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131.
Changes in the cupper (Cu) and zinc (Zn) concentrations have been reported previously in idiopathic dilated cardiomyopathy (IDCMP). As a result of controversial results, the aim of this study was to compare the Zn and Cu concentrations and Zn/Cu ratio of IDCMP patients to healthy volunteers. In addition, the correlation of Cu and Zn levels with age has been evaluated. The study population consisted of 18 IDCMP patients and 27 healthy volunteers. IDCMP patients had normal angiography with echocardiography supporting cardiomyopathy without pericardial and valvular diseases. Exclusion criteria were renal or hepatic insufficiency, alcohol usage, and intake of supplements containing Cu or Zn within 1 week ago. Cu and Zn levels have been assayed with atomic absorption spectrophotometry. Statistical analysis was performed with SPSS 10 software with independent sample t test for comparing the level of Cu and Zn of IDCMP patients with normal subjects and Pearson correlation to determine the correlation between numeric data. P < 0.05 was considered as significant differences. There was a trend for a lower Zn level in IDCMP patients compared to healthy volunteers. (0.97 ± 0.25 mg/l vs. 1.12 ± 0.42 mg/l, respectively). The mean Cu levels of IDCMP and normal subjects were 1.33 ± 0.20 mg/l and 1.31 ± 0.23 mg/l, respectively. There was a significant difference in Zn/Cu ratio among patients based on the NYHA classification of heart failure (P = 0.003). Age was negatively correlated with Zn levels in IDCMP group (P = 0.037) and positively with Cu levels in healthy volunteers (P = 0.012). A lower Zn level in IDCMP patients compared to healthy volunteers and specially a significant difference in Zn/Cu ratio of patients based on their NYHA classification would suggest a critical role of zinc and Cu imbalance in development of IDCMP.  相似文献   
132.
In three experiments, subjects tracked intensity of nasal irritation during sustained presentation of carbon dioxide in the nose. Experiment 1 showed that: (i). functions of peak intensity vs. concentration and latency to first non-zero ratings agreed with published literature, thereby supporting the validity of the technique; (ii). on average, rated intensity peaked approximately 3-4 s after stimulus-onset and began to fall rapidly thereafter; (iii). large and stable individual differences in temporal dynamics occurred. Experiment 2 replicated experiment 1 with some methodological refinements. In experiment 3, application of the technique revealed that the nose regains sensitivity with very brief (300-500 ms) interruptions in presentation of carbon dioxide. In short: (i). the method developed here provides a temporally fine-grained tool to study the time-course of nasal irritation, and (ii). nasal irritation from carbon dioxide shows relatively rapid temporal dynamics.  相似文献   
133.
Ostrovskaya  O.  Lishko  P.  Beketov  A.  Krishtal  O. 《Neurophysiology》2002,34(2-3):194-194
FLRFa, FIRFa, YMRFa, and some other peptides are found to slow down the kinetics of desensitization of proton-gated currents in rat trigeminal neurons but not in HEK-293T cell culture transfected with ASIC. The observed heterogeneity of peptide action in sensory neurons leads to a suggestion that FMRFa-related peptides may selectively affect transient current components of ASIC and DRASIC/DRASIC-MDEG2 heteromers.  相似文献   
134.
In the nose, the capacity to detect and react to volatile chemicals is mediated by two separate but interrelated sensory pathways, the olfactory and trigeminal systems. Because most chemosensory stimulants, at sufficient concentration, produce both olfactory and trigeminal sensations (i.e., stinging, burning or pungent), it is relevant to seek how these anatomically distinct systems could interact. This study was designed to evaluate by psychophysical measurements the modifications of the olfactory sensitivity of 20 subjects to phenyl ethyl alcohol (PEA) and butanol (BUT), after trigeminal stimulation with allyl isothiocyanate (AIC). Thresholds obtained in two separate sessions, one with and the other without previous trigeminal stimulation, were compared using a two-alternative forced-choice procedure, with a classical ascending concentrations method. The results showed that, whatever the odorant (PEA or BUT), AIC trigeminal activation produced a decrease in the olfactory thresholds, corresponding to an increase in olfactory sensitivity. These data confirm that in physiological conditions the trigeminal system modulates the activity of olfactory receptor cells but do not exclude the possibility of a central modulation of olfactory information by trigeminal stimuli. These findings are discussed in terms of methodological and physiological conditions.  相似文献   
135.
