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41.
目的探讨单蒂横行腹直肌肌皮瓣乳房再造术中Ⅳ区皮瓣的取舍。方法通过16例实施单蒂横行腹直肌肌皮瓣乳房再造术,术中观察皮瓣的皮色、断面出血颜色,并利用近红外血氧监测仪测定皮瓣各区的组织血氧饱和度,决定Ⅳ区皮瓣的取舍。术后观察指标包括术后并发症及美学效果。结果16例中5例Ⅳ皮瓣的肤色正常、断面出血呈鲜红色而非暗红色、组织血氧饱和度不低于Ⅲ区组织血氧饱和度的95%。在接受了保留Ⅳ区皮瓣的单蒂横行腹直肌肌皮瓣乳房再造术后,再造乳房全部成活,无严重术后并发症,患者对再造乳房均很满意。结论近红外血氧无创检测有助于决定Ⅳ区皮瓣的取舍。有选择地实施保留Ⅳ区皮瓣的单蒂横行腹直肌肌皮瓣乳房再造术,可用于大面积胸壁缺损或乳腺尾叶的修复重建。 相似文献
42.
43.
质子磁共振波谱对颞叶癫癎的诊断价值 总被引:3,自引:1,他引:2
目的:评价磁共振质子波谱(H MRS)对颞叶癫癎的诊断价值.方法:对20例健康人和18例颞叶癫癎病人进行1H MRS采集,并定量分析了癫痫病人的N-乙酰天门冬氨酸(NAA)、肌酸(Cr)和胆碱复合物(Cho)等代谢产物的变化.结果:癫癎病人致癫灶NAA峰以及NAA/(Cho cr)、NAA/Cr和NAA/Cho比值低于病灶对侧,亦低于健康对照组.正常对照组NAA/(Cho Cr)值平均为0.78,双侧差别小于0.07.我们以NAA/(Cho Cr)值<0.68和双侧NAA/(Cho Cr)比值的差别>0.07为判断标准,18例颞叶癫癎病人中,16例为单侧MRS异常,2例为双侧异常.结论:质子磁共振波谱能无创性探测脑组织内生化及代谢改变,是诊断颞叶癫癎的有效手段之一. 相似文献
44.
抗抑郁治疗对功能性消化不良的辅助治疗作用 总被引:6,自引:0,他引:6
功能性消化不良是指具有上腹痛、上腹胀,早饱、暖气、食欲不振、恶心、呕吐等上腹不适症状,经检查排除引起这些症状的器质性疾病的一组临床综合征。在经济、科技、工业化高度发展的社会,已经成为危害人们健康状况和生活质量的最常见的消化系统疾病,因而受到广泛重视。欧美的流行病学调查表明,普通人群中有消化不良症状者占19%-41%,在我国人群中总的患病率为20%。普通门诊中占20%-40%,在消化专科中占60%-70%。FD的发病机制复杂,部分患者存在精神心理的异常,本文通过对FD患者进行抑郁自评量表(zuag评分)评定和抗抑郁药物治疗,旨在探讨二者关系及抗抑郁治疗FD的疗效。 相似文献
45.
BRIAN J. STOCKMAN CAROL A. BANNOW ROBERT M. MICELI MICHAEL E. DEGRAAF H. DAVID FISCHER CLARK W. SMITH 《Chemical biology & drug design》1995,45(1):11-16
Epitope libraries provide a method to identify peptide ligands for antibodies, receptors or other binding proteins. As such, they provide a powerful tool to rapidly identify lead ligands in the drug discovery process. In an attempt to correlate structural information with the results from peptide screening, we have used NMR spectroscopy of peptide/antibody complexes to demonstrate that core residues identified through a two-stage selection process undergo a larger structural change upon binding antibody than do positions in the peptide amenable to a variety of side chains. The model system used was the M2 monoclonal antibody/Flag? octapeptide epitope system. We have analyzed two peptides: Ac-Asp-Tyr-Lys-Leu-Gly-Asp-Asp-Leu-NH2 (peptide l), which contains several non-core positions randomized, and Ac-Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Leu-NH2 (peptide 2), which closely corresponds to the original Flag? sequence. Enrichment of the peptides with 15N facilitated the investigation by permitting spectral editing of the peptide resonances in the presence of antibody. For peptide 1 the absolute shifts for the free vs. Fab-bound peptide were found to be largest for the amide groups of Asp-1 and Asp-6, in agreement with classification of these residues as critical by the phage display library selection process. For peptide 2 the largest absolute shifts were observed for Asp-1 and Asp-4, with the other aspartic acid residues also showing significant but smaller changes. © Munksgaard 1995. 相似文献
46.
Khema R. Sharma Jane Kent-Braun Mark A. Mynhier Michael W. Weiner Robert G. Miller 《Muscle & nerve》1995,18(12):1403-1411
The goals of this study were to investigate muscle fatigue in patients with multiple sclerosis (MS), and to determine the relationships between muscle fatigue, clinical status, and perceived fatigue. The fatigability of the anterior tibial muscle was quantitated in patients and controls during 9 min of intermittent stimulation (used to eliminate central sources of muscle fatigue). During exercise, the decline in tetanic force, phosphocreatine, and intracellular pH was greater in patients than in controls. The compound muscle action potential amplitude did not decrease during exercise, indicating that there was no failure of neuromuscular transmission during fatigue. Thus, the excessive fatigue in MS developed from sources beyond the muscle membrane. Following exercise, the recovery of tetanic force was delayed in patients (a pattern that suggests abnormal excitation–contraction coupling), whereas the recovery of metabolites was complete in both groups. Muscular fatigue was correlated with clinical disability but not with perceived fatigue. These results suggests that fatigue in MS has both central (perception, upper motor neuron dysfunction) and peripheral (impaired metabolism and excitation–contraction coupling) components.© 1995 John Wiley &Sons, Inc. 相似文献
47.
