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1.
One high potency (HP) and two low potency (LP) commercial whole short ragweed (WSR) extracts were assayed for relative potency (RP) by antigen E (AgE-Amb a 1), RAST inhibition, and parallel line bioassay (PLBA). The RP of the HP extract (300 micrograms AgE) was equal to the reference WSR, but the LP extracts were only approximately 0.01 of the RP of the reference. Each extract was administered to fall hay fever patients with skin sensitivity to WSR (less than or equal to 10(-3) micrograms/ml AgE for sum of erythema = 50 mm) to the maximum tolerated dose, or 0.5 cc of the concentrate, by either a 9- or 40-dose regimen. HP-treated patients had significantly lower symptom scores than untreated controls. No significant difference was noted in the total symptom scores between HP and LP extract-treated patients. Despite approximately 100-fold differences in the RP of HP versus LP extracts, both produced similar frequencies of severe systemic and severe late phase local reactions. Furthermore, when RP of HP and LP extracts were estimated by PLBA, both reached similar peak dosages, similar dosage for IgG WSR antibody response, and comparable IgG WSR antibody levels, indicating that the WSR dose estimates based on RP were bioequivalent. The 9-dose HP regimen produced fewer late phase local and systemic reactions per patient than the 40-dose HP regimen. Most patients experiencing severe systemic reactions were among those most skin sensitive to WSR. The number of systemic reactions per injection was significantly higher at higher WSR doses. One LP extract produced a high incidence of systemic reactions in the initial three injections. With respect to HP, its RP varied approximately 10-fold depending on the skin sensitivity of the patient to heat-stable ragweed allergens, demonstrating that it was compositionally different. However, when the dose of this extract was estimated by RP based on the skin sensitivity of each patient, the peak dose of the extract as well as the doses associated with late phase and systemic reactions were found to be similar to the HP doses. This indicated that immunizing dose estimates of compositionally different WSR extracts based on RP by PLBA were also bioequivalent.  相似文献
2.
住院精神病患者跌倒特点分析   总被引:3,自引:0,他引:3  
目的了解精神病患者发生跌倒的特点,为减少精神病患者发生跌倒提供依据。方法对2002年1月1日-2007年6月31日在我院住院治疗期间发生跌倒的患者,以查阅病历、访谈和实地观察跌倒环境获取资料进行回顾性分析。结果117名患者共发生跌倒139人次,男77人次,女62人次。发生跌倒患者平均年龄57.5岁,其中≥60岁者66人次,占47.5%。跌倒在日间发生73次,占52.5%,夜间66次,占47.5%。跌倒地点以洗漱室38人次(27.3%),普通病室29人次(20.9%),饭厅28人次(20.1%)最多见。跌倒的形式以行走时不慎滑倒42人次(30.2%),体位改变时跌倒26人次(18.71%)常见。跌倒后致外伤81人次(58.27%),骨折53人次(38.13%),外伤合并骨折2人次(1.44%),其它3人次(2.16%)。结论精神科老年患者容易跌倒,易致外伤及骨折。  相似文献
3.
The allocation of attention during locomotion is altered by anxiety   总被引:1,自引:1,他引:0  
We tested the hypotheses that: (1) anxiety regarding the possibility of falling alters the attentional demands of gait; and (2) this alteration in the attentional requirements of gait occurs independently of gait pattern accommodations. Sixteen younger and 15 older adults participated in this study. Subjects walked at a self-determined velocity along a 7.2-m walkway under four conditions of postural threat; the walking conditions varied depending on the width constraints of the walkway (60 cm vs 15 cm) and the height of the walking surface (0 cm vs 60 cm). Attentional demands of locomotion in each condition of testing were assessed using the dual-task methodology, in which participants verbally responded to an auditory cue as quickly as possible while continuing to walk. Our findings revealed that: (1) participants were successful in verbally responding to the auditory cue without modifying their gait pattern; (2) reaction times increased for all subjects when walking in the condition of greatest postural threat; (3) the attentional demands for locomotion varied with the phase of the gait cycle for younger adults but not for older adults; (4) the phase-dependent effect for younger adults disappeared in the condition of greatest postural threat, while reaction time scores for older adults systematically increased; and (5) increases in reaction time persisted despite significant changes in gait kinematics. Our findings confirm that anxiety increases the attentional demands for locomotion and provide further explanation for age-dependent increases in the attentional demands of gait. Furthermore, our findings confirm that fall-related anxiety predicates an increase in the allocation of attention to locomotor control that is independent of gait pattern adjustments. Electronic Publication  相似文献
4.