1. The present study was undertaken to localize and characterize bradykinin (BK) binding sites in brains from Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR).2. Serial sections of brains were cut from adult WKY and SHR and specific [125I-Tyr0]bradykinin ([125I-Tyr0]BK) binding was determined using in vitro quantitative receptor autoradiographic techniques.3. Specific binding of [125I Tyr0]BK was localized in the medulla oblongata to the regions of the nucleus of the solitary tract (NTS), area postrema (AP), dorsal motor nucleus of the vagus (X), and caudal subnucleus of the spinal trigeminal nucleus in both strains of rat. The specific binding (85–90% of total binding) was of high affinity and saturable with K D values in the range of 100 pM and a B max of 0.75 fmol per mg tissue equivalent in the NTS–X–AP complex of both the WKY and SHR. In competition studies, the rank order of potencies was similar in both strains with BK = Lys-BK > icatibant >>> DesArg9-BK. The B2 receptor antagonist icatibant inhibited [125I-Tyr0]BK binding with a K i value of 0.63 ± 0.19 nM in WKY and 0.91 ± 0.73 nM in SHR, while K i values for the B> 1 receptor agonist DesArg9-BK were 1475 ± 1055 and 806 ± 362 nM in WKY and SHR, respectively.4. Our finding of specific high-affinity [125I-Tyr0]BK B2 binding sites in the NTS, AP, and the X of WKY and SHR is important because these brain areas are associated with central cardiovascular regulation. However, alterations in BK B2 receptors in the medulla that could contribute to the hypertensive state in the SHR were not detected.  相似文献   
136.
摘要 目的:研究特发性肺纤维化(IPF)患者血清血管生成素-2(Ang-2)、潜在转化生长因子结合蛋白2(LTBP2)、趋化因子配体14(CXCL14)水平与预后的关系。方法:选取2019年3月~2020年3月河北医科大学第二医院东院区呼吸内科收治的100例IPF患者作为研究对象。将其按照随访结局分成预后不良组59例及预后良好组41例。比较两组Ang-2、LTBP2、CXCL14水平、肺功能指标、实验室指标以及一般资料,Pearson相关分析血清Ang-2、LTBP2、CXCL14水平与肺功能指标的相关性,多因素Logistic回归分析IPF患者预后的影响因素,受试者工作特征(ROC)曲线分析Ang-2、LTBP2、CXCL14对IPF患者预后的预测价值。结果:预后不良组血清Ang-2、LTBP2、CXCL14水平均高于预后良好组(P<0.05)。预后不良组第1s用力呼气容积(FVC1)、一氧化碳弥散量占预计值百分比(DLCO%)、动脉血氧分压(PaO2)/氧体积分数(FiO2)均低于预后良好组,而吸烟史、肺动脉高压人数占比高于预后不良组(P<0.05)。Pearson相关性分析显示:IPF患者Ang-2、LTBP2、CXCL14水平均和FVC1、DLCO%呈负相关(P<0.05)。多因素Logistic回归分析结果显示:FVC1、DLCO%、PaO2/FiO2、吸烟史、肺动脉高压以及血清Ang-2、LTBP2、CXCL14水平是IPF患者预后不良的影响因素(P<0.05)。ROC曲线分析结果显示:血清Ang-2、LTBP2、CXCL14三项联合检测预测IPF患者预后的曲线下面积高于上述三项指标单独检测。结论:IPF患者血清Ang-2、LTBP2、CXCL14水平与其预后密切相关,可作为评估其预后的辅助性指标。  相似文献   
137.
摘要 目的:研究丹参凝胶治疗对特应性皮炎小鼠模型皮肤屏障功能、表皮增生以及免疫功能的影响。方法:30只C57BL/6小鼠被随机分为Control组、AD组和SG组,每组10只。AD组和SG组背部涂抹对二硝基氟苯建立特应性皮炎小鼠模型,SG小鼠在模型建立成功后涂抹丹参凝胶治疗3周,Control组和AD组涂抹凡士林作为对照。3周后,测量所有小鼠经皮水分丢失量( TEWL) 、皮肤厚度、脾脏指数、胸腺指数,血清IgE、IFN-γ和IL-4,脾脏树突状细胞、Th1和Th2细胞比例。结果:丹参凝胶治疗3周后,AD组和SG组小鼠TEWL、皮肤厚度、脾脏指数、胸腺指数,血清IgE、IFN-γ和IL-4含量,以及脾脏Th2细胞比例均显著高于对照组正常小鼠(P<0.05),而脾脏树突状细胞、Th1细胞和Th1/Th2细胞比例均显著低于对照组正常小鼠(P<0.05);与AD组小鼠相比,SG组小鼠TEWL、皮肤厚度、脾脏指数、胸腺指数,血清IgE、IFN-γ和IL-4含量,以及脾脏Th2细胞比例均显著降低(P<0.05),而脾脏树突状细胞、Th1细胞和Th1/Th2细胞比例均显著升高(P<0.05)。结论:丹参凝胶具有保护特应性皮炎样小鼠皮肤屏障功能和抑制表皮增生的功能,并且可以影响特应性皮炎样小鼠脾脏树突状细胞和辅助性T细胞比例。  相似文献   
138.
