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1.
Clonal cell lines possessing parathyroid hormone-stimulated adenylate cyclase were established from a rat osteosarcoma. These lines have retained undiminished hormone responsiveness through more than 5 months in continuous culture. Both the extent stimulation and hormone sensitivity were similar to those found in freshly excised tumor and embryonic bone.  相似文献   
2.
EcoHealth - Increasing reports of marine mammal deaths have been attributed to the parasite Sarcocystis neurona. Infected opossums, the only known definitive hosts, shed S. neurona sporocysts in...  相似文献   
3.
Free radicals are implicated in many diseases including atherosclerosis, cancer and also in rheumatoid arthritis. Reaction of uric acid with free radicals, such as hydroxyl radical and hypochlorous acid (HOCl) results in allantoin production. In this study, we measured the serum allantoin levels, oxidation products of uric acid, as a marker of free radical generation in rheumatoid arthritis. Fasting blood samples were obtained from 21 rheumatoid patients and 15 healthy controls. In this study, the serum allantoin and uric acid levels were measured by a gas chromatography–mass spectrometry method and the ratios were calculated. The mean allantoin and uric acid levels and ratios in the patient group were 22.1±11.3, 280.5±65.0 and 8.0±3.7?μM, while in the control group they were 13.6±6.3, 278.3±53.6 and 4.9±2.1?μM, respectively. The effects of gender, age, menopausal status, duration of disease and medications on serum allantoin and uric acid levels of the patient and control groups were studied. Our results suggest that uric acid acts as a free radical scavenger and thus is converted to allantoin. Increased allantoin levels suggest the possible involvement of free radicals in rheumatoid arthritis.  相似文献   
4.
Methylene blue (MB) biosorption properties of Rhizopus arrhizus were investigated in the presence of surfactants. The effects of cationic and anionic surfactants on MB removal by dead biomass (1 g L?1) were determined. MB removal was tested as a function of initial pH (2–12), contact time (5–1440 min), and dye (37.4–944.7 mg L?1) and surfactant (0–10 mM) concentrations. The opposite charged anionic surfactant dodecylbenzenesulfonic acid sodium salt (DBS) enhanced sorption of cationic MB by biomass dramatically. Maximum biosorption capacity was 471.5 mg g?1 at pH 8 with 0.5 mM DBS at 944.7 mg L?1 MB concentration. The surfactant-stimulated fungal decolorization method may provide a highly efficient, inexpensive, and time-saving procedure in biological wastewater treatment technologies.  相似文献   
5.
Protein tyrosine kinases (PTKs) play an important role in T cell development and activation. In vitro and in vivo defects, resulting in variable deficiencies in thymic development and in T cell antigen receptor (TCR) signal transduction, in PTKs have been shown. ZAP70, one of those PTKs, is a 70-kDa tyrosine phosphoprotein and associates with the ζ chain and undergoes tyrosine phosphorylation following TCR stimulation. It is expressed in T and natural killer (NK) cells. Several mutations were shown to lead to an autosomal recessive form of severe combined immunodeficiency disease (SCID).  相似文献   
6.
Objective:This study aims to investigate the effect of 8-week whole-body vibration (WBV) added to conventional training on muscular architecture, dynamic muscle strength and physical performance compared to controls in young basketball players.Methods:Sixteen young basketball players between the ages of 14-16 years were randomly assigned to whole body vibration group (VG) or control group (CG). Both groups were trained with a conventional program. Pennation angle (PeA), fascicle length and muscle thickness of Rectus Femoris (RF) and Vastus lateralis were measured by ultrasonography. Isokinetic dynamic muscle testing at 180 °/s and 60°/s, squat jump (SJ) and flexibility were evaluated before and after 8 weeks of training programs. Primary outcome measure was the fascicle length.Results:Fascicle length of RF, SJ height and flexibility increased significantly within VG compared to pretraining (p<0.05). SJ height increased in VG compared to CG significantly following training (p<0.05). PeA, fascicle length, muscle thicknesses, strength and flexibility did not differ between groups.Conclusion:Eight weeks of WBV training improved fascicle length of RF, SJ height, and flexibility compared to pre-training. Addition of WBV to conventional training did not cause improvement in muscle architecture, strength and flexibility compared to conventional training alone.  相似文献   
7.
