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21.
A. I. Tew 《Medical & biological engineering & computing》1988,26(1):68-74
For some disabled people pointing provides a more convenient means of communication and control than the use of switches.
The quadriplegic who retains good control of head movement can be provided with a number of input alternatives, but no existing
system meets all the requirements of a general-purpose electronic pointing device. Consequently the Oxford Optical Pointer
has been developed. The principle by which it converts relative direction into analogue electrical signals is described and
its application as a head-mounted device for controlling an electric wheelchair is presented. 相似文献
22.
F. X. Jiang P. Temple-Smith N. G. Wreford 《Anatomical record (Hoboken, N.J. : 2007)》1994,238(2):191-198
Postnatal development and differentiation of the rat epididymis was studied in the rat from 15 to 120 days of life using stereological techniques. Both the relative volume (volume density) and absolute volume of the epithelial, interstitial, and luminal compartments in the initial segment, caput, corpus, and cauda epididymides were determined. In all segments the volume density of the epithelial compartment increased between days 15 and 30 before falling to adult values at 45 days in the initial segment (0.476 ± 0.031), at 60 days in the caput (0.258 ± 0.028) and at 90 days in the corpus (0.245 ± 0.007) and cauda (0.140 ± 0.004). The relative volume of the interstitium decreased, whilst that of the lumen increased over the same period with adult values being achieved earlier in the proximal segments than in the distal segments. In contrast to volume fraction the absolute volume of all compartments in all segments increased from day 15 to day 90. Between 90 and 120 days the absolute volumes of compartments in the initial segment and caput showed little volume change. All compartments in the corpus and cauda showed significant increases in volume over the same period. A similar pattern of development was observed with respect to the surface area of both the luminal and basement membrane aspects of the epithelium; surface area per unit volume (surface density) in all segments reached adult values at approximately 60 days, whilst the increase in absolute area of the surfaces ceased at 90 days in the initial segment and caput and continued to 120 days in the corpus and cauda. The total length of the epididymal tubule showed the same pattern with no increase in length apparent in the initial segment and caput after 90 days. Length however continued to increase in the corpus and cauda between 90 and 120 days. Tubule and luminal diameter reached their definitive values in the initial segment on day 60 but continued to increase until day 90 in the distal segments. Epithelial height increased between 15 and 30 days in all segments; in the caput, epithelial height was greatest on day 30 before decreasing slightly; and in the corpus and cauda maximal epithelial height was observed on day 45 decreasing to stable values on day 60 and 90, respectively. All the data is consistent with a proximal to distal differentiation and development of the epididymis with growth continuing in all segments after the establishment of the definitive architecture. Growth of the distal segments continued after its cessation in the proximal segments. © 1994 Wiley-Liss, Inc. 相似文献
23.
示范区创建活动与社区卫生服务长效机制的建立和可持续发展对策的思考 总被引:1,自引:1,他引:0
通过第三方评估全国社区卫生服务示范区是我国社区卫生服务发展史上的一大创举。此项活动的开展,极大的提高了各地政府对发展社区卫生服务的思想认识、政策理解和经费投入力度。通过创建和评估活动,系统总结了各申报地区社区卫生服务的经验和特色,分析了存在的问题和不足,提出了发展社区卫生服务的对策和建议,制定了社区卫生服务可持续发展的长效机制,取得了预期效果,达到了预期目的。随着《国务院关于发展城市社区卫生服务的指导意见》的出台,示范区的典型示范效应会日益凸显出来,对我国社区卫生服务的发展将起到不可估量的作用。 相似文献
24.
目的用易获得的化学药物建立大鼠四肢畸形发生率稳定、畸形类型特异的动物模型。方法采用抗肿瘤类致畸药物白消安作为受试物,观察不同剂量和不同给药时间的胎仔畸形率、畸形类型及特征。结果在大鼠受孕第12天(GD12),一次经口给予白消安25mg/kg时,胎仔畸形类型主要为肢体畸形。肢体畸形率以活胎计为37.9%(33/87),以窝计为61.5%(8/13)。畸形类型常见于多指(趾)和缺指(趾),掌跖骨缺失和骨化不全发生率也较高。此外,还发生胫骨缺失和骨化不全,在观察大体形态时所见的短肢是由胫腓骨缺失和发育不全所致。四肢畸形的发生率和严重程度存在着不对称性,后肢较前肢出现率高,缺指(趾)畸形较其他畸形出现率高。结论成功建立大鼠肢体畸形动物模型,为进一步分析研究肢体发育畸形的分子机制和潜在原因奠定了基础。 相似文献
25.
目的:评价一期后、前路手术治疗发育性颈椎管狭窄合并巨大椎间盘突出的特点及疗效。方法:回顾分析2002年2月至2006年1月接受该术式的21例患者的临床资料,对手术前后临床表现、JOA评分、MRI影像变化以及术后神经功能改善率及并发症进行总结分析。结果:术后未发生神经系统症状加重、感染及内固定失效等并发症。获得1年以上随访者21例,平均随访时间为29.2个月,术后3个月、12个月时神经功能改善率分别为:58%、66%;16例获得2年以上随访者神经功能改善率为71%。结论:一期后、前路手术治疗发育性颈椎管狭窄合并巨大椎间盘突出可缩短治疗周期,相对节省治疗费用,同时解除了硬膜囊前、后方的压迫,减压彻底,疗效满意。 相似文献
26.
