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51.
大鼠肝内移植肿瘤与肥大细胞关系的形态学研究   总被引:3,自引:0,他引:3  
目的:研究大鼠肝内移植肿瘤与其周边肥大细胞的关系。方法:建立40只雄性Wistar大鼠肝内移植肿瘤模型,运用HE染色,肥大细胞(mast cell,MC)Alcian blue特殊染色,苦味酸-天狼猩红染色和电镜等技术,观察移植肿瘤肝组织的形态学改变,肿瘤周边浸润MC的数量以及MC与肿瘤组织的关系,8只正常大鼠为对照组。结果:肿瘤组织周边部分肝细胞形态学异常;肝组织内胶原纤维增生,主要为Ⅰ型和Ⅲ型胶原,并包绕肿瘤组织,肿瘤周边MC浸润,并沿胶原纤维分布,不同大鼠其肿瘤周边MC数量不一,有的差异明显。超微结构观察显示MC通过多个接触点与肿瘤细胞紧密相连,并释放胞质颗粒内容物,导致肿瘤细胞崩解。结论:MC与肿瘤组织有着非常密切的关系,MC可能通过多种途径直接和间接地发挥抗肿瘤作用。  相似文献   
52.
Qin C  Wang J  Wei Q  She M  Marasco WA  Jiang H  Tu X  Zhu H  Ren L  Gao H  Guo L  Huang L  Yang R  Cong Z  Guo L  Wang Y  Liu Y  Sun Y  Duan S  Qu J  Chen L  Tong W  Ruan L  Liu P  Zhang H  Zhang J  Zhang H  Liu D  Liu Q  Hong T  He W 《The Journal of pathology》2005,206(3):251-259
A new SARS animal model was established by inoculating SARS coronavirus (SARS-CoV) into rhesus macaques (Macaca mulatta) through the nasal cavity. Pathological pulmonary changes were successively detected on days 5-60 after virus inoculation. All eight animals showed a transient fever 2-3 days after inoculation. Immunological, molecular biological, and pathological studies support the establishment of this SARS animal model. Firstly, SARS-CoV-specific IgGs were detected in the sera of macaques from 11 to 60 days after inoculation. Secondly, SARS-CoV RNA could be detected in pharyngeal swab samples using nested RT-PCR in all infected animals from 5 days after virus inoculation. Finally, histopathological changes of interstitial pneumonia were found in the lungs during the 60 days after viral inoculation: these changes were less marked at later time points, indicating that an active healing process together with resolution of an acute inflammatory response was taking place in these animals. This animal model should provide insight into the mechanisms of SARS-CoV-related pulmonary disease and greatly facilitate the development of vaccines and therapeutics against SARS.  相似文献   
53.
In order to investigate the role of monocyte/macrophages and their relationship to the expression of macrophage colony-stimulating factor (MCSF) in pulmonary atherosclerosis, lungs were excised from rabbits that had been fed for 60 and 90 days on a diet containing 0.5% cholesterol. In the lungs, fatty streaks and elevated foam cell lesions predominated in the large or medium-sized elastic pulmonary arteries, while massive accumulation of foam cells in the intima of muscular arteries produced marked luminal narrowing and nearly complete occlusion. In these lesions, most of the foam cells were reactive with RbM2, a monoclonal antibody (mAb) against rabbit macrophages, while smooth muscle cell-derived foam cells were detected by mAb against smooth muscle actin in the deeper area of elevated foam cell lesions of elastic arteries. Ultrastructural observation confirmed the presence of monocytes in the intima, their differentiation into macrophages, and their transformation into foam cells in the atherosclerotic lesions. lmmunohistochemical expression of MCSF was demonstrated in the endothelial cells, smooth muscle cells and foam cells. A minor macrophagederived foam cell population was demonstrated to possess a prolif-erative capacity. These data suggest that MCSF is involved in the differentiation of monocytes into macrophages, their transformation into foam cells, and their proliferation during pulmonary atherogenesis.  相似文献   
54.
