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Hypertension, hypercholesterolemia, and coronary artery disease are among the risk factors of cerebrovascular accidents. After age, hypertension is the most powerful stroke risk factor. Abnormalities of serum lipids are regarded as risk factors for cerebrovascular accidents. A significant reduction in stroke risk among persons treated with cholesterol-reducing medicines known as statins are reported. Stroke risk nearly doubles in those with antecedent coronary artery disease. Moreover, polycythemia and high hematocrit levels are considered to be potential stroke risk factors. Minor thalassemia is associated with decreased prevalence of arterial hypertension and myocardial infarction (the second effect observed only in males.) Total cholesterol and LDL levels are lower in minor thalassemics, as is the blood viscosity. Therefore, it could be hypothesized that minor thalassemia could afford some protection against cerebrovascular accidents.  相似文献   
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Breast cancer is the prevalent cancer worldwide. Excessive exposure to endogenous estrogen across a woman's lifespan contributes to and may be a causal factor in breast cancer. Tamoxifen is a mixed estrogen agonist and antagonist, which is used in treatment and prevention of breast cancer as an estrogen antagonist. Many patients experience resistance to tamoxifen for which many mechanisms have been suggested. Endothelin-1 acts as a mitogen for human breast fibroblasts and it affects tumor cell proliferation, invasion, angiogenesis, neovascularization, mitogenesis, and apoptosis inhibition. Previous studies have shown that estradiol is effective in inhibiting endothelin synthesis in breast tissue and cardiovascular system. Tamoxifen as an estrogen receptor (ER) agonist in cardiovascular system has a cardioprotective effect and decreases endothelin level as a vasoconstrictor in cardiovascular system. But in breast tissue tamoxifen acts as an ER antagonist. According to the role of endothelin in breast cancer and inhibitory effect of estrogen on endothelin, we hypothesized that tamoxifen causes increasing in endothelin level or endothelin receptors probably by inhibitory effect on ER in breast tissue, leading to tamoxifen resistance. Therefore a combination of tamoxifen with endothelin antagonist seems to be a reasonable therapeutic strategy.  相似文献   
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Background: Cancer persists as one of the world’s most pressing maladies. Notable points about chemotherapy are drug side effects which are almost universally encountered. Emerging knowledge focusing on mechanisms of toxicity due to chemotherapy has led to characterization of novel methods, including the exploitation of natural compounds, in combination therapies. Flavonoids are natural polyphenolic compounds that play protective roles against tumor cell development. The focus of this study was apoptotic effects of two flavonoids, eupatorin and salvigenin, in combination with doxorubicin on a cellular model of colon cancer. Method: Upon establishing a non-effective dose of doxorubicin, and effective doses of eupatorin (100μM) and salvigenin (150μM) via MTT, morphological features of apoptosis were distinguished using DAPI staining and cell cycle blockage in the sub-G1 phase. Apoptosis was determined by annexin/ PI and western blotting. ROS levels and MMP were measured to show any role of mitochondria in apoptosis. Results: Co-administration of flavonoids with doxorubicin induced apoptosis via the mitochondrial pathway as mitochondrial membrane potential and ROS production were changed. Annexin/PI analysis demonstrated that apoptosis frequency was increased with the combination treatments in colon cancer cells. Finally, the combination of these flavonoids with doxorubicin increased the Bax/Bcl-2 ratio, caspase-3 expression and PARP cleavage. Conclusion: Combination of flavonoids with doxorubicin induces apoptosis and enhances effect on cancer cells which might allow amelioration of side effects by dose lowering.  相似文献   
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Objective: Hypertension (HTN) is one of the most important public health problems in the world. Lifestyle modification including dietary changes such as following the Dietary to Stop Hypertension (DASH) plan is the first step to control HTN. The aim of the present study was to identify perceived barriers to following dietary recommendations in hypertensive patients in Zanjan, Iran.

Materials and Methods: In this cross-sectional study, 200 outpatients (161 women, 39 men) with essential HTN (systolic blood pressure [SBP] ≥ 140 mmHg and diastolic blood pressure [DBP] ≥ 90 mmHg) were recruited from August to November 2012. A 29-item structured questionnaire was designed to assess perceived barriers to follow dietary recommendations. Validity and reliability were assessed by content validity index, content validity ratio, and Chronbach's alpha, respectively. An exploratory factor analysis with a principal component analysis extraction method and varimax rotation was performed to extract the underlying factors.

Results: Mean age and body mass index (BMI) of participants were 46.9 ± 5.5 years and 30.6 ± 3.6 kg/m2, respectively. The exploratory factor analysis extracted 6 interpretable factors with eigenvalue > 1. In order of importance, they were social and environmental barriers (eigenvalue = 2.489), social gathering (eigenvalue = 2.379), compliance with recommended diet and preference of other family members (eigenvalue = 2.127), palatability of the recommended diet (eigenvalue = 1.972), emotional statues and psychological factors (eigenvalue = 1.921), and cost (eigenvalue = 1.845). Mentioned factors explained 44% of the total variance.

Conclusion: Patients with HTN in our study perceived some barriers to following the recommended diet. In nutritional counseling, considering these barriers may be effective in improving the dietary adherence level in hypertensive patients.  相似文献   

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Nevus lipomatosus cutaneous superficialis (NLCS) is a rare malformation characterized by ectopic adipose tissue in the dermis. The lesion is usually present from birth or noticed in the first 2 decades of life. It occurs as sessile or pedunculated, domed nodular growths with a smooth, wrinkled, or cerebriform surface. Multiple lesions have a marked predilection for the gluteal region, lower back, and upper thigh, though solitary lesions may occur at unusual sites like the scalp, clitoris, and calf. An unusal case of NLCS is presented here where the solitary lesion occurred as a large exophytic growth arising at the groin in the fifth decade of life.  相似文献   
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