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111.
Effect of Adhesive Layer Thickness and Drug Loading on Estradiol Crystallization in a Transdermal Drug Delivery System 总被引:1,自引:0,他引:1
Mohammad Imani Farzad Lahooti-Fard Seyyed Mojtaba Taghizadeh Mitra Takrousta 《AAPS PharmSciTech》2010,11(3):1268-1275
The effects of adhesive layer thickness and drug loading on estradiol crystallization were studied in a drug-in-adhesive patch.
Patches containing different estradiol loadings (1.1% and 1.6% w/w) in different thicknesses (45, 60, and 90 μm) were prepared by coating of a homogenous mixture of adhesive solution and the
drug on a siliconized release liner by a film applicator. After drying, the film was laminated on a Poly(ethylene terephthalate)
backing layer and cut into appropriate size. Release tests were performed using thermostated Chien-type diffusion cells. Cross-section
of the patches was observed by optical microscopy. Scanning electron microscopy was done for surface analysis of the patches
after drug release test. Crystal formation was not expected in the adhesive layer based on the linear free-energy relationship
formalisms however; crystalline regions were observed in different locations through the thickness of the patches. These regions
were significantly more discontinuous in 45 μm samples which elucidated the effective role of adhesive layer thickness in
drug crystallization. Extensive crystallization observed for thicker patches was attributed to the strong crosslinking capability
of estradiol hemihydrate. Drug release study confirmed some of the crystallization results. No significant increase was observed
in the burst release with increasing in thickness from 45 to 60 μm which can be attributed to the severe increase in the crystallization
extent. Also, formation of a crystalline layer near the releasing surface and more discontinuous pattern of the crystals in
some samples was confirmed by investigation of the drug release curves. 相似文献
112.
Alam Farzad Neal S. Penneys Abdul Ghaffar Vincent A. Ziboh Jean Schlossberg 《Prostaglandins & other lipid mediators》1977,14(5):829-837
The biosynthesis of PGE2 and PGF2α was measured in intact peritoneal exudate preparations obtained fom -treated and control C3H mice. Although both the control and stimulated preparations biosynthesized PGF2α and PGE2 from [1–14C] arachidonic acid, the stimulated preparations generated more of both prostaglandins than did nonstimulated preparations, probably as a result of increased synthesis within macrophages. Increased transformation of PGE2 into PGF2α 9-ketoreductase was noted in stimulated preparations when compared to that in control cells. The data suggest that stimulated macrophages are capable of generating increased quantities of PGF2α and therefore might function as one source of this substance in resolving inflammatory reactions. 相似文献
113.
Maryam Tohidi Mitra Hasheminia Reza Mohebi Davood Khalili Farhad Hosseinpanah Babak Yazdani Amir Ahmad Nasiri Fereidoun Azizi Farzad Hadaegh 《PloS one》2012,7(9)
To examine, the predictors of incident chronic kidney disease (CKD) in a community-based cohort of Middle East population, during a mean follow-up of 9.9 years. In a sample of 3313 non-CKD Iranian adults ≥20 years the estimated glomerular filtration rate (eGFR) was calculated at baseline and at three year intervals during three consecutive phases. The eGFR <60 mL/min/1.73 m2 was defined as CKD. Multivariate Logistic regression analysis was used to determine the independent variables associated with incident CKD. The incidence density rates of CKD were 285.3 and 132.6 per 10,000 person-year, among women and men, respectively. Female gender per se was associated with higher risk of CKD, compared with males. Among women, age, eGFR, known diabetes, being single or divorced/widowed, hypertension (marginally significant) and current smoking were independent risk factors for CKD; however the intermediate degree of education and family history of diabetes decreased the risk by 40% (P<0.05). Among male subjects, independent predictors of developing CKD included aging and hypertension (with significantly higher risk than in women, P for interaction<0.05), eGFR, new diagnosed diabetes, high normal blood pressure; abdominal obesity decreased the risk of CKD about 30% which was marginally significant. In the Iranian population,>2% of individuals develops CKD each year. Our findings confirmed that sex- specific risk predictors should be considered in primary prevention for incident CKD. 相似文献
114.
Khalili D Mosavi-Jarrahi A Eskandari F Mousavi-Jarrahi Y Hadaegh F Mohagheghi M Azizi F 《PloS one》2012,7(2):e31427
Objective
The aim of this study was to evaluate the validity of cause of death stated in death certificates in Tehran using outcome measures of the Tehran Lipid and Glucose Study (TLGS), an ongoing prospective cohort study.Methods
The cohort was established in 1999 in a population of 15005 people, 3 years old and over, living in Tehran; 3551 individuals were added to this population three years later. As part of cohort''s outcome measures, deaths occurring in the cohort are investigated by a panel of medical specialists (Cohort Outcome Panel-COP) and underlying cause of death is determined for each death. The cause of death assigned in a deceased''s original death certificate was evaluated against the cause of death determined by COP and sensitivity and positive predictive values (PPV) were determined. In addition, determinants of assigning accurate underlying cause of death were determined using logistic regression model.Result
A total of 231 death certificates were evaluated. The original death certificates over reported deaths due to neoplasms and underreported death due to circulatory system and transport accidents. Neoplasms with sensitivity of 0.91 and PPV of 0.71 were the most valid category. The disease of circulatory system showed moderate degree of validity with sensitivity of 0.67 and PPV of 0.78. The result of logistic regression indicated if the death certificate is issued by a general practitioner, there is 2.3 (95% CI 1.1, 5.1) times chance of being misclassified compared with when it is issued by a specialist. If the deceased is more than 60 years, the chance of misclassification would be 2.5 times (95% CI of 1.1, 5.9) compared with when the deceased is less than 60 years. 相似文献115.
