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191.
A polyhedron P is castable if its boundary can be partitioned by a plane into two polyhedral terrains. Castable polyhedra can be manufactured
easily using two cast parts, where each cast part can be removed from the object without breaking the cast part or the object.
If we assume that the cast parts are each removed by a single translation, it is shown that for a simple polyhedron with n vertices, castability can be decided in time and linear space using a simple algorithm. A more complicated algorithm solves the problem in time and space, for any fixed ε > 0. In the case where the cast parts are to be removed in opposite directions, a simple O(n
2
)-time algorithm is presented. Finally, if the object is a convex polyhedron and the cast parts are to be removed in opposite
directions, a simple algorithm is presented.
Received June 1, 1994; revised May 25, 1995. 相似文献
192.
A 20-year-old man presented with signs of thornapple intoxication: restlessness, disorientation, hallucinations, euphoria, and furthermore dry and red skin and symmetrical dilation of the pupils. Thornapple intoxication mimics atropine intoxication. Thorn apples (Datura stramonium) are seemingly becoming popular as a hallucinogenic drug. When the symptoms are mild gastric lavage leaving active charcoal in the stomach afterwards will suffice. In case of severe symptoms treatment with physostigmine is indicated. 相似文献
193.
YM Graus JJ Verschuuren NA Bos PJ van Breda Vriesman MH De Baets 《Canadian Metallurgical Quarterly》1993,43(1-2):113-124
The immunoglobulin heavy chain (VH) gene family usage in experimental autoimmune myasthenia gravis (EAMG) model was investigated by RNA slot blot hybridization using VH gene family specific probes. Anti-acetylcholine receptor (AChR) monoclonal antibodies (mAbs) isolated from susceptible C57BL/6 and resistant BALB/c mice were found to be encoded by VH genes from at least six different families. The Vgam3.8 family was overrepresented in alpha-bungarotoxin blocking mAbs. Expression of cross-reactive idiotypes by anti-AChR mAbs was irrespective of the VH gene family usage. Strain dependent differences in susceptibility for EAMG were not reflected in an aberrant VH gene family usage of anti-AChR mAbs. 相似文献
194.
LJ Rijks JC van den Bos PA van Doremalen GJ Boer K de Bruin T Doornbos JA Vekemans MA Posthumus AG Janssen EA van Royen 《Canadian Metallurgical Quarterly》1998,25(4):411-421
We have synthesized and evaluated E-11beta-nitrato-17alpha-iodovinylestradiol (E-NIVE; E-3c) and its 123I-labelled form, as a new potential radioligand for imaging of estrogen receptor (ER)-positive human breast tumors. E-[123I]NIVE was prepared by stereospecific iododestannylation of the E-tri-n-butylstannylvinyl precursor (E-2c), obtained from reaction of 11beta-nitrato-estrone (8) with E-tributylstannylvinyllithium. In competitive binding studies, E-NIVE proved to have high binding affinity for both the rat and the human ER (Ki 280-730 pM), without significant binding to human sex hormone binding globulin. Distribution studies in normal and mammary tumor-bearing rats showed specific ER-mediated uptake of E-[123I]NIVE in the estrogen target tissues, i.e., uterus, ovaries, pituitary, and hypothalamus, but not in the mammary tumors. Selective retention in these target tissues, including tumor tissue, resulted in significant increases over time for the target tissue-to-muscle uptake ratios, but not for the target tissue-to-fat uptake ratios. The tumor-to-fat uptake ratio even appeared constantly below 1. In the primary estrogen target tissues, E-[123I]NIVE displayed high specific ER-mediated uptake and retention, which resulted in moderate target-to-nontarget tissue uptake ratios. In contrast, in tumor tissue, E-[123I]NIVE uptake appeared to be rather low and not ER-specific. As a consequence, E-[123I]NIVE appears to be a less favorable radioligand for ER imaging in breast cancer than the previously studied stereoisomers of 11beta-methoxy-17alpha-[123I]iodovinylestradiol (E- and Z-[123I]MIVE; [123I]E- and [123I]Z-3b). 相似文献
195.