Propolis is a multi-functional bee product rich in polyphenols. In this study, the inhibitory effect of Anatolian propolis against SARS-coronavirus-2 (SARS-CoV-2) was investigated in vitro and in silico. Raw and commercial propolis samples were used, and both samples were found to be rich in caffeic acid, p-coumaric acid, ferulic acid, t-cinnamic acid, hesperetin, chrysin, pinocembrin, and caffeic acid phenethyl ester (CAPE) at HPLC-UV analysis. Ethanolic propolis extracts (EPE) were used in the ELISA screening test against the spike S1 protein (SARS-CoV-2): ACE-2 interaction for in vitro study. The binding energy values of these polyphenols to the SARS-CoV-2 spike and ACE-2 protein were calculated separately with a molecular docking study using the AutoDock 4.2.6 program. In addition, the pharmacokinetics and drug-likeness properties of these eight polyphenols were calculated according to the SwissADME tool. The binding energy value of pinocembrin was highest in both receptors, followed by chrysin, CAPE, and hesperetin. Based on the in silico modeling and ADME (absorption, distribution, metabolism, and excretion) behaviors of the eight polyphenols, the compounds exhibited the potential ability to act effectively as novel drugs. The findings of both studies showed that propolis has a high inhibitory potential against the Covid-19 virus. However, further studies are now needed.  相似文献   
8.
Various molecular and cellular processes are involved in renal fibrosis, such as oxidative stress, inflammation, endothelial cell injury, and apoptosis. Heat shock proteins (HSPs) are implicated in the progression of chronic kidney disease (CKD). Our aim was to evaluate changes in urine and serum HSP levels over time and their relationships with the clinical parameters of CKD in children. In total, 117 children with CKD and 56 healthy children were examined. The CKD group was followed up prospectively for 24 months. Serum and urine HSP27, HSP40, HSP47, HSP60, HSP70, HSP72, and HSP90 levels and serum anti-HSP60 and anti-HSP70 levels were measured by ELISA at baseline, 12 months, and 24 months. The urine levels of all HSPs and the serum levels of HSP40, HSP47, HSP60, HSP70, anti-HSP60, and anti-HSP70 were higher at baseline in the CKD group than in the control group. Over the months, serum HSP47 and HSP60 levels steadily decreased, whereas HSP90 and anti-HSP60 levels steadily increased. Urine HSP levels were elevated in children with CKD; however, with the exception of HSP90, they decreased over time. In conclusion, our study demonstrates that CKD progression is a complicated process that involves HSPs, but they do not predict CKD progression. The protective role of HSPs against CKD may weaken over time, and HSP90 may have a detrimental effect on the disease course.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-021-01239-9.  相似文献   
9.
Two novel series of small-molecule RGD mimetics containing either a substituted pyridone or pyrazinone central constraint were prepared. Modification of the beta-alanine 3-substituent produced compounds that are potent and selective alpha(v)beta(3) antagonists and exhibit a range of physicochemical properties.  相似文献   
10.
The purpose of this study was to investigate the anti-hyaluronidase activities of honeys from different botanical origins honeys in order to determine their anti-inflammatory properties. The total phenolic contents, total flavonoids and total tannin levels of six types of honey, chestnut, oak, heather, pine, buckwheat and mixed blossom, were determined. Concentration-related inhibition values were tested turbidimetrically on bovine testis hyaluronidase (BTHase) as IC50 (mg/mL). All honeys exhibited various concentration-dependent degrees of inhibition against BTHase. Inhibition values varied significantly depending on honeys’ levels of phenolic contents, flavonoid and tannin. The honeys with the highest anti-hyaluronidase activity were oak, chestnut and heather. In conclusion, polyphenol-rich honeys have high anti-hyaluronidase activity, and these honeys have high protective and complementary potential against hyaluronidase-induced anti-inflammatory failures.  相似文献   
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