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61.
Antitumor polyacetylenic alcohol, panaxynol, was isolated and purified from a powder of the root of Panax ginseng C.A. Meyer. Panaxynol inhibited the growth of various kinds of cultured tumor cell lines in a dose-dependent manner. In this paper we demonstrated the first specific antibody production against panaxynol. Anti-panaxynol antibody was elicited in rabbits by immunization with panaxynol hemisuccinate-bovine serum albumin conjugate (panaxynol hemisuccinate-BSA conjugate). An enzyme immunoassay (EIA) for the determination of panaxynol was established using a double-antibody technique. The EIA was highly specific against panaxynol although the antibody showed a minimal cross-reactivity with other types of polyacetylenic alcohol, i.e. panaxydol (12.0%) and panaxytriol (0.77%). Panaxynol at a concentration as low as 6.4 ng/ml can be detected. Using this assay we reconfirmed the rapid consumption of panaxynol by target tumor cells in an in vitro-culture system. The anti-panaxynol antibody may be a valuable tool for studies of the biological properties of polyacetylenic compounds.  相似文献   
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63.
Crystal phase transition between the low- and high-temperature phases has been investigated for ethylene (E)-tetrafluoroethylene (TFE) alternating copolymer (ETFE) containing the third monomeric species by the temperature dependent measurements of wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) and differential scanning calorimetry. Nonafluoro-1-hexene (NFH) and hexafluoropropylene (HFP) were chosen as the third monomers, where they are different in the side-branch length, -(CF2)3CF3 and -CF3, respectively. In the case of E/TFE/NFH copolymer (ET-C4F9), the crystal phase transition temperature of the original ETFE two-components copolymer was not very much affected by the existence of NFH in the range of NFH content from 0.7 to 3 mol%. Contrarily, the crystal phase transition temperature of E/TFE/HFP copolymer (ET-CF3) was found to decrease drastically with increasing HFP content. The melting temperature and the higher-order structure were also affected sensitively depending on the HFP content. This difference in phase transition behavior between ET-C4F9 and ET-CF3 copolymers is reasonably interpreted as follows: the short side groups (-CF3) of HFP monomeric unit are included in the crystal lattice of E/TFE chains and the unit cell is expanded gradually with an increment of the HFP content, resulting in the decrease in phase transition point because of easier thermal motion of the chains. On the other hand, the long side groups [-(CF2)3CF3] of NFH monomeric units are excluded out of the crystal lattice and located on the lamellar surfaces or in the amorphous region and do not affect very much the phase transition temperature even when the NFH content is increased. In association with such a change in crystal structure, the long period of stacked lamellar structure was found to decrease remarkably in the case of NFH, whereas it does not change very much for HFP, consistent with the interpretation of the above-mentioned WAXD data.  相似文献   
64.
Watching and tracking an object while seeing a much wider view is one of advantages of the eye system. We proposed and developed a tracking camera system that mimics the eyes by using double-lens modules. In the system, a wide view is captured through the wide-lens module, while the target in it is tracked and magnified through the telescopic lens module. Electronic circuits for tracking control are implemented onto the reconfigurable VLSI or FPGA in order to embed the parallelism in the tracking algorithm into the hardware. A successfully developed FPGA-based prototype performs high-speed tracking at the video-rate. This work was present in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27, 2007  相似文献   
65.
66.
The effect of largest follicle aspiration or hCG administration before induction of superovulation on the ovarian response of Japanese Black beef cows was investigated using a crossover design in which induction of superovulation was attempted in every cow. The superovulatory response of cows whose largest follicle had been aspirated from the ovaries by ultrasound-guided follicular aspiration 1 day before induction of superovulation, did not differ from the response in non-treated control cows. In contrast, in cows given 5,000 IU of hCG 3 days before induction of superovulation, the proportions of fertilized ova and transferable embryos significantly decreased compared with the other groups.  相似文献   
67.
After an i.p. transplantation of an allogeneic tumor (Meth A) to C57BL/6 mice, a macrophage (M phi)-rich, non-T, non-NK cell population is induced as the major infiltrate and cytotoxic cells. We here evaluated the role of the M phi s in the rejection of allografted Meth A cells and characterized the M phi s in comparison with other well-known M phi s. At all time intervals after transplantation, the highest cytotoxic activities against Meth A tumor were obtained with the M phi-rich population. In addition, the lymphocyte-rich population had a significant but low cytotoxic activity, whereas two other population types, granulocytes and large granular cells, were inactive. When the M phi-rich or the T cell-depleted M phi-rich population was i.p. transplanted simultaneously with Meth A cells into untreated C57BL/6 mice, the tumor cells were rejected without growth. After specific elimination of M phi s by in vivo application of dichloromethylene diphosphonate-containing liposomes, the cytotoxic activity against Meth A cells was hardly induced at the transplantation site of Meth A cells and the allografted Meth A tumor continued to grow, indicating that a type of M phi is the effector cell essential for the rejection. In contrast to other well-known M phi s, the cytotoxic activity against Meth A cells was cell-to-cell contact dependent and soluble factor (e.g., NO and TNF-alpha) independent. Moreover, the cytotoxic activity of the M phi s (H-2b) against 51Cr-labeled Meth A (H-2d) cells was inhibited by the addition of unlabeled H-2d, but not H-2b, H-2k or H-2h, lymphoblasts as well as Meth A cells, implying the specific interaction of the M phi s with H-2d cells.  相似文献   
68.
A lattice model has been developed to explore impact damage patterns in brittle materials. The damage evolution was modelled as a process involving the change of strain-energy distribution by cracking. Using a cubic lattice system, a large strain energy was supplied to the system surface. Crack growth initiated by this local energy supply was followed by means of computer simulations. The damage patterns were compared for systems which have different distributions of strain energy stored prior to the local energy supply. The simulations reveal a characteristic difference in the damage pattern. Impact damage for a system with a spatially fluctuating distribution of strain energy is limited around an impact point. Impact damage for a systen with a relatively uniform distribution of strain energy penetrates deeply. The results of the simulations are discussed in connection with the material evaluation and the material resistance.  相似文献   
69.
70.
We report the results of transfer of the long toe flexors and lengthening of the calcaneal tendon in 33 patients with equinovarus deformity requiring orthoses after a stroke. Review of 29 patients more than two years after surgery showed that 21 were able to walk without an orthosis. Equinovarus deformity had recurred in six patients and hammer toe in 11, but walking ability without bracing was still better in seven of these. Results are improved by the release of the short toe flexors.  相似文献   
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