196.
197.
F van Langevelde R D Vis K N?nt?-Salonen T Halme P Pakarinen H Hy?r? K Vuorinen V N?nt? 《The Science of the total environment》1985,42(1-2):171-180
Changes in the metabolism of copper and zinc are described in aspartylglycosaminuria (AGU) patients. AGU patients had significantly reduced serum zinc concentrations. However, hair zinc levels were normal, and hyperzincuria could not be demonstrated. The copper content in the hair of AGU patients was highly elevated. Serum copper and ceruloplasmin concentrations were within normal range. In AGU, small-molecular-weight glycoasparagine storage products accumulate in tissues and are excreted in urine in large amounts. They may interfere with the transport mechanisms of trace elements, and thus alter their distribution and availability for tissues. The changes in copper and zinc levels may contribute to the pathogenesis of some of the clinical signs of AGU and Salla disease. 相似文献
198.
M. van der Kraan M.V. Fernandez Cid G.F. Woerlee W.J.T. Veugelers C.J. Peters G.J. Witkamp 《The Journal of Supercritical Fluids》2007,40(3):336-343
When natural fibres are dyed in supercritical carbon dioxide, the addition of a small amount of water increases coloration. For a process design it is important to know how much water has to be added to obtain a desired humidity of both textile and carbon dioxide. In this work a thermodynamic model is proposed to calculate the distribution of water over the textile phase and the supercritical phase as a function of pressure and temperature. The phase equilibrium is described with Raoult's law for non-ideal fluids. The absorbed water in the textile is a condensed phase and is modelled here as a non-ideal liquid, using the NRTL-equation. The non-ideality of the supercritical phase is described by a solubility enhancement factor, a new equation derived from statistical thermodynamics. Although the model is applied to cotton, viscose, silk and wool, it can be used for all water absorbing textiles. 相似文献
199.
FA van de Klundert ML Gijsen PR van den IJssel LH Snoeckx WW de Jong 《Canadian Metallurgical Quarterly》1998,75(1):38-45
OBJECTIVES: The aim of this study was to determine (a) whether delay in femur fracture stabilization beyond twenty-four hours in patients with head injury increased the risk of pulmonary complications and (b) whether immediate (up to twenty-four hours) femur fracture stabilization increased the risk of central nervous system (CNS) complications. DESIGN: Retrospective analysis. MATERIALS AND METHODS: Thirty-two patients with femur fracture and head injury were identified. Fourteen underwent immediate stabilization of their fractures, and eighteen underwent delayed (four-teen patients) or no (four patients) stabilization of their fractures. RESULTS: In the immediate stabilization group, five patients had severe head injuries [Glasgow Coma Score (GCS) < or = 8] and nine had mild head injuries (GCS > 8). In the mild head injury group, no patient had a pulmonary complication and one had a CNS complication. In the severely head-injured group, one patient had a pulmonary complication and no patient had a CNS complication. In the delayed stabilization group, six patients had mild head injuries (GCS > 8) and twelve had severe head injuries (GCS < or = 8). In the mildly head injured group, one patient had a pulmonary complication, two patients had CNS complications, and one patient died. In the severely head injured group, nine patients had pulmonary complications, three patients had CNS complications, and one patient died. Logistic regression identified delay in femur stabilization as the strongest predictor of pulmonary complication (p = 0.0042), followed by severity of chest Abbreviated Injury Score (AIS; p = 0.0057) and head AIS (p = 0.0133). Delaying fracture stabilization made pulmonary complications forty-five times more likely. Each point increase in the chest AIS and head/neck AIS increased the risk of pulmonary complication by 300 percent and 500 percent, respectively. A statistically significant predictor of CNS complications could not be identified by using logistic regression. CONCLUSION: Delay in stabilization of femur fracture in head-injured patients appears to increase the risk of pulmonary complications. However, due to selection bias in this patient sample, this question cannot be definitively answered. Early fracture stabilization did not increase the prevalence of CNS complications. 相似文献
200.