跌倒检测系统的研究进展   总被引:1,自引:0,他引:1  
目的:随着社会老龄化的迅速发展,针对老年人群的健康安全监护的需求日益增加。跌倒检测系统能够有效检测老年人跌倒事件的发生并及时报警,保护老年人的健康及安全。方法:对一些常见的跌倒检测的系统、算法、设备及其应用进行了比较研究,并提出了一些关于系统评价标准设定的建议。结果:本文将跌倒检测系统分为基于视频图像的跌倒检测系统、可穿戴式的跌倒检测系统和环境式的跌倒检测系统三大类,并从舒适性、实用性、准确率等方面进行比较,还从实验对象选择、实验环境设置、样本动作分类和检测指标确立四个方面对建立跌倒检测系统的评价标准进行了阐述。结论:本文进行的比较研究系统地概述了跌倒检测系统的常见技术和算法,提出了其评价标准的基础框架,对于其进一步的研究设计、商品化开发具有一定指导意义。  相似文献
5.
一种老年人移动健康监护系统的研究   总被引:1,自引:0,他引:1  
目的:设计一种老年人移动监护系统,实现移动心率检测,跌倒检测,紧急情况自动电话呼叫与GPS定位,减少突发事件对老年人的健康威胁。方法:采用分层的体系结构,第一层为传感器层,用于采集并实时分析ECG信号以及加速度数据,第二层为手持终端,用于汇集各传感器数据,综合判断并实现数据远程传输、呼叫以及定位,第三层位于远程服务器,实现数据库管理,数据显示等。结果:分层的体系结构有利于系统功能的扩展,有利于传感器单元的可穿戴性。结论:基于无线传感器网络与GPRS网络的移动健康监护系统能够有效实时地对老年人的健康与安全状况进行监护,对老年人生命安全保障具有重要意义。  相似文献
6.
目的:比较人抗菌肽FALL-39及其突变肽对细菌脂多糖(lipopolysaccharides,LPS)介导的诱生型一氧化氮(nitric oxide, NO)产生的影响。方法:体外常规培养人单核吞噬细胞THP-1,LPS刺激细胞,分别用人抗菌肽FALL-39以及突变肽FALL-39-Lys24,FALL-39-Lys32,FALL-39-Lys24′32处理细胞。应用RT-PCR方法测定LPS诱生型一氧化氮合酶(induced nitric oxide synthase,iNOS) 以及FALL-39 mRNA的表达,用硝酸还原酶法测定细胞培养上清液中NO的含量。小鼠腹腔注射更生霉素和LPS建立内毒素血症模型,分别用抗菌肽处理动物,取?舛ㄑ逯蠳O的含量。结果:LPS刺激FALL-39 mRNA的表达增加;同时也诱导NO mRNA的表达以及细胞培养上清液中NO含量的增加。人抗菌肽FALL-39及其突变肽FALL-39-Lys24,FALL-39-Lys32,FALL-39-Lys24′32可以抑制LPS诱导的NO的产生;其中FALL-39-Lys24′32的抑制作用最为明显。结论:抗菌肽FALL-39及其突变肽具有抗内毒素作用,其机制与抑制LPS诱导的NO产生有关。  相似文献
7.
