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131.
Kusal K. Das Amrita Das Gupta Salim A. Dhundasi Ashok M. Patil Swastika N. Das Jeevan G. Ambekar 《Biometals》2007,20(2):177-184
In this experimental study, we investigated whether l-ascorbic acid has any influence on the blood antioxidant defense system, lipid peroxidation and hematological parameters
of the albino rats exposed to nickel sulfate(NiSO4).Twenty four adult rats were divided into four groups of six animals in each group. The control rats were untreated and comprised
Group I. Group II rats were administered nickel sulfate (2.0 mg/100 g b.wt.; intraperitonially, i.p.). Group II rats were
treated orally l-ascorbic acid (50 mg/100 g b.wt.) and Group IV rats were given both nickel sulfate and l-ascorbic acid simultaneously on alternate days until the tenth dose. The hematological parameters were assessed: red blood
corpuscle counts, packed cell volume %, hemoglobin concentration, white blood corpuscle counts and platelets count decreased
significantly and clotting time increased significantly in nickel treated rats. We also observed increase malondialdehyde
(MDA) and decrease glutathione level (GSH) in erythrocytes of nickel treated rats. The activities of erythrocyte antioxidant
enzymes like superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were significantly increased in
rats treated with nickel sulfate. Simultaneously treatment of l-ascorbic acid exhibited a possible protective role on the toxic effect of nickel sulfate on the hematological values, erythrocyte
MDA and GSH concentrations as well as antioxidant enzymatic defense system. 相似文献
132.
133.
Abhrak bhasma is a commonly used ayurvedic drug against many diseases including hepatitis. It is tested in albino rats using a model of hepatitis induced by a single dose of CCl4 (3 ml/kg body wt). Different doses of abhrak bhasma (10, 20, 30 and 40 mg/kg body wt) were tested to decide the dose related hepatoprotective efficacy. The centrolobular necrosis induced by single dose of CCl4 was reduced significantly by abhrak bhasma (10 mg) and liver histology was also protected by 20 mg dose. Liver acid lipase activity was lowered, while alkaline and lipoprotein lipase activities were elevated due to treatment of single dose of CCl4. Abhrak bhasma counteracted the action of CCl4 on liver lipolytic enzymes. CCl4 did not alter the kidney histologically. Activities of three lipases of rat kidney (acid, alkaline and lipoprotein lipases) were reduced by CCl4 treatment and were reversed by administration of abhrak bhasma. Acid lipase activity of rat adipose tissue was reduced by CCl4 treatment. On the contrary alkaline, lipoprotein and hormone sensitive lipases were enhanced after 24 hr of administration of CCl4. Acid lipase activity was raised by administration of different doses of abhrak bhasma concurrent with CCl4. Abhrak bhasma treatment along with CCl4 enhanced alkaline lipase activity at 10 and 20 mg dose and later it was reduced at 30 and 40 mg doses and came to normal levels. Lipoprotein and hormone sensitive lipases were reduced by the counteraction of increasing doses of abhrak bhasma. 相似文献
134.
Patil B.B. Wakharkar R.D. Chincholkar S.B. 《World journal of microbiology & biotechnology》1999,15(2):265-268
The fungus Cunninghamella blakesleeana NCIM 687, industrially recognized for progesterone biotransformation, was found to produce two siderophores at low stress of iron (upto 40 M iron in the growth medium). HPLC analysis and direct comparison with authentic samples characterized one of them as ferrichrysin (hydroxamate type) and other probably as a member of the coprogen family of siderophores. 相似文献
135.
Nicotine (2 and 4 mg/kg body weight, i.p.) administered to albino rats for 20 days decreased the number of healthy follicles and increased the number of regressing follicles in the ovary. Uterine weight, its diameter, thickness of myometrium and endometrium and height of epithelium were reduced. Increase in the ovarian cholesterol level and decrease in glycogen content in nicotine treated rats indicate the inhibition brought in the steroidogenesis which is dependent on pituitary gonadotrophins. Decreased protein content of the ovary and uterus may be due to their retarded growth. Reduced number of estrous cycle with prolonged metaestrus and diestrus also supports the decreased estrogen synthesis responsible for cornification of vaginal smear in nicotine treated rats. 相似文献
136.
Preparation of chiral gamma-substituted-gamma-lactones (1) through kinetic resolution is described. (S)-(-)-1-Phenylethylamine (2) in the presence of anhydrous AlCl(3) shows satisfactory levels of enantioselection in reaction with racemic gamma-substituted-gamma-lactones 1, where (R)-1 remains unreacted, while (S)-1 is enantioselectively converted to the ring-opened amide (S,S)-4. The enantiopurity of (R)-(+)- gamma-substituted gamma-lactones recovered ranges from 62-98% ee. 相似文献
137.
138.
The purpose of this study was to formulate a gelled self-emulsifying drug delivery system (SEDDS) containing ketoprofen as
an intermediate in the development of sustained release solid dosage form. Captex 200 (an oil), Tween 80 (a surfactant), and
Capmul MCM (a cosurfactant) were used to formulate SEDDS. Silicon dioxide was used as a gelling agent, which may aid in solidification
and retardation of drug release. Effect of concentrations of cosurfactant and gelling agent on emulsification process and
in vitro drug diffusion was studied using 32 factorial design. Multiple regression analysis data and response surfaces obtained showed that liquid crystal phase viscosity
increased significantly with increasing amount of silicon dioxide, which in turn caused an increase in average droplet size
of resultant emulsion and slower drug diffusion. Drug release from the formulation increased with increasing amount of cosurfactant. 相似文献
139.
Conclusion Hydrolyzed gelatins (Byco-A, Byco-O and Byco-C), when used as binders, yielded soft, uniform granules with good flow properties.
As the molecular weight and viscosity of hydrolyzed gelatins increased, the compressibility of granules decreased and their
compactability increased. The balance between compressibility and compactability of granules may be achieved by careful monitoring
of the molecular weight of hydrolyzed gelatins that can serve as potential binders. 相似文献
140.
Diversity of the native diazotrophs associated with the rhizosphere of pearl millet (P. glaucumn), grown in nutritionally poor soils of semi-arid regions was studied with a view to isolate effective nitrogen fixing and plant growth stimulating bacteria with root associative characteristics. The native population varied from 10(3)-10(4) g(-1) of rhizosphere soil after 40 d growth and belonged to genera Azospirillum, Azotobacter and Klebsiella. Another non-diazotrophic root associative group was Pseudomonas sp., which also produced IAA and enhanced plant growth. Some of these rhizobacteria showed high in vitro acetylene reduction activity along with production of indole acetic acid. Out of 11 selected diazotrophs used as seed inoculants, M10B (Azospirillum sp.), M11E (Azotobacter sp.) and M12D4 (Klebsiella sp.) resulted in significant increase in total root and shoot nitrogen at 45 and 60 days of plant growth under pot culture conditions. 相似文献