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71.
E G Jung 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1989,40(12):761-762
"Schnyder's rule" states that multiple tumours of the skin are dominantly inherited, whereas solitary tumours of the same histological type are noninherited. This rule may be extended to cover segmental cases representing somatic mutations. 相似文献
72.
To test the hypothesis that complement-mediated cell lysis and cell-mediated cytotoxicity operate by analogous mechanisms, cell membranes from two antibody-dependent cytotoxicity systems were examined by electron microscopy after negative staining. Ring-shaped membrane lesions generally similar to, but larger than, those previously described for complement lysis were observed. These findings are in agreement with recent measurements of larger functional pores for ADCC than complement. 相似文献
73.
Yu-Sheng Chang Pao-Hsien Chu Shih-Ming Jung Kun-Eng Lim Jaw-Ji Chu Chuen Hsueh Ying-Shiung Lee 《Cardiovascular pathology》2005,14(2):104-106
Cardiac papillary fibroelastoma (CPF) is the second most common benign neoplasm of the heart. This study describes the case of an 81-year-old man who was admitted to the hospital for severe vertigo and in whom a tumor at the right ventricular outflow tract (RVOT) was identified incidentally during echocardiography. The CPF was excised smoothly following the confirmation of its position by computed tomography. The comprehensive pathologic findings of CPF were reviewed. Detailed immunohistochemical analyses of CD34 and factor VIII-related antigen were performed on the covering endocardial cells. The unique chondroid metaplasia of fibrous tissue in this CPF has never been reported. This work is the first to present an unusual CPF at the RVOT with reactive process of fibrous connective tissue. 相似文献
74.
Lee J Kim MS Park C Jung EB Choi DH Kim TY Moon SK Park R 《Immunopharmacology and immunotoxicology》2004,26(1):17-28
This study is designed to investigate the effect of morphine on glutamate-induced toxicity of primary rat neonatal astrocytes. Glutamate decreases the intracellular GSH level, and thereby induces cytolysis of astrocytes and C6 glial cells accompanied by apoptotic features. Glutamate-induced cytotoxicity is protected by morphine and antioxidants such as GSH and NAC, whereas MK-801, an antagonist of glutamate receptor NMDA does not protect astrocytes against glutamate toxicity. Also, morphine antagonist, naloxone, as well as selective ligands for opioid receptor subtypes, including DAMGO, DPDPE, and U69593, do not inhibit the protective effect of morphine on glutamate-induced cytotoxicity. Morphine significantly prevents the depletion of GSH by glutamate and thereby inhibits the generation of H2O2 in a dose-dependent manner. Furthermore, morphine prevents the change of mitochondrial permeability transition by glutamate. Taken together, we suggest that morphine protects the primary rat neonatal astrocytes from glutamate toxicity via modulation of intracellular redox status. 相似文献
75.
Green Steven; Fishel Simon; Hall Jenny; Hunter Alison; Fleming Steven; Hobson Geoffrey; Roe Heather; Dowell Ken; Thornton Simon; Klentzeris Lucas 《Human reproduction (Oxford, England)》1995,10(6):1430-1434
Utilizing real-time computer image analysis, individual spermatozoawere selected using microaspiration. Selection criteria werebased on potential hyperactivation motility characteristics;the amplitude of lateral head displacement >7.5 µm,curvilinear velocity >70 µm/s and linearity of <30%.For this pilot study, 16 patients (eight in each group) wererecruited. Using subzonal insemination (SUZI), up to five (mean= 4.4 ± 0.3) spermatozoa selected using computer-imagesperm selection (CISS) were microinjected, or up to 15 (mean= 12.8 ± 1.3 SD) unselected spermatozoa. In the groupwhich utilized CISS, 28 out of 49 (57%) oocytes were fertilizedcompared with 13 out of 52 (25%) utilizing conventional SUZI(P < 0.04); polyspermy was 20% (n = 10) and 2% (n = 1) respectively.CISS with SUZI showed increased efficiency in achieving fertilizationand is a novel approach to studying individual sperm functionin a sperm egg bioassay where gamete ratios are close to unity. 相似文献
76.
Peptide motifs of closely related HLA class I molecules encompass substantial differences. 总被引:11,自引:0,他引:11
Olaf Rtzschke Kirsten Falk Stefan Stevanovi Günther Jung Hans-Georg Rammensee 《European journal of immunology》1992,22(9):2453-2456
The peptides presented by major histocompatibility complex class I molecules adhere to strict rules concerning peptide length and occupancy by certain amino acid residues at anchor positions. Peptides presented by HLA-A*0201 molecules, for example, are generally nonapeptides requiring Leu or Met at position 2 and an aliphatic residue, predominantly Val, at position 9. A closely related molecule, HLA-A*0205, differing from the former at four amino acid residues, has a related but substantially different peptide motif. A*0205-presented peptides are still nonapeptides, and position 9 is still aliphatic, although it is preferentially occupied by Leu instead of Val. Position 2 not only allows aliphatic residues but also polar ones. Occupancy at position 6, considered as an auxiliary anchor in A*0201, as well as non-anchor residues at positions 3, 4, and 8 are relatively well conserved between the two peptide motifs. Thus, although a number of the T cell epitopes presented by the two HLA-A2 forms is expected to be identical, a considerable number of epitopes should be different. 相似文献
77.
