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991.
992.
993.
Serum testosterone levels and arterial blood pressure in the elderly.   总被引:2,自引:0,他引:2  
The aim of this study was to evaluate the relationship between serum testosterone levels and arterial blood pressure (BP) in the elderly. We studied 356 non-diabetic, non-smoking, non-obese men aged 60 to 80 years and untreated for hypertension. All subjects were evaluated in the morning after an overnight fast. Evaluation included measurements of the following: BP (by mercury sphygmomanometer, Korotkoff I and V), body weight, height and free testosterone (T) plasma levels (by radioimmunoassay). According to the BP values, the subjects were classified as normotensives (NT; n=112; SBP/DBP<140/90 mmHg), systolic and diastolic hypertensives (HT; n=127; SBP/DBP>140/90 mmHg), and isolated systolic hypertensives (ISH; n=117; SBP>140 mmHg and DBP<90 mmHg). T values decreased with increasing age in all 3 groups and was significantly lower in HT (-15%) and ISH men (-21%) than in NT men (p<0.05). In each group, the T levels showed a highly significant negative correlation with BMI (p<0.001). A significant negative correlation was also found between T levels and SBP in NT (r=-0.35, p<0.001), ISH (r=-0.67, p<0.001), and HT (r=-0.19, p<0.05) men, whereas a negative correlation with DBP was observed only in the NT men (r=-0.19, p<0.05). Adjusting for the BMI confirmed a significant difference in plasma T levels between ISH and NT men, but not between HT and NT men. Multiple regression analysis employing BP as a dependent variable confirmed a strong relationship between T levels and SBP in all 3 groups, whereas a significant relationship between T levels and DBP was found only in NT men. In conclusion, although further studies are needed to clarify the relationship between plasma T levels and BP, our findings suggest that in elderly men with ISH, the reduced plasma levels of testosterone might contribute to the increased arterial stiffness typical of these subjects.  相似文献   
994.
In this final of a 5-part Focus Seminar series on precision medicine, we focus on catecholaminergic polymorphic ventricular tachycardia (CPVT). This focus on CPVT allows us to take a “deep dive” and explore the full extent of the precision medicine opportunities for a single cardiovascular condition at a level that was not possible in the preceding articles. As a new paradigm presented in this article, it has become clear that CPVT can occur as either a typical or atypical form. Although there is a degree of overlap between the typical and atypical forms, it is notable that they arise due to different underlying genetic changes, likely exhibiting differing mechanisms of action, and presenting with different phenotypic features. The recognition of these differing forms of CPVT and their different etiologies and mechanisms is an important step toward implementing rapidly emerging precision medicine approaches that will tailor novel therapies to specific gene defects.  相似文献   
995.
Risk of Second Cancers in Patients with Colorectal Carcinoids   总被引:10,自引:0,他引:10  
INTRODUCTION: It is often stated that patients with colorectal carcinoid tumors have an increased risk of developing other malignancies. However, this risk has not been conclusively documented. A comprehensive evaluation is needed to more thoroughly assess the risk of second cancers in patients with colorectal carcinoids. METHODS: A search of the National Cancer Institute Surveillance, Epidemiology, and End Result database from 1973 to 1996 revealed 2,086 patients with colorectal carcinoids. This subset of patients was examined for occurrence of second cancers. The observed incidence of cancer for each site was compared with the expected incidence based on the gender-adjusted and age-adjusted cancer rates in the remaining Surveillance, Epidemiology, and End Result file. A Poisson distribution probability was used to determine the significance of these comparisons. RESULTS: Patients with colorectal carcinoids had an increased rate of cancer in the colon and rectum (P < 0.001), small bowel (P < 0.001), esophagus/stomach (P = 0.02), lung/bronchus (P < 0.001), urinary tract (P = 0.005), and prostate (P < 0.001), when compared with a control population. Most of the gastrointestinal tract cancers were synchronous cancers, whereas lesions outside the gastrointestinal tract were most commonly metachronous tumors. CONCLUSIONS: A significantly increased risk of synchronous colorectal, small-bowel, gastric, and esophageal cancers and metachronous lung, prostate, and urinary tract neoplasms is clearly demonstrated. After the diagnosis of colorectal carcinoid tumors, patients should undergo appropriate screening and surveillance for cancer at these sites.  相似文献   
996.
The aquatic ecosystem is the natural habitat of microorganisms including Vibrio and Aeromonas genus which are pathogenic to human and animals. In the present investigation the frequency of these bacteria and the enzymatic characteristics of 34 Vibrio alginolyticus strains isolated from bivalves harvested in Venice Lagoon (Italy) and Guanabara Bay (Brazil) were carried out from November 2003 to February 2004. The mussels' samples were submitted to enrichment in Alkaline Peptone Water (APW) added with 1% of sodium chloride (NaCl) and APW plus 3% NaCl incubated at 37 degrees C for 18-24 h. Following the samples were streaked onto TCBS Agar (Thiossulfate Citrate Bile Sucrose Agar) and the suspected colonies were submitted to biochemical characterization. Also, the Vibrio alginolyticus strains were evaluated to collagenase, elastase and chondroitinase production. The results showed the isolation of 127 microorganisms distributed as follows: 105 Vibrio strains such as V. alginolyticus (32.4%), V. harveyi (19%) and V. parahaemolyticus (7.6%), 20 Aeromonas strains and two Plesiomonas shigelloides were the main pathogens isolated. We observed the production of the three enzymes from V. alginolyticus strains considered as the main virulence factors of the bacteria, especially in cases of human dermatological infection.  相似文献   
997.

