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排序方式: 共有265条查询结果,搜索用时 15 毫秒
21.
Haik Kristi L.; Shear Deborah A.; Hargrove Chad; Patton Jared; Mazei-Robison Michelle; Sandstrom Michael I.; Dunbar Gary L. 《Canadian Metallurgical Quarterly》2008,16(2):178
Parkinson's disease (PD) is a neurodegenerative disorder in which loss of dopaminergic (DA) neurons (>50%) in the substantia nigra (SN) precedes most of the overt motor symptoms, making early diagnosis and treatment interventions difficult. Because PD has been associated with free radicals generated by nitric oxide, this study tested whether treatments of 7-nitroindazole (7NI), a nitric-oxide-synthase inhibitor, could reduce cognitive deficits that often emerge before overt motor symptoms in a presymptomatic rat model of PD. Rats were given intraperitoneal injections of 50 mg/kg 7NI (or vehicle) just before receiving bilateral, intrastriatal injections of the DA-toxin, 6-hydroxydopamine (6-OHDA). The rats were then given a battery of motor tasks, and their learning ability was assessed using a spatial reversal task in a water-T maze. Results indicate that 7NI treatments attenuate 6-OHDA-induced spatial learning deficits and protect against DA cell loss in the SN, suggesting that 7NI may have potential as an early, presymptomatic pharmacotherapy for PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
This paper describes a simple and efficient method for the immmunohistochemical processing of tissue sections on glass slides and the subsequent transfer of the entire section to an Araldite® medium. These sections present in one plane can then be orientated and when cut provide the user with whole tissue, free from gaps due to folding. This procedure therefore enables the changes in protein concentration and distribution to be assessed and correlated within and between different cells at the light and electron microscopic level. This procedure may be of use in other microscopic techniques studies. 相似文献
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24.
Neuronal activation was examined by fos immunohistochemistry in ring doves (Streptopelia risoria) reunited with their young after overnight separation. In an initial study, squab-exposed parents showed more fos immunoreactivity (ir) in the preoptic area (POA) and lateral hypothalamus (LH) than squab-deprived parents. In a 2nd study, parents allowed free access to young and those separated from young by a wire mesh partition showed more fos-ir in the POA, LH, and lateral septum than box-exposed controls. Contact with young also increased fos-ir in the medial preoptic nucleus and bed nucleus of the stria terminalis, but noncontact exposure did not. Conversely, nontactile squab exposure stimulated more fos-ir in the POA than did free access to young, which suggests POA involvement in appetitive aspects of parenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
本研究对15例小脑髓母细胞瘤外科切除标本作了超微结构和10种抗体(P53,PCNA,NF,NSE,GFAP,S-100,Vi,LCA,CK,NF)免疫组化观察,描述了典型髓母细胞瘤和促纤维增生型髓母细胞斩一般形态,超微结构和免疫组化特点。发现:超微结构和免疫组化均支持瘤细胞主要朝向神经细胞分化,同时有残存的胶质细胞及有髓纤维。,PCNA在15例肿瘤中100%阳性表达,阳性细胞百分率更高,平均39. 相似文献
26.
S. RAY T. EL KHASSAWNA U. SOMMER U. THORMANN N.D. WIJEKOON K. LIPS C. HEISS V. ALT 《Journal of microscopy》2017,265(1):111-120
Wnt/β‐catenin signalling components was shown to affect bone cells function including chondrocytes.Secreted Dkk1, a potent osteogenesis inhibiting factor mediates bone loss in diseased bones by suppressing the biological actions of Wnt proteins. In addition, increased Dkk1 signalling inhibits chondrogenesis in new bone formation. Recent findings also show there exists a cross‐talk between the chondrocytes and the cells of the osteoblast lineage, which are the most affected cell types in muskuloskeletal disorders. This study investigated whether spatial expression of Dkk1 is confined to only osteoblasts, osteocytes or chondrocytes. The second objective was to detect a difference in the Dkk1 expression pattern in healthy subjects when compared to pathological state. To elucidate the cell specificity of Dickkopf‐1 (Dkk1) in healthy bones, samples from female Sprague–Dawley rats were tested against two different antibodies with the two most widely accepted visualization system (ABC and Envision). The findings show Dkk1 specificity predominantly for osteoblasts, chondrocytes and osteocytes depending upon the antibody used. In addition, Dkk1 expression was evaluated in different cells of human osteoarthritis (OA) and rheumatoid arthritis (OA) patients. Its overexpression in pathologic state also suggests the role of Dkk1 in bone formation. This is scientifically and clinically important in studying the effect of Dkk1 in bone healing and in designing treatments for patients with compromised bone status. Taking into consideration the paradigm that cartilage and subchondral bone behave as an interconnected functional unit, normalization of cell behaviour in one compartment may have benefits in both tissues. 相似文献
27.
