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61.
The aim of the present study was to assess the association between smoking and the alteration in plasma concentration of lipid profile and lipid peroxides. Fourteen smokers and 11 age matched control were enrolled. Plasma levels of fasting cholesterol, triglycerides, lipoprotein cholesterol and malondialdehyde were estimated. In smokers the levels of total cholesterol, LDL cholesterol, Non-HDL cholesterol and MDA were significantly elevated when compared with the controls. The atherogenic index as indicated by various risk ratios were also found to be increased in smokers as compared to controls. These findings indicate that current smokers are at a pro- atherogenic state and as in other countries, in India smokers require particular attention in terms of public health interventions.  相似文献   
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PURPOSE: To describe the methodology and baseline data for the Antioxidants in Prevention of Cataracts (APC) study in South India. METHODS: The APC study is a prospective, 5-year, randomized, triple-masked, placebo-controlled, field-based clinical trial to examine the effect of antioxidants (combination tablet of vitamins A, C, and E) on progression of cataract. The primary outcome variable is cataract progression (nuclear opalescence), evaluated with the slit-lamp biomicroscope by the Lens Opacification Classification System III method. Secondary outcome variables are progression in cortical and posterior subcapsular opacity and nuclear color, change in best corrected visual acuity, myopic shift, and treatment failure (progression to cataract surgery or best corrected vision worse than 20/400 in an eye). Inclusion criteria are age between 35 and 50 years and best-corrected visual acuity of 20/40 or better. Exclusion criteria are a diagnosis of diabetes mellitus or nonfasting blood glucose level>7.8 mmol/L, history or presence of various ocular conditions or treatment forms, or current use of vitamin supplements. Baseline ophthalmic, demographic, and potential cataract risk factor data (such as smoking, sunlight, or alcohol exposure) were compared between groups on an intent-to-treat basis. RESULTS: Of 954 people screened, 798 were enrolled, a sample size which exceeded the required estimate. More than 80% of subjects had 20/20 or better vision in at least one eye, and baseline prevalence of significant cataract according to the LOCS III grading scale was high. The two treatment groups were comparable for all baseline measures except alcohol intake. CONCLUSION: The sample size and group baseline characteristics will provide sufficient power to detect a change in cataract progression within 5 years.  相似文献   
64.
PURPOSE: A controlled-release drug delivery of contraceptive steroids levonorgestrel (LNG) and ethinyl estradiol (EE) has been developed by successful encapsulation of LNG and EE in poly (lactide-co-glycolide) (PLG) microspheres. MATERIALS AND METHODS: Smooth, spherical, steroid-loaded PLG microspheres with a mean size of 10-25 microm were prepared by using the water/oil/water double-emulsion solvent evaporation method. RESULTS: In vitro release profiles showed an increased burst release of LNG/EE on Week 1; thereafter, the release was sustained. At the end of Week 7, the release of LNG/EE from 1:5 and 1:10 PLG microspheres was 75.64% and 62.55%. respectively. In vitro degradation studies showed that the PLG microspheres maintained surface integrity up to Week 8 and then eroded completely by Week 20. In an in vivo study, the serum concentration of LNG/EE in rats showed a triphasic release response, with an initial burst release of 8 ng/mL LNG and 14 pg/mL EE on Day 1; thereafter, a controlled release of the drugs to the systemic circulation was maintained until Week 15, maintaining constant drug levels of 2 ng/mL LNG and 3-4 pg/mL EE in the blood. Histological examination of steroid-loaded PLG microspheres injected intramuscularly into the thigh muscle of Wistar rats showed minimal inflammatory reaction, demonstrating that contraceptive-steroid-loaded microspheres were biocompatible. CONCLUSION: This controlled-release and biocompatible nature of the PLG microspheres may have potential application in contraceptive therapy.  相似文献   
65.
The loss of genetic diversity poses a serious threat to the conservation of endangered species, including wild felids. We are attempting to develop spermatogonial stem cell transplantation in the cat as a tool to preserve and propagate male germ-plasm from genetically valuable animals, be they threatened wild species or lines of cats used as models for inherited diseases. In this study, we investigated the use of local external beam radiation treatment to deplete the endogenous germ cells of male domestic cats, a step necessary to prepare them for use as recipients for transplantation. Testes of 5-month-old domestic cats were irradiated with a fractionated dose of 3 Gy per fraction for 3 consecutive days. These cats were castrated at 2, 4, 8, 16, and 32 weeks posttreatment, and progress of spermatogenesis was evaluated histologically and compared against age-matched controls. Even at the latest time points, less than 10% of tubules contained germ cells at any stage of meiosis, showing the efficacy of this protocol. In addition, male germ cells were isolated from the testes of domestic cats using a 2-step enzymatic dissociation to establish a protocol for the preparation of donor cells. The presence and viability of spermatogonia within this population were demonstrated by successful transplantation into, and colonization of, mouse seminiferous tubules. The success of these protocols provides a foundation to perform spermatogonial stem cell transplantation in the domestic cat.  相似文献   
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68.
Spherical gold nanoparticles of approximately 16 nm were synthesized using a sonochemical reduction method and characterized using UV–vis spectroscopy, atomic force microscopy (AFM) and transmission electron microscopy (TEM). The binding of these gold nanoparticles with bovine serum albumin (BSA) and human serum albumin (HSA) was investigated using UV–vis absorption and fluorescence spectroscopic techniques. A strong quenching of the fluorescence from serum albumins was observed due to the formation of a ground state complex with gold nanoparticles (static quenching). The fluorescence quenching constants, number of binding sites and binding constants were determined using Stern–Volmer and Benesi–Hildebrand plots. Using Forster Resonance Energy Transfer (FRET) theory, the distance between the donor (serum albumins) and acceptor (gold nanoparticles) was obtained, which showed that HSA has more affinity towards sonochemically synthesized gold nanoparticles compared to gold nanoparticles synthesized using other methods.  相似文献   
69.

Objective

To evaluate the antioxidant activity of alcoholic leaf-extract of Solanum surattense (Solanaceae) (S. surattense).

Methods

Leaf extract were tested for in vitro free radical scavenging assays, such as hydroxyl radical and hydrogen peroxide, inhibition of superoxide anion radical and 2, 2-diphenyl-1-picryl hydrazyl radical (DPPH), total antioxidant activity and reducing ability. Further, total phenolic content of S. surattense was analyzed.

Results

S. surattense extract effectively scavenged free radicals at all different concentrations and showed its potent antioxidant activity. Further, these effects were in a dose dependent manner. Results were compared to standard antioxidants such as butylated hydroxytoluene, ascorbic acid and α-tocopherol.

Conclusions

S. surattense have strong antioxidant potential. Further the study validates the therapeutic benefits of the Indian system of medicine.  相似文献   
70.
A three-dimensional quantitative structure–activity relationship of 66 structurally and functionally diverse series of 1-substituted imidazoles with antifungal activity was studied using the CoMSIA method. The compounds were divided into a training set of 56 molecules and a test set of 10 molecules. The optimum CoMSIA model obtained for the training set were all statistically significant with cross-validated coefficients (q 2) of 0.725 and conventional coefficients (r ncv 2 ) of 0.998. The predictive ability of CoMSIA was determined using a test set of ten imidazole derivatives. CoMSIA model (Model 1) obtained from steric, electrostatic, and H-bond acceptor fields were found to have best predictivity with a predictive correlation coefficient (r pred 2 ) of 0.60. Based upon the information derived from CoMSIA, it is evident that steric, electrostatic, and hydrogen bond acceptor groups may be important for the design of more potent imidazole analogs as potent Candida P450DM inhibitors.  相似文献   
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