had made only minimal progress. A SPECT (single-photon emission computed tomography) brain scan revealed decreased basal ganglia perfusion. Levodopa/carbidopa therapy was initiated and within 2 weeks, the patient showed improvement in speed of movement, facial expression and verbal output. Eight weeks later, the patient could independently complete his basic activities of daily living and demonstrated little, if any, disordered movement. This report illustrates how dopaminergic agents may be useful in cases of hypokinesis following corrective surgery for aqueductal stenosis. SPECT may further aid in the diagnosis and management of Parkinsonism-like syndromes in brain injuries.  相似文献   

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The authors present a case of secondary amenorrhea in a 32-year-old woman found to have noncommunicating hydrocephalus due to aqueductal stenosis. Although the presentation of hydrocephalus with amenorrhea has been previously reported, this association remains rare. After treatment via endoscopic third ventriculocisternostomy, the patient resumed normal menstruation and all hormonal abnormalities have resolved except hypothyroidism. A review of the literature on the etiology of endocrinological disturbances in patients with hydrocephalus is presented.  相似文献   

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The buoyancy of a single crystal copper cube in a lead tin melt was examined. A neutral buoyancy melt density of 8828 Kg/m3 at 250 °C was obtained which corresponds to a copper density of 8930 Kg/m3 at 20 °C. The copper cube was found to change from a floating to sinking position with changes in melt density of 1 Kg/m3. Contact with the crucible walls or meniscus prevented the copper cube from moving under buoyancy forces resulting from density differences as high 12 Kg/m3. This is attributed to surface tension forces at the points of contact of the copper, melt, crucible wall, and meniscus. Very small density variations in the copper due to micro-porosity and other imperfections was found to have a very large effect on the movement of the copper under buoyancy forces. In experiments in which grains of tin in partially solidified pure tin were allowed to settle under controlled conditions, it was found that many grains appeared to be separated from neighboring grains. In addition, regions clear of grains were observed in the settling region. It is suggested that this results from clumping of the grains and bridging of the clumps as they settle in the melt.  相似文献   

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The purpose of this study was to predict the uplift force during floods on confining layers that overlay extensive horizontal confined aquifers that intersect a large river in response to the water level changes that occur with time in a flooding river. Transient flow of water through the confined aquifer was described by a diffusion type of equation with a boundary condition at the river in which the river head varied with time. The transient head distribution developed from the unsteady flow model applied to the aquifer was compared with the hydraulic head distributions obtained from U.S. Army Corps of Engineers steady-state flow model and a finite-element seepage model. This study concluded that the transient flow model has the potential to analyze time lag in head development, and to predict the seepage condition and heaving potential at various times and distances landside of a levee during a flood cycle, but additional case histories are needed to justify widespread use of the model.  相似文献   

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BACKGROUND: Some months ago we described morphological changes in the stroma of the cornea of patients with a history of long term contact lens wear. These degenerations consist of little highly reflective structures called "micro-dots". For a more precise quantification of the micro-dots we established a clinically practicable method for measuring and counting. MATERIAL AND METHODS: The micro-dots can be visualized in optical sections with the scanning slit confocal microscope. To get the real thickness of a single optical section we had to develop a in vitro model, which consists of a gel of agar with particles of latex of different size. RESULTS: Some stereological methods made it possible to calculate the thickness of an optical section as seen with the confocal microscope. We found out that the thickness shows a variation depending on the reflectivity and size of the particles as well as on the aperture of the objective used. From the area of the frame and the thickness of the optical section we could calculate the density of the highly reflective particles. DISCUSSION: Up to now we could determine the morphological changes (micro-dots) in the cornea of patients with a history of long term contact lens wear in a semiquantitative manner only. With the presented method we are able to make a quite precise numerical estimation of micro-dots. This is very useful to follow up the progress of these stromal changes over many years.  相似文献   

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alpha-Melanocyte stimulating hormone (alpha-MSH) regulates skin and hair pigmentation by modulating the activity of MSH receptor (MC1R). We have identified Arg151Cys variant of human MC1R in genomic DNA isolated from a person with red hair and light skin of type I. The Arg151Cys variant of MC1R binds to radio-labelled analogue of alpha-MSH with identical affinity as wild type MC1R but can not be stimulated to produce cyclic AMP (cAMP). The mutation Arg151Cys renders human MC1R completely nonfunctional, which explains the red hair, light skin and poor tanning ability (skin type I). This is the first report ever describing a nonfunctional MC1R isolated from a human subject.  相似文献   

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针对连铸结晶器内弥散氩气泡的瞬态运动和捕捉行为,发展了耦合流动-传热凝固-气泡运动的大涡模拟模型,研究了结晶器凝固坯壳内钢液的非稳态湍流场和氩气泡的瞬态运动特征.结果表明,凝固坯壳对结晶器内钢液流场有较大影响,液相区内钢液流动不对称,导致气泡的运动和捕捉位置分布不均匀;小尺寸的气泡更容易运动到液相穴较深的区域;且随着拉...  相似文献   

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Diagnosis and treatment of patients with bleeding due to enhanced fibrinolysis is hampered by the absence of a rapid screen of fibrinolytic potential. The authors have developed a simple assay to assess clot structure and fibrinolysis in patient samples exposed to tissue plasminogen activator (TPA). They present the case of a forty-one-year-old man who presented with spontaneous bleeding despite normal results from coagulation screening tests, platelet count, platelet aggregation studies, platelet force development, and bleeding time. Evaluation of the patient's clot structure revealed a very weak, low-modulus, clot that rapidly dissolved in the presence of TPA. Identification of the abnormality allowed treatment with epsilon-aminocaproic acid with prompt resolution of bleeding.  相似文献   

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为了进一步认识水平分层综放开采的开采沉陷特点,运用相似材料模型实验,对某矿大倾角煤层的开采沉陷过程进行了模拟研究,揭示了急倾斜特厚煤层水平分层深部开采岩层与地表移动规律.  相似文献   

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A number of different procedures have been developed for use with matrix-assisted laser desorption/ionization mass spectrometry (MALDI/MS) for the analysis of non-covalent protein-protein complexes. These include use of specific matrix and laser combinations, accumulation of "first shot" spectra, modification of pH and solvent conditions during sample preparation and use of cross-linking agents to attach the monomers covalently to each other in the complex. The results have shown the techniques to be effective with some but not all complexes, although cross-linking is the most successful. The physical and chemical nature of the complex is critical and therefore a diversity of approaches is recommended for such studies.  相似文献   

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A molecular analysis of the arylsulphatase A gene was performed on 26 unrelated, Italian, late infantile metachromatic leucodystrophy patients. The frequency of the common disease causing mutations 609A and 2381T was 28.8% and 1.9% respectively. Pseudodeficiency allele frequency in patients was found to be 13.5% and a frequency of 10.1% was found in 89 unaffected normal controls. The frequency of the 609A mutation in Italian late infantile patients is lower than in late infantile patients from northern Europe, suggesting a higher frequency of different sporadic mutations in the Italian population. A cooperative in cis effect in phenotype determination involving arylsulphatase A mutations and the eventual background of the pseudodeficiency allele is proposed.  相似文献   

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