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—A longitudinal study of the maturation of mouse cerebral lysosomal enzymes has been completed. Activity of the enzymes, acid phosphatase (I.U.B. 3.1.3.2), β-glucuronidase (I.U.B. 3.2.1.31) and β-acetylglucosaminidase (I.U.B. 3.2.1.30) was assayed spectrofluorimetrically on portions of supernatant from 0.25 M sucrose homogenates spun at 6 x 103 -min. Activities were obtained in native (free) and Triton X-100 activated samples (total). The neonatal period was characterized by relatively low free and high total acid phosphatase activities. An abrupt rise in free activity occurred during the period 10–20 days. Discontinuous anion exchange DEAE cellulose chromatography (0.01 m -tris–maleate, pH 6.3) with elution by ascending molarities of NaCl of the Triton X-100 activated supernatant revealed three major peaks in the adult. A fourth peak, designated as fraction II (‘maturation fraction’) occurred only during the neonatal period, a time also characterized by increased specific activity of fraction I, with no change in fraction IV. The chromatographic fractions were further characterized by optimal pH, ascorbate, fluoride, Cu2+ and Fe2+ ions. The maturation profiles of total, β-glucuronidase and total, β-acetylglucosaminidase differed from each other, and from that of total acid phosphatase. Comparable differences existed in the profiles of the free activities, and the ratio of free:total activity differed for each enzyme at any selected time especially during the neonatal period. These findings are are discussed with reference to the maturation of isoenzyme fractions with age, and suggest that the changes in structure-linked organization of individual lysosomal hydrolases are functions of heterogeneity in enzyme complement of individual lysosomes. 相似文献
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LYSOSOMAL ENZYMES IN NORMAL AND SCRAPIE MOUSE BRAIN 总被引:1,自引:0,他引:1
G. C. MILLSON 《Journal of neurochemistry》1965,12(6):461-468
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肠淋巴液对大鼠血压的影响 总被引:15,自引:0,他引:15
本文用引流及输入肠淋巴液的方法,研究了肠淋巴液对大鼠血压的影响。结果如下:1.经肠淋巴管插管引流肠淋巴液的大鼠,自引流后150min起,血压显著低于假手术期。2.在丢失肠淋巴液同时,补充等量白蛋白或脂肪乳,仍不能防止血压下降,但肠淋巴管-颈静脉搭桥大鼠,在4h观察过程中,血压不出现显著降低。3.重症失血性休克大鼠输入小量肠淋巴液后,血压显著回升,其血压水平及存活时间显著优于对照组。 相似文献
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Richard Rodewald 《The Journal of cell biology》1973,58(1):189-211
Evidence has been reported that the proximal small intestine of the neonatal rat selectively transports antibodies into the circulation. This study describes the morphology of the absorptive epithelial cells in this region of the intestine and their transport of several immunoglobulin tracers: ferritin-conjugated immunoglobulins (IgG-Ft) and antiperoxidase antibodies. Cells exposed to rat IgG-Ft bound the tracer on the membrane of tubular invaginations of the apical cell surface. Tubular and coated vesicles within the cell also contained the tracer, as did the intercellular spaces. Uptake of tracer was highly selective and occurred only with rat or cow IgG-Ft; when cells were exposed to chicken IgG-Ft, ferritin-conjugated bovine serum albumin, or free ferritin, tracer did not enter the cell or appear in the intercellular spaces. Experiments with rat and chicken antiperoxidase showed a similar selective uptake and transport of only the homologous antibody. When cells from the distal small intestine were exposed to the tracers, all tracers were absorbed nonselectively but none were released from the cells. Cells from the proximal small intestine of the 22-day-old rat failed to absorb even rat IgG-Ft. A model is presented for selective antibody transport in proximal cells of the neonatal rat in which antibodies are selectively absorbed at the apical cell surface by pinocytosis within tubular vesicles. The antibodies are then transferred to the intercellular space within coated vesicles. Distal cells function only to digest proteins nonselectively. 相似文献
