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21.
22.
Beltrão EI Correia MT Figueredo-Silva J Coelho LC 《Applied biochemistry and biotechnology》1998,74(3):125-134
The phenomenon of altered carbohydrates in transformed cell surfaces has been studied through histochemical techniques using
lectins. Specific binding patterns to normal and transformed mammary tissues were evaluated by Isoform 1 fromCratylia mollis lectin (Cra Iso 1). Protocols using a direct method, incubation of Cra Iso I conjugated to peroxidase (Cra Iso 1-Per) with
mammary tissues, followed by diaminobenzidine and hydrogen peroxidase interaction, were performed. Neoplastic tissues, marked
by Cra Iso 1, showed a higher intensity of staining than normal ones, in comparison withCanavalia ensiformis lectin, Concanavalin A (Con A), conjugated to peroxidase (Con A-Per). The assay with Cra Iso 1 also indicated a possible
utilization of this lectin to characterize normal and transformed mammary cells. 相似文献
23.
测定了116例冠心病患者血清中钙、镁、镉、铅、铍的含量并与正常对照组比较。结果显示,常量元素钙、镁与微量元素镉、铅含量降低,而铍的含量升高。它们之间的差异有显著性或高度显著性,P〈0.05或P〈0.01。 相似文献
24.
用计算机多元分析研究冠心病微量元素谱,识别冠心病患者与健康者;非线性映射法判别率男性86.6%,女性96.2%;SIMCA差别法正确回判率男性85.0%,女性88.3%。 相似文献
25.
Wolfgang Benetka Manfred Koranda Frank Eisenhaber 《Monatshefte für Chemie / Chemical Monthly》2006,137(10):1241-1281
Summary. Since 1979, when prenylation has been first discovered as chemical oddity of a yeast mating factor, the two forms of this
posttranslational modification of proteins (farnesylation and geranylgeranylation) have been found as wide spread among proteins
from Eukarya and their viruses. This review attempts to summarize as comprehensively as possible the enzymological processes
of prenylation and the various aspects of their biological significance.
The substrate proteins of prenyltransferases are known to carry a sequence signal composed of a cysteine-containing 4–5 residue
stretch at the utmost C-terminal end that is N-terminally preceded by a flexible and polar linker region of ca. 10 residues. Postprenylation processing of substrate proteins can involve C-terminal proteolysis, C-terminal carboxyl methylation,
and other steps of maturation. The prenyl anchor functions as module for membrane attachment or for protein–protein interaction.
Prenyl anchor carrying proteins fulfill a large array of functions in signaling and regulation of cellular processes. Therefore,
they are involved in the pathogenesis of a variety of human diseases, the most prominent one being cancer. Farnesyltransferase
inhibitors show surprisingly high efficiency in controlling tumor growth in model systems but, so far, clinical trials with
human patients have remained without the desired success. Interference into prenylation pathways appears also a promising
treatment principle in a variety of parasitic diseases. 相似文献
26.
《Arabian Journal of Chemistry》2022,15(9):103970
Ethnopharmacological relevanceMetabolic syndrome is closely related to the intestinal microbiota and disturbances in the host metabolome. Hyperuricemia (HUA), a manifestation of metabolic syndrome, can induce various cardiovascular diseases and gout, seriously affecting a patient’s quality of life. Astragalus membranaceus has a long history as a commonly used traditional Chinese medicine to treat kidney disease in China and East Asia.Materials and methodsWe compared the therapeutic effect of benzbromarone and two different doses Astragalus membranaceus ultrafine powder (AMUP) in rats with HUA. Ultra-performance liquid chromatography-mass spectrometer was used to analyze the AMUP metabolism in the plasma, urine, and feces. Further, 16S ribosome RNA sequencing and feces metabolomic were performed to capture the variation of the gut microbiota and metabolites changes before and after drug administration.ResultsAMUP had a notable impact on reducing blood uric acid levels while protecting the liver and kidney. Drug metabolism analysis demonstrated that effective constituent flavonoids are distributed in the blood, whereas saponins remain in the intestine. Gut microbiota analysis showed that low-dose AMUP ameliorated HUA-induced gut dysbiosis by reducing the abundance of harmful bacteria and increasing that of some beneficial bacteria with anti-inflammatory properties, such as Clostridia, Lachnospiraceae, and Muribaculaceae. In addition, HUA-induced changes in metabolite contents in bile acid and adrenal hormone biosynthesis pathways were restored after treatment with AMUP.ConclusionLow-dose AMUP exerts remarkable therapeutic effects on HUA by regulating the gut microbiome and mediating gut metabolism pathways associated with uric acid excretion. 相似文献
27.
