首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   43篇
  免费   3篇
  国内免费   1篇
  2022年   1篇
  2021年   9篇
  2020年   5篇
  2019年   2篇
  2018年   1篇
  2017年   1篇
  2016年   3篇
  2015年   5篇
  2013年   5篇
  2012年   2篇
  2011年   3篇
  2010年   1篇
  2009年   2篇
  2008年   2篇
  2007年   1篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  1994年   1篇
排序方式: 共有47条查询结果,搜索用时 468 毫秒
1.
The Protein Journal - As a safe substitute for hydroquinone, β-arbutin, a natural plant substance, and its synthetic counterpart, α-arbutin, are used in depigmentation formulations....  相似文献   
2.

Colorectal cancer (CRC) is known as the most common form of malignancies in the world and its occurrence is annually increasing. Due to the relatively high death rates in patients, finding better diagnostic and prognostic factors are required. Substance P (SP) belongs to the tachykinin family that acts as an immunomodulator by binding to the neurokinin-1 receptor (NK1R). The interaction of SP with NK1R might be involved in tumor cell proliferation, angiogenesis, and migration. Hence, this study was aimed to evaluate the serum SP level and tissue distribution of NK1Rs in CRC. Also, we assessed the relationship between tissue distribution of NK1R and some different tumor characteristics, including tumor size, and lymph node status. Recruiting 38 patients primarily diagnosed with CRC, the tissue distribution of NK1R was immunohistochemically evaluated in tumor tissues and their adjacent normal tissue. The serum level of SP was measured using an ELISA method in both cases and healthy control group. The SP value was significantly increased in the serum of patients in comparison with the healthy group (p?=?0.001). Tumor tissues expressed a higher number of NK1R than adjacent normal tissues (p?=?0.01) considering both the percentage of stained cells and intensity of staining. However, there was not any statistically significant relevance between NK1R distribution and tumor characteristics. The SP/NK1R system is involved in tumorigenesis of CRC, and might be suggested as a potent prognostic or diagnostic factor, or a new target in the treatment of CRC.

  相似文献   
3.
3-Hydroxybutyrate, one of the main blood ketone bodies, has been considered as a critical indicator for diagnosis of diabetic ketoacidosis. Biosensors designed for detection of 3-hydroxybutyrate with advantages of precision, easiness and speedy performance have attracted increasing attention. This study attempted to develop a 3-hydroxybutyrate dehydrogenase-based biosensor in which single-walled carbon nanotubes (SWCNT) was used in order to immobilize the cofactor, NAD+, on the surface of screen-printed electrode. The formation of NAD+–SWCNT conjugates was assessed by electrochemistry and electron microscopy. Cyclic voltammetry was used to analyze the performance of this biosensor electrochemically. The considerable shelf life and reliability of the proposed biosensor to analyze real sample was confirmed by this method. The reduction in the over potential of electrochemical oxidation of NADH to ?0.15 V can be mentioned as a prominent feature of this biosensor. This biosensor can detect 3-hydroxybutyrate in the linear range of 0.01–0.1 mM with the low detection limit of 0.009 mM. Simultaneous application of screen-printed electrode and SWCNT has made the biosensor distinguished which can open new prospects for detection of other clinically significant metabolites.  相似文献   
4.
Epidermal growth factor receptor (EGFR) is deemed to be one of the main molecular targets for diagnosis and treatment of cancer. It has been identified that EGFR involves in pathogenesis of some forms of human cancers. Monoclonal antibodies targeting EGFR could control the tumor cell growth, proliferation, and apoptosis by suppressing the signal transduction pathways. Nanobodies can be regarded as the smallest intact antigen binding fragments, derived from heavy chain-only antibodies existing in camelids. Here, we describe the identification of an EGFR-specific nanobody, referred to as OA-cb6, obtained from immunized camel with a cell line expressing high levels of EGFR. Utilizing flow cytometry (FACS) and blotting methods, we demonstrated that OA-cb6 nanobody binds specifically to EGFR expressing on the surface of A431 cells. In addition, OA-cb6 nanobody potently causes the inhibition of EGFR over expression, cell growth and proliferation. The antibody fragments can probably be regarded as worthwhile binding block for further rational design of anti-cancer therapy.  相似文献   
5.
Cheese whey fermentation to ethanol using immobilized Kluyveromyces marxianus cells was investigated in batch and continuous operation. In batch fermentation, the yeast cells were immobilized in carboxymethyl cellulose (CMC) polymer and also synthesized graft copolymer of CMC with N-vinyl-2-pyrrolidone, denoted as CMC-g-PVP, and the efficiency of the two developed cell entrapped beads for lactose fermentation to ethanol was examined. The yeast cells immobilized in CMC-g-PVP performed slightly better than CMC with ethanol production yields of 0.52 and 0.49 g ethanol/g lactose, respectively. The effect of supplementation of cheese whey with lactose (42, 70, 100 and 150 g/l) on fermentative performance of K. marxianus immobilized in CMC beads was considered and the results were used for kinetic studies. The first order reaction model was suitable to describe the kinetics of substrate utilization and modified Gompertz model was quite successful to predict the ethanol production. For continuous ethanol fermentation, a packed-bed immobilized cell reactor (ICR) was operated at several hydraulic retention times; HRTs of 11, 15 and 30 h. At the HRT of 30 h, the ethanol production yield using CMC beads was 0.49 g/g which implies that 91.07 % of the theoretical yield was achieved.  相似文献   
6.
