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1.
Objective: A natural cyclic peptide previously isolated from Citrus medica was synthesized by coupling oftetrapep-tide units Boc-Leu-Pro-Trp-Leu-Ome and Boc-Ile-Ala-Ala-Gly-Ome after proper deprotection at carboxyl and amino terminals followed by cyclization of linear octapeptide segment.Methods: Solution phase technique was adopted for the synthesis of cyclooctapeptide--sarcodactylamide.Required tetrapeptide units were prepared by coupling of Boc-protected dipeptides viz.Boc-Leu-Pro-OH and Boc-Ile-Ala-OH with respective dipeptide methyl esters Trp-Leu-Ome and Ala-Gly-Ome.Cyclization of linear octapeptide unit was done by p-nitrophenyl ester method.The structure of synthesized cyclopolypeptide was elucidated by FTIR,1H NMR,13C NMR,FABMS spectral data and elemental analysis.The newly synthesized peptide was evaluated for dif-ferent pharmacological activities including antimicrobial,anthelmintic and cytotoxic activities.Results: Synthesis of sarcodac-tylamide was accomplished with >78% yield utilizing dicyclohexylcarbodiimide (DCC) as coupling agent.Newly synthesized peptide possessed potent cytotoxic activity against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines,in addition to moderate anthelmintic activity against earthworms Megascoplex konkanensis,Pontoscotex corethruses and Eudrilus sp.Moreover,cyclopolypeptide displayed good antimicrobial activity against pathogenic fungi Candida albicans and Gram-negative bacteria Pseudomonas aeruginosa,in comparison to standard drugs griseofulvin and ciprofloxacin.Conclusion: Solution phase technique employing DCC and triethylamine (TEA) as base proved to be effective for the synthesis of natural cyclooctapeptide.N-methyl morpholine (NMM) was found to be a better base for the cyclization of linear octapeptide unit in comparison to TEA and pyridine. 相似文献
2.
Since accurate decisions are required for effective management, much research has focused on information systems that support decision making. Recently, this research has engendered frameworks, such as the management support system (MSS), that are designed to provide comprehensive and integrated support for the decision making process. Few, if any, studies have empirically measured the effects of these frameworks on decision making. This article offers empirical evidence on MSS effectiveness. It overviews the decision making process, presents an MSS for supporting the process, and assesses the influences of the MSS on the process and outcomes of health care decision making. The paper also examines the implications of the analyses for information systems research and health care practice. 相似文献
3.
N. Khanna A. Garg K. K. Sharma R. Khosla 《Indian journal of clinical biochemistry : IJCB》1997,12(1):86-90
In the present study which was aimed to see the effect of zinc on pentylenetetrazole induced convulsive threshold in rats we found that zinc sulfate 100 μg intracerebroventricularly) and pentylenetetrazole (50 mg/kg intraperitoneally) produced dose related seizure activity; however, pretreatment with zinc decreased the threshold, increased the severity, incidence of multiple seizures and total duration of pentylenetetrazole induced seizures. Diazepam (5 mg/kg intraperitoneally) pretreatment increased the threshold and lowered the incidence of convulsions in zinc induced seizures which further confirms that the convulsive effect of zinc is through inhibition of gamma aimino butyric acid. 相似文献
4.
A. K. Pradhan A. K. Shukla M. V. R. Reddy N. Garg 《Indian journal of clinical biochemistry : IJCB》2004,19(1):83-87
Oxidative stress was assesed by estimating lipid peroxidation product (LPO) in the form of thiobarbituric acid reactive substances
(TBARS), enzymatic antioxidants in the form of superoxide dismutase (SOD), catalase and nonenzymatic antioxidant vitamins
e.g. vitamin C, β carotene and vitamin E in either serum or plasma or erythrocytes in 190 cases of age related cataract in
the age group of 50–80 years. 190 cases were grouped into three morphological types namely, 73 cases of cortical, 77 cases
of posterior subcapsular and 40 cases of nuclear cataract and values of LPO and antioxidants were compared with 78 cases of
age matched healthy control groups. Plasma TBARS levels were cataract cases when compared with control groups. There were
no significant differences in the erythrocyte levels of catalase and plasma levels of Vit E between cataract cases and control
groups. No significant changes of parameters were seen among three different morphological types of age related cataract.
The present study shows that the oxidative stress may play an important role in the age related cataract. 相似文献
5.
We present evidence on productivity improvement experienced by the research institutes of the Chinese Academy of Sciences (CAS) after its implementation of the Knowledge Innovation Program (KIP). Using a balanced panel of data on R&D inputs and outputs of 59 research institutes in CAS, we analyze the productivity, technological and efficiency changes from 1997 to 2005. We document that the CAS research institutes have a productivity growth of 12.5% from 1998 to 2005, which can be further decomposed into 8.8% attributed to technological progress and 3.3% to efficiency improvement. Results of regional analysis show that institutes in Beijing and Shanghai, performed better than institutes in other regions during the same period. 相似文献
6.
