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11.
A PCR-based assay to identify Streptococcus gallolyticus has been developed. The assay uses an oligonucleotide primer pair targeting a partial sequence of the manganese-dependent superoxide dismutase gene (sodA). The assay distinguished members of the S. gallolyticus group from other, closely related taxa successfully by yielding a 408-bp specific amplicon.  相似文献   
12.
A rare case of an alveolar soft part sarcoma of the uterine cervix in an 8 year old girl is presented. The patient was admitted because of genital bleeding lasting for 7 months. A polypoid tumor, 2times1.5 cm in diameter, was found in her external uterine os and was surgically resected. Microscopically, the tumor consisted of a uniform sheet of tumor cells in the cytoplasm which contained granules and which were stained with periodic acid-Schiff, both before and after the diastase digestion. Alveolar arrangement of the tumor cells was manifested with reticulin silver impregnation. Dense, membrane bound granules were evident at an ultrastructural level in the cytoplasm of the tumor cells. An immunohistochemical examination demonstrated a positive reaction for anti-desmin, anti-myoglobin, anti-HHF35 and anti-neuron specific enolase in the cytoplasm.  相似文献   
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14.
Medullasin levels in granulocytes of patients with neurological diseases and healthy volunteers were determined by the enzyme immunoassay using mouse monoclonal antibodies against human medullasin and o-phenylenediamine-H2O2 as the detection system of the enzyme activity. One hundred twenty-one out of 159 patients with multiple sclerosis (76.1%) showed positive results (above means of normals + 2SD) in this test, while only 16.9% (24/142) of patients with non-inflammatory neurological diseases had positive results. This enzyme immunoassay method for medullasin is considered to be an useful paraclinical test for the diagnosis of multiple sclerosis.  相似文献   
15.
Decellularized ureter for tissue-engineered small-caliber vascular graft   总被引:1,自引:1,他引:1  
Previous attempts to create small-caliber vascular prostheses have been limited. The aim of this study was to generate tissue-engineered small-diameter vascular grafts using decellularized ureters (DUs). Canine ureters were decellularized using one of four different chemical agents [Triton-X 100 (Tx), deoxycholate (DCA), trypsin, or sodium dodecyl sulfate (SDS)] and the histology, residual DNA contents, and immunogenicity of the resulting DUs were compared. The mechanical properties of the DUs were evaluated in terms of water permeability, burst strength, tensile strength, and compliance. Cultured canine endothelial cells (ECs) and myofibroblasts were seeded onto DUs and evaluated histologically. Canine carotid arteries were replaced with the EC-seeded DUs (n = 4). As controls, nonseeded DUs (n = 5) and PTFE prostheses (n = 4) were also used to replace carotid arteries. The degree of decellularization and the maintenance of the matrix were best in the Tx-treated DUs. Tx-treated and DCA-treated DUs had lower remnant DNA contents and immunogenicity than the others. The burst strength of the DUs was more than 500 mmHg and the maximum tensile strength of the DUs was not different to that of native ureters. DU compliance was similar to that of native carotid artery. The cell seeding test resulted in monolayered ECs and multilayered alpha-smooth muscle actin-positive cells on the DUs. The animal implantation model showed that the EC-seeded DUs were patent for at least 6 months after the operation, whereas the nonseeded DUs and PTFE grafts become occluded within a week. These results suggest that tissue-engineered DUs may be a potential alternative conduit for bypass surgery.  相似文献   
16.
目的 探讨隆突性皮纤维肉瘤(DFSP)中肌样/肌纤维母细胞性分化的本质及其临床病理学意义。方法 采用常规HE切片对124例DFSP进行筛选,对6例伴有肌样/肌纤维母细胞性分化的DFSP病例进行免疫组织化学标记,其中2例加做电镜检测。结果 肌样/肌纤维母细胞性分化多出现在纤维肉瘤型DFSP(FS-DFSP)中,表现为肿瘤周边部或肿瘤内散在性分布的深嗜伊红色小结节或短要束,由梭形细胞组成,细胞多无异型性,核分裂象也罕见,形态上似平滑肌细胞或肌纤维母细胞。免疫组织化学标记显示肌样区域细胞表达α-平滑肌肌动蛋白和肌物质特异性肌动抗原,不表达CD34;电镜观察证实细胞含有质膜下微丝束、局灶性致密体及微胸饮囊泡样结构,与肌纤维母细胞相一致,结论 DFSP中的肌样/肌纤维母细胞性分化可能是间质中肌纤维母细胞增生的结果,并非代表了瘤细胞的真性肌纤维母细胞性分化。  相似文献   
17.
