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71.
Neural stem cells are present both in the developing nervous system and in the adult nervous system of all mammals, including humans. Little is known, however, about the extent to which stem cells in adults can give rise to new neurons. We used immunocytochemistry, electron microscopy, fluorescence microscopy (FM imaging) and electrophysiology to demonstrate that progeny of adult rat neural stem cells, when co-cultured with primary neurons and astrocytes from neonatal hippocampus, develop into electrically active neurons and integrate into neuronal networks with functional synaptic transmission. We also found that functional neurogenesis from adult stem cells is possible in co-culture with astrocytes from neonatal and adult hippocampus. These studies show that neural stem cells derived from adult tissues, like those derived from embryonic tissues, retain the potential to differentiate into functional neurons with essential properties of mature CNS neurons.  相似文献   
72.
原位PCR技术检测石蜡包埋脑组织中人巨细胞病毒DNA   总被引:6,自引:0,他引:6  
应用原位聚合酶链反应(ISPCR)技术检测了25例尸检畸形胎儿石蜡包埋脑组织中人巨细胞病毒(HCMV)DNA,并与普通PCR及原位杂交(ISH)进行了比较。ISPCR、PCR及ISH检测阳性率分别为44%,36%及20%。与ISH相比较,ISPCR不仅检出阳性率高,而且信号强度增强。研究结果提示,IS-PCR是诊断HCMV感染的快速、敏感、特异的实用方法。  相似文献   
73.
Summary.  We have evaluated PCR–RFLP as a practical method for rapid typing of enteroviruses causing aseptic meningitis in Korea. Through blind examination of 80 clinical isolates from patients with aseptic meningitis, we have compared the results of conventional serotyping with PCR–RFLP based genotyping, which was developed for this study. Among the 80 case isolates, which had been previously typed by routine neutralization test, only 42 cases (52.5%) were matched with typing by PCR–RFLP. The result clearly demonstrated that the enterovirus serotype does not coincide with the genotype. Therefore, the classification of enteroviruses by genotyping with PCR–RFLP, although rapid and simple, may be complicated by regional or seasonal differences. However, the PCR–RFLP method developed in this study is applicable to the epidemiological study of enteroviruses when regional or seasonal differences exist, and is useful in identifying the source of an infection. Received August 6, 2001; accepted April 15, 2002 Published online July 10, 2002  相似文献   
74.
18例恶性苗勒混合瘤临床病理分析   总被引:1,自引:0,他引:1  
目的:探讨女性生殖系统恶性苗勒混合瘤(MMMT)的临床与病理特征。方法:对18例女性生殖系统MMMT进行光镜观察及免疫组化染色,结合临床资料进行分析,对9例进行了术后随访。结果:各部位MMMT的形态特征相似,均含有上皮及间叶两种组织成分,相互间有穿插和移行变化,组织成分形态多样,免疫组化有助于判断。恶性度与异型性、核分裂数及出血坏死程度有关。预后与临床分期有关。化疗有效。结论:MMMT的诊断主要依据组织形态学,预后与临床分期有关。  相似文献   
75.
Inflammatory bowel disease (IBD) is commonly associated with arthritic manifestations. They are divided into three clinical categories; peripheral arthritis, spondylitis, and sacroiliitis. To evaluate the incidence of arthritis associated with IBD in Korea, we retrospectively reviewed one hundred and twenty-nine patients with IBD, 77 with ulcerative colitis (UC) and 52 with Crohn''s disease (CD). Arthritis occurred in twenty-two patients (17.1%); 15 with UC(19.6%), 7 with CD (13.5%). Patients with arthritis had more active inflammations and all were seronegative except one patient. Peripheral arthritis was found in twenty patients (15.5%) and more common in UC (19.6%) than in CD (9.6%). Joint involvements tended to be monoarticular or pauciarticular, and most frequently developed in the knee and ankle. Spondylitis was diagnosed in one patient (1.6%) who showed HLA B27 positivity. Radiographic sacroiliitis was observed in eight patients (6.2%) who revealed HLA B27 negativity. Both peripheral arthritis and sacroiliitis were found in six patients (4.6%). In CD, arthritis occurred in 20% of the patients with colonic involvement but in none of the patients without colonic involvement. In conclusion, arthritis was frequent in patients with IBD. Peripheral arthritis was more common in patients with UC than CD. All the patients with CD and arthritis had colonic involvement.  相似文献   
76.
