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71.
AD Anichkov AV Vodianov SV Mozhaev TN Trofimova VB Nizkovolos AV Obliapin IuZ Polonski? AL Spirin 《Canadian Metallurgical Quarterly》1998,(3):6-9; discussion 9-10
The paper summarizes experience with stereotactic operations by magnetic resonance imaging data by using a Russian OREOL stereotactic manipulator. It describes methods of preoperative preparation of patients by employing diagnostic magnetic resonance tomographs. A number of points of the procedure for identification and localization of deep target structures from magnetic resonance images in parkinsonism, temporal epilepsy and some mental disorders. 相似文献
72.
73.
Current middleware technologies cannot meet the demands of new application areas, such as embedded and mobile systems, that require mechanisms for dealing with a changing environment. This article reviews several approaches for providing adaptive resource management for middleware. Current middleware technologies, such as the Common Object Request Broker Architecture (CORBA) and .NET (http://msdn.microsoft.com/net), mask system and network heterogeneity problems and alleviate the inherent complexity of distributed systems in many application areas. However, the recent emergence of new application areas for middleware, such as embedded systems, real-time systems, and multimedia, imposes challenges that few existing middleware platforms can meet. In particular, because they impose greater resource-sharing and dynamism demands, these application areas require more complex and sophisticated middleware. Resource sharing must be controlled and predictable to ensure that activities running on the same middleware instance have adequate resources. 相似文献
74.
This study evaluated whether human monocyte-derived macrophages synthesize specific types of proteoglycans with lipoprotein-binding capability that could contribute to lipid retention in the arterial wall. After labeling with either [35S]SO4 or [35S]methionine, macrophages secreted a high molecular mass proteoglycan, with glycosaminoglycan chains of approximately 18 kDa and core protein bands of approximately 100 and 55 kDa. Both core protein bands were recognized by an antibody to PG-100, an antibody that recognizes the proteoglycan form of macrophage colony-stimulating factor (PG-100/PG-MCSF). The interaction between PG-100/PG-MCSF and low density lipoproteins (LDL) was examined by gel mobility shift. In this system, PG-100/PG-MCSF was resolved further into two forms. The two forms had the same core proteins but differed in their overall size and glycosaminoglycan content. The larger form contained glycosaminoglycan chains that were entirely chondroitin ABC lyase-sensitive, whereas the smaller form contained chains that were sensitive to both chondroitin ABC lyase and heparinase. Both forms bound native LDL with high affinity, but the larger form bound LDL with higher affinity than the smaller form. The glycosaminoglycan chains of PG-100/PG-MCSF, but not the core proteins, were responsible for binding to native LDL. Mildly oxidized LDL and methyl-LDL, which have an electrophoretic charge similar to that of native LDL, also bound PG-100/PG-MCSF. In contrast, extensively oxidized LDL and acetyl-LDL, which are more electronegative than native LDL, did not bind to either form of PG-100/PG-MCSF. The demonstration of two forms of human monocyte-derived macrophage PG-100/PG-MCSF which bind LDL may represent an additional role for macrophages in the extracellular trapping of lipoproteins in atherosclerosis. 相似文献
75.
KP Williams XH Liu TN Schumacher HY Lin DA Ausiello PS Kim DP Bartel 《Canadian Metallurgical Quarterly》1997,94(21):11285-11290
In vitro selection experiments have produced nucleic acid ligands (aptamers) that bind tightly and specifically to a great variety of target biomolecules. The utility of aptamers is often limited by their vulnerability to nucleases present in biological materials. One way to circumvent this problem is to select an aptamer that binds the enantiomer of the target, then synthesize the enantiomer of the aptamer as a nuclease-insensitive ligand of the normal target. We have so identified a mirror-image single-stranded DNA that binds the peptide hormone vasopressin and have demonstrated its stability to nucleases and its bioactivity as a vasopressin antagonist in cell culture. 相似文献
76.
F Coulin CA Power S Alouani MC Peitsch JM Schroeder M Moshizuki I Clark-Lewis TN Wells 《Canadian Metallurgical Quarterly》1997,248(2):507-515
The aim of this study was to determine the level of endogenous prostaglandin E2 (PGE2), prostaglandin F1 alpha (6-keto-PGF1 alpha) and thromboxane B2 (TXB2) in the gastric and duodenal mucosa of patients with duodenal ulcer and duodenitis. Besides, the investigation aimed at determining the effect of smoking and infection by Helicobater pylori on prostaglandin synthesis. The investigation comprised 62 patients with duodenal ulcer, 46 patients with duodenitis and 44 controls. The results of our investigation indicate that the decreased prostaglandin synthesis in gastric and duodenal mucosa determined in patients with duodenal ulcer may have a considerable role in development of duodenal ulcer. Furthermore, the harmful effects of smoking on the gastric and duodenal mucosa may be mediated by the decreased prostaglandin synthesis in the gastric and duodenal mucosa. However, Helicobacter pylori seems to affect the development of duodenal ulcer through other mechanisms. 相似文献
77.
78.
It is 100 years since the electron was discovered by J.J. Thomson. In this paper, the author reviews the life and work of a man who transformed the view of the fundamental constituents of matter, laying the foundations for modern electronics 相似文献
79.
Functional analysis of a transactivation domain in the thyroid hormone beta receptor 总被引:1,自引:0,他引:1
Y Tone TN Collingwood M Adams VK Chatterjee 《Canadian Metallurgical Quarterly》1994,269(49):31157-31161
80.
EM De Vries DO Ricke TN De Vries A Hartmann H Blaszyk D Liao T Soussi JS Kovach SS Sommer 《Canadian Metallurgical Quarterly》1996,7(3):202-213
Germline and somatic mutations in the p53 and APC genes contribute to neoplasia. The patterns of these and other acquired mutations in cancers reflect environmental mutagens and endogenous factors that contribute to carcinogenesis. Herein, we describe a database of almost 2,300 mutations in the p53 and APC genes published until September 1, 1993. In addition to cataloging the mutations, multiple fields of information have been added to facilitate future molecular epidemiological analyses of human cancer. The accuracy of the database has been checked by the present authors and, by soliciting feedback from the original corresponding authors. The strengths and limitations of the primary literature are discussed. 相似文献