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991.
992.
今天我与大家交流美国国家档案馆(NARA)在保存历史和开放档案中面临的挑战以及我们正在通过怎样的方式将美国公众与他们的档案建立起联系。一、政务公开对档案工作的影响奥巴马总统在就职第一天就发表了关于政务公开倡议的演讲,他在最近发表的 相似文献
994.
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
995.
Farrokhi E Shayesteh F Asadi Mobarakeh S Roghani Dehkordi F Ghatreh Samani K Hashemzadeh Chaleshtori M 《Indian journal of clinical biochemistry : IJCB》2011,26(3):244-248
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
996.
Khan S Bhargava A Pathak N Maudar KK Varshney S Mishra PK 《Indian journal of clinical biochemistry : IJCB》2011,26(2):161-168
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
997.
Dash P Pati S Mangaraj M Sahu PK Mohapatra PC 《Indian journal of clinical biochemistry : IJCB》2011,26(2):182-186
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
998.
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
999.
Mackenzie S 《Public understanding of science (Bristol, England)》2011,20(4):491-505
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
1000.
Vandermoere F Blanchemanche S Bieberstein A Marette S Roosen J 《Public understanding of science (Bristol, England)》2011,20(2):195-206
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