Zhu DM  Wang M  She JQ  Yu K  Ruan DY 《Neuroscience》2005,134(1):215-224
Previous studies have demonstrated that synaptic plasticity, which includes long-term potentiation (LTP) and depotentiation (DP) in hippocampus, is important for learning and memory. The purpose of this study is to evaluate the effect of taurine via drinking water on the lead-induced impairments of LTP and DP in rat dentate gyrus (DG) in vivo. The experiments were carried out in four groups of rats (control, lead-exposed, control and lead-exposed with a taurine-supplement diet, respectively). The input-output (I/O) function, excitatory postsynaptic potential (EPSP) and population spike (PS) amplitude were measured in the DG area of adult rats (60-90 days) in response to stimulation applied to the lateral perforant path. The results show that: 1. chronic lead exposure impaired LTP/DP measured on both EPSP slope and PS amplitude in DG area of the hippocampus; 2. in control rats, taurine had no effect on LTP/DP; 3. the amplitudes of LTP/DP of lead-exposed group were significantly increased by applying taurine. These results suggest that dietary taurine supplement could protect rats from the lead-induced impairments of synaptic plasticity and might be a preventive medicine to cure the cognitive deficits induced by lead.  相似文献   
55.
The aim of this study was to examine the effect of age on left ventricular (LV) systolic function in normal healthy adults. Eighty consecutive subjects without cardiovascular disease underwent standard and tissue Doppler (TD) echocardiographic imaging. LV systolic function was assessed by load-dependent indices as ejection fraction (EF) and myocardial systolic velocities by TD as well as by the load-independent index, systolic isovolumic acceleration rate (IVA). None of the echocardiographic measurements of systolic function declined with age (mean IVA for the group, 286 +/- 123 cm s(-2); IVA vs. age, r = 0.21, P = 0.1). Likewise, LV end diastolic dimension, wall thickness, mass and left atrial maximum volume were not significantly related to age. On the other hand, as previously reported, echocardiographic indices of diastolic function showed a significant decline with age (P < 0.05). When the group was stratified by gender, isovolumic velocity and acceleration were higher in men than women, but the differences were not significant (P = 0.12 and 0.37, respectively). No significant relation was observed between age and measurements of LV systolic function by regression analysis in women (P > 0.1). However, in men, a positive correlation was noted between average IVA and age (r = 0.63, P = 0.007). In conclusion, age is not associated with a change in cardiac structure and LV systolic function, but is accompanied by a decline in echocardiographic indices of diastolic function. With respect to gender, age does not appear to influence LV systolic function in women, but is associated with an increase in IVA and septal systolic ejection in men.  相似文献   
56.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
57.
为研究金丝桃的抗脂质过氧化作用,用分光光度法测定了金丝桃提取物对大鼠离体组织匀浆的脂质过氧化及由Fe2+-H2O2体系、Fe2+-VitC体系和Fe2+-Cys体系诱导的脂质过氧化的抑制作用。发现金丝桃提取物对大鼠肝、心、肾组织匀浆脂质过氧化和线粒体诱导的脂质过氧化具有抑制作用并表现出剂量依赖关系,而且提取物F003的抑制作用要强于F004、F005的抑制作用。认为金丝桃具有较好的抗脂质过氧化作用,具有进一步研究与开发价值。  相似文献   
58.
This study was to explore the effect and mechanism of Probucol on STZ-induced erectile dysfunction in diabetic rats. Thirty SD male rats aged 12 weeks were given intraperitoneal injection of STZ after fasting for 12 hr. Diabetic rats were haphazardly partitioned under two assemblies and administered 0 or 500 mg/kg probucol by oral gavage to 12 weeks. Control group was intraperitoneally injected with physiological saline, and saline was administered by oral gavage daily. Intracorporeal pressure was used to evaluate erectile function. Levels of proteins were detected using immunohistochemistry and Western blotting. α-SMA and vWF were detected using immunofluorescence staining. After treatment, erectile function in probucol group was significantly improved. Endoplasmic reticulum stress-related proteins were expressed higher in DM group than in sham group, while expression of these proteins decreased significantly in probucol group. However, α-SMA and vWF were expressed at lower levels in DM group than in sham group, and probucol treatment reversed this phenomenon. Finally, Bax and Caspase3 were expressed at higher levels and Bcl-2 was expressed at lower levels in DM group, while the opposite result was obtained in probucol group. In conclusions, probucol improves erectile function by reducing endothelial dysfunction and inhibiting PERK/ATF4/CHOP pathway in STZ-induced diabetic rats.  相似文献   
59.