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SUBCELLULAR DISTRIBUTION OF ENZYMES OF GLUTAMATE METABOLISM IN RAT BRAIN 总被引:11,自引:1,他引:11
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应用粘液组化技术对185例胃良恶性疾病进行了研究。结果:胃良恶性疾病伴肠化检出率无明显差异;但含有硫酸粘液的结肠型肠化在胃癌癌旁检出率明显高于良性疾病组。不同分化程度胃癌的转移及术后生存率无明显差异;但含有酸性粘液的肠型、混合型胃癌的淋巴结转移率明显较仅含中性粘液的胃型胃癌高。提示:结肠型肠化与胃癌有一定关系;癌细胞产生大量酸性粘液可能有利癌细胞的扩散与转移,对胃癌病人的预后有一定影响 相似文献
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应用免疫组织化学ABC方法等检测62 例胃良、恶性病变伴肠化组织中单克隆抗体SC3A的表达及意义。结果: 癌旁肠化硫酸粘液阳性率明显较良性病变伴肠化高; 硫酸粘液阳性组肠化SC3A阳性率明显高于硫酸粘液阴性组; 而且SC3A 阳性率在酸性粘液阳性组胃癌明显高于酸性粘液阴性组; 硫酸粘液阳性组胃癌明显高于硫酸粘液阴性组。提示结肠型肠化可能与肠型胃癌的发生有一定关系 相似文献
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双歧杆菌合剂促进急性坏死性胰腺炎肠粘膜损伤修复的实验研究 总被引:2,自引:4,他引:2
观察双歧杆菌合剂对急性坏死性胰腺炎(ANP)犬肠粘膜损伤修复的作用。经主胰管注入牛磺胆酸钠和胰蛋白酶复制犬ANP模型,观察ANP时及双歧杆菌合剂治疗后肠粘膜组织结构变化,肠组织蛋白、丙二醛(MDA)含量及肠通透性改变,检测血中内毒素(LPS)水平,脏器细菌培养。结果发现,双歧杆菌合剂治疗后,ANP犬肠粘膜损害明显减轻,肠粘膜绒毛宽度、高度和面积显著增加,肠组织蛋白含量增加,肠通透性显著下降,血中LPS水平下降1~2倍,脏器细菌易位率减少375%。结论:双歧杆菌合剂能显著促进ANP时肠粘膜损伤的修复,保护肠屏障功能,减少肠道LPS和细菌易位 相似文献
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测定结肠粘膜菌群变化对大肠癌的早期诊断辅助性的研究佳木斯医学院附属医院腔镜室佳木斯154002孙玉清佳木斯医学院生理教研室吕密凯佳木斯医学院微生物教研室李丽秋马淑霞杨景云大肠癌是常见的恶性肿瘤之一,许多资料表明发病率逐年上升。病因及发病机理不清,有关... 相似文献
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STRUCTURAL FEATURES OF THE EPITHELIO-MESENCHYMAL INTERFACE OF RAT DUODENAL MUCOSA DURING DEVELOPMENT 总被引:4,自引:6,他引:4
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In fetal rats 5–7 days before birth, the duodenal epithelium is separated from mesenchymal cells by a well-defined basal lamina. By 3–4 days before birth, when small rudimentary villi are first seen, direct contact between epithelial and mesenchymal cells occurs by means of epithelial cell cytoplasmic processes which project through gaps in the basal lamina into the lamina propria. At contact sites, the epithelial and mesenchymal cell plasma membranes were less than 100 A apart but membrane fusion was not seen. In number and size these epithelial cell processes increase strikingly during the last 2 days of gestation, and they persist in large numbers until 7–10 days after birth. Thereafter, they decrease gradually in both number and size until 3–4 wk after birth, when the morphology of the epithelio-mesenchymal interface resembles that seen in adult rats, i.e., there are only rare epithelial cell processes which penetrate deeply into the lamina propria. The presence of a large number of epithelio-mesenchymal contact sites during the period of rapid growth and differentiation of duodenal mucosa may reflect epithelio-mesenchymal cell interactions which may facilitate the maturation of the duodenal mucosa. 相似文献
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采用1-萘胺-8-磺酸(ANS)为疏水探针,对大鼠胃粘膜表面疏水性作了研究,结果表明:以ANS(25μmol/L)与胃粘膜表面刮取物(胃粘液凝胶层)混合后的萤光强度(正常为1.23±0.19RFU/胃)可代表该粘液层的疏水性;以不同浓度ANS与胃粘液混合后的萤光强度呈饱和趋势,可用Scatchard作图法求得粘液中ANS的最大萤光强度(2.467±0.638RFU/胃)和相对亲和系数(0.032±0.016),它们可分别代表胃粘液中疏水基团的总量和单个基团的疏水性,从而可阐明胃粘膜被盐酸损伤后凝胶层粘液的ANS萤光减弱,系其疏水基团总量减少,而非单个基团的疏水性改变所致。 相似文献