Ghaemian A Salehifar E Jalalian R Ghasemi F Azizi S Masoumi S Shiraj H Mohammadpour RA Bagheri GA 《Biological trace element research》2011,143(3):1239-1246
Oxidative stress is involved in the pathogenesis of congestive heart failure (CHF). Some trace elements serve as antioxidant
defenses. The purpose of this study was to analyze the effect of atrial fibrillation (AF) on zinc (Zn) and copper (Cu) levels
in patients with advanced CHF. In this prospective study, serum Zn and Cu levels in 78 patients with clinically advanced CHF,
i.e., New York Heart Association (NYHA) functional class III or IV (40 patients with AF and 38 in sinus rhythm) were measured
using atomic absorption spectrophotometry. All patients also had a left ventricular ejection fraction (EF) of <35%. We recruited
40 volunteers with nearly the same age and weight as control. They had normal EF. There was no significant difference between
patients with AF and those with sinus rhythm regarding serum Zn and Cu levels. However, both groups showed significant hypozincemia
(p < 0.000) and a decreased Zn/Cu ratio (p < 0.03) compared with control group. Serum Cu levels were similar in the two groups and did not differ significantly from
the control group. In patients with advanced CHF, irrespective of the rhythm, profound hypozincemia, and a decreased Zn/Cu
ratio were present, which could be secondary to the activation of the renin–angiotensin–aldosterone system and CHF medications.
The results suggest the need for more studies focusing on possible benefits with Zn nutriceutical replacement in patients
with advanced CHF. 相似文献
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117.
Effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on DNA damage in biological systems are still a matter of dispute. The aim of the present study was to investigate the possible effect of electromagnetic field exposure on DNA fragmentation in cells (blastomers) of mouse blastocysts. Eighty female NMRI mice were randomly divided into 2 groups of 40 animals each. The control group was left unexposed whereas the animals in the EMF-group were exposed to a 50-Hz EMF at 0.5?mT 4?h per day, 6 days a week for a duration of 2 weeks. After the 8(th) day of exposure, the female mice in both groups were superovulated (with injections of pregnant mare serum gonadotropin and human chorionic gonadotropin) and then mated overnight. At approximately 4 days after mating (102?h after the human chorionic gonadotropin treatment), blastocysts were obtained by flushing the uterus horns. The mean numbers of pregnant mice, blastocysts after flushing, blastomers within the blastocysts, and the DNA fragmentation index following staining in both groups were compared using statistical methods (SPSS, the Chi-square test, the Student's t-test and the Mann-Whitney U-test, P?0.05). The results showed that the mean number of blastocysts after flushing was significantly decreased in the EMF-group compared to that of the control group (P?0.03). The DNA fragmentation index was significantly increased in the EMF-group compared to control (10.53% vs. 7.14%; P?0.001). However, there was no significant difference in the mean numbers of blastomers and numbers of pregnant mice between the EMF-exposed and control group. Our findings indicate that the EMF exposure in preimplantation stage could have detrimental effects on female mouse fertility and embryo development by decreasing the number of blastocysts and increasing the blastocysts DNA fragmentation. 相似文献
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119.
Shah SR Esni F Jakub A Paredes J Lath N Malek M Potoka DA Prasadan K Mastroberardino PG Shiota C Guo P Miller KA Hackam DJ Burns RC Tulachan SS Gittes GK 《Developmental biology》2011,349(2):371-349
The mammalian embryo represents a fundamental paradox in biology. Its location within the uterus, especially early during development when embryonic cardiovascular development and placental blood flow are not well-established, leads to an obligate hypoxic environment. Despite this hypoxia, the embryonic cells are able to undergo remarkable growth, morphogenesis, and differentiation. Recent evidence suggests that embryonic organ differentiation, including pancreatic β-cells, is tightly regulated by oxygen levels. Since a major determinant of oxygen tension in mammalian embryos after implantation is embryonic blood flow, here we used a novel survivable in utero intracardiac injection technique to deliver a vascular tracer to living mouse embryos. Once injected, the embryonic heart could be visualized to continue contracting normally, thereby distributing the tracer specifically only to those regions where embryonic blood was flowing. We found that the embryonic pancreas early in development shows a remarkable paucity of blood flow and that the presence of blood flow correlates with the differentiation state of the developing pancreatic epithelial cells in the region of the blood flow. 相似文献
120.
Arash Derakhshan Mahsa Sardarinia Davood Khalili Amir Abbas Momenan Fereidoun Azizi Farzad Hadaegh 《PloS one》2014,9(7)