目的探讨瞬时感受器电位离子通道香草素受体4(TRPV4)在睾丸缺血再灌注损伤(IRI)中对GC-1细胞增殖和凋亡的作用及其机制。方法建立睾丸GC-1细胞缺氧复氧模型,采用蛋白质印迹法(Western blot)检测不同复氧损伤时间点TRPV4的表达变化;分别采用噻唑蓝(MTT)实验、流式细胞术检测转染TRPV4对GC-1细胞增殖和凋亡的影响;采用Western blot法检测睾丸组织中转染TRPV4对GC-1细胞中半胱氨酰天冬氨酸特异性蛋白酶(Caspase)-3和细胞色素C(Cyt-C)表达的影响,组间比较采用t检验,多组间比较采用单因素方差分析。结果对照组及缺氧复氧组(0、6、12、24、48和72 h)TRPV4的蛋白表达水平分别为0.19±0.02、0.35±0.03、0.42±0.04、0.46±0.04、0.62±0.05、0.54±0.05、0.45±0.04。缺氧复氧组TRPV4表达显著高于未缺氧GC-1细胞的对照组,并在复氧24 h达到峰值(F=6.898,P<0.05),差异有统计学意义;缺氧复氧组中细胞增殖水平明显低于对照组(52.32±4.58比100.00±7.63,t=-9.280,P<0.05),差异有统计学意义,细胞凋亡水平高于对照组(15.60±1.72比4.08±0.87,t=10.352,P<0.05),差异有统计学意义;过表达TRPV4组中细胞增殖水平低于其对照组(23.65±3.98比51.35±4.67,t=-7.820,P<0.05),差异有统计学意义,细胞凋亡水平高于其对照组(26.93±2.15比14.62±1.68),t=7.814,P<0.05),差异有统计学意义;沉默TRPV4组中细胞增殖水平高于其对照组(72.49±6.21比53.18±5.14,t=4.150,P<0.05),差异有统计学意义,细胞凋亡水平低于其对照组(9.71±1.25比15.07±1.64,t=-4.502,P<0.05),差异有统计学意义。缺氧复氧组中Caspase-3和Cyt-C表达水平高于对照组(0.70±0.06比0.20±0.02,t=13.693,P<0.05;0.74±0.07比0.26±0.03,t=10.917,P<0.05),差异有统计学意义;过表达TRPV4组中Caspase-3和Cyt-C表达水平高于其对照组(1.25±0.11比0.69±0.07,t=7.439,P<0.05;1.38±0.14比0.72±0.07,t=7.303,P<0.05),差异有统计学意义;沉默TRPV4组中Caspase-3和Cyt-C表达水平低于其对照组(0.46±0.05比0.68±0.06,t=-4.879,P<0.05;0.45±0.05比0.72±0.06,t=-5.988,P<0.05),差异有统计学意义。结论TRPV4在GC-1细胞中高表达,其可能通过改变GC-1细胞的增殖和凋亡能力,从而影响睾丸IRI的发生发展。  相似文献   
60.
The relevance of Tregs in the induction of tolerance against corneal allografts has been well established. Although it is well known that the conversion of Tregs into effector-like cells contributes to the loss of corneal immune privilege, the underlying mechanism is still not fully understood. Using heterologous penetrating keratoplasty model, we found that Tregs from corneal allograft rejected mice (inflam-Tregs) exhibit impaired function and characteristics of effector T cells. Further study showed that the expression of NF-κB c-Rel, a key mediator of effector T cell function, was significantly increased in inflam-Tregs. Mechanistic study revealed that elevated NF-κB c-Rel level in inflam-Tregs impaired Treg function through the promotion of inflammatory cytokine production and glycolysis. More importantly, we demonstrated that targeting NF-κB c-Rel was able to improve the immune suppressive function of inflam-Tregs in vitro and enhance the potential of them to suppress corneal transplantation rejection. Therefore, our current study identified NF-κB c-Rel as a key mediator of the conversion of Tregs into effector-like cells when under inflammatory environment.  相似文献   
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