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71.
72.
AK Tan 《Canadian Metallurgical Quarterly》1998,39(9):403-405
AIM OF STUDY: This study was done to examine the usefulness of botulinum toxin A injections in treating various neurological disorders such as hemifacial spasm, blepharospasm, focal dystonia and task-specific dystonia. METHODS: This was a prospective, open-labelled trial of patients seen in a Movement Disorders Clinic with dyskinesias potentially treatable with botulinum toxin. All patients were assessed before and after injections using clinical rating scales, and those with focal and task-specific dystonias were also recorded on videotape. RESULTS: There were 102 patients with hemifacial spasm, 3 with blepharospasm, 13 with neck dystonia, 6 with writer's cramp, I with musician's cramp, and I with jaw dystonia. All patients with hemifacial spasm and blepharospasm obtained good results, while 77% of those with cervical dystonia received substantial benefit. Only half of those with writer's cramp improved. Hemifacial spasm seems more prevalent in Singapore compared with Western populations. CONCLUSION: Injections of botulinum toxin are useful in treating the various neurological disorders studied. This is an advancement in the treatment of these dyskinesias which respond poorly to oral medications. 相似文献
73.
A new colour quantisation and quadtree based image compression scheme is proposed. The features of the new scheme are that colour palette ordering and requantisation of the decoded image for palette-based monitor displays are not required. Thus, fast decoding and displaying can be achieved 相似文献
74.
Y. Liu W. Zhu O. K. Tan X. Yao Y. Shen 《Journal of Materials Science: Materials in Electronics》1996,7(4):279-282
A low-temperature plasma-enhanced chemical vapour deposition (PECVD) technique has been employed to produce ultrafine tin oxide powders. The structural features and phase transition of this material have been characterized using differential thermal analysis (DTA), thermogravimetric analysis (TGA), X-ray diffraction, infrared spectroscopy (IR) and transmission electron microscopy (TEM). The oxygen absorption behaviour and gassensing properties have been investigated by electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS) and electrical measurements. Thick film gas sensors made from such ultrafine SnO2 powders yield better sensitivities than those of normal undoped SnO2 gas sensors. A gas-sensing reaction mechanism is also proposed. 相似文献
75.
76.
The human chromosome 9 displays the highest degree of structural variability. Four different types of variants are described including pericentric inversion, extra G-positive band in the q arm, additional G-positive band in the p arm and duplication of band 9q21-q22. It is important to demonstrate inheritance from a phenotypically normal individual in order to differentiate between a variant chromosome and an abnormal chromosome. 相似文献
77.
Cytological identification of soybean mitotic metaphase chromosomes (2n = 40) has been severely limited by their small size and uniform karyomorphology. We have developed fluorescent in situ hybridization (FISH), PCR-primed in situ labelling (PCR-PRINS) procedures, and molecular probes for routine cytological identification and for the physical mapping of soybean somatic chromosomes. Chromosome preparation has been achieved by modifications of previous protocols and through the preparation of root-tip protoplasts prior to chromosome spreading. Initially our probe selection focused on highly repeated DNAs that provide very intense localized hybridization signals. Repetitive gene probes that have proven valuable include the rDNA loci (5S and 45S) which are chromosome specific. We have also developed satellite DNA probes for two different sequence families: the SB92 and the STR120 satellites. Both of these are tandemly arranged at multiple chromosomal loci. By using different cloned examples of each family, we have been able to selectively label unique subsets of soybean chromosomes. Double hybridization with biotin and digoxigenin labeled probes has allowed us to determine the chromosomal overlap between different probes. In addition, we have joined portions of the metaphase chromosome painting patterns with the genetic map by single-copy FISH and PCR-PRINS detection of the RFLP loci G8.15, G17.3, and A199a and A199b. Total genomic DNA in situ hybridization (GISH) patterns were also used to characterize the soybean chromosomes. 相似文献
78.
Compressive and tribological properties of Al2O3 fibre and hexagonal BN particle hybrid reinforced Al-Si alloys 总被引:6,自引:0,他引:6
Al2O3 fibre-hexagonal BN particle hybrid reinforced aluminium-silicon alloys were fabricated by centrifugal force infiltration route. Hardness test and ultimate compressive test results are reported. The wear and friction properties of hybrid MMCs was investigated by means of a block-on-ring (bearing steel) type wear rig in a dry sliding condition. It is shown that the hardness and ultimate compressive strength of hybrid MMCs was evidently decreased with the addition of hexagonal BN particles, however, the wear rate and coefficient of friction of hybrid MMCs was improved simultaneously with increase of BN particle volume fraction, especially for the higher applied loads in the test. 相似文献
79.
80.
Efficient encoding of IEEE 802.11n LDPC codes 总被引:1,自引:0,他引:1
Addressed is the issue of LDPC coding for the emerging IEEE 802.11n standard. An efficient encoding algorithm is proposed. The algorithm is simple and easy to implement. The memory requirement is trivial 相似文献