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11.
目的:观察地震灾害对分娩的影响。方法:对我院2008年5月12日至2008年6月12日在地震期间分娩的216例产妇进行回顾性分析。结果:阴道分娩率较地震前比较明显上升,剖宫产率明显下降。结论:地震灾害致孕妇的心理发生变化,导致阴道分娩率上升剖宫产率明显下降。  相似文献   
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微血管减压术治疗舌咽神经痛16例临床分析   总被引:4,自引:1,他引:3  
目的 研究舌咽神经痛 (glossopharyngealneuralgia,GPN)手术治疗的最佳术式 ,评估微血管减压手术(microvasculardecompression ,MVD)的效果、并发症和随访结果 ,探讨可能的治疗机制。方法  2 0 0 0年 12月到2 0 0 3年 10月间 ,16例GPN患者接受了MVD ,无一例行神经根切断术。患者全部进行了电话或信件随访。结果 15例患者术后疼痛消失 ,1例患者为不典型GPN ,术后疼痛减轻。 1例患者术后出现轻度声音嘶哑和吞咽困难 ,1例患者出现偶发干咳。本组患者平均随访时间为 14 .1± 6 .3月 ,随访期间无一例复发。结论 MVD是治疗舌咽神经痛的一种安全、有效的手术方式 ,尤其适用于典型的GPN患者。  相似文献   
14.
The mechanisms underlying neurologic deficits and delayed neuronal death after ischemia are not fully understood. In the present study, we report that transient cerebral ischemia induces accumulation of ubiquitinated proteins (ubi-proteins) in postsynaptic densities (PSDs). By immunoelectron microscopy, we demonstrated that ubi-proteins were highly accumulated in PSD structures after ischemia. On Western blots, ubi-proteins were markedly increased in purified PSDs at 30 minutes of reperfusion, and the increase persisted until cell death in the CA1 region after ischemia. In the resistant DG area, however, the changes were transient and significantly less pronounced. Deposition of ubi-proteins in PSDs after ischemia correlates well with PSD structural damage in the CA1 region as viewed by electron microscopy. These results suggest that the ubiquitin-proteasome system fails to repair and remove damaged proteins in PSDs. The changes may demolish synaptic neurotransmission, contribute to neurologic deficits, and eventually lead to delayed neuronal death after transient cerebral ischemia.  相似文献   
15.
The ability of nicotine to induce a cytoprotective or neuroprotective action occurs through several down-stream mechanisms. One possibility is that the drug increases the expression of tyrosine kinase A (TrkA) nerve growth factor (NGF) receptors. Certain β-amyloid peptides (e.g., Aβ1–42) have been shown to bind with high affinity to α7 nicotinic receptors and thus interfere with a potentially neurotrophic influence. Treatment of differentiated PC-12 cells with nicotine produced a concentration-dependent increase in cell-surface TrkA receptors that occurred concomitantly with cytoprotection. The effect of nicotine was blocked by either of the α7 receptor antagonists α-bungarotoxin (α-BTX) or methyllycaconatine. The cytoprotective action of nicotine also was inhibited by pretreatment with 10–100 nM Aβ1–42. Nicotine also was administered (four injections of 30 μg, spaced evenly over 24 h) to rats by direct injection into a lateral cerebral ventricle. Brain TrkA expression was increased significantly in hippocampus and entorhinal cortex (up to 32% above control), with no changes found in cerebral cortex or hypothalamus. The nicotine-induced increases in TrKA expression in hippocampus and entorhinal cortex were significantly inhibited by 10 μg α-BTX or by 10 nmol Aβ1–42. Therefore, physiologically relevant concentrations of Aβ1–42 can prevent nicotine-induced TrkA receptor expression in brain regions containing cholinergic neurons susceptible to the neurotoxicity associated with Alzheimer’s disease.  相似文献   
16.
Background: Only limited data exist comparing differences in sensory function and responses to neural blockade in infant and adult rats. Therefore, the authors sought (1) to compare baseline thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats; and (2) to compare the effects of sciatic nerve blockade on thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats.

Methods: Infant, adolescent, and adult rats were evaluated for proprioceptive, thermal, and mechanical nociceptive and motor function before and after sciatic blockade using a detailed neurologic examination.

Results: Mechanical and thermal nociception were present in all rats, starting from age 1 day. The withdrawal reflex latency to pinch was rapid at all ages, whereas that reaction to thermal stimulus depended on both age and temperature. In contrast, the tactile placing response and hopping response were absent at birth and developed completely during the first 10 days of life. The extensor postural thrust was absent in the first 2 weeks of life and developed variably during the first 50 days of life. Sciatic blockade duration is shorter in infant rats than in adult rats receiving the same dose per kilogram. A brief halothane general anesthetic at the time of sciatic injection in infant or adult rats does not alter the duration of blockade.  相似文献   

17.
Penetration of Schistosoma japonicum cercaria into host skin.   总被引:1,自引:0,他引:1  
The anterior part of Schistosoma japonicum cercaria is a specialized head organ which can slightly stretch out and retract. There are three different types of large unicellular glands in cercarial body, consisting of one head gland, 2 pairs of pre- and 3 pairs of postacetabular glands. These glands differ in position, gross feature, histochemistry and functions. Both polysaccharase and protease activities are demonstrated in the secretions from these glands. Mode of cercarial penetration is described in detail and the penetration is effected by a combination of lytic secretions and mechanical movements. The schematic representation of the process of cercarial penetration is presented. The dynamic distributions of schistosomula in skin at different time intervals after skin penetration in various mammalian hosts are shown. Some newly transformed schistosomula die while penetrating into the skin of 7 mammalian species and the mortality rate varies with the host species, and that can also be affected by the age of cercariae following emergence from the snail. Some physiological aspects between cercariae and newly transformed schistosomula are compared. In contrast to cercariae, schistosomula are saline-adapted and water-intolerant. They were modified histochemically and antigenically.
  相似文献   
18.
临床输液监控系统的设计   总被引:5,自引:0,他引:5  
本文针对临床输液过程中出现的漏、停、输液速度改变等各种问题,讨论了一由单台微机和多个单片机通讯实现的多床输液自动监控、自动反应、自动报答系统的可行性,并给出了主要部分的硬件、软件设计方法。  相似文献   
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20.
We have adapted the simple and sensitive McAb-antigen spot test (AST) for evaluating the efficacy of anti-Leishmania chemotherapy. Serum samples from 37 kala-azar patients were tested by McAb-AST, and all showed definite positive reactions before treatment. After a course of antimony treatment, 20 turned negative, coupled with the disappearance of clinical symptoms; another 12 cases responded with weak positivity accompanied by an improvement of clinical manifestations; and the remaining 5 antimony-resistant patients showed strong positive reactions, with their conditions gradually worsening. Furthermore, all 6 cases in which the diagnosis was missed by the bone marrow smear method turned McAb-AST negative after chemotherapy. These results suggest that McAb-AST can be used to evaluate the efficacy of chemotherapy as well as to avoid missed diagnosis by the bone marrow smear method.  相似文献   
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