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81.
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Age is the main clinical determinant of large artery stiffness. Central arteries stiffen progressively with age, whereas peripheral muscular arteries change little with age. A number of clinical studies have analyzed the effects of age on aortic stiffness. Increase of central artery stiffness with age is responsible for earlier wave reflections and changes in pressure wave contours. The stiffening of aorta and other central arteries is a potential risk factor for increased cardiovascular morbidity and mortality. Arterial stiffening with aging is accompanied by an elevation in systolic blood pressure (BP) and pulse pressure (PP). Although arterial stiffening with age is a common situation, it has now been confirmed that older subjects with increased arterial stiffness and elevated PP have higher cardiovascular morbidity and mortality.

Increase in aortic stiffness with age occurs gradually and continuously, similarly for men and women. Cross-sectional studies have shown that aortic and carotid stiffness (evaluated by the pulse wave velocity) increase with age by approximately 10% to 15% during a period of 10 years. Women always have 5% to 10% lower stiffness than men of the same age.

Although large artery stiffness increases with age independently of the presence of cardiovascular risk factors or other associated conditions, the extent of this increase may depend on several environmental or genetic factors. Hypertension may increase arterial stiffness, especially in older subjects. Among other cardiovascular risk factors, diabetes type 1 and 2 accelerates arterial stiffness, whereas the role of dyslipidemia and tobacco smoking is unclear. Arterial stiffness is also present in several cardiovascular and renal diseases. Patients with heart failure, end stage renal disease, and those with atherosclerotic lesions often develop central artery stiffness. Decreased carotid distensibility, increased arterial thickness, and presence of calcifications and plaques often coexist in the same subject. However, relationships between these three alterations of the arterial wall remain to be explored.  相似文献   