Intravitreal injection of human recombinant tumor necrosis factor-alpha (TNF) induced inflammation in the rabbit eye characterized by dilation of blood vessels in the iris, disruption of the blood-ocular barriers, infiltration of inflammatory cells into the anterior chamber, and accumulation of prostaglandin E in intraocular fluids. Inflammation first appeared on day 1, increased on day 2, and remained elevated on day 7. The inflammatory eell infiltrate in the anterior segment of the eye was largely monocytic on days 1 and 2; by day 7 large numbers of lymphocytes were also present. TNF-induced ocular inflammation therefore differed from that reported for intravitreally injected endotoxin in terms of time course and the types of inflammatory cells in the aqueous humor. In a series of experiments in which combinations of TNF and endotoxin were used, intravitreal injection of TNF, 24 h after a low dose ofEscherichia coli endotoxin, produced no more inflammation than that produced by TNF following an injection of endotoxin vehicle. However, if TNF was injected 24 h before endotoxin, the resulting inflammation was greater than that observed in animals given TNF followed by endotoxin vehicle. 相似文献
78.
Construction and characterization of affibody-Fc chimeras produced in Escherichia coli 总被引:1,自引:0,他引:1
Rönnmark J Hansson M Nguyen T Uhlén M Robert A Ståhl S Nygren PA 《Journal of immunological methods》2002,261(1-2):199-211
Affibody-Fc chimeras were constructed by genetic fusion between different affibody affinity proteins with prescribed specificities and an Fc fragment derived from human IgG. Using affibody ligands previously selected for binding to respiratory syncytial virus (RSV) surface protein G and Thermus aquaticus (Taq) DNA polymerase, respectively, affibody-Fc fusion proteins showing spontaneous Fc fragment-mediated homodimerization via disulfide bridges were produced in Escherichia coli and affinity purified on protein A Sepharose from bacterial periplasms at yields ranging between 1 and 6 mg/l culture. Further characterization of the chimeras using biosensor technology showed that the affibody moieties have retained high selectivities for their respective targets after fusion to the Fc fragment. Avidity effects in the target binding were observed for the affibody-Fc chimeras compared to monovalent affibody fusion proteins, indicating that both affibody moieties in the chimeras were accessible and contributed in the binding. Fusion of a head-to-tail dimeric affibody moiety to the Fc fragment resulted in tetravalent affibody constructs which showed even more pronounced avidity effects. In addition, the Fc moiety of the chimeras was demonstrated to be specifically recognized by anti-human IgG antibody enzyme conjugates. One application for this class of "artificial antibodies" was demonstrated in a western blotting experiment in which one of the anti-RSV surface protein G affibody-Fc chimeras was demonstrated to be useful for specific detection of the target protein in a complex background consisting of a total E. coli lysate. The results show that through the replacement of the Fab portion of an antibody for an alternative binding domain based on a less complicated structure, chimeric proteins compatible with bacterial production routes containing both antigen recognition domains and Fc domains can be constructed. Such "artificial antibodies" should be interesting alternatives to, for example, whole antibodies or scFv-Fc fusions as detection devices and in diagnostic or therapeutic applications. 相似文献
79.
Oh S Yoon YW Jang GJ Ahn JB Hong Gp Gang Gh Gang MS Hong Yu Gee JH 《Journal of Korean medical science》2003,18(4):589-591
We report a case of ruptured mycotic aneurysm involving innominate artery requiring an urgent surgical treatment. A 62-yr-old woman presented with fever and dyspnea. Previously, she was diagnosed with colon cancer and received right hemicolectomy and one cycle of adjuvant chemotherapy. On echocardiogram, pericardial effusion was noted and emergency pericardiocentesis was performed. CT scan revealed aortic aneurysm involving ascending aorta and innominate artery, and thrombi surrounding those structures. Patch repair of the defect in the ascending aorta and ringed Goretex graft to bypass the innominate and ascending aorta were performed. We believe that this is the first case of ruptured mycotic aneurysm involving innominate artery. 相似文献
80.
Localized in vivo proton magnetic resonance spectroscopy ((1)H-MRS) has been used to measure the metabolic status of the human brain in a non-invasive manner; thus, it is often called "a non-invasive biochemical assay". MRS is more sensitive than magnetic resonance imaging (MRI) in detecting ischemic damage by measuring the metabolic changes that occur prior to the anatomic changes. We report a patient who presented with innominate artery occlusion and symptoms of posterior circulation insufficiency and showed favorable metabolic changes by (1)H-MRS after revascularization. He showed no visible lesion in brain MRI, but in (1)H-MRS, decreased N-acetylaspartate (NAA) signal was noted in a resting state.After revascularization, both symptomatic improvement and recovery of NAA signal were observed. (1)H-MRS may provide valuable clinical information in diagnosis and management of cerebral hypoperfusion at a much earlier stage prior to the anatomic changes. 相似文献