The anterior eye chamber and the kidney capsule of the mouse have been traditionally used for long-term culture of tooth germ grafts. However, although these sites provide an excellent growth environment, they do not represent real in situ sites for the development of a grafted tooth germ. Here, we describe a protocol to transplant a tooth germ into the mandibular diastema region of mouse embryos using exo utero surgery. Our results demonstrate that the mouse embryonic diastema region represents a normal physiological environment for the development of transplanted tooth germs. Transplanted tooth germs developed synchronically with and became indistinguishable from the endogenous ones. These ectopic teeth were vascularized and surrounded with nerve fibers, and were able to erupt normally. Thus, the exo utero transplantation approach will provide a new avenue to study tooth development and regeneration.  相似文献   
77.
Klinefelter syndrome (KS) is often associated with various neoplasms, especially germ cell tumors. Mediastinum is the most favored site of extragonadal germ cell tumors with KS, which is somewhat different from those without KS. The retroperitoneal germ cell tumor in KS is very rare. A five-month-old boy with an abdominal mass was found to have a retroperitoneal tumor. After surgical removal, he was diagnosed to have mature cystic teratoma. Cytogenetic study of his peripheral lymphocytes revealed that his karyotype was consistent with KS. This case suggests that patients with KS might be at risk of having germ cell tumors in sites other than mediastinum. It also suggests that all cases with these tumors should be screened for the presence of karyotypic abnormalities, and it might help to assess the exact correlation between germ cell tumors and KS, and to treat them accordingly.  相似文献   
78.
Arterial intima proteins were extracted by 9 M urea from matching histologically atheroma-free areas of 27 human thoracic aortas of both sexes from younger (15-34) and older (35-82) age groups and studied after separation by high-resolution two-dimensional polyacrylamide gel electrophoresis. Seventeen specific protein groups on each gel were identified according to their relative charges and molecular weights and their distribution in the two age groups compared. Some plasma-derived proteins occurred rarely in young aortas while they were consistently found in those from older cases, i.e., protein group 4 (alpha 1-antichymotrypsin) 1/13 (8%) vs 12/14 (86%), group 7 (haptoglobin beta-chain) 1/13 (8%) vs 13/14 (93%) and groups 6 and 9 (IgG chains) 3/13 (23%) vs 9/14 (64%), respectively. Other plasma-derived proteins such as group 3 (albumin) and 5 (alpha 1-antitrypsin) were identified in all samples of both age groups but their expression in the aortic intima increased with age. Proteins which are typically found intracellularly such as those from groups 11 (actin), 12 (cytoskeleton proteins), and 13 (tropomyosin-like proteins) appeared in samples of intima of both age groups but were less apparent in older specimens. These studies suggest that the changes in aortic intima protein distribution in the absence of atherosclerosis closely correlate with histological changes such as intimal thickening often found with aging, providing new sensitive markers of vascular senescence.  相似文献   
79.
神经导航中脑组织变形补偿的点云处理   总被引:1,自引:0,他引:1  
有限元方法是解决神经导航中脑组织变形的重要方法,需要手术过程中的脑皮层信息作为其边界条件.本文通过非结构点云进行了脑皮层信息的表示,并通过对其进行处理来获取有限元方法的边界条件.点云处理包括纹理映射、分割、简化和去噪,其中非结构点云的简化与去噪采用了改进的基于表面特性k邻域的聚类方法.实验结果证明所采用的点云处理方法是可靠的.  相似文献   
80.
Oxidative stress has been implicated in several diseases, including cancer. Oxidants induce oncogenes and their products associated with cell growth. Even though epidemiological studies implicate oxidants in promoting cancer, there is still a lack of in vivo evidence for the same. In this study, we measured the levels of myeloperoxidase (MPO), an enzyme associated with oxidation and autoantibodies to lipid peroxide-modified protein (LOOH-RSA), in the plasma of subjects with gynecological cancers. The gynecological cancer subjects (n = 201) had higher plasma MPO and LOOH-RSA levels compared with control subjects (n = 60). Immunohistochemical analysis of tissues revealed that immunostaining for MPO and LOOH-RSA was higher in cancer tissues compared with controls. The staining was specific to cell types and not ubiquitously present. Neutrophils, monocytes/macrophages, and natural killer cells have been proposed to play a role in cancer promotion and progression. This study proposes a role for oxidative stress and especially MPO in cancer.  相似文献   
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