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81.
Seven cerebral gliomas in short-term culture were studied by microspectrofluorometry and acridine orange staining to assess their nuclear content of single- and double-stranded DNA. Benign gliomas showed a diploid DNA pattern, whereas malignant gliomas revealed a higher frequency of DNA aneuploidy and hyperploidy. The content of single-stranded DNA remained relatively low in benign gliomas; however, that in malignant gliomas varied widely. After ACNU treatment, the double-stranded DNA histograms showed S-phase-specific accumulation in all cases but 1 with increasing concentrations of ACNU. The single-stranded DNA content decreased considerably in 2 cases, which responded well to chemotherapy and showed clinical amelioration.  相似文献   
82.
Pre- and postoperative pneumoencephalo-roulette tomography has been carried out in two cases of primary pontine haemorrhage with long survival. A pontine or cerebellar atrophy was revealed in case 1, in whom an intrapontine haematoma was removed. A markedly hollowed pons on the affected side has been demonstrated nearly five months after ventriculoatrial shunting in case 2.  相似文献   
83.
Abstract: In order to understand the mechanisms underlying seizure generation, the present study investigated the functional and anatomical interaction between seizures and interictal bursts. Bathing rat brain slices of the hippocampus and entorhinal cortex in zero magnesium medium elicited electrographic seizures. In the later period, the electrographic seizures were eventually replaced by the interictal bursts. In this phase, lowering [K+]0 and raising [Ca2+]0, restored the tonic seizures by suppressing the interictal bursts. A multiple knife cut experiment revealed that the seizures arose in the entorhinal cortex and the interictal bursts originated in CA3. A selective knife cut across the subiculum showed that the interictal bursts, propagating from CA3 to the entorhinal cortex, disrupted and suppressed the electrographic seizures in standard Mg–free medium.  相似文献   
84.
Two cases of a saccular aneurysm of the posterior inferior cerebellar artery associated with an anatomically related arteriovenous malformation are presented. The aneurysms were clipped and the arteriovenous malformations were totally extirpated in one-stage operations in both cases. The association of arteriovenous malformation and arterial aneurysm in the posterior fossa was reviewed in the literature.  相似文献   
85.
In an effort to achieve efficient image management in clinical neurosurgery utilizing a local image filing system (EFPACS, Fuji Electric Co., Ltd), adequate image-processing and display techniques were developed. One is a method whereby the anatomical location of the thalamic and basal ganglion lesions is determined by automatically superimposing these lesions defined by magnetic resonance imaging (MRI) directly onto the Schaltenbrand-Wahren's human brain atlas. Horizontal, coronal and sagittal MR images are initially obtained based on the intercommissural line and a perpendicular erected on the midcommissural point as the basic reference coordinates. Precise superimposition is accomplished by the use of these reference axes. This imaging technique may offer the potential for help in anatomical identification of small intracranial lesions. Another technique described in the current communication is automated synthesis of two cerebral angiograms. By simply indicating two reference points, nasion and inion, with a cursor on the display screen, two films are automatically superimposed and displayed as a single synthesized image, featuring two different vascular phases simultaneously by a positive(vein)-negative(artery) mode. This technique was applied to patients with complete occlusion of the middle cerebral artery with or without sufficient blood flow through collateral circulation and was found useful in evaluating basic hemodynamics on a single angiographic image.  相似文献   
86.
There are many varieties of gastroenteritis viruses, of which norovirus (NoV) accounts for over 90% of the viral food poisoning incidents in Japan. However, protocols for rapidly identifying other gastroenteritis viruses need to be established to investigate NoV‐negative cases intensively. In this study, a multiplex real‐time PCR assay targeting rotavirus A, rotavirus C, sapovirus, astrovirus, adenovirus, and enterovirus was developed using stool samples collected from gastroenteritis patients between 2010 and 2013 in Fukui Prefecture, Japan. Of the 126 samples collected sporadically from pediatric patients with suspected infectious gastroenteritis, 51 were positive for non‐NoV target viruses, whereas 27 were positive for NoV, showing a high prevalence of non‐NoV viruses in pediatric patients. In contrast, testing in 382 samples of 58 gastroenteritis outbreaks showed that non‐NoV viruses were detected in 13 samples, with NoV in 267. Of the 267 NoV‐positive patients, only two were co‐infected with non‐NoV target viruses, suggesting that testing for non‐NoV gastroenteritis viruses in NoV‐positive samples was mostly unnecessary in outbreak investigations. Given these results, multiplex real‐time PCR testing for non‐NoV gastroenteritis viruses, conducted separately from NoV testing, may be helpful to deal with two types of epidemiological investigations, regular surveillance of infectious gastroenteritis and urgent testing when gastroenteritis outbreaks occur.  相似文献   
87.
88.

