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171.
An interactive, microcomputer-based karyotype analysis system for phylogenetic cytotaxonomy 总被引:4,自引:0,他引:4
David M. Green James P. Bogart E.H. Anthony D.L. Genner 《Computers in biology and medicine》1980,10(4):219-227
A versatile and practical semi-automatic computerized system of karyotype analysis has been developed for phylogenetic cytotaxonomy for under $4,000. The modular software system is designed for use solely with a small 8-bit microcomputer and requires virtually no custom made hardware. The system interacts with the operator and greatly augments the speed and accuracy of cytotaxonomic investigations. 相似文献
172.
新城疫病毒pIRHN核酸疫苗构建和表达及对肿瘤细胞的影响 总被引:6,自引:0,他引:6
目的:研究NDV HN基因抗肿瘤作用及其可能机制。方法:以 pIRES1neo为表达载体构建了 NDV HN基因的pIRHN核酸疫苗,在体外转染HeLa细胞,用间接免疫荧光和Western blot检测pIRHN在真核细胞中表达状况,用荧光显微镜、DNA琼脂糖电泳及TUNEL染色等方法,检测HN基因导致细胞死亡的类型;用3,5-二羟基甲苯法测定HeLa细胞唾液酸含量的变化。结果:pIRHN 转染HeLa细胞后,能够在真核细胞中表达,能促进肿瘤细胞死亡,其死亡方式主要以诱导细胞凋亡为主,pIRHN使 HeLa细胞唾液酸含量减少。结论:用 NDV HN基因所构建的核酸疫苗能够在真核细胞中高效表达,表达的 HN蛋白主要位于胞膜,胞浆中亦有 HN蛋白表达;pIRHN具有抗肿瘤作用,可能通过其表达产物与肿瘤细胞唾液酸受体的相互作用,发挥其抗肿瘤作用。本实验为迸一步阐明NDV抗肿瘤作用机制提供了理论依据。 相似文献
173.
The neuropathologiesl features of the central nervous system in IS autopsy cases of Japanese male with AIDS were reported. Nine patients had various histological changes including a variety of opportunistic infections in six patients (40%), primary malignant lymphoma of the brain in two (13%), AIDS encephalopathy in four (27%) and vacuolar myelopathy in one (7%). Usually, these pathological changes were present concomitantly. AIDS encephalopathy was characterized by infiltration of mono and multinucleated cells and myelin pallor with astrogliosis located predominantly in the cerebral white matter and subcortical gray matter. Furthermore, unevenly distributed neuronal loss of the cerebral cortex was apparent in one case. Diffuse astrocytosis of the gray matter out of proportion to neuronal loss was also an outstanding finding in another case. The present study suggested that not only the white matter changes but also gray matter alterations might be the morphological substrates of AIDS encephalopathy. 相似文献
174.
Michael Muriello Alexander Y. Kim Krista Sondergaard Schatz Natalie Beck Meral Gunay‐Aygun Julie E. Hoover‐Fong 《American journal of medical genetics. Part A》2019,179(3):410-416
We report three patients with Feingold 2 syndrome with the novel features of growth hormone deficiency associated with adenohypophyseal compression, aortic dilation, phalangeal joint contractures, memory, and sleep problems in addition to the typical features of microcephaly, brachymesophalangy, toe syndactyly, short stature, and cardiac anomalies. Microdeletions of chromosome 13q that include the MIR17HG gene were found in all three. One of the patients was treated successfully with growth hormone. In addition to expanding the phenotype of Feingold 2 syndrome, we suggest management of patients with Feingold 2 syndrome include echocardiography at the time of diagnosis in all patients and consideration of evaluation for growth hormone deficiency in patients with short stature. 相似文献
175.
甘露聚糖结合凝集素(MBL)系胶原凝集素家族成员,是天然免疫系统中的重要分子。血清MBL浓度受其结构基因第一外显子几个点突变的影响和启动子区多态性的调控。MBL基因突变使其血清浓度降低,除导致调理吞噬缺损外,还与自身免疫性疾病如系统性红斑狼疮、类风湿性关节炎、干燥综合征、皮肌炎、克隆病、动脉炎等有关。 相似文献
176.
The naive Bayes model makes the often unrealistic assumption that the feature variables are mutually independent given the class variable. We interpret a violation of this assumption as an indication of the presence of latent variables, and we show how latent variables can be detected. Latent variable discovery is interesting, especially for medical applications, because it can lead to a better understanding of application domains. It can also improve classification accuracy and boost user confidence in classification models. 相似文献
177.
