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41.
老年病人鼻饲方法的改进 总被引:16,自引:2,他引:14
目的探讨增加置管深度并抬高床头对预防老年鼻饲病人食物反流的效果。方法将 5 75例需鼻饲的卧床老年病人按鼻饲医嘱时间顺序及不平衡指数最小原则分成三组 ,分别给予教科书中的常规置管深度置管 (对照组 )、置管深度延长 10cm(观察 1组 )、置管深度延长 10cm并抬高床头 30~ 45°(观察 2组 )进行鼻饲。结果三组病人食物反流率比较 ,P <0 .0 1;观察 1、2组分别与对照组比较 ,P <0 .0 5、P <0 .0 1;观察 1组与观察 2组比较 ,P <0 .0 1。增加置管深度并抬高床头其食物反流率最低 ,仅增加置管深度次之 ,常规置管最高。结论增加置管深度并抬高床头可显著降低老年鼻饲病人食物反流发生率。 相似文献
42.
宫腔镜电切术治疗子宫纵隔23例临床分析 总被引:1,自引:0,他引:1
目的:探讨子宫纵隔患者接受宫腔镜电切术治疗后的妊娠结局。方法:回顾性分析23例子宫纵隔患者接受宫腔镜下子宫纵隔电切术后的妊娠结局。结果:23例子宫纵隔患者中,子宫完全纵隔5例,不完全纵隔18例,23例均在超声监视下完成手术,平均手术时间25min,平均出血30ml。与术前相比,术后足月活产率从4.35%增至48.83%,流产率从85.55%降至30.43%,具有显著性差异(P<0.01)。结论:宫腔镜电切术治疗子宫纵隔是安全、有效地治疗方法,能显著提高足月活产率,明显降低流产率。 相似文献
43.
Dr. med. Thorsten Schäfer Heike Vogelsang 《Somnologie - Schlafforschung und Schlafmedizin》2002,6(2):79-84
Summary Question of the study Nasal continuous positive airway pressure (CPAP) prevents collapse of the upper airway during sleep in patients with obstructive sleep apnea provided that a positive transmural pressure can be maintained during inspiration. We examined pressure-flow characteristics in seven CPAP and bilevel devices during spontaneous breathing.
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H2 O) and adapted to a pneumotachograph using a standard CPAP hose and an outlet valve. We continuously measured flow, volume and pressure during resting ventilation and increasing voluntary hyperventilation and analysed the dependence of the variables on a breath-to-breath basis.
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献
44.
Effect of CNTF on low-affinity NGF receptor expression by cultured neurons from different rat brain regions. 总被引:4,自引:0,他引:4
Our previous work indicated that in E14 embryonic rat spinal cord cultures ciliary neuronotrophic factor (CNTF) exerted (1) a survival-promoting effect on motor neurons and on a large population of unidentified neurons, and (2) a regulatory role on the expression of ChAT and low affinity NGF receptor (LNGFR) in a population of small/medium-sized neurons. In the present study, we examined the effect of CNTF on the expression of LNGFR in cultures of different regions from the E18 embryonic rat brain, namely cortex, septum, striatum, mesencephalon, hippocampus, brainstem, and cerebellum. The number of LNGFR-positive neurons (stained with the 192-IgG monoclonal antibody) was determined in untreated cultures and in cultures treated for 6 days (0-6) with human recombinant CNTF. To distinguish between effects on survival and on LNGFR expression, experiments were performed in which CNTF was administered only for the last 48 h of the culture (from days 4-6). LNGFR positive neurons were found in the cultures of all the regions examined. In each one of them, CNTF increased the number of LNGFR-positive neurons by three- to fourfold after 6 days of treatment. In the striatum, septum, mesencephalon, and cerebellum, the effect of CNTF was shown to be on the regulation of LNGFR expression and not on survival. In cultures from the cortex, hippocampus and brainstem, a survival-promoting role of CNTF could be demonstrated. The effect of CNTF was dose dependent, with half-maximal effects (ED50) achieved at 2-4.5 TU/ml for all the brain regions. Maximal effects were reached at 100-250 TU/ml. From these results, we conclude that (1) there exists a wide spectrum of CNTF-responsive neurons in the central nervous system, and (2) CNTF plays an important and widespread role in regulating the expression of the LNGFR in neurons. 相似文献
45.
目的 探讨鼻眶筛骨折的手术入路、骨折复位与坚固内固定及合并眼球内陷的处理方法。方法 对 17例鼻眶筛骨折患者进行回顾性研究 ,根据CT结果与Fedor骨折分型分为三型 ,其中Ⅰ型 1例 ,Ⅱ型 7例 ,Ⅲ型 9例 ;13例选用鼻根正中入路 ,3例鼻旁入路 ,7例需同时附加眶下切口。 8例合并眼球内陷者采用眼球赤道后方碘仿纱条填塞与植骨矫正法。结果 ①本组病例平均内眦宽度和内眦宽度 /外眦宽度比例从 ( 35± 7)mm、( 37± 8) %恢复到 ( 32± 4 )mm、( 35± 7) %比较正常水平 ;②面部外形全部恢复到正常或接近正常 ;③ 8例眼球内陷患者术后 6例恢复到基本正常 ,2例术后仍有轻度凹陷 ,5例复视术后全部消失。结论 鼻根正中入路附加眶下切口可充分显露骨折片 ,结合坚固内固定技术可使骨折片解剖复位 ;内眦韧带复位固定是本手术关键所在 ,重建正常眶内容积和眶内容物准确复位 ,以解决眼球内陷和眼球运动受限问题 相似文献
46.
