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971.
为了研究β-1,4-半乳糖基转移酶 和 (β-1,4-Gal T- and )蛋白表达的亚细胞结构定位 ,本实验构建了β-1,4-Gal T- 和 融合绿色荧光蛋白 (GFP)表达质粒 ,分别将构建的质粒转染到 PC12细胞和肝癌 772 1细胞中 ,在荧光显微镜下观察β-1,4-Gal T- 和 在其中表达的亚细胞结构定位。发现 ,β-1,4-Gal T- 和 主要表达在这两种细胞的细胞核旁的 Golgi复合体 ,说明它们主要分布在 Golgi复合体上。提示它们可能是在 Golgi复合体参与蛋白质的糖链修饰 相似文献
972.
This paper describes the development of a digitized, real-time, microcomputer-based signal processing system which records the following variables: systolic and diastolic blood pressure, heart rate, pulse transit time, blood volume pulse, and R-, S-, and T-wave amplitudes of EKG signals. Forty-eight healthy subjects participated in a three-task stress response study in order to gather initial data for evaluating the reliability and validity of this monitoring system. The three tasks represented replications of earlier studies: 1) reading aloud of a monotonous neutral text (Reading Only, RO); 2) mental arithmetic without vocalization (Arithmetic Quiet, AQ); and 3) mental arithmetic with vocalization (Arithmetic Aloud, AA). The findings provided support for the reliability and validity of the new monitoring system given that few data were lost, and resting values as well as differential task responses were found to be comparable with earlier data sets derived via similar experimental protocols. 相似文献
973.
Glomerular matrix proteins in nodular glomerulosclerosis in association with light chain deposition disease and diabetes mellitus 总被引:7,自引:0,他引:7
The diagnosis of light chain deposition nephropathy is based on the immunohistochemical demonstration of monoclonal light chain deposits within connective tissue matrix and on the presence at the ultrastructural level of electron-dense granular deposits along glomerular and tubular basement membranes. A nodular glomerulopathy characterized by amorphous periodic acid-Schiff-positive and argyrophilic widened mesangium and nodules is described in three patients with light chain deposition nephropathy. Light microscopic examination did not allow discrimination between the glomerular changes found in these specimens and the nodular glomerulosclerosis described in four patients with well-documented diabetes mellitus. Electron microscopic examination revealed microtubular fibrils 10 to 12 nm thick in mesangial areas in both groups. Such microfibrils could be glycoproteins. Immunofluorescence localization of matrix proteins, by staining with affinity-purified antibodies to types I, III, IV, and V (A, B) collagens, fibronectin, laminin, and heparan sulfate-containing proteoglycans, showed similar distributions in the two conditions. The mechanism of this abnormal accumulation of mesangial and glomerular basement membrane matrix proteins in two different conditions remains unknown. 相似文献
974.
Organ spectrophotometry has been applied to analyze cytochrome redox changes in brain slice preparations. An interface-chamber method for maintaining metabolism of brain slice tissues was devised to reduce noise on recording traces of spectrophotometric signals, and then used for continuous monitoring and simultaneous recording of electrical and optical signals from brain slices. With this method, the noise level during the recording of redox states of cytochromes was decreased to 0.0004 A unit. 相似文献
975.
To identify Fc epsilon receptors on human cell lines and peripheral blood lymphocytes, we developed a new method which relies on the binding of constructed immune complexes to Fc epsilon receptor-positive cells. Cell suspensions from either cell lines or peripheral blood lymphocytes were incubated with complexes of human myeloma IgE and murine monoclonal anti-human IgE at various ratios prior to cytocentrifugation. The complexes bound to the cells were subsequently visualized by immunoperoxidase staining. The specificity of this assay to detect cell surface Fc epsilon receptors was shown by the ability of human myeloma IgE to block the binding of the IgE complexes, resulting in unstained cells, whereas IgM, IgG, and IgA were unable to block the binding of the complexes (stained cells). This method is reproducible, allows quantification of a single sample at different times, and provides a record of the results. It can also be adapted to identify any cell surface receptor for which the ligand is known. 相似文献
976.
977.
Spatial arrangements of responses by cells in the cat visual cortex to light and dark bars and edges
J. J. Kulikowski Prof. P. O. Bishop H. Kato 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1981,44(4):371-385
Summary Detailed examination is made of the responses of visual cortical cells (area 17, border 17–18 and adjacent area 18) in the anaesthetized cat to stationary flashing bars and to bars (lines) and edges moving at their optimal velocities. Particular attention is given to the receptive field organization of cells in the simple family. While there is good general agreement between the main receptive field subregions revealed by stationary and moving stimuli, the responses to moving light and dark bars, supplemented by the responses to moving light and dark edges, provide a much more rapid, accurate and complete guide to the spatial organization of the receptive fields than do the response profiles to a stationary flashing bar. Moving light and dark bars between them generally reveal more subregions in the receptive fields of simple cells than is evident from the response profiles to a stationary flashing bar, particularly when the receptive fields have many subregions. In addition the responses to moving edges provide a rapid guide to spatial summation across the width of a subregion and the possible antagonistic effects of the next subregion in sequence.Two subclasses of cells in the simple family have been recognized: ordinary simple and fast simple cells. Two cell classes (A-cells and silent periodic cells) having properties intermediate between simple and complex types are discriminated and their properties described. 相似文献
978.