摘要 目的:探讨与研究芬太尼联合电针通过介导组蛋白去乙酰化酶2(histone deacetylase 2,HDAC2)途径调节糖尿病大鼠周围神经痛的作用机制。方法:将建模成功的糖尿病周围神经痛大鼠(n=36)随机平分为三组-模型组、芬太尼组与电针组,芬太尼组、模型组分别经尾静脉泵注1.0 μg/kg/min芬太尼与等剂量的磷酸盐缓冲液5 min,1次/d。电针组在芬太尼治疗的基础上给予电针治疗,1次/d,均共治疗2周。治疗第1周与第2周,对大鼠进行体重称重,采用双抗体酶联免疫夹心法测血清胰岛素浓度,动态足底触觉仪检测大鼠机械痛阈,免疫印迹检测HDAC2蛋白相对表达水平。结果:芬太尼组与电针组在治疗第1周、第2周的体重都明显高于模型组(P<0.05),电针组也明显高于芬太尼组(P<0.05)。芬太尼组与电针组在治疗第1周、第2周的血清胰岛素浓度都明显低于模型组(P<0.05),电针组也明显高于芬太尼组(P<0.05)。芬太尼组与电针组在治疗第1周、第2周的机械痛阈都明显高于模型组(P<0.05),电针组明显高于芬太尼组(P<0.05)。芬太尼组与电针组在治疗第2周、第4周的 HDAC2蛋白表达水平明显高于模型组(P<0.05),电针组也显著高于芬太尼组(P<0.05)。结论:芬太尼联合电针在糖尿病周围神经痛大鼠的应用能提高机械痛阈,能提高大鼠体重,也可降低胰岛素浓度,其作用机制可能与促进HDAC2表达有关。  相似文献   
139.
The homologies of jaw muscles among archosaurs and other sauropsids have been unclear, confounding interpretation of adductor chamber morphology and evolution. Relevant topological patterns of muscles, nerves, and blood vessels were compared across a large sample of extant archosaurs (birds and crocodylians) and outgroups (e.g., lepidosaurs and turtles) to test the utility of positional criteria, such as the relative position of the trigeminal divisions, as predictors of jaw muscle homology. Anatomical structures were visualized using dissection, sectioning, computed tomography (CT), and vascular injection. Data gathered provide a new and robust view of jaw muscle homology and introduce the first synthesized nomenclature of sauropsid musculature using multiple lines of evidence. Despite the great divergences in cephalic morphology among birds, crocodylians, and outgroups, several key sensory nerves (e.g., n. anguli oris, n. supraorbitalis, n. caudalis) and arteries proved useful for muscle identification, and vice versa. Extant crocodylians exhibit an apomorphic neuromuscular pattern counter to the trigeminal topological paradigm: the maxillary nerve runs medial, rather than lateral to M. pseudotemporalis superficialis. Alternative hypotheses of homology necessitate less parsimonious interpretations of changes in topology. Sensory branches to the rictus, external acoustic meatus, supraorbital region, and other cephalic regions suggest conservative dermatomes among reptiles. Different avian clades exhibit shifts in some muscle positions, but maintain the plesiomorphic, diapsid soft-tissue topological pattern. Positional data suggest M. intramandibularis is merely the distal portion of M. pseudotemporalis separated by an intramuscular fibrocartilaginous sesamoid. These adductor chamber patterns indicate multiple topological criteria are necessary for interpretations of soft-tissue homology and warrant further investigation into character congruence and developmental connectivity.  相似文献   
140.
Odor and lateralization (irritation) thresholds (LTs) for ammonia vapor were measured using static and dynamic olfactometry. The purpose of the study was to explore the test-retest reliability and comparability of dynamic olfactometry methodology, generally used to determine odor thresholds following European Committee for Standardization guidelines in the context of odor regulations to outside emissions, with static olfactometry. Within a 2-week period, odor and LTs for ammonia were obtained twice for each method for 24 females. No significant differences between methods were found: mean odor detection thresholds (ODTs) were 2.6 parts per million (ppm) for either method (P = 0.96), and mean LTs were 31.7 and 60.9 ppm for the static and dynamic method, respectively (P = 0.07). Test-retest reliability was higher for the dynamic than for the static method (r = 0.61 vs. 0.14 for ODTs and r = 0.86 vs. 0.45 for LTs). The choice of optimal method for any application, however, depends not only on psychometric factors but also on practical factors such as physicochemical properties of the compound, availability of equipment and expertise, task efficiency, and costs.  相似文献   
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