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121.
P-selectin, a cell adhesion molecule is elevated in many inflammatory conditions including preeclampsia which is characterized by generalized endothelial dysfunction and vasoconstriction presumably due to free radicals or mediators released by defective placentation. Vitamin E has been documented to protect cell membranes from oxidative damage and also decrease platelet aggregation. The role of vitamin E in pre-eclampsia is contradictory and hence the study was undertaken. Soluble P-selectin was measured by ELISA and Vitamin-E levels in plasma was estimated spectrofluorometrically. In our study the effect of supplementation of 400 IU/day of Vitamin E (a-tocopheryl acetate) to patients of pre-eclampsia showed significant decreased levels of soluble P-selectin by 2nd week as compared to patients given placebo (P = 0.005). In this short period of study no direct correlations were observed between Vitamin E or P-selectin levels with blood pressure as well as with proteinuria. Future studies may focus on the effect of a-tocopheryl acetate or the phosphate form of Vitamin-E, recently proposed to be the more active form on other inflammatory markers like IL-6, an important stimuli of P-selectin release in pre-eclampsia.  相似文献   
122.
Familial hypercholesterolemia (FH) is an autosomal dominant disorder of lipoprotein metabolism caused mainly by mutations in the low-density lipoprotein receptor (LDLR) and apolipoprotein B 100 (APOB) genes. Until now, the molecular basis of FH has been demonstrated in detail in many populations, but there is still very limited Molecular data concerning FH in Iran. The aim of this study was to characterize the LDLR and APOB gene mutations in an Iranian population. A total of 30 non-related Iranian possible FH subjects were studied. Diagnosis of FH was based on the Dutch Lipid Clinic Network diagnostic criteria. All samples were initially tested for three common APOB gene mutations including R3500Q, R3500 W and R3531C using PCR-RFLP assay. Subsequently, promoter and coding region of the LDLR gene was screened by PCR-SSCP analysis and positive results were confirmed by DNA sequencing. Four previously reported polymorphisms 1413G > A, 1725C > T, 1773T > C and 2140 + 5G > A were found in ~17% (5/30) of population studied. Moreover, no variation was found in APOB gene. Our data indicated that LDLR and APOB gene mutations have not contribution to possible FH in Iranian population studied here. However, we examined three common APOB mutations and LDLR in only 30 patients, and to determine the role of these genes in developing FH in Iran, more FH samples and populations needed to be investigated for the mutations of the related genes.  相似文献   
123.
The present study evaluated the plausible role of circulating biomarkers in immune pathogenesis of chronic hepatitis considered a priority in clinical hepatology. Total viral load of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) patients was quantified and correlation studies were performed with circulating levels of Th1/Th2 cytokines; C reactive protein and circulating nucleosomes; glutathione reductase (GR) and superoxide dismutase. To our knowledge, the study is first among its kind that validates strong positive correlation of viral load with IL-4, IL-6, GR in HBV and IL-6, IL-10, GR in HCV infections. Although, multi-centric studies including large cohorts are required for translating our findings to clinical practice, however, role of these biomarkers with potential diagnostic or prognostic significance might be helpful in clinical assessment of high-risk individuals, thereby, designing interventional strategies, towards development of personalized medicare. The results of our study also offer valuable insights of immune signaling mediators engaged in development of hepatocellular carcinoma.  相似文献   
124.
Now a days measurement of molecular forms of PSA has gained importance in clinical practice. Several studies have demonstrated the production of PSA in female tissues, such as breast. The present piece of work has been undertaken with an objective to estimate the relative proportion of the molecular forms of PSA in serum along with serum testosterone in benign and malignant breast tumor cases and to analyze their association with the severity of the disease process 34 malignant and 26 benign breast disease cases along with 33 healthy controls of same age group were enrolled in this study for evaluation. Serum testosterone was measured by ELISA, whereas serum total PSA (TPSA) and free PSA (FPSA) were estimated by electrochemiluminescence immunoassay. A significant rise of fasting plasma glucose along with prominent dyslipidemia was observed in breast tumor cases. Marked rise in serum testosterone as well as TPSA and FPSA was documented in both benign and malignant breast tumor cases. Serum testosterone revealed a significant positive association with both TPSA and FPSA pointing towards an etiological association between them. However, surgical removal of tumor mass resulted in a marked decline of presurgical value of both TPSA and FPSA with a non-significant fall in serum testosterone revealing tumor tissue as the source of FPSA and TPSA. Thus, estimation of PSA provides prognostic information that may assist in future treatment.  相似文献   
125.
