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71.
C G Arruda J M Aldrighi L A Bortolotto I N Alecrin J A F Ramires 《Gynecological endocrinology》2006,22(10):557-563
BACKGROUND: Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries. OBJECTIVES: To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate. SUBJECTS: Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III). METHODS: Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment. RESULTS: After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively). CONCLUSIONS: PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate. 相似文献
72.
Jonathan Larkin Anne Bost John I Glass Seng-Lai Tan 《Journal of interferon & cytokine research》2006,26(12):854-865
Hepatitis C virus (HCV)-specific impairments in host immunity have been described at multiple levels of the innate and adaptive response, which may lead to viral persistence in the majority of infections. Understanding of HCV-associated immune defects could lead to novel therapeutic advances. Natural killer (NK) cells, the major effector cells of the innate immune system, are functionally impaired in chronic HCV infection. It has been suggested that this phenotype is a result of virus-specific defects in antigen-presenting cells (APCs) that regulate NK cell activity, as normal NK function is restored when they are stimulated ex vivo. In this study, we used human NK cell cytotoxicity assays to evaluate the activation-induced effects of NK cells on the HCV replicon-containing hepatic cells. We found that cytokine-activated NK cells were capable of inducing an HCV-associated, perforin/granzyme-dependent lysis of human hepatoma cells and that this required direct cellular contact and was independent of MHC class I expression levels. In contrast, on removal of cytokine stimulation, NK cells failed to exert any direct cytolytic effect on replicon targets. These findings suggest an important underlying mechanism by which NK cells control HCV infection and, with appropriate understanding of HCV-associated immune defects, could lead to novel therapeutic advances. 相似文献
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15 Years in surgical management of pulmonary hydatidosis. 总被引:1,自引:0,他引:1
Raafat I Shalabi Adel K Ayed Morsi Amin 《Annals of thoracic and cardiovascular surgery》2002,8(3):131-134
OBJECTIVES: Echinococcosis remains an endemic surgical problem in countries where sheep and cattle raising is carried out, particularly in many Mediterranean countries. This study aims to evaluate the management of different presentations of pulmonary hydatidosis and their outcome over 15 years. DESIGN: Retrospective study.Setting: Thoracic surgical department, Chest Diseases Hospital, Kuwait. PATIENTS: Sixty patients operated upon for hydatid disease were evaluated pre- and post- operatively; 35 males, 25 females with a mean age of 28.4 years. Most patients were investigated by laboratory, serological and radiological studies. Different surgical techniques were used to remove the hydatid cyst from the lung. RESULTS: The most common presenting symptoms were cough (41 patients), and 12 patients were asymptomatic. Chest X-ray showed a rounded shadow in 42 patients; 19 cases were of vigorous size >10 cm. Thoracotomy was done in 57 patients; two chest wall cases were managed by minimal skin incision and enucleation, one hydatid cyst of the heart was approached through a median sternotomy. The mean hospital stay was 9 days. Postoperative complications occurred in 9 patients; prolonged air leak in 4 patients, pleural effusion in 3, pneumothorax, and wound infection in one patient each. One patient (65 years old) died on the 6th post-operative day most probably from pulmonary embolism. In a follow-up period of 2-15 years, 4 recurrences have been noted. CONCLUSION: Surgical excision of pulmonary hydatidosis with maximum preservation of the lung parenchyma is the main stay of treatment. 相似文献
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A. HAZIOT I. KATZ G. W. RONG X. Y. LIN J. SILVER & S. M. GOYERT 《Scandinavian journal of immunology》1997,46(3):242-245
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule. 相似文献