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31.
Toshio Mizutani Ken-ichi Nakamura Mutsuo Enomoto Masuhiro Sakata Shigeo Yamada 《Neuropathology》1998,18(1):80-90
A neuropathological study on 1540 consecutive autopsy brains ranging from 60 to 107 years of age revealed the following points. (1) Of the of the demented cases of the plaque-predominant type, 93% were complicated with multiple tiny cortical infarcts. They showed a tendency for dementia to develop before or after the appearance or worsening of a systemic disorder such as cardiovascular disease, respiratory infection and cancer. However, there was no case showing Alzheimer-type dementia (ATD). (2) The plaque-predominant type might be an extreme condition of brain aging in terms of senile plaques (SP). It is likely that although the pathological appearance of SP alone is not responsible for dementia, its coexistence with multiple cortical infarcts could be the cause of dementia. Therefore, this type should be distinguished from ATD. (3) Primary hippocampal degeneration could also be an extreme condition of brain aging in terms of neurofibrillary tangles. This condition was different pathologically from the hippocampal lesion in ATD. (4) Several characteristics of old-old and oldest-old patients were clarified. 相似文献
32.
K. D. Blake S. Madden B. W. Taylor L. Rees 《Pediatric nephrology (Berlin, Germany)》1996,10(6):693-695
.A sedation regimen using sequential oral trinepazine, intravenous Pethco (pethidine, chlorpromazine and promethazine) and
diazemuls was evaluated in children having native kidney (n = 17) and transplant kidney (n = 17) biopsies. Biopsy was successful in all cases, with no serious side effects. A self-reported scale of memory recall
and pain perception showed the optimal time for biopsy to be between 30 and 90 min after the intravenous Pethco. The child’s
level of distress was measured by a self-reported scale, a parent-reported scale and an observational scale for doctors and
nurses; 45% of children rated themselves highly distressed prior to the procedure, their parents being the best assessors
of this distress. Younger children and those undergoing native kidney biopsy had less understanding of the procedure. Children’s
worries could be clearly categorised into procedural and outcome issues: those undergoing transplant biopsy were more worried
about outcome, whereas those undergoing native kidney biopsy were more worried about the procedure.
Received April 3, 1995; received in revised form and accepted April 17, 1996 相似文献
33.
近年来由于生活压力的增加,我国越来越多的育龄期男女罹患高血压,因此如何规范管理备孕期高血压已成为当前的焦点。本文从备孕期间血压的监测与评估和降压药的使用两方面分别对育龄期男性和女性备孕期间的血压规范管理进行阐述,强调女性备孕期间的高血压管理应同时考虑母体和胎儿的安全性,选择相对安全的降压药,如甲基多巴、拉贝洛尔、硝苯地平等;男性备孕期间的高血压管理应同时考虑降压药的疗效及其对性功能和精子的影响,推荐奈必洛尔、血管紧张素转换酶抑制剂(ACEI)/血管紧张素Ⅱ受体拮抗剂(ARB)和钙离子通道阻滞剂(CCB)类药物,旨在为临床备孕期高血压的管理提供指导并为未来研究提供参考方向。 相似文献
34.
The Modality Specificity of the Slow Negative Wave 总被引:1,自引:0,他引:1
Event-related potentials were recorded in a simple reaction time task using a 3-sec interval between S1 and S2. The sensory modalities of S1 and S2 were varied across 4 conditions to yield all possible combinations of tones and flashes. A negative component which peaked between 600 and 800 msec after S1 was specific in scalp distribution to the modality of S1 but not S2. It was concluded that this negative component is a response to S1 and not related to processes associated with anticipation of S2. A slow negative shift which peaked at S2 was largest at the vertex in all conditions, suggesting its motor origin. A trend for the latter activity to be more negative in posterior recordings when S2 was visual than auditory leaves open the possibility that the terminal CNV is a combination of motor activities and anticipation of the sensory modality of S2. 相似文献
35.
住房类型、环境与居民健康协作研究之四——住房类型、环境与第二代成人健康 总被引:1,自引:0,他引:1
本文报告了北京市西城区三种类型住房三代同堂家庭调查样本125户中第二代成人199人的问卷调查结果。调查结果显示三种类型住房第二代成人的健康状况及烟酒嗜好差别无显著性;楼房的居住环境优于平房,但邻里交往不如平房密切;对居住条件和生活的自我评价主要取决于住房设施,邻里关系、年龄和性别,而受住房类型影响较小。 相似文献
36.