Gangliosides, a family of glycosphingolipids that contain sialic acid, are abundant on the neuronal cell membranes, but their precise functions in the central nervous system remain largely undefined. In a previous study of GalNAc-T(-/-) mice engineered to lack beta1,4-N-acetylgalactos-aminyltransferase (GM2/GD2 synthase) to abolish any, complex gangliosides, we observed the reduction of nerve conduction velocity but did not find any obvious morphological change in the brain. In the present study, we observed morphological changes in the nerve fiber tracts of the spinal cord in these mice. In GalNAc-T(-/-) mice, the number of degenerated axons was markedly increased in the dorsal funiculus, tract of Lissauer, and dorsolateral funiculus of the cervical segment of the spinal cord as well as the dorsal funiculus and tract of Lissauer of the lumbar segment of the spinal cord. There were also increased numbers of unmyelinated fibers in GalNAc-T(-/-) mice. Loosened myelin sheaths and myelin sheaths separated from axons by wide spaces were also observed in GalNAc-T(-/-) mice. These results provide a morphological basis for the previously observed reduction in the nerve conduction velocity and suggest that complex gangliosides are essential for the maintenance of myelin and the integrity of nerve fibers of the spinal cord.  相似文献   
18.
We evaluated long-term dynorphin A-immunoreactivity in the rat area postrema (AP) after the administration of cisplatin. First, rats were given 1, 5 and 10 mg/kg body weight cisplatin (i.p.) and their behavior was monitored for 72 h. We observed a delayed increase in pica 24-72 h after injection, compared to the 24 h before injection. We attributed this to the cisplatin injection. Pica was defined as an increase in the intake of non-nutritional matter such as kaolin. Administration of 1, 5 and 10 mg/kg cisplatin led to an increase in kaolin intake on day 1. Administration of 5 and 10 mg/kg of cisplatin led to decreased intake of laboratory chow (MF) on days 1–3, but 10 mg/kg cisplatin causes an excessive aggravation of their condition. Following this behavioral experiment, we immunohistochemically examined the induction of dynorphin A in the AP at 24, 48 and 72 h post-administration of 1 and 5 mg/kg cisplatin. Administration of 5 mg/kg cisplatin caused dynorphin A to accumulate gradually in the neurosoma of the AP neurons, and the numbers of positive AP neurosomata at 48 and 72 h post-administration were higher than following an equal dosage of 0.9% NaCl. These findings suggest that dynorphin A increases in the central nervous system for a long time following administration, and causes certain behavioral and clinical changes, including those related to appetite and nausea.  相似文献   
19.
Early onset familial Alzheimer's disease with spastic paraparesis (FAD-SP) has been associated with mutations of the presenilin 1 gene (PSEN1). We report a pedigree of FAD-SP due to a novel missense mutation of PSEN1 (Y154N). The symptoms of the proband were characterized by presenile dementia in her 40s, preceded by spastic paraparesis in her 30s, whereas the mother of the proband presented with spastic paraparesis in her 40s, followed by symptoms of dementia in her mid 60s. The mutation was found only in the proband, and not in a normal family member, normal Japanese control subjects, patients with sporadic Alzheimer's disease or patients with familial spastic paraparesis without dementia. Thus, Y154N is a novel PSEN1 mutation responsible for FAD-SP of Japanese origin.  相似文献   
20.
In the present study, we established transgenic mice overexpressing Del1, a ligand of integrins, to examine the effect of overexpression of Del1 on vascular morphogenesis. In the wild-type mouse, mesenteric vessels are shaped like rakes consisting of a long stalk and short branches at the periphery. In contrast, those in transgenic mice showed typical dendritic architecture consisting of a few large primary branches with smaller spreading branches. The phenotype of mice overexpressing Del1 suggests the existence of a tissue-specific mechanism for branching morphogenesis in the mesentery.  相似文献   
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