Decreased steadiness of muscle force may be associated with ageing and could be a cause of falls in older people. We studied this in isometric and anisometric quadriceps contractions in healthy young and older people. The older group contained people with and without a history of medically unexplained falls. Forty-four young (aged 18–40 years) and 78 older (aged > 70 years) subjects participated. In the latter group 34 people had a history of falling (fallers) and 44 did not (non-fallers). Isometric steadiness was measured by the coefficient of variation (CoV) of force at 10, 25 and 50% maximal voluntary force (MVC). Anisometric steadiness was measured by the SD of acceleration during concentric and eccentric contractions against two external loads (1 and 5 kg). There was an overall trend for the younger subjects to be most steady and the fallers the least but the differences were not consistently significant. Isometric steadiness was unaffected by force in all groups. The fallers were less steady (P < 0.001) than both the young and non-fallers, who had similar values. During anisometric contractions, steadiness was similar with both external loads and types of contraction in all groups. During dynamic contractions the older subjects were less steady (P < 0.002). Only eccentric contractions distinguished between the two older groups, with the fallers being less steady by 31% (P = 0.013). These data indicate ageing per se is associated with decreased anisometric, but not isometric, steadiness. Greater unsteadiness during eccentric contractions in the fallers could be an important mechanism of medically unexplained falls.  相似文献
8.
Summary The electromyographic (EMG) responses from soleus and tibialis anterior muscles and the monosynaptic H- and T-reflex responses from soleus muscles were recorded bilaterally from conscious baboon while unexpectedly dropping it with unrestricted vision. These responses were recorded either after unilateral vestibular neurectomy (U.N. baboons) or after bilateral neurectomy performed in one stage (B.N. 1 baboons) and in two stages (B.N. 2 baboons).A positive correlation was found between modifications and development of EMG responses and reflex data. In the U.N. baboons, some differences were observed when comparing data from the H- and T-reflex methods, suggesting that recovery of normal responses to fall is achieved both by means of direct influences on -motoneurons and via the -loop.In the U.N. baboons postural reactions to fall developed in three distinct periods. The first or critical stage showed asymmetrical EMG and reflex responses with increased responses from contralateral soleus muscle and decreased responses from ipsilateral soleus. Opposite effects were recorded from tibialis anterior flexor muscles. The second or acute stage which began around 4 to 7 days after surgery exhibited symmetrical, but very reduced, responses when compared to the control in soleus muscles, and symmetrical, but increased, responses from tibialis anterior muscles. This stage lasted until about the end of the second postoperative week and was followed by the third or compensatory stage during which EMG as well as reflex responses developed towards the control pattern in all tested muscles. Almost normal responses were recorded on both sides 3 weeks after surgery.Only a partial recovery was found in the B.N. 1 baboons, indicating that the contralateral remaining labyrinthine afferences constitute a necessary condition for the full compensation of postural reactions to fall in the case of unilateral vestibular neurectomy. The Bechterew's compensation was obtained in the B.N. 2 baboons.These results are discussed in relation with the general organization of the vestibulospinal pathways and with those concerning development of the postoperative activity at the vestibular nuclei level. A model of vestibular compensation achieved by means of a multisensory substitution process is suggested.Preliminary results have been presented at the IVth International Symposium of Posturography (Sofia, 1977)  相似文献
9.
Summary In a previous study the muscle responses from the lower limbs were studied in the Baboon (Papio-Papio) during sudden falls. On the other hand, recent findings concerning the role of vision in the control of posture during rapid perturbations in man have stimulated the present investigation.EMG activities were recorded from the fully conscious animal using chronic electrodes implanted in various muscles (splenius, quadriceps femoris, soleus, and tibialis anterior). For testing, the monkey was seated in a special chair suspended from an electromagnet and unexpectedly dropped 90 cm. EMG responses were recorded in three randomly presented conditions: with normal motion of visual world (N), with visual world stabilized with respect to the head (S) using a box covered inside by a black and white checkboard pattern surrounding the animal's head, and in total darkness (D).Results showed that condition S is accompanied in all tested muscles by a significant decrease in the EMG response; this effect is particularly evident in the interval 60–120 ms but may occur earlier. Condition D is in most of the cases accompanied by a less important decrease which is situated between condition N and condition S. These results are in contrast to previous conclusions of other authors which negated the role of vision in similar situations.  相似文献
10.
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