S T Mason 《Physiology & behavior》1979,23(1):43-51
Male albino Wistar rats were injected bilaterally with 4 micrograms of 6-hydroxydopamine into the dorsal noradrenergic bundle to deplete forebrain noradrenaline to less than 5% of control values. Acquisition learning of a fixed interval schedule or a continuously reinforced schedule was not altered but resistance to extinction was seen after food reinforced training on either schedule but not after water reinforced training. A possible increase in food motivation was tested by the use of preloading with free food prior to a fixed interval session but both control and lesioned rats reacted similarly to this manipulation thus appearing to exclude an increase in food motivation. An attentional explanation is proposed and tested by the demonstration that resistance to extinction does not occur after a partially (variable ratio 4), as opposed to a continuously, reinforced schedule. Further evidence in favour of an attentional mechanism comes from the finding that on both a fixed interval and a continuously reinforced schedule the lesion has to be present during the acquisition phase to result in subsequent resistance to extinction. Intact animals trained on either schedule and subsequently subjected to the lesion failed to show an increased resistance to extinction. 相似文献
979.
Mixed Epithelial and Stromal Tumor of the Kidney: Preliminary Immunohistochemical and Electron Microscopic Studies of the Epithelial Component 总被引:2,自引:0,他引:2
Mixed epithelial and stromal tumor of the kidney is a rare biphasic tumor composed of cysts and tubules embedded in the spindle cell stroma. Although the histogenesis of this tumor is unknown, it has been proposed that both components of the tumor, i.e., stromal and epithelial, are neoplastic. The authors report preliminary immunohistochemical and electron microscopic studies of the epithelial component from one case of a typical, benign, mixed epithelial, and stromal tumor of the kidney. In this study, some tubules showed positivity for proximal, while others showed positivity for distal, nephron immunomarkers. By electron microscopy, some tubules had features of proximal tubular epithelium, while other tubules had features of the loop of Henle (thin segments). The authors believe that in a benign tumor such morphologic heterogeneity is inconsistent with neoplastic proliferation. Therefore, they postulate that in mixed epithelial and stromal tumor of the kidney the tubules are entrapped rather than neoplastic. Additional studies are needed to address this issue and electron microscopy should play a significant role in this process. 相似文献
980.
睡眠信念与态度量表在失眠患者健康教育中的应用 总被引:3,自引:0,他引:3
目的: 采用睡眠个人信念与态度量表探索患者睡眠障碍与哪些歪曲的信念有关,针对歪曲的信念进行睡眠实践教育,达到促进睡眠的目的.方法: 连续收集62例以失眠为主诉的患者,随机分成试验组与对照组,各31例,两组均在药物治疗及心理治疗基础上进行睡眠健康教育.试验组针对患者自身存在的歪曲信念态度进行健康教育,而对照组只进行常规的健康宣教.入组前及入组后每周,应用睡眠个人信念与态度量表(Dysfunctional Beliefs and Attitudes about Sleep Scale,DBAS)、匹茨堡睡眠指数量表(Pittsburgh Sleep Quality Index,PSQI)对两组进行测评,同时让患者评价睡眠时间、睡眠质量、睡眠效果和对健康教育接受程度.结果: 健康教育4周后试验组和对照组DBAS得分均高于人组时[(111.0±8.7)vs.(88.9±12.3)、(93.5±17.2)vs.(81.3±19.2),P:0.001、0.010],而PSQI得分均低于入组时[(5.5±2.1)vs.(10.9±4.4)、(9.0 ±2.1)vs.(11.5±3.6),均P=0.001];健康教育4周后对照组的DBAS得分低于实验组,而PSQI得分高于实验组.健康教育后试验组对睡眠时间、睡眠质量、睡眠效果满意的比例均明显提高,睡眠时间满意的比例由18/31到30/31,对睡眠质量满意比例由8/31变为23/31,对睡眠效果满意比例由8/31到21/31(均P<0.05).试验组对睡眠时间满意的比例明显高于对照组(30/31 vs.14/31,P<0.01),对健康教育的接受程度也明显高于对照组(18/31 vs.5/31,P<0.05).结论: 试验组健康教育后患者的睡眠信念有了明显的改善,睡眠质量有了提高. 相似文献