Cellulose nanocrystal grafted with chitosan oligosaccharide (CNC-CSOS) was used to encapsulate vitamin C and prepare CNCS/VC complexes using tripolyphosphte via ionic complexation. The stability of vitamin C and the antioxidant activity of the CNCS/VC complexes were elucidated. The formation of the complex was confirmed using DSC and UV–vis spectrophotometry, and TEM was used to study the morphology of the complexes. The encapsulation efficiency of vitamin C at pH 3 and 5 was 71.6% ± 6.8 and 91.0 ± 1.0, respectively. Strong exothermic peaks observed in isothermal titration calorimetric (ITC) studies at pH 5 could be attributed to additional electrostatic interactions between CNC-CSOS and vitamin C at pH 5. The in vitro release of vitamin C from CNCS/VC complexes showed a sustained release of up to 20 days. The vitamin C released from CNCS/VC complex displayed higher stability compared with the control vitamin C solution, and this was also confirmed from the ITC thermograms. CNC-CSOS possessed a higher scavenging activity and faster antioxidant activity compared with its precursors, i.e., oxidized CNC and CSOS and their physical mixtures. Complexing vitamin C into CNC-CSOS particles yielded a dynamic antioxidant agent, where the vitamin C is released over time and displayed sustained antioxidant properties. Therefore, CNCS/VC can potentially be used in cosmeceutical applications as topical formulations.KEY WORDS: cellulose nanocrystals, chitosan oligosaccharide, controlled release, vitamin C antioxidant activity  相似文献   
7.
Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disease, affecting phagocytic blood cells, which predispose patients to recurrent infectious complications. Herein, an 11-year-old girl is described who presented with liver abscess at the age of 9 years. Positive dihydrorhodamine (DHR) and nitrobluetetrazolium (NBT) tests confirmed the diagnosis of CGD for the patient. Anti-tuberculosis drugs and parenteral antibiotic therapy were started. Unusual visceral abscess and recurrent infections should be considered as an alarm for primary immunodeficiency diseases, while early diagnosis and appropriate treatment could prevent severe complications and even death in this group of patients.  相似文献   
8.
Antibody titers to several heat shock proteins (anti-Hsps) have been reported to be associated with the severity and progression of cardiovascular disease. However, there are little data regarding anti-Hsp27 titers in patients with coronary artery disease (CAD). A total of 400 patients with suspected CAD were recruited. Based on the results of coronary angiography, these patients were classified into CAD+ (n = 300) and CAD (n = 100) groups defined as patients with ≥50% and <50% stenosis of any major coronary artery, respectively. Eighty-three healthy subjects were also recruited as the control group. Serum anti-Hsp27 IgG titers were measured using an in-house enzyme-linked immunosorbent assay. CAD+ patients had significantly higher anti-Hsp27 titers compared with both CAD and control groups. Anti-Hsp27 titers were also higher in the CAD group compared with the control group. With regard to the number of affected vessels in the CAD+ group, patients with three-vessel disease had higher anti-Hsp27 titers compared with both two-vessel disease (2VD) and one-vessel disease (1VD) subgroups. However, there was no significant difference between 1VD and 2VD subgroups. In multiple linear regression analysis, the number of narrowed vessels and smoking were significant independent determinants of serum anti-Hsp27 titers. The present findings indicate that serum anti-Hsp27 titers may be associated with the presence and severity of coronary artery disease.  相似文献   
9.
Bioprocess and Biosystems Engineering - Cultivation of microalgae in wastewater is a promising and cost-effective approach for both CO2 biofixation and wastewater remediation. In this study, a new...  相似文献   
10.
A novel design of gold-coated iron oxide nanoparticles was fabricated as a potential delivery system to improve the efficiency and stability of d, l-sulforaphane as an anticancer drug. To this purpose, the surface of gold-coated iron oxide nanoparticles was modified for sulforaphane delivery via furnishing its surface with thiolated polyethylene glycol-folic acid and thiolated polyethylene glycol-FITC. The synthesized nanoparticles were characterized by different techniques such as FTIR, energy dispersive X-ray spectroscopy, UV-visible spectroscopy, scanning and transmission electron microscopy. The average diameters of the synthesized nanoparticles before and after sulforaphane loading were obtained ∼ 33 nm and ∼ 38 nm, respectively, when ∼ 2.8 mmol/g of sulforaphane was loaded. The result of cell viability assay which was confirmed by apoptosis assay on the human breast cancer cells (MCF-7 line) as a model of in vitro-cancerous cells, proved that the bare nanoparticles showed little inherent cytotoxicity, whereas the sulforaphane-loaded nanoparticles were cytotoxic. The expression rate of the anti-apoptotic genes (bcl-2 and bcl-xL), and the pro-apoptotic genes (bax and bak) were quantified, and it was found that the expression rate of bcl-2 and bcl-xL genes significantly were decreased when MCF-7 cells were incubated by sulforaphane-loaded nanoparticles. The sulforaphane-loaded into the designed gold-coated iron oxide nanoparticles, acceptably induced apoptosis in MCF-7 cells.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号