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—Dexamethasone administration to newborn rats resulted in an increase in phenylethanolamine N-methyltransferase activity in superior cervical ganglia. The same treatment resulted in a decrease in tyrosine hydroxylase and choline acetyltransferase activities. The decline in choline acetyltransferase activity after dexamethasone treatment was only seen when the drug was given before 5 days of age. When dexamethasone was given to pregnant rats it caused an age-dependent decrease in choline acetyltransferase in the adrenals, superior cervical ganglia and para-aortic chromaffin tissue of the offspring. These results suggest that dexamethasone administration may delay the development of the preganglionic neurons of sympathetic ganglia. This in turn would delay the development of tyrosine hydroxylase but not phenylethanolamine N-methyltransferase. 相似文献
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研究以草鱼(Ctenopharyngodon idellus)为实验对象, 运用厌氧培养的方法, 研究了饥饿状态下草鱼肠道黏膜固有微生物的类群及其在不同肠段的分布。实验结果显示草鱼前肠、中肠与后肠中细菌的数量分别是3.17×103、1.63×104和1.79×107 cfu/g。研究共分离到274株单菌落, 经16S rRNA鉴定, 分别属于拟杆菌属(Bacteroides spp.)、鲸杆菌属(Cetobacterium spp.)、梭形杆菌属(Fusobacterium spp.)、气单胞菌属(Aeromonas spp.)、希瓦氏菌属(Shewanella spp.)、芽孢杆菌属(Bacillus spp.)、泛菌属(Pantoea spp.)和柠檬酸杆菌属(Citrobacter spp.)8个种类, 其中专性厌氧细菌的数量占9.1%, 兼性厌氧细菌的数量占90.9%。进一步分析发现, 前肠中只分离到兼性厌氧细菌, 中肠与后肠专性厌氧细菌和兼性厌氧细菌都有分布。专性厌氧细菌Bacteroides paurosaccharolyticus和Bacteroides luti在中肠与后肠都有分布, 而Cetobacterium somerae和Fusobacterium ulcerans只在后肠有发现。兼性厌氧细菌是草鱼肠道黏膜的优势菌群, 其中嗜水气单胞菌Aeromonas hydrophila占73.7%。草鱼肠道不同部位固有厌氧微生物组成存在差异, 细菌数量也明显不同, 后肠中具有更高的细菌丰度和多样性。 相似文献
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—Activities of acid phosphatase, alkaline phosphatase and β-glucuronidase have been estimated in the brain tissues, using various subcellular particles, in growing thyroidectomized rats and also using cytoplasmic extracts free from debris and nuclear fraction in young hypothyroid animals. Hepatic glucose-6-phosphate dehydrogenase activity was markedly reduced after thyroidectomy but the enzyme was brought back to normal levels by thyroxine treatment. There was no change, however, in the activity of neural glucose-6-phosphate dehydrogenase after thyroidectomy. In the thyroidectomized animals an increase only in the free acid phosphatase activity in the neural synaptosomes was found and this increase in activity was not counteracted by administration of thyroxine. In the hypothyroid young animal β-glucuronidase, acid phosphatase and alkaline phosphatase activities were found to be affected during development. 相似文献
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应用AB(pH1.0)KOH/PAS粘液组织化学和ABC法凝集素标记,对190例胃粘膜病变标本进行观察。结果表明,结肠不完全型肠上皮化生多见于肠型癌(ITC)及其癌旁组织。两型肠化在弥漫型癌(DTC)中无显著差异。5种凝集素受体的含量和分布的差异与胃癌的组织学类型和分化程度有关。WGA、RCA和PNA主要标记在DTC中,与ITC相比,有非常显著的差异(P<0.01)。其染色水平随肿瘤分化程度的降低而升高。ConA和DBA主要标记在ITC和伴有肠化的慢性萎缩性胃炎中。凝集素肠化分型与粘液肠化分型基本相符。我们认为结肠不完全肠化与ITC的发生关系密切,而小肠型和结肠完全型肠化可能与DTC的发生有关。 相似文献
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Abstract— The enzymes catalysing ethanol metabolism, alcohol dehydrogenase (EC 1.l.1.1) and aldehyde dehydrogenase (EC 1.2.1.3), were assayed in a variety of neural and somatic tissues of the rat, the human counterparts of which are known to be vulnerable to excessive ethanol. The activity of alcohol dehydrogenase was assayed by the coupled oxidation of ethanol and reduction of lactaldehyde, a method which we have recently found to be sufficiently sensitive and specific to measure the relatively low levels of activity in whole brain. Detectable activities of these enzymes were found in peripheral nerve, skeletal muscle, retina, optic nerve and various regions of brain, as well as in a variety of non-neural tissues. The levels of the enzymic activities in all tissues were markedly lower than those of liver, but probably sufficient to perform a local function in the metabolism of ethanol or other endogenous substrates. The activity of alcohol dehydrogenase in the various tissues, like that of liver, was confined to the cytosol and exhibited kinetic properties and responses to inhibitors almost identical to those of the liver enzyme. We consider the results to be consistent with the hypothesis that the pathological effects of alcohol may be related, at least in part, to local mechanisms for the metabolism of alcohol. 相似文献