83.
AIM: The purpose of our study was to assess the different effectiveness of Troxerutin in association with Pycnogenol compared to the effects obtainable with the same pharmacological principle in monotherapy in patients suffering from venous insufficiency. METHODS: Seventy patients with venous insufficiency of the lower extremities at the first stages of the CEAP classification (Cs1,3; Es; As 1; invalidity score 2, clinical score 1-2) were selected and subdivided into 2 groups: one of 50 and one of 20. All patients reported the following symptoms either associated or in isolation: heaviness, cramps, pruritus and pain at palpation. Evaluation of the degree of venous insufficiency was carried out by means of echo-Doppler at recruitment. The 1st group received Troxerutin (470 mg) associated with Pycnogenol (20 mg) in a dose of 1 g/day per os for 60 days; the 2nd group Troxerutin alone (300 mg) in a dose of 2 tablets twice a day per os for 60 days. Controls were set up at 30 and 60 days from the start of treatment and after a period of 3 months from the end of treatment to assess the effects on the symptomatology over time. The effectiveness of the drugs on symptomatology reported by both groups was assessed by means of an analysis of the qualitative variation of the symptoms using the score-scales method: 3=severe; 2=moderate; 1=slight; 0=absent and this variation was expressed as a percentage decrease and analysed using Student's test. RESULTS: The results of our study after 30 days of treatment highlighted a clinical improvement in all patients with the disappearance of symptoms (score from 3 to 1) in 50% of patients in the 1st group and in 35% in the 2nd with a peak of 96% in patients of the 1st group and 80% in the 2nd at the end of treatment (60 days). This result held stable in the course of follow-up for 96% of patients in the 1st group (p<0.001) and for 50% of those in the 2nd group (p<0.005). CONCLUSION: Comparison between the 2 groups showed that the group which received Troxerutin associated with Pycnogenol reported greater therapeutic effectiveness than the control group as regards both the rapidity of disappearance of the symptoms and as regards maintenance of the cure obtained.  相似文献   
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Ovarian histology and function after total abdominal hysterectomy   总被引:8,自引:0,他引:8  
Ovarian histology and function were assessed before and after total abdominal hysterectomy in 25 patients with symptomatic uterine myomata. Immediately before hysterectomy, bilateral ovarian biopsies were performed, and, 12 months later, all patients underwent a second ovarian biopsy through laparoscopy. Histologic study of the ovaries one year after total abdominal hysterectomy showed stromal cell hyperplasia, thickening of the tunica albuginea, and a significant decrease of follicular reserve, follicular cysts, and corpora albicantia. There was no significant difference in the number of atretic follicles and corpora lutea. The serum levels of all hormones studied were unchanged 12 months after the surgical procedures.  相似文献   
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The majority of patients with primary of metastatic hepatic tumors are not candidates for resection, because of tumor size, location near major intrahepatic blood vessels precluding a margin-negative resection, multifocality, or inadequate hepatic function related to coexistent cirrhosis. Radiofrequency ablation (RFA) is an evolving technology being used to treat patients with unresectable primary and metastatic hepatic cancers. RFA produces coagulative necrosis of the tumor through local tissue heating. Liver tumors are treated percutaneously, laparoscopioally, or during laparotomy, using ultrasonography to identify tumors and to guide placement of the RFA needle electrode. For tumors smaller than 2.0 cm in diameter, one or two deployments of the monopolar multiple-array needle electrode are sufficient to produce complete coagulative necrosis of the tumor. However, with increasing size of the tumor, there is a concomitant increase in the number of deployments of the needle electrode and the overall time necessary to produce complete coagulative necrosis of the tumor. In general, RFA is a safe, well-tolerated, effective treatment for unresectable hepatic malignancies less than 6.0 cm in diameter. Effective treatment of larger tumors awaits the development of more powerful, larger array monopolar and bipolar RFA technologies. Received: January 7, 2002  相似文献   
89.
OBJECTIVE: To assess the natural story of HIV-associated affective and cognitive disorders and the relationship with clinical, pharmacological, immunological and behavioural factors. METHOD: A total of 395 HIV-positive patients, naive to Highly Active Antirectroviral therapy (HAART), with no severe psychiatric disorders have been enrolled in the Neuro-ICONA Study. All participants were administered a comprehensive data collection instrument including an addiction behaviour survey, a medical problem list, a psychiatric assessment, a validated neuropsychological test battery. RESULTS: The global prevalence of cognitive impairment and of prominent depressive symptomatology were 17.9 and 15.5%, respectively. A significant difference in the prevalence of prominent depressive symptomatology was observed between patients in HAART and those not taking HAART(14.1 vs. 23.8%; P = 0.05). CONCLUSION: Depressive and cognitive disorders affect a substantial proportion of HIV-seropositive subjects. The prevalence of prominent depressive symptomatology appears to significantly vary in relationship to the therapeutic protocol.  相似文献   
90.
PURPOSE: To assess the value of MRI performed with phased-array coil in the diagnosis and preoperative staging of perianal and anal fistulas. MATERIALS AND METHODS: 20 patients (13 with Crohn's disease) with clinical evidence or suspicion of anal fistulas underwent pelvic MRI (1.5 T) performed with phased-array coil. Images were obtained in the axial and coronal planes using TSE T2-weighted high resolution sequences with and without fat suppression, T2-weighted HASTE and T1-weighted FLASH sequences, with and without fat suppression, before and after gadolinium enhancement. The following parameters were considered: presence of a fistula and relation with the sphincters, and presence of abscesses or complications. All patients underwent surgery. The MRI and surgical findings were assessed using the Park's fistula-in-ano classification and the St. James MR imaging classification of perianal fistulas. Surgery was considered the gold standard. RESULTS: MRI documented no evidence of fistula in 2 patients, intersphinteric fistulas in 5 (grade 1 and 2 St. James), trans-sphincteric fistulas in 9 (grade 3 and 4 St. James), translevator in 2 (grade 5) and complex ano-rectum-vaginal fistulas in 2. Concordance with surgery was 90%. CONCLUSIONS: MRI is an accurate technique for the identification and classification of anal and perianal fistulas and their complications. In our experience the phased-array coil offers both high field of view and spatial resolution, enabling the demonstration of perianal pathology.  相似文献   
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