Acrylic resin mixtures are commonly used to study microscopic sections of biological specimens, giving the advantage of good morphological preservation. Existing embedding protocols, however, are suitable for tissue blocks, not exceeding 1 mm in thickness. We have developed a protocol to embed larger specimens (up to 2 cm(3)) in Technovit 8100. This medium allowed us to perform classic histological (trichrome), silver, as well as immunohistochemical staining, needed for multi-signal detection at high-resolution imaging to reconstruct a three-dimensional interpretation of a serially sectioned muscle. The technique was applied to reconstruct the semitendinosus muscle of a fetal pig, 44 days post conception, featuring connective tissue, intramuscular nerves, blood vessels, and muscle fibre types. For the reconstruction, a technique was used that enabled us to insert high-resolution images of histological details into low-resolution images of the entire muscle. 相似文献
28.
Arcamone N Lucini C Borzacchiello G Castaldo L Gargiulo G De Girolamo P 《Microscopy research and technique》2005,66(1):17-24
By means of immunochemistry and immunohistochemistry, we investigated in the kidney of freshwater and marine teleostean species for the presence and localization of three neurotrophins: nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin (NT)-3. In both species studied, NGF-like and NT-3-like immunoreactivity were present in the kidney with different distribution patterns, while BDNF-like immunoreactivity was never detected. In goldfish, NGF-like and NT-3-like immunoreactivity were identified extensively in cells along part of the arterial branches adjacent to the afferent arterioles. In scorpion fish, NGF-like and NT-3-like immunoreactive cells were observed both on afferent arterioles and on adjacent secondary branches derived from renal arteries. No immunoreactivity was detected in other renal structures. A staining pattern of immunoreactivity similar to that obtained for NGF and NT-3 was detected utilizing S100 antibody as a juxtaglomerular (JG) cell marker. Double immunolabellings NGF/S100 and NT-3/S100 evidenced the coexistence of neurotrophin-like proteins and S100-like protein in the same immunoreactive cells, thus identifying them as juxtaglomerular cells. Western blot analysis revealed the presence of molecules immunoreactive to NGF and NT-3, whose molecular weights were very similar to those of the corresponding mammalian neurotrophins. These findings extend the presence and distribution of NGF-like and NT-3-like IR in the kidney to teleost species, suggesting a probable participation of these proteins in the renal functions of freshwater and marine teleosts. 相似文献
29.
目的观察不良应激因素对小鼠人卵巢癌移植瘤dicer酶的表达影响。方法将人卵巢癌组织采用背部皮下接种法移植裸鼠,建立人卵巢癌细胞裸鼠皮下移植瘤模型。成功造模后,取体质量及肿瘤大小相近的裸鼠按随机数字表法分为对照组和应激组,每组6只。对照组裸鼠自由供水和食物;应激组裸鼠采用束缚方法给予应激,束缚应激时将应激组裸鼠依次放入打孔通风的50 mL离心管,每天束缚6 h,5 d.周-1,束缚期间禁水、禁食,完成束缚应激后将裸鼠放出,恢复自由供水和食物,应激时间共2周。观察2组裸鼠生存状态、体质量及皮下移植瘤体积;完成应激后处死裸鼠,取皮下人卵巢癌组织,采用RT-PCR和免疫组织化学染色,比较2组人卵巢癌组织中dicer酶的表达水平。结果应激组裸鼠摄食及活动不佳,与对照组相比,应激组裸鼠体质量明显下降(P〈0.05);2组比较,肿瘤体积差异无统计学意义(P〉0.05);RT-PCR和免疫组织化学染色结果表明:与对照组相比,应激组裸鼠卵巢癌组织中dicer酶的表达量明显下降(P〈0.05)。结论不良心理应激因素能降低人卵巢癌移植瘤中dicer酶的表达。dicer酶的表达可成为研究不良心理应激对肿瘤生长影响的重要参考指标。 相似文献
30.
探讨Ezrin表达及超声引导下穿刺活检对肝细胞癌(HCC)的应用价值,实验方法如下:36例经超声引导下穿刺所得的HCC组织作肝穿癌组;45例手术切除的HCC组织作手术癌组,同时取12个癌旁肝组织作癌旁组;用免疫组化方法检测两组标本的Ezrin蛋白表达,并与临床病理学参数做统计学分析。得出结果:肝穿癌组Ezrin阳性表达... 相似文献