Inflammatory pseudotumor of lymph node and spleen: An entity biologically distinct from inflammatory myofibroblastic tumor 总被引:6,自引:0,他引:6
Jeffery L. Kutok MD PhD Geraldine S. Pinkus MD David M. Dorfman MD PhD Christopher D. M. Fletcher MD FRCPath 《Human pathology》2001,32(12):1382-1387
Inflammatory pseudotumors (IPTs) of the lymph node and spleen are an uncommon, benign cause of lymphadenopathy and/or splenomegaly that often bear striking clinicopathologic similarities to the inflammatory myofibroblastic tumors (IMTs) found in soft tissues. These tumors have classically been grouped together under the umbrella category of "inflammatory pseudotumor." Recent evidence shows that IMTs are in fact neoplastic processes that often harbor balanced chromosomal translocations involving the ALK kinase gene. These translocations result in expression of ALK kinase in IMTs as assessed by immunohistochemical studies. However, the relationship between IMT and IPT of the lymph node and spleen is uncertain. To determine if ALK tyrosine kinase expression is also present in IPT, 13 cases of IPT (9 involving lymph nodes, 4 splenic lesions) were examined for the presence of ALK tyrosine kinase by immunohistochemical staining on paraffin-embedded tissue. In addition, in situ hybridization studies for Epstein-Barr virus--encoded RNAs (EBER) and immunoperoxidase studies for human herpesvirus-8 (HHV8)--specific proteins were performed. All cases had clinical, morphologic, and immunophenotypic findings typical of IPT and had varying proportions of fibroblastic and inflammatory components. Age ranged from 11 to 75 (median, 40) years; 8 subjects were male, and 5 were female. None of the cases (0 of 13) had positive staining for ALK kinase or HHV8, and in 1 a lymph node (1 of 13) was focally positive for EBV (EBER) by in situ hybridization. The absence of ALK kinase as detected by immunohistochemical studies in IPT of the lymph node and spleen suggests that this entity is biologically distinct from the histologically similar IMT. 相似文献
178.
Hiroshi Suemizu Yutaka Tsutsumi Keiichi Watanabe Masahide Kuroki Yuji Matsuoka 《Pathology international》1989,39(12):772-778
Nonspecific cross reacting antigen (NCA), a constituent of the carcinoembryonic antigen family, was localized ultra-structurally in a human lung adenocarcinoma cell line, PC 9. NCA was distributed predominantly on the plasma membrane in the early phases of cell culture. Deletion of fetal bovine serum (FBS) from the culture medium suppressed cell division without significantly altering cell viability, and induced a dramatic but reversible change in NCA localization. Under these conditions, NCA was localized to membrane degradation products within cytoplasmic vesicles and vacuoles. Acid phosphatase activity was also present in some of these intracellular structures. Similar changes in NCA localization were seen in cells cultured with FBS at day 6 when the cells reached a plateau stage of growth. These findings strongly suggest that plasma membrane degradation is accelerated by the cessation of cell growth. Cytoplasmic reactivity for NCA in cancer cells may therefore reflect degradation of plasma membrane-associated NCA and may not necessarily be correlated with increased systhesis of this glycoprotein. Acta Pathol Jpn 39: 772 778, 1989. 相似文献
179.
H. Sinzinger J. Flores F. Rauscha 《Journal of molecular medicine (Berlin, Germany)》1988,66(17):779-783
Summary A screening investigation for the presence of risk factors for the development of atherosclerosis demonstrates a plasma factor deficiency in 0,8% in the Viennese population. These findings are in agreement with the data of a newborn screening performed earlier. All the persons were clinically healthy. In 4 of them at least 1 family member suffered from the same defect. The pathogenetic relevance of the plasma factor defect for thrombophilia at young age is discussed.
Abkürzungsverzeichnis VIP Viennese Initiative for Prostaglandin - PGI2 Prostazyklin - PG Prostaglandin - PF Plasmafaktor - PRP pättchenreiches Plasma - HUS hämolytischurämisches Syndrom - PF4 Plättchenfaktor 4 - TG Thromboglobulin - TXB2 Thromboxan B2 Diese Untersuchung im Rahmen des VIP(VienneseInitiative forProstaglandin)-Screenings wurde vom Medizinisch-Wissenschaftlichen Fonds des Bürgermeisters der Bundeshauptstadt Wien unterstützt 相似文献
Abkürzungsverzeichnis VIP Viennese Initiative for Prostaglandin - PGI2 Prostazyklin - PG Prostaglandin - PF Plasmafaktor - PRP pättchenreiches Plasma - HUS hämolytischurämisches Syndrom - PF4 Plättchenfaktor 4 - TG Thromboglobulin - TXB2 Thromboxan B2 Diese Untersuchung im Rahmen des VIP(VienneseInitiative forProstaglandin)-Screenings wurde vom Medizinisch-Wissenschaftlichen Fonds des Bürgermeisters der Bundeshauptstadt Wien unterstützt 相似文献
180.
A new noninvasive method of measuring the structure and the electrical properties of bilayered biological tissues was evaluated as a potentially useful diagnostic means for detecting changes in subcutaneous tissues. First, the input impedance of an open-ended coaxial probe radiating into a bilayered model was calculated using a full-wave method, the results showed that the evanescen higher order modes do not have a significant influence on the reflection coefficient of muscle layer surface. Then, it was clearly proven that the phase shift and the modulus of the reflection coefficient of muscle layer surface depending on the frequency are useful to estimate the thickness of fat layer and the electrical properties of muscle respectively. The experimental results showed an excellent agreement with the theoretical relationship between the phase shift and the thickness. The sensitivity of estimation of the electrical properties of muscle was shown to be not enough for differentiating between normal and diseased deep tissue because of noises from the experimental systems. 相似文献