OBJECTIVE: To indicate whether the double peaked N(1) to gaps in continuous white noise is a composite of onset and offset responses to transients or whether it reflects higher processing such as change or mismatch detection and to assess the role of attention in this process. METHODS: Evoked potentials were recorded to two binaural stimulus types: (1) gaps of different durations randomly distributed in continuous white noise; and (2) click pairs at intervals identical to those between gap onsets and offsets in the continuous noise stimulus. Potentials to these stimuli were recorded while subjects read a text and while detecting gaps in noise or click pairs. RESULTS: Potentials were detected to all click pairs and to gaps of 5 ms or longer, corresponding to the subjects' psychoacoustic gap detection threshold. With long gap durations of 200-800 ms, distinct potentials to gap onset and gap offset were observed. The waveforms to all click pairs and to offsets of long gaps were similar and single-peaked, while potentials to gaps of 10 ms and longer, and potentials to onsets of long gaps were double-peaked, consisting of two N(1) negativities, 60 ms apart, irrespective of gap duration. The first (N(1a)), was more frontal in its distribution and similar to that of clicks. The second (N(1b)) peak's distribution was more central/temporal and its source locations and time course of activity were distinct. No effects of attention on any of the varieties and constituents of N(1) were observed. CONCLUSIONS: Comparing potentials to gap onsets, to click pairs and to gap offsets, suggests that potentials to gap onsets involve not only sound onset/offset responses (N(1), N(1a)) but also the subsequent pre-attentive perception of the cessation of an ongoing sound (N(1b)). We propose that N(1b) is distinct from change or mismatch detection and is associated with termination of an ongoing continuous stimulus. We propose to call it the N(egation)-process. SIGNIFICANCE: A constituent of the N(1) complex is shown to be associated with the pre-attentive perception of termination of an ongoing stimulus and to have distinct scalp distribution and intracranial sources. 相似文献
48.
Julie Hicks Patrick Jenessa C. Johnson R. Turner Goins David K. Brown 《Quality of life research》2004,13(5):959-967
This study investigates functional disability among some of the nation's most vulnerable older adults: rural Medicaid recipients. Data were provided by 221 older adults (mean age = 75.9 years; 82% women) who were receiving community-based long-term care services through Medicaid. Participants self-reported functional ability involving the completion of six basic activities of daily living (BADLs), three cognitive instrumental activities of daily living (IADLS), and four physical IADLs. Self-reports of depressed affect and the number of physical health conditions were also obtained. Path analysis was used to examine all of the associations among age, gender, number of chronic health conditions, depressed affect and functional disability. The tested model was significant [chi2 (DF = 3, n = 221) = 5.052, p = 0.168; TLI = 0.945; CFI = 0.992; RMSEA = 0.056] and explained 45.1% of the variance in BADL disability. Depressed affect significantly predicted disability in cognitive IADLs and physical IADLs, which predicted disability in BADLs. Age and gender had indirect effects on BADL, through their association with cognitive IADLs and physical IADLs. The number of chronic health conditions exerted both indirect and direct effects on BADL disability. Results are discussed within the context of the growing literature that suggests the importance of psychological variables as predictors of functional disability. Moreover, we discuss whether community-based long-term care is appropriate for older adults with high levels of functional disability. 相似文献
49.
Ivan Tkác Pierre-Gilles Henry Peter Andersen C Dirk Keene Walter C Low Rolf Gruetter 《Magnetic resonance in medicine》2004,52(3):478-484
An efficient shim system and an optimized localization sequence were used to measure in vivo 1H NMR spectra from cerebral cortex, hippocampus, striatum, and cerebellum of C57BL/6 mice at 9.4 T. The combination of automatic first- and second-order shimming (FASTMAP) with strong custom-designed second-order shim coils (shim strength up to 0.04 mT/cm2) was crucial to achieve high spectral resolution (water line width of 11-14 Hz). Requirements for second-order shim strengths to compensate field inhomogeneities in the mouse brain at 9.4 T were assessed. The achieved spectral quality (resolution, S/N, water suppression, localization performance) allowed reliable quantification of 16 brain metabolites (LCModel analysis) from 5-10-microL brain volumes. Significant regional differences (up to 2-fold, P < 0.05) were found for all quantified metabolites but Asp, Glc, and Gln. In contrast, 1H NMR spectra measured from the striatum of C57BL/6, CBA, and CBA/BL6 mice revealed only small (<13%, P < 0.05) interstrain differences in Gln, Glu, Ins, Lac, NAAG, and PE. It is concluded that 1H NMR spectroscopy at 9.4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models. 相似文献
50.
目的 :研究COPD肺心病急性加重期多个器官的受损情况。方法 :采用日本OLYMPUS公司AU10 0 0全自动生化分析仪测量 10 9例肺心病急性加重期患者的 17项血生化指标。并与 110例健康体检者进行对照研究。结果 :两组之间血肌酐 (Cr)差异不显著 (P >0 .0 5 ) ,总胆红素 (TBIL)及空腹血糖 (GLU)差异显著 (P <0 .0 5 ) ,其余 14项生化指标P值均 <0 .0 1,两组间差异非常显著。结论 :COPD肺心病急性加重期除了心力衰竭 ,呼吸衰竭之外 ,还常常伴有肝损害、肾损害、高血糖、低脂低胆固醇血症、低蛋白血症及营养不良。保肝护肾 ,注意血糖血脂及营养支持治疗不容忽视 相似文献