Teaching Multistep Equations with Virtual Manipulatives to Secondary Students with Learning Disabilities 
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下载免费PDF全文 Rajiv Satsangi Rachel Hammer Anya S. Evmenova 《Learning disabilities research & practice》2018,33(2):99-111
Students with learning disabilities often struggle with the academic demands presented in secondary mathematics curricula. To combat these students’ struggles, researchers have studied various pedagogical practices and classroom technologies for teaching standards covered in subjects such as algebra and geometry. However, as the role of computer‐ and tablet‐based technologies in education grows, some areas of study, such as the use of virtual manipulatives, lack exploration. This study sought to assess the benefits of virtual manipulatives to teach secondary students with a learning disability in mathematics how to solve multistep algebraic equations. A multiple baseline design across three participants demonstrated a functional relation between the use of a virtual manipulative balance and teaching students to acquire, maintain, and generalize the skill of solving multistep algebraic equations. Results provide new evidence demonstrating virtual manipulatives as a beneficial age‐appropriate technology to teach higher order mathematical concepts to secondary students with a learning disability. 相似文献
7.
P. Chandran N. K. Kuchhal P. Garg C. S. Pundir 《Indian journal of clinical biochemistry : IJCB》2007,22(2):145-150
Chemical composition of gall stones is essential for aetiopathogensis of gallstone disease. We have reported quantitative
chemical analysis of total cholesterol bilirubin, calcium, iron and inorganic phosphate in 120 gallstones from haryana. To
extend this chemical analysis of gall stones by studying more cases and by analyzing more chemical constituents. A quantitative
chemical analysis of total cholesterol, total bilirubin, fatty acids, triglycerides, phospholipids, bile acids, soluble proteins,
sodium potassium, magnesium, copper, oxalate and chlorides of biliary calculi (52 cholesterol, 76 mixed and 72 pigment) retrieved
from surgical operation of 200 patients from Haryana state was carried out. Total cholesterol as the major component and total
bilirubin, phospholipids, triglycerides, bile acids, fatty acids (esterified), soluble protein, calcium, magnesium, iron,
copper, sodium, potassium, inorganic phosphate, oxalate and chloride as minor components were found in all types of calculi.
The cholesterol stones had higher content of total cholesterol, phospholipids, fatty acids (esterified), inorganic phosphate
and copper compared to mixed and pigment stones. The mixed stones had higher content of iron and triglycerides than to cholesterol
and pigment stones. The pigment stones were richer in total bilirubin, bile acids, calcium, oxalate, magnesium, sodium, potassium,
chloride and soluble protein compared to cholesterol and mixed stones. Although total cholesterol was a major component of
cholesterol, mixed and pigment gall stone in Haryana, the content of most of the other lipids, cations and anions was different
in different gall stones indicating their different mechanism of formation. 相似文献
8.
Lotka's law and institutional productivity 总被引：1，自引：0，他引：1
The present study aims at determining the applicability of Lotka's law, negative binomial distribution and lognormal distribution for institutional productivity, in the same way as it is to authors and their productivity in the field of engineering sciences and the patents filed by industrial firms in laser S&T. The study indicates that non of the three distributions are applicable for institutional productivity in engineering sciences. However, Lotka's law holds good for full as well as truncated set of data for the patents filed by industrial firms. 相似文献
9.
H. R. Mali S. A. Siddiqui Madhur Garg R. K. Singh M. L. B. Bhatt 《Indian journal of clinical biochemistry : IJCB》1998,13(1):36-40
Present study repots changes in serum copper levels (SCL) in various neoplastic diseases undergoing radiotherapy. We estimated
SCLs in 140 individuals comprising of 90 previously untreated patients with various malignancies and 50 healthy controls.
Patients received radiation in doses of 40–70 Gy in 4–7 weeks. SCLs were again estimated in patients following irradiation.
The mean SCL was significantly higher (P<0.001) in cancer patients as compared to healthy controls. It declined significantly
(P<0.001) following irradiation. However, it remained significantly higher as compared to healthy controls (P<0.01). Highest
fall in SCL was seen in complete clinical responders and least in non-responders to radiation treatment. Serial estimation
of SCLs may be useful in the treatment monitoring of the neoplasms undergoing radiation treatment. 相似文献
10.
Suman B. Sharma Seema Garg Abhinav Veerwal Sridhar Dwivedi 《Indian journal of clinical biochemistry : IJCB》2008,23(4):334-336
Premature coronary artery disease (CAD) is common in India. We, therefore, studied oxidative stress, dyslipidemia, and high
sensitivity-C reactive protein (hs-CRP) levels in young CAD patients. Present study consisted of male CAD patients below 40
years and age and sex matched healthy controls (n=30 each). Fasting blood samples were analyzed for serum lipid profile, malondialdehyde,
antioxidant enzymes and hs-CRP levels. Dyslipidemia was observed in 90% of the young CAD patients, of which 72.2% showed increased
serum triglycerides and decreased HDL-cholesterol. LDL-cholesterol levels were high in 77.8%. Serum malondialdehyde and hs-CRP
levels were increased significantly (p<0.0001) as compared to controls. hs-CRP levels were in high risk range in all the young
patients. However, glutathione peroxidase activity was reduced significantly (p<0.05). Our data suggests that elevated hs-CRP
levels along with dyslipidemia and oxidative stress adds to the predictive value of premature CAD in young Indians. 相似文献