As a prelude to development of a human vaccine against Lyme disease, the first chemical synthesis of glycolipid antigens of Borrelia burkholderi is reported. First, cholesteryl β-d-galactopyranoside was synthesized and was converted to partially protected congeners having the HO-6 group of the galactose moiety unprotected. Treatment of these intermediates with palmitic and oleic acid, respectively, under dehydrative conditions followed by removal of the protecting groups afforded cholesteryl 6-O-palmitoyl/oleoyl-β-d-galactopyranosides that were identical to the glycolipids isolated from B. burkholderi. 相似文献
28.
本文对CT联合血清同型半胱氨酸(HCY)、β2-微球蛋白(β2-M)在下肢动脉狭窄闭塞性疾病中的诊断价值进行分析。选取上海市金山区中西医结合医院收治的120例疑似下肢动脉狭窄闭塞性疾病患者进行研究,选取同期健康体检者120例作为对照组,对患者进行CT检查、血清HCY和β2-M水平检查,并比较了CT诊断下肢动脉狭窄闭塞情况、两组患者血清HCY和β2-M水平,以明确CT、HCY、β2-M诊断价值及误诊率、漏诊率。结果显示,120例疑似患者中,CT检测出646节段病变血管,其中轻度狭窄155节段,中度狭窄257节段,重度狭窄143节段,血管完全闭塞91节段;研究组患者血清HCY、β2-M水平明显高于对照组,两组比较差异有统计学意义(P<0.05);HCY的AUC为0.863,截断值>21.75(μmol/L),诊断敏感性为79.00%,特异性为80.00%,β2-M的AUC为0.837,截断值>2.98(μmol/mL),诊断敏感性为75.25%,特异性为65.21%;CT诊断阳性率为67.50%,HCY诊断阳性率为69.17%,β2-M诊断阳性率为67.50%,三者联合诊断阳性率为82.50%,联合诊断阳性率高于CT、HCY、β2-M单独诊断阳性率(P<0.05);CT、HCY、β2-M单一检测对下肢动脉狭窄闭塞性疾病均有较高灵敏度、特异性及准确度,但三者联合诊断灵敏度、特异性及准确度最高,误诊率、漏诊率最低。本文证实了采用CT联合血清HCY、β2-M诊断下肢动脉狭窄闭塞性疾病诊断灵敏度、特异性及准确度高,误诊率、漏诊率低。 相似文献
29.
《Arabian Journal of Chemistry》2022,15(4):103707
Alsophila spinulosa is a tree-like fern, and many evidences suggested that plant polyphenols had the potential therapeutic for Alzheimer s disease (AD). Herein, polyphenols (ASP) was isolated from A. spinulosa leaves and its major constituent were isoorientin and vitexin. ASP displayed excellent antioxidant activity and obvious anti-lipid peroxidation capacity in vitro. ASP improved the survival rate of C. elegans under high temperature by enhancing the antioxidant enzymes activities and decreasing the lipid peroxidation level. Moreover, ASP alleviated β-amyloid (Aβ) induced paralysis and reduced Aβ deposition, decreased reactive oxygen species (ROS) accumulation and improved the level of skn-1 mRNA. In addition, ASP decreased the levels of pdk-1 and akt-1 mRNA in P13K/AKT signaling pathway. In conclusion, ASP may be a potential ingredient for the alleviation of AD. 相似文献
30.
116例冠心病患者血清中铜铬锰钴镍钒含量的探讨 总被引:1,自引:0,他引:1
测定了116例冠心病患者血清中铜、铬、锰、钴、镍、钒的含量并与正常值比较,显示含量升高才是有铬和镍,降低者有钴和钒、无差异者有铜和锰。 相似文献