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121.
122.
The living system on earth is largely using oxygen for burning metabolic fuel for energy. The toxicity of oxygen is largely due to the formation of free radicals in living systems. Stress is also responsible for the generation of free radicals. The evidence for the involvement of free radicals and oxidative injury in producing metabolic disturbance, maladjustment and many diseases has been accumulating since long. It is largely believed that the root cause of many chronic diseases is stress induced free radicals and resultant oxidative injury. 相似文献
123.
124.
Vashist SK Kaur I Bajpai RP Bharadwaj LM Tewari R Raiteri R 《Journal of Zhejiang University. Science. B》2006,7(9):683-685
We report an important observation that the surface conductivity of antibody layer immobilized on polylysine-coated glass
substrate decreases upon the formation of complex with their specific antigens. This change in conductivity has been observed
for both monoclonal and polyclonal antibodies. The conductance of monoclonal mouse IgG immobilized on polylysine-coated glass
substrate changed from 1.02×10−8 Ω−1 to 1.41×10−11 Ω−1 at 10 V when complex is formed due to the specific biomolecular interactions with rabbit anti-mouse IgG F(ab′)2. Similar behavior was observed when the same set up was tested in two clinical assays: (1) anti-Leishmania antigen polyclonal
antibodies taken from Kala Azar positive patient serum interacting with Leishmania promastigote antigen, and (2) anti-p21
polyclonal antibodies interacting with p21 antigen. The proposed concept can represent a new immunodiagnostic technique and
may have wide ranging applications in biosensors and nanobiotechnology too. 相似文献
125.
Sanyal N Pramanik SK Pal R Chowdhury A 《Journal of Zhejiang University. Science. B》2006,7(3):202-208
Two sulfonylurea herbicides, metsulfuron methyl (Ally 20 WP) and chlorimuron ethyl (Classic 25 WP) were evaluated for their dissipation bchaviour in alluvial, coastal saline and laterite soils under laboratory incubated condition at 60% water holding capacity of soils and 30 ℃ temperature was maintained. In field study herbicides were applied twice for the control of grasses, annual and perennials broad leaves weeds and sedges in rice, wheat and soybean to find out the residual fate of both the herbicides on different matrices of respective crops after harvest. Extraction and clean up methodologies for the herbicides were standardized and subsequently analyzed by HPLC. The study revealed that the half-lives of metsulfuron methyl and chlorimuron ethyl ranged from 10.75 to 13.94 d irrespective of soils and doses applied. Field trials with rice, wheat and soybean also revealed that these two herbicides could safely be recommended for application as no residues were detected in the harvest samples. 相似文献
126.
Goswami BK Pandey RK Rathour KS Bhattacharya C Singh L 《Journal of Zhejiang University. Science. B》2006,7(11):873-875
INTRODUCTION Tomato (Lycopersicon esculentum, Mill.), an important vegetable crop is heavily attacked by root knot nematode, Meloidogyne spp. For the manage-ment of root knot nematodes although chemical nematicides were used till 1982, due to their high cost, toxic effect on beneficial soil borne microorganism and carcinogenic effect on human beings alternative approaches are practiced mainly through eco-friendly means like biological control agents, organic amendments, etc. (Singh and … 相似文献
127.