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J. M. Saavedra M. Palkovits J. S. Kizer M. Brownstein J. A. Zivin 《Journal of neurochemistry》1975,25(3):257-260
Abstract— Biogenic amines and related enzymes were quantitatively measured in the pituitary gland of the rat. The sensitivity of the assays used allows the determinations to be performed in single pituitary lobes. Relatively high values of histamine and serotonin were found in all three lobes, with higher amounts in the posterior and intermediate lobes. Highest catecholamine concentrations were detected in the posterior lobe, and only very low amounts of dopamine were measured in the anterior lobe. Throughout the gland, norepinephrine concentrations were low, about one-tenth that of dopamine. Tryptamine could not be detected. High levels of A and B monoamine oxidase were found in all three pituitary lobes. Tyrosine hydroxylase activity was measured in the posterior and intermediate lobes, but was not detected in the anterior lobe. Tryptophan hydroxylase was present in all three pituitary lobes. A relatively low catechol- O -methyltransferase activity was found in the anterior lobe, and none was detected in the intermediate and posterior lobe. Choline acetyltransferase, dopamine-β-hydroxylase and phenylethanolamine- N -methyltransferase activities could not be detected. 相似文献
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新生大鼠小肠上皮细胞分离培养研究 总被引:8,自引:2,他引:8
本实验比较了4种分离大鼠IEC的方法,结果显示联合应用粗胶原酶和中性蛋白酶分离效果最好,细胞贴壁生长能力强。胶原涂膜改善玻璃培养瓶或盖玻片表面的性状有利于细胞贴壁生长。细胞的增殖依赖于培养液的质量、成分及细胞间的相互作用。培养细胞一般1~2天贴壁,7~8天明显增殖,10~14天汇合成片。培养细胞细胞角质蛋白、碱性磷酸酶染色阳性,光镜和电镜检查均显示为IEC。本文所建立的新生大鼠IEC体外培养方法为研究IEC生理和病理提供了一个十分有用的实验模型。 相似文献
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EFFECTS OF PUROMYCIN ON THE STRUCTURE OF RAT INTESTINAL EPITHELIAL CELLS DURING FAT ABSORPTION 总被引:2,自引:2,他引:2
This report provides information on the morphology of rat intestinal epithelial cells during fat absorption. In addition, the role of protein metabolism in this process has been evaluated by blocking its synthesis with puromycin and studying the fine structure of mucosal cells from rats at various times after fat intubation. The results indicate that SER-derived vesicles, containing fat droplets, migrate from the apical cytoplasm of the absorptive cell and fuse with saccules or vacuoles of the Golgi complex. Arguments are made that the Golgi complex is important in completing chylomicron formation and in providing appropriate enveloping membranes for the chylomicron. Such membranes may be necessary for Golgi vacuoles to fuse with the lateral cell membranes and release chylomicra. Puromycin treatment causes the absorptive cell to accumulate increased quantities of lipid that are devoid of membrane during fat absorption. In addition, puromycin-treated cells contain much less RER and Golgi membranes are strikingly decreased in number. In this paper we discuss the consequences of these abnormalities and suggest that continued protein synthesis by the RER is required in order to generate Golgi membranes. If such membranes are absent the cell's ability to discarge chylomicra is impaired and lipid accumulates. 相似文献