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101.
BACKGROUND: Control of hyperlipidemia is vital in patients with cardiovascular disease (CVD). Omega-3 fatty acids (n-3FAs) have desirable effects on serum triglyceride (TG) levels, thrombosis, and arrhythmia, but lead to increases in serum low-density lipoprotein (LDL) and apo-B as well. OBJECTIVE: To determine and compare the effects of administration of n-3FAs, vitamin C (VitC) and n-3FAs + VitC on the serum levels of LDL, apoB, other serum lipids, and malondialdehyde (MDA). The present study was performed in Tehran University of Medical Sciences from 2000 to 2001. DESIGN: In a double-blind, placebo trial of parallel design, 68 hyperlipidemic patients [total cholesterol (TC) and TG greater than 200 mg/dL] were randomly assigned to receive daily 500 mg VitC, 1 g n-3FAs, 500 mg VitC + 1 g n-3FAs, or placebo (control) for 10 weeks. Fasting blood samples were collected at the beginning and at the end of the period. TG, TC, LDL-cholesterol-C (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) were measured enzymatically, VitC and MDA colorimetrically, and apo-B and apo-A-I immunoturbidometrically. The pattern of food consumption, socio-economic, and anthropometric indices were determined; there was no significant change in these indices during the study. RESULTS: There was a significant difference in the blood VitC level at the end of the study in comparison to the initial value in the VitC (p = 0.001) and VitC + n-3FAs (p = 0.027) groups. Similarly, the serum TG level at the end of study was significantly different from the initial value in the n-3FAs group (p = 0.002) and also from the final value in the control group (p = 0.013). In the VitC group, there was a significant decrease in TC (p = 0.004), apo-B (p = 0.005), and MDA (p = 0.015) at the end of study as compared to the respective initial values. There was also a significant increase in blood VitC compared to the control value (p = 0.018) and a significant decrease in MDA compared to the n-3FAs group (p = 0.034). At the end of study, in the n-3FAs group, there was a significant (p = 0.04) and a marginally significant decrease (p = 0.05), respectively, in TG/HDL and apo-B levels as compared to the initial values, and the TG/HDL ratio showed a significant decrease as compared to the control group (p = 0.047). CONCLUSION: Simultaneous administration of n-3FAs and VitC had no beneficial effects on the lipid profile of hyperlipidemic patients, but 1 g purified n-3FAs daily for 10 weeks is a beneficial supplement for decreasing TG without any increase in LDL-C, apo-B or MDA. Administration of 500 mg VitC for more than 10 weeks might decrease significantly TC and apo-B in hyperlipidemic patients.  相似文献   
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The idiotype network is important both as a means of autoregulation of immune mechanisms and a potential tool for manipulation of abnormal responses. In the autoimmune disease myasthenia gravis the acetylcholine receptor (AChR) is the target of an aberrant immune response. In this study we compare 2 widely used methods of antibody determination--immunoprecipitation radioimmunoassay (IPRA) and enzyme-linked immunoassay (ELISA)--for their ability to detect both anti-AChR antibodies (polyclonal and monoclonal) and anti-idiotypic antibodies raised against polyclonal anti-AChR antibodies. Although the IPRA is considerably more sensitive for the detection of monoclonal anti-AChR antibodies, the 2 methods produce similar results in the detection of anti-idiotypic antibodies to the anti-AChR immune response. The 2 techniques also demonstrated specificity of the reagents for idiotypes associated with the anti-AChR response and absence of effect on an idiotype associated with the control antigen, ovalbumin. The results demonstrate that the idiotypic repertoire of the polyclonal anti-AChR response in C57B1/6 mice is sufficiently restricted that antigen-specific blocking anti-idiotypic antibodies can be raised in rabbits by immunization with anti-AChR antibodies.  相似文献   
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Benzene is classified as carcinogenic compound which is emitted mainly from cars. In this study, benzene was measured at various sites in Nibong Tebal (urban, suburban, town, and rural) of different traffic volume, and traffic counts were performed simultaneously. Monitoring was carried out during the morning and afternoon traffic peaks. The aim of this study is to monitor benzene concentration at several development sites with different traffic flow. The monitoring was done by using indoor air quality meter. The results obtained from monitoring show that the mean concentrations of benzene ranged from 54.7 ppb in the suburban area to 115.1 ppb in the town area. Multiple linear regression analysis correlated the benzene concentrations with traffic volume, temperature, humidity, and time of monitoring as predictors. The results show that R 2 of the model was 0.97 in Taman Cowin site, and it was 0.47 in Taman Nibong Tebal Jaya site. Negative correlation was found between benzene concentration and temperature while there was positive correlation with humidity being found through the study. Pearson’s correlation indicates that gasoline vehicular exhaust could be the major source of benzene. The UK Air Quality Standards stipulated that the annual mean of ambient benzene should not exceed 5 ppb or 16.25 μg/m3. The results show that the current concentrations of benzene exceeded the permissible limits set by the UK standards.  相似文献   
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Abstract:  Elastic fibres are essential extracellular matrix components of the skin, contributing to its resilience and elasticity. In the course of skin ageing, elastin synthesis is reduced, and elastase activity is accelerated, resulting in skin sagging and reduced skin elasticity. Our studies show that non-denatured Glycine max (soybean) extracts induced elastin promoter activity, inhibited elastase activity and protected elastic fibres from degradation by exogenous elastases in vitro . Mouse and swine skins topically treated with soybean extracts showed enhanced elastic fibre network and increased desmosine content. Elastin expression was also augmented in human skin transplanted onto SCID mice in response to soy treatment. These data suggest that non-denatured soybean extracts may be used as skin care agents to reduce the signs of skin ageing.  相似文献   
109.
This report describes a phase I clinical trial using nonmyeloablative, lympho-depleting chemotherapy in combination with adoptive immunotherapy in patients with metastatic melanoma. The chemotherapy-conditioning schedule that induced transient lymphopenia consisted of cyclophosphamide (30 or 60 mg/kg per day for 2 days) followed by fludarabine (25 mg/m(2) per day for 5 days). Immunotherapy for all patients consisted of in vitro expanded, tumor-reactive, autologous T-cell clones selected for high avidity recognition of melanoma antigens. Cohorts of three to six patients each received either no interleukin (IL)-2, low-dose IL-2 (72,000 IU/kg intravenously three times a day to a maximum of 15 doses), or high-dose IL-2 (720,000 IU/kg intravenously three times a day for a maximum of 12 doses). The toxicities associated with this treatment were transient and included neutropenia and thrombocytopenia that resolved in all patients. High dose intravenous IL-2 was better tolerated by patients after chemotherapy than during previous immunotherapy cycles without chemotherapy. No patient exhibited an objective clinical response to treatment, although five patients demonstrated mixed responses or transient shrinkage of metastatic deposits. This study established a nonmyeloablative-conditioning regimen that could be safely administered in conjunction with adoptive T-cell transfer and IL-2 in patients with metastatic melanoma.  相似文献   
110.
ABSTRACT: The refusal to donate an organ is a phenomenon in need of exploration and explanation. This article refers to the major fear of becoming an organ donor in relation to a global culture perspective and to the Halacha (Jewish law). A theoretical critique about the ambivalence demonstrated by health care providers and families will discuss these concepts in relation to brain death, from the stages of hospitalization, through the period prior to the assertion of brain death, ending with brain death, and its perspective as a liminal situation.Finally, we conclude that nursing practices during the care of the "brain dead" patient, and toward the patient's family, should convey an unequivocal message. That is, brain death describes irreversible cessation of all brain function, and therefore, the patient becomes a dead body and can be treated as a potential organ donor.  相似文献   
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