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931.
Pathological and biochemical consequences of acute and chronic neuroinflammation within the basal forebrain cholinergic system of rats 总被引：4，自引：0，他引：4
Inflammatory processes may play a critical role in the degeneration of basal forebrain cholinergic cells that underlies some of the cognitive impairments associated with Alzheimer's disease. In the present study, the proinflammagen lipopolysaccharide, from the cell wall of Gram-negative bacteria, was used to produce inflammation within the basal forebrain of rats. The effects of acute, high-dose injections of lipopolysaccharide (2, 20 or 40 microg) upon basal forebrain chemistry and neuronal integrity were compared with the effects of chronic, low-dose lipopolysaccharide infusions (0.18, 0.25, 1.8 or 5.0 microg/h) for either 14, 37, 74 or 112 days. Acute exposure to lipopolysaccharide decreased cortical choline acetyltransferase activity and the number of immunoreactive choline acetyltransferase-positive cells within a small region of the basal forebrain. Regional levels of five different neuropeptides were unchanged by acute, high-dose lipopolysaccharide injections. Chronic lipopolysaccharide infusions produced (i) a time-dependent, but not dose-dependent, decrease in cortical choline acetyltransferase activity that paralleled a decline in the number of choline acetyltransferase- and p75-immunoreactive cells within the basal forebrain, and (ii) a dense distribution of reactive astrocytes and microglia within the basal forebrain. Chronic neuroinflammation might underlie the genesis of some neuropathological changes associated with normal ageing or Alzheimer's disease. 相似文献
932.
近年来,随着经济的迅速发展,人们生活方式、水平的改善,糖尿病发病率呈急剧上升趋势,经流行病学调查,60%-75%的糖尿病患者都伴有抑郁症状,甚至其中10%-35%的患者为重度抑郁,而抑郁患者的糖尿病发病风险是正常人的2倍。糖尿病罹患抑郁症（DD）严重影响患者生活质量,已经引起越来越多的关注。目前治疗DD的药物以化学药物为主,由于其靶点单一、药物依赖性强、副作用明显等原因,故寻找多靶点、低毒、副作用小的治疗药物,是临床亟待解决的棘手问题。课题组研究发现益气养血方当归补血汤（DBD）对DD有较为确切的疗效,现对其研究现状加以综述。 相似文献
933.
血管内皮细胞增生是胃癌相关性病变 总被引：16，自引：7，他引：9
目的观察胃癌间质组织中血管内皮细胞(EC)早期病变,探讨血管EC增生性改变在肿瘤发生、发展过程中作用.方法利用手术切除胃癌组织和化学诱发大鼠胃癌,观察血管结构特征并用抗人和抗鼠免疫组化进行标记.结果肿瘤间带血管EC明显增生,约占血管总数的60%,这些增生的血管EC,有的形成腺样结构,有的异形和癌变.结论胃癌间质血管EC的病理性改变,是肿瘤发生、发展的重要因素,抗人Ⅷ因子和抗鼠VEGF阳性也说明血管EC增生是肿瘤相关性病变. 相似文献
934.
Li JP Feng GL Li DQ Wang HB Zhao DL Wan Y Jiang HJ 《Hepatobiliary & pancreatic diseases international : HBPD INT》2016,15(6):612-618
BACKGROUND: Functional imaging such as CT perfusion can detect morphological and hemodynamic changes in he-patocellular carcinoma (HCC). Pre-carcinoma and early HCC nodules are dififcult to differentiate by observing only their hemodynamics changes. The present study aimed to investi-gate hemodynamic parameters and evaluate their differential diagnostic cut-off between pre-carcinoma and early HCC nod-ules using CT perfusion and receiver operating characteristic (ROC) curves.
METHODS: Male Wistar rats were randomly divided into con-trol (n=20) and experimental (n=70) groups. Diethylnitrosa-mine (DEN) was used to induce pre-carcinoma and early HCC nodules in the experimental group. Perfusion scanning was carried out on all survival rats discontinuously from 8 to 16 weeks. Hepatic portal perfusion (HPP), hepatic arterial frac-tion (HAF), hepatic arterial perfusion (HAP), hepatic blood volume (HBV), hepatic blood lfow (HBF), mean transit time (MTT) and permeability of capillary vessel surface (PS) data were provided by mathematical deconvolution model. The perfusion parameters were compared among the three groups of rats (control, pre-carcinoma and early HCC groups) using the Kruskal-Wallis test and analyzed with ROC curves. Histo-logical examination of the liver tissues with hematoxylin and eosin staining was performed after CT scan.