Niina S. Jalava Francisco R. Lopez-Picon Tiina-Kaisa Kukko-Lukjanov Irma E. Holopainen 《International journal of developmental neuroscience》2007,25(2):121-131
In this study, we analyzed the spatiotemporal expression patterns of the high-molecular weight (MAP2a and b) and low-molecular weight (MAP2c and d) cytoskeletal microtubule-associated protein-2 (MAP2) isoforms with Western blotting, and the cellular localization of the high-molecular weight MAP2 isoforms with immunocytochemistry in the hippocampi of 1- to 21-day-old rats. Moreover, the temporal profile (from 30 min to 1 week) of MAP2 isoform reactivity to kainic acid-induced status epilepticus was studied in P9 rats. During development, the expression of the high-molecular weight MAP2 isoforms significantly increased, while the low-molecular weight isoforms decreased, the most prominent changes occurring during the second postnatal week. This developmental increase in the high-molecular weight MAP2 expression was also confirmed with immunocytochemistry, which showed increased immunoreactivity, particularly in the molecular layers of the dentate gyrus, and in CA1 and CA3 stratum radiatum. In 9-day-old rats, status epilepticus resulted in a rapid transient increase (about 210%) in the high-molecular weight MAP2 expression, without any effect on the low-molecular weight MAP2. Moreover, disturbed dendritic structure in the CA1 and CA3 stratum radiatum was manifested as formation of varicosities 3h after the kainic acid treatment. The strictly developmentally regulated MAP2 isoform expression suggests different functional roles for these proteins during the postnatal development in the rat hippocampus. Moreover, high-molecular weight MAP2s may play a role in nerve cell survival during cell stress. 相似文献
27.
我国环卫设备的现状与发展趋势——环卫设备的标准化、系列化 总被引:1,自引:0,他引:1
介绍了我国环卫设备的发展现状,并提出了存在的一些问题.根据我国环卫产业政策的有关要求:论述了各种环卫设备研究和开发的方向,指出大力推进环卫机械设备的标准化、系列化、通用化、规模化是社会主义市场经济发展和环卫业发展的需要. 相似文献
28.
A. J. Bullock R. A. Duquette N. Buttell S. Wray 《Pflügers Archiv : European journal of physiology》1998,435(4):575-577
Intracellular pH (pHi) is known to modulate contraction. Neonatal tissues can differ from adult tissue in contractile response to stimuli known
to alter pHi e.g. hypoxia. Changes of pH are attenuated by buffering, thus any difference in buffering power (β) between tissues could
affect their functional response to pHi perturbation. Similarly the extent to which any extracellular pH (pHo) alteration is transmitted into a pHi change will also influence function. We have therefore determined the intrinsic β and effect of pHo change on pHi in neonatal and adult ureteric, uterine and gastric smooth muscles using the pH-sensitive fluorophore carboxy-SNARF. β was
found to be similar in the three adult tissues, but there were significant differences between neonatal tissues. In contrast,
we found little difference in the amount of pHi change produced by pHo change between neonatal and adult tissues from the same smooth muscle, but a difference between smooth muscles. These data
highlight significant differences between smooth muscles and their developmental state, which may contribute to different
degrees of protection when pH is perturbed.
Received: 17 October 1997 / Received after revision: 27 November 1997 / Accepted: 28 November 1997 相似文献
29.
Renal adaptation to changes in inorganic sulfate intake and age was studied by comparing sulfate uptake by proximal tubule
brush border membrane vesicles (BBMV) from guinea pigs of different ages on relatively high- or low-sulfate diets. Adult (>60
days) or young guinea pigs (<25 days) were fed either a control diet (0.28% sulfur content), a sulfur-free diet, or a high-sulfate
diet. After 5 days on the diet, BBMV were obtained and kinetic analysis of 35sulfate uptake was determined. In adult guinea pigs, the low-sulfate diet produced a significant increase in apparent maximal
velocity (V
max). In young guinea pigs, a lower sulfate intake did not appreciably increase V
max, but a high-sulfate intake produced a reduction in V
max. The affinity for sulfate (K
m) was not changed in either age group. The dietary sulfate intake did not alter sodium gradient dependent-D-glucose or 32phosphate V
max. In conclusion, our data indicate that renal inorganic sulfate BBMV uptake is regulated and responds to conditions of increased
need (i.e., during the growth phase in young animals and during periods of decreased sulfate availability in adult animals)
by increasing BBMV V
max.
Received September 9, 1994; received in revised form March 18, 1997; accepted March 20, 1997 相似文献
30.
Benjamin Sadlack Ralf Kühn Hubert Schorle Klaus Rajewsky Werner Müller Ivan Horak 《European journal of immunology》1994,24(1):281-284
Interleukin (IL)-2 and IL-4 are considered as important regulators of growth and differentiation of lymphocytes. We report that in mice made deficient for both IL-2 and IL-4 by gene targeting all major T cell subsets and B cells were normal, indicating that IL-2 and IL-4 are not essential for development of the immune system. Paradoxically, proliferation of T cells was increased in both IL-2- and IL-4-deficient homozygous mice. 相似文献