The presence and binding properties of epidermal growth-factor receptors (EGF-Rs) in different cell types purified from the rat medial septal area in culture were investigated. We report that astrocytes, oligodendrocytes and neurons from this area possess EGF-Rs while microglia do not. EGF-binding sites are detectable on astrocytes derived from the medial septum of both embryonic and neonatal rats. Scatchard analysis of the data for astrocytes from the fetal rats show that EGF specifically binds to both high- (Kd = 7.21 × 10−10 M, Bmax = 3602 receptors/cell) and low-affinity (Kd = 3.99 × 10−8 10−8 M, Bmax = 6,265 receptors/cell) receptors on these cells. On the other hand, astrocytes purified from neonatal tissue possess a greater number of high-affinity receptors (Bmax = 10,938 receptors/cell) when compared with the embryonic astroglia. With time in culture, the number of both types of receptors on neonatal astrocytes decreases. Oligodendrocytes also possess high- and low-affinity EGF-Rs with dissociation constants of 3.25 × 10−10 M and 3.85 × 10−8 M, respectively. The number of receptors on oligodendrocytes is significantly lower than those on neonatal astrocytes (Bmax = 1185 and 25,081 receptors/cell for high- and low-affinity binding sites, respectively). Finally, neurons from this area also exhibit two different EGF-R types with dissociation constants similar to those described for astrocytes. As the number of receptors/neuron (Bmax = 136 and 1159 receptors/cell for high- and low-affinity binding sites, respectively) appears to be extremely low, it is possible that EGF specifically binds only to a subpopulation of neurons from this area. These studies demonstrate which cell types in the developing medial sepal area posses EGF-Rs and provide a detailed characterization of these binding sites. These EGF-R-bearing cells may be potential targets for this growth factor or for transforming growth factor α in this brain area. 相似文献
47.
Bülent Gül Sezer Kulaçoglnu Dr. Muammer Yükse Handan Dogan Ali Ihsan Ökten 《Neurosurgical review》1997,20(1):59-61
Esthesioneuroblastoma is an uncommon malignant neoplasm that arises from olfactory mucosa, often with intracranial extension.A case report of the youngest victim in the literature (2-year-old boy) is presented. 相似文献
48.
R. B. Gore E. A. Hadi M. Craven F. I. Smillie T. J. O'Meara† E. R. Tovey† A. Woodcock A. Custovic 《Clinical and experimental allergy》2002,32(6):856-859
BACKGROUND: Assessment of personal exposure to dust mite allergen has relied on proxy measures. Only recently has a means to directly measure inhaled allergen particle number become available (the intra-nasal air sampler). OBJECTIVE: To quantify inspired dust mite group 1 and group 2 allergen-bearing particles in bed in undisturbed conditions prior to sleep by nasal air sampling and to investigate the relationship between inhaled particles and reservoir allergen levels. METHODS: Twelve volunteers wore nasal samplers in bed for 6 evenings, nose-breathing in undisturbed conditions. Allergen-bearing particles ('halos') were detected by immunostaining for Der p 1, Der p 2, or Der p 1 and Der p 2 together, and counted by light microscopy. Count data were square root transformed for analysis of variance. Mattress dust samples were assayed for Der p 1 and Der p 2 concentrations. RESULTS: Square root detransformed mean particle counts per 30-min sample were: Der p 1, 4.22; Der p 2, 5.9; Der p 1 + Der p 2, 4.87; and for all samples, 5.01, with no difference between the groups. With replicate samples, halo number correlated significantly with mattress allergen concentrations (Der p 1 r = 0.80, P < 0.01; Der p 2 r = 0.68, P < 0.02). CONCLUSION: Nasal air sampling can be used to quantify nocturnal Der p exposure in undisturbed conditions in an area with moderate exposure to mite allergen and can provide a direct measure of inhaled mite allergen. The choice of either Der p 1 or Der p 2 is appropriate for this purpose. 相似文献
49.
50.
R P Vertes 《The Journal of comparative neurology》1992,326(4):595-622
The projections of the supramammillary nucleus (SUM) were examined in the rat by the anterograde anatomical tracer Phaseolus vulgaris leucoagglutinin (PHA-L). The majority of labeled fibers from SUM ascended through the forebrain within the medial forebrain bundle. SUM fibers were found to terminate heavily in the hippocampal formation, specifically within the granule cell layer and immediately adjoining molecular layer of the dentate gyrus. In addition, SUM fibers were shown to distribute densely to several structures with strong connections with the hippocampus, namely, the nucleus reunions of the thalamus, the medial and lateral septum, the entorhinal cortex, and the endopiriform nucleus. SUM fibers were also shown to project significantly to several additional subcortical and cortical sites. The subcortical sites were the dorsal raphe nucleus, the midbrain central gray, the fields of Forel/zona incerta, the dorsomedial hypothalamic area, midline/intralaminar nuclei of the thalamus (posterior paraventricular, rhomboid, central medial, intermediodorsal, and mediodorsal), the medial and lateral preoptic areas, the bed nucleus of the stria terminalis, the substantia innominata, the vertical limb of the diagonal band nucleus, and the claustrum. The cortical sites were the occipital, temporal, parietal, and frontal cortices. Some notable differences were observed in projections from the lateral as compared to the medial SUM. For example, fibers originating from the lateral SUM distributed heavily to the hippocampal formation and parts of the cortex, whereas those from the medial SUM projected sparsely to these two regions. The SUM projections to the hippocampal formation and associated structures may serve as the substrate for a SUM involvement in the generation of the theta rhythm of the hippocampus and the gating of information flow through the hippocampal formation. 相似文献