Background

Dysmyelination is hypothesized to be one of the causes of schizophrenic symptoms. Supporting this hypothesis, demyelination induced by cuprizone was recently shown to cause schizophrenia-like symptoms in adult rodents [Xiao L, Xu H, Zhang Y, Wei Z, He J, Jiang W, et al. Quetiapine facilitates oligodendrocyte development and prevents mice from myelin breakdown and behavioral changes. Mol Psychiatry 2008;13:697–708]. The present study asked if the timing of demyelination (i.e., juvenile period or adulthood) influenced abnormal behavior.

Methods

B57BL/6 mice were fed with 0.2% cuprizone either from postnatal day 29 (P29) to P56 (early demyelination group) or from P57 to P84 (late demyelination group), and then returned to normal mouse chow until P126, when the behavioral analysis was initiated.

Results

In both groups, the intake of cuprizone for 28 days produced massive demyelination in the corpus callosum by the end of the treatment period, and subsequent normal feeding restored myelination by P126. In a Y-maze test, the spatial working memory was impaired in both groups right after the cuprizone feeding ceased, consistent with previous studies, whereas only the early demyelination group exhibited impaired working memory after remyelination took place. In an open field test, social interactions were decreased in the early demyelination group, but not in the late group. Novel cognition and anxiety-related behaviors were comparable between the two groups.

Conclusions

Our findings suggest that the timing of demyelination has substantial impacts on behaviors of adult mice.  相似文献   
89.
Localization of ADAMTS13 to the stellate cells of human liver   总被引:12,自引:2,他引:12       下载免费PDF全文
Although the chromosomal localization (9q34) of the gene encoding the human form of ADAMTS13 (a disintegrin-like and metalloproteinase with thrombospondin type-1 motifs 13) and its exclusive expression in the liver have been established, the cells that produce this enzyme are yet to be determined. We investigated the expression of ADAMTS13 mRNA and protein in fresh frozen specimens obtained during liver biopsies of 8 patients with liver diseases. In situ hybridizations to localize ADAMTS13 mRNA showed positive signals exclusively in perisinusoidal cells with irregularly elongated dendritic processes extending between hepatocytes. Furthermore, ADAMTS13 was detected immunohistochemically in perisinusoidal cells, whereas no staining was observed in hepatocytes. The positive cells varied in shape from unipolar to dendritic with irregularly elongated cytoplasmic processes, features common to hepatic stellate cells (HSCs). Double-labeling experiments revealed that the ADAMTS13-positive cells also expressed alpha-smooth muscle actin, confirming that these cells were activated HSCs. These results suggest that HSCs may be major cells producing ADAMTS13 in human liver.  相似文献   
90.
Spinal epidural hematoma is a rare clinical entity, and the literature provides reports of 29 cases so far in Japan. A case of spinal epidural hematoma associated with idiopathic thrombocytopenic purpura diagnosed by CT scan and MRI is reported in detail with references to the literature. A 56-year-old female was admitted to our hospital on April 22, 1990, because of sudden onset of nuchal pain and right hemiparesis. Her consciousness was alert, but the deep tendon reflex was depressed, and pathological reflex such as Babinski's reflex was positive on the right side. Nuchal stiffness was observed. CT scan of the head revealed no abnormality, but the scan of cervical area showed an abnormal high density area in the right posterior region of the spinal cord at C2 - 3 level. MRI also revealed a low intensity area in the same region both in T1 and T2 weighted images. On admission, the platelet count was 10,000/microliters, and the bone marrow aspirate showed abundant megakaryocytes. The patient was diagnosed as having spinal epidural hematoma associated with idiopathic thrombocytopenic purpura. The patient was initially treated with a corticosteroid and a hyperosmotic agent. About 15 hours after the onset, her motor function began improving. Conservative therapy was continued, and she could walk 2 weeks after the onset. Spinal epidural hematoma is an uncommon disease commencing with back and radicular pain, paraplegia and rectovesical insufficiency. Early diagnosis and surgical decompression is generally imperative, although an exceptional remission without operation such as was observed in this case may occur.  相似文献   
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