Arun Kumar B. S. Dhillon D. N. Rao Geetha Menon Hari Shankar L. K. Dhaliwal Maiti Leema Nomita Chandhiok Neeta Kumar Rohini Sehgal Suneeta Mittal Sumitu Sahdev Kandpal Shobha V. L. Jindal 《Indian journal of clinical biochemistry : IJCB》2012,27(4):405-409
Malondialdehyde (MDA) is widely used as oxidative stress biomarker in biomedical research. Plasma is stored in deep freezers generally till analysis. Effect of such storage on MDA values, which may be variable and prolong, was incidentally observed in the ongoing study which is to estimate oxidative stress with oral iron. Plasma from blood samples of pregnant women (20–30 years age) in third trimester of singleton pregnancy (n = 139), consuming oral iron tablets was stored at −20 °C with intention of MDA estimation, as soon as possible. However logistic problems led this storage for prolonged and variable period (1–708 days). When values of MDA estimated using “Ohkawa” 79 method and readings were plotted against time to check the temporal effect, it showed a hyperbolic curve. Standard deviation (SD) was lowest when samples were tested within 3 weeks time. The samples analyzed within 3 weeks had mean ± SD value of 31.59 ± 26.11 μmol/L, while 123.7 ± 93.97 and 366.5 ± 189.8 μmol/L for samples stored for 1–3 and 4 months to 1 year respectively. Mean ± SD were 539.9 ± 196.8 in the samples store for more than a year. Rate of change in values was also lowest (0.0433 μmol/L/day) in the samples tested within first 3 weeks, which rose to 1.2 μmol/L/day during 3 month’s storage. This rate peaked at storage of 120 days (1.87 μmol/L/day) and fell to 0.502 μmol/L/day in the second year of storage. It is concluded that at −20 °C, only 3 weeks of storage time should be considered valid for fairly acceptable stability in MDA values. 相似文献
128.
Sanjana Bhagat Pradeep Kumar Patra Amar Singh Thakur 《Indian journal of clinical biochemistry : IJCB》2012,27(4):394-399
This study was undertaken to determine the association of inflammatory biomarker, oxidative stress and antioxidant capacity marker with fetal haemoglobin (HbF) level among sickle cell trait and sickle cell disease (SCD) patients in Chattisgarh. The study group consisted of 51 SCD (SS) patients with painful episode, 49 SCD (SS) patients with steady state, 50 sickle cell trait (AS) and 50 controls. Malondialdehyde (MDA), CRP, total antioxidant power (FARP), total thiol and HbF levels were quantified. We found a significant positive (p < 0.0001) association between CRP and MDA levels and its inverse association with HbF level in SS patients. We also observed that antioxidant capacity had significantly positively (p < 0.0001) associated with HbF level. The protective effect of HbF was found, because the increase in HbF levels resulted in decrease in lipid peroxidation and inflammation in SCD patients. A decrease in the HbF level and its antioxidant capacity has been associated with the pathogenesis of SCD. These finding may explain the high level of HbF is ameliorating oxidative stress and inflammation in SCD patients. 相似文献
129.
Ghizal Fatima Abbas Ali Mahdi Siddharth Kumar Das Baby Anjum Nar Singh Verma Puneet Kumar Ragini Shrivastava 《Indian journal of clinical biochemistry : IJCB》2012,27(4):340-343
The present study was designed to test the hypothesis of a circadian variation in circulating levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in women with fibromyalgia syndrome (FMS). Serum levels of IL-6 and TNF-α were measured at 4 h intervals of the day in 50 women with FMS satisfying American College of Rheumatology criteria for FMS (age 36.68 ± 9.89) as well as 50 healthy control women (age 32.82 ± 10.53). Serum TNF-α levels were substantially increased in patients with FMS but showed no circadian variation. In contrast, no difference in the levels of IL-6 was found. Moreover, there was also no circadian variation in both the groups of patients and controls. We conclude that no circadian pattern exists in the circulating levels of serum IL-6 and TNF-α in patients with FMS, although TNF-α levels are found raised in patients with FMS. 相似文献
130.
The Health Sciences Library and the Department of Health Informatics & Information Management at the University of Tennessee Health Science Center in Memphis piloted an embedded librarian project in summer 2012. The value and effectiveness of the pilot project was evaluated by analyzing the content of e-mail questions received from the students and the students’ answers to the pre- and post-class surveys. The project received positive feedback from the students and course faculty. Librarians collaborating with teaching faculty and interacting one-on-one with students in health information-intensive courses proved to be helpful for student learning. 相似文献