Nitric oxide (NO) a free radical having both cytoprotective as well as tumor promoting agent is formed from l-arginine by converting it to l-citrulline via nitric oxide synthase enzymes. The reaction product of nitric oxide with superoxide generates potent oxidizing agent, peroxynitrite which is the main mediator of tissue and cellular injury. Peroxynitrite is reactive towards many biomolecules which includes amino acids, nucleic acid bases; metal containing compounds, etc. NO metabolites may play a key role in mediating many of the genotoxic/carcinogenic effects as DNA damage, protein or lipid modification, etc. The basic reactions of nitric oxide can be divided as direct effect of the radical where it alone plays a role in either damaging or protecting the cell milieu and an indirect effect in which the byproducts of nitric oxide formed by convergence of two independent radical generating pathways play the role in biological reactions which mainly involve oxidative and nitrosative stress. Nitric oxide is also capable of directly interacting with mitochondria through inhibition of respiration or by permeability transition. Reaction of nitric oxide with metal ions include its direct interaction with the metals or with oxo complexes thereby reducing them to lower valent state. Excessive production of nitric oxide can be studied by inhibiting the synthetic pathway of nitric oxide using both selective or specific nitric oxide synthase inhibitor or non-selective nitric oxide synthase inhibitor with respect to isoforms of nitric oxide.  相似文献   
126.
HIV/AIDS conspiracy theories constitute a loosely grouped set of meanings that share the notion of secret collusion among allied parties. This paper traces one woman's etiological narrative of HIV/AIDS. Such embodied experience and cultural understanding when placed against the backdrop of current thinking on the topic in the United States builds a new framework for understanding the emergence and circulation of HIV/AIDS conspiracy theories as "counter-narratives" employed by individuals and publics in the face of the AIDS pandemic. Such counter-narrative creates a rhetorical space for challenges to power through the articulation of oppositional ideas about dominant scientific knowledge. Without a critical exploration of HIV/AIDS conspiracy theories that examines their emergence and effects as a form of discourse circulating in the public domain, public health advocates will not be able to trace and respond to these narratives' impact on HIV prevention efforts or consider their relevance for other emerging infectious diseases.  相似文献   
127.
In spite of great expectations about the potential of nanotechnology, this study shows that people are rather ambiguous and pessimistic about nanotechnology applications in the food domain. Our findings are drawn from a survey of public perceptions about nanotechnology food and nanotechnology food packaging (N = 752). Multinomial logistic regression analyses further reveal that knowledge about food risks and nanotechnology significantly influences people's views about nanotechnology food packaging. However, knowledge variables were unrelated to support for nanofood, suggesting that an increase in people's knowledge might not be sufficient to bridge the gap between the excitement some business leaders in the food sector have and the restraint of the public. Additionally, opposition to nanofood was not related to the use of heuristics but to trust in governmental agencies. Furthermore, the results indicate that public perceptions of nanoscience in the food domain significantly relate to views on science, technology, and nature.  相似文献   
128.
Thyroid function tests are very important for the diagnosis and monitoring of patients with thyroid dysfunction. The guidelines recommend serum thyroid stimulating hormone (TSH) as the single most reliable test to diagnose all common forms of hypothyroidism and hyperthyroidism. The aim of this study was to analyze the ordering pattern for thyroid function tests by physicians and the analysis of results based on the clinical history. The mean age of the patients was 32.5 ± 6.5 years. Majority of samples (87.7% of total) were received from the departments of Medicine and Gynae. Thyroid profiles (47.5%) were ordered more frequently as compared to TSH only (46%). There was no significant difference in the percentage of normal reports for both types of tests. 77.8% of TFT and 76.6% of TSH samples had results within the reference range. The percentage of abnormal results was 13.7% in the patients who were screened for thyroid disorders. There is a need to redefine the case definition for thyroid dysfunction and order the appropriate test in a rational and cost effective manner.  相似文献   
129.
130.
Background: Thailand is a poor but highly literate country in South‐East Asia with over 60 million people. A lot of biomedical research is undertaken but dissemination is limited. Objectives: To identify relevant Thai bibliographic databases and investigate accessibility, functionality and content, particularly in relation to randomised controlled trials (RCTs) and clinical controlled trials (CCTs). Methods: A systematic search for institutions productive of research and the databases in their libraries. Search each accessible database in both Thai and English, recording the functionality and content. Assess accessibility of the retrieved RCTs or CCTs by comparing to Pub Med holdings. Results: We found 32 different databases (29 accessible in UK) of various sizes, coverage and functionality but many with unique records of RCTs and CCTs (total, n = 781). Two hundred and nine of 781 trials were accessible on Pub Med (27%). However, 641 of the 781 trial records contain text in both English and Thai (82%) and 112 records were solely English (14%). Conclusions: Those undertaking comprehensive searches for RCTs/CCTs should, in addition to a Pub Med , search the Thai Medical Index and Thai Index Medicus databases, and the Khon Kaen University Library Catalogue.  相似文献   
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