F. Schenk B. Contant P. Werffeli 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1990,82(3):641-650
Summary Age-related cognitive impairments were studied in rats kept in semi-enriched conditions during their whole life, and tested during ontogeny and adult life in various classical spatial tasks. In addition, the effect of intrahippocampal grafts of fetal septal-diagonal band tissue, rich in cholinergic neurons, was studied in some of these subjects. The rats received bilateral cell suspensions when aged 23–24 months. Starting 4 weeks after grafting, they were trained during 5 weeks in an 8-arm maze made of connected plexiglass tunnels. No age-related impairment was detected during the first eight trials, when the maze shape was that of a classical radial maze in which the rats had already been trained when young. The older rats were impaired when the task was made more difficult by rendering two arms parallel to each other. They developed an important neglect of one of the parallel tunnels resulting in a high amount of errors before completion of the task. In addition, the old rats developed a systematic response pattern of visits to adjacent arms in a sequence, which was not observed in the younger subjects. None of these behaviours were observed in the old rats with a septal transplant. Sixteen weeks after grafting, another experiment was conducted in a homing hole board task. Rats were allowed to escape from a large circular arena through one hole out of many, and to reach home via a flexible tube under the table. The escape hole was at a fixed position according to distant room cues, and olfactory cues were made irrelevant by rotating the table between the trials. An additional cue was placed on the escape position. No age-related difference in escape was observed during training. During a probe trial with no hole connected and no proximal cue present, the old untreated rats were less clearly focussed on the training sector than were either the younger or the grafted old subjects. Taken together, these experiments indicate that enriched housing conditions and spatial training during adult life do not protect against all age-related deterioration in spatial ability. However, it might be that the considerable improvement observed in the grafted subjects results from an interaction between the graft treatment and the housing conditions. 相似文献
37.
探索了磷酸四钙(Ca4(PO4)2O,TTCP)的制备,并合成了磷酸钙骨水泥(CPC),对CPC固化时间、引起浸泡液pH值的变化、抗压强度、产物物相组成及微观结构进行了研究。结果表明:在真空条件下、1500℃下煅烧6h可制得TTCP,并含有少量CaO。CPC初凝时间为4min、终凝时间为15min,浸泡1d和7d后的抗压强度分别为20MPa和35MPa,浸泡液的pH值在6.4~8.9之间变化,这些性能均符合临床用CPC的性能要求。CPC水化产物为片状或针状羟基磷灰石(Ca5(PO4)3OH,HA),相互交错呈连续分布的网状结构,这种结构有利于材料强度的提高。实验研制的CPC材料可用于骨缺损的修复治疗。 相似文献
38.
梯度降温、深低温保存同种骨组织生物力学特性研究 总被引:5,自引:0,他引:5
目的 研究梯度降温、深低温保存同种骨组织的生物力学特性 ,为临床应用理想的同种骨移植材料修复各种原因引起的骨缺损提供理论依据。方法 将新鲜尸体的股骨经过预处理后 ,梯度降温 (- 2℃ /min)至 - 6 0℃ ,投入 - 80℃深低温冰箱中保存。一月后取出 ,进行生物力学实验。结果 实验得出的数据与以往研究新鲜骨的数据十分接近。结论 梯度降温、深低温保存的同种骨保持与新鲜骨最为接近的生物力学特性 ,实验得出的数据也将为以后的进一步研究提供依据 相似文献
39.
Aoyama K Ozaki Y Nakanishi T Ogasawara MS Ikuta K Aoki K Blomgren K Suzumori K 《American journal of reproductive immunology (New York, N.Y. : 1989)》2004,52(6):362-369
PROBLEM: The distribution and activation of mu-calpain and possible cleavage of integrin in human endometrial cells under hypoxic condition were investigated. METHOD OF STUDY: Human endometrial epithelial and stromal cells were subjected to hypoxia, and subsequently used for immunostaining and western blot analysis. RESULTS: The proform of mu-calpain was detected in the cytoplasm of normal cells, and displayed a substantial decrease after hypoxia. Conversely, the active form of mu-calpain was not detected in normal cells, but was abundant after hypoxia. The cytoplasmic domain of integrin beta3 was also detected in the cytoplasm of endometrial cells. Western blot analysis confirmed that both the proform of mu-calpain and the integrin beta3 cytoplasmic domain decreased during hypoxia. CONCLUSIONS: Mu-calpain is activated in human endometrial cells during hypoxia and that subsequent cleavage of the integrin beta3 cytoplasmic domain may give some adverse effects to the function of human endometrium. 相似文献
40.
We examined the effects of early rearing experience on the development of dominance status in 53 juvenile (age 3) and then in 38 adult (ages 5-8) rhesus macaques. Based on previous research investigating the behavioral outcomes of nursery-rearing, we predicted that mother-reared (MR) monkeys would outrank peer-only reared (PR) monkeys, which would in turn outrank surrogate/peer-reared (SPR) subjects. Juvenile MR and PR subjects did not differ in ranks, but monkeys from both rearing backgrounds outranked SPR cage-mates at age 3. Independent of rearing condition, high-ranking juveniles gained the most weight between ages 1-3, suggesting that low status may be associated with decreases in early weight gain. Adult MR subjects outranked both PR and SPR subjects, with PR animals occupying intermediate ranks. These results indicate that impoverished early experiences, such as adult absence and limited social interaction, are useful predictors of future social success in rhesus macaques. 相似文献