RESULTS: For HPP, HAF, HBV, HBF and MTT, there were signiifcant differences among the three groups (P<0.05). HAF had the highest areas under the ROC curves: 0.80 (control vs pre-carcinoma groups) and 0.95 (control vs early HCC groups) with corresponding optimal cut-offs of 0.37 and 0.42, respectively. The areas under the ROC curves for HPP was 0.79 (control vs pre-carcinoma groups) and 0.92 (control vs early HCC groups) with corresponding optimal cut-offs of 136.60 mL/min/100 mg and 108.47 mL/min/100 mg, respectively.
CONCLUSIONS: CT perfusion combined with ROC curve analysis is a new diagnosis model for distinguishing between pre-carcinoma and early HCC nodules. HAF and HPP are the ideal reference indices. 相似文献
METHODS: Male Wistar rats were randomly divided into con-trol (n=20) and experimental (n=70) groups. Diethylnitrosa-mine (DEN) was used to induce pre-carcinoma and early HCC nodules in the experimental group. Perfusion scanning was carried out on all survival rats discontinuously from 8 to 16 weeks. Hepatic portal perfusion (HPP), hepatic arterial frac-tion (HAF), hepatic arterial perfusion (HAP), hepatic blood volume (HBV), hepatic blood lfow (HBF), mean transit time (MTT) and permeability of capillary vessel surface (PS) data were provided by mathematical deconvolution model. The perfusion parameters were compared among the three groups of rats (control, pre-carcinoma and early HCC groups) using the Kruskal-Wallis test and analyzed with ROC curves. Histo-logical examination of the liver tissues with hematoxylin and eosin staining was performed after CT scan.
RESULTS: For HPP, HAF, HBV, HBF and MTT, there were signiifcant differences among the three groups (P<0.05). HAF had the highest areas under the ROC curves: 0.80 (control vs pre-carcinoma groups) and 0.95 (control vs early HCC groups) with corresponding optimal cut-offs of 0.37 and 0.42, respectively. The areas under the ROC curves for HPP was 0.79 (control vs pre-carcinoma groups) and 0.92 (control vs early HCC groups) with corresponding optimal cut-offs of 136.60 mL/min/100 mg and 108.47 mL/min/100 mg, respectively.
CONCLUSIONS: CT perfusion combined with ROC curve analysis is a new diagnosis model for distinguishing between pre-carcinoma and early HCC nodules. HAF and HPP are the ideal reference indices. 相似文献
935.
936.
Xiaoyan Zhang Zhan‐Qiu Liu Dara Singh Gregory J. Wehner David K. Powell Kenneth S. Campbell Brandon K. Fornwalt Jonathan F. Wenk 《NMR in biomedicine》2017,30(8)
Rat models have assumed an increasingly important role in cardiac research. However, a detailed profile of regional cardiac mechanics, such as strains and torsion, is lacking for rats. We hypothesized that healthy rat left ventricles (LVs) exhibit regional differences in cardiac mechanics, which are part of normal function. In this study, images of the LV were obtained with 3D cine displacement encoding with stimulated echoes (DENSE) cardiovascular magnetic resonance in 10 healthy rats. To evaluate regional cardiac mechanics, the LV was divided into basal, mid‐ventricular, and apical regions. The myocardium at the mid‐LV was further partitioned into four wall segments (i.e. septal, inferior, lateral, and anterior) and three transmural layers (i.e. sub‐endocardium, mid‐myocardium, and sub‐epicardium). The six Lagrangian strain components (i.e. Err, Ecc, Ell, Ecl, Erl, and Ecr) were computed from the 3D displacement field and averaged within each region of interest. Torsion was quantified using the circumferential‐longitudinal shear angle. While peak systolic Ecl differed between the mid‐ventricle and apex, the other five components of peak systolic strain were similar across the base, mid‐ventricle, and apex. In the mid‐LV myocardium, Ecc decreased gradually from the sub‐endocardial to the sub‐epicardial layer. Ell demonstrated significant differences between the four wall segments, with the largest magnitude in the inferior segment. Err was uniform among the four wall segments. Ecl varied along the transmural direction and among wall segments, whereas Erl differed only among the wall segments. Erc was not associated with significant variations. Torsion also varied along the transmural direction and among wall segments. These results provide fundamental insights into the regional contractile function of healthy rat hearts, and form the foundation for future studies on regional changes induced by disease or treatments. 相似文献
937.