Purpose

“Endometriosis” is defined such as the presence of endometrial glands and stroma outside the uterine cavity. This ectopic condition may develop as deeply infiltrating endometriosis (DIE) when a solid mass is located deeper than 5 mm underneath the peritoneum including the intestinal wall. The ideal surgical treatment is still under search, and treatment may range from simple shaving to rectal resection. The aim of the present systematic review is to report and analyze the postoperative outcomes after rectosigmoid resection for endometriosis.

Methods

We performed a systematic review according to Meta-analysis of Observational Studies in Epidemiology guidelines. The search was carried out in the PubMed database, using the keywords: “rectal resection” AND “endometriosis” and “rectosigmoid resection” AND “endometriosis.” The search revealed 380 papers of which 78 were fully analyzed.

Results

Thirty-eight articles published between 1998 and 2017 were included. Three thousand seventy-nine patients (mean age 34.28?±?2.46) were included. Laparoscopic approach was the most employed (90.3%) followed by the open one (7.9%) and the robotic one (1.7%). Overall operative time was 238.47?±?66.82. Conversion rate was 2.7%. In more than 80% of cases, associated procedures were performed. Intraoperative complications were observed in 1% of cases. The overall postoperative complications rate was 18.5% (571 patients), and the most frequent complication was recto-vaginal fistula (74 patients, 2.4%). Postoperative mortality rate was 0.03% and mean hospital stay was 8.88?±?3.71 days.

Conclusions

Despite the large and extremely various number of associated procedures, rectosigmoid resection is a feasible and safe technique to treat endometriosis.
  相似文献   
998.
OBJECTIVES: The aim of this study was to evaluate whether the occurrence of the Brugada Syndrome typical electrocardiogram (ECG) pattern (i.e., right bundle branch block, coved-type ST-segment elevation, and T-wave inversion in the right precordial leads) is characterized by a concomitant lengthening of QT intervals in the right precordial leads. BACKGROUND: It has been suggested that the typical ECG pattern of Brugada syndrome is due to a decreased net inward current during phase 1 of the action potential, which also leads to its prolongation in the right epicardium. METHODS: Thirty-two subjects (19 males) age 37 +/- 15 years with a suspicious baseline ECG, or who were relatives of Brugada syndrome patients, underwent 12-lead ECG before and after the administration of flecainide. RESULTS: The flecainide test was negative in 14 and positive in 18 subjects. After flecainide administration, the positive ECGs were characterized by a greater QT interval corrected for heart rate (QTc) prolongation in the right precordial leads than that in the negative ECGs (78.2 +/- 35.5 ms vs. 22.0 +/- 28.4 ms in V(1) and 107.1 +/- 43.8 ms vs. 26.7 +/- 30.1 ms in V(2); p < 0.01), whereas there was no difference in the QTc prolongation in the left precordial leads (55.2 +/- 25.3 ms vs. 35.1 +/- 28.1 ms in V(5) and 53.1 +/- 32.8 ms vs. 27.3 +/- 22.4 ms in V(6); p = NS). CONCLUSIONS: In accordance with the electrophysiological background, the typical ECG pattern of Brugada syndrome is also characterized by a considerable prolongation of the QT interval in right precordial leads.  相似文献   
999.
BACKGROUND: In the absence of evidence-based data, the optimal antithrombotic treatment after coronary artery stenting in patients on chronic oral anticoagulation (OAC) remains unknown. In order to investigate current practice in this setting, an international survey was carried out. METHODS: A questionnaire was e-mailed to 40 internationally renowned, foreign Interventional Centers worldwide. RESULTS: Out of the 24 Centers (60%) replying, only in 13 (54%) is antithrombotic treatment carried out in accordance with a standardized protocol. OAC is stopped in favor of aspirin plus ticlopidine/clopidogrel in selected (low thromboembolic risk) conditions in 13 (54%) Centers. When OAC is continued, the association with a single antiplatelet is employed in a few Centers only, as opposed to triple antithrombotic treatment (OAC and aspirin plus ticlopidine/clopidogrel) which is adopted, selectively or systematically, in the majority (83%) of Centers. In 8 (33%) Centers adopting triple antithrombotic treatment, the dose of OAC is decreased in all patients, whereas in 9 (38%) it is left unchanged. Upon completion of 1 to 3-6 months of antithrombotic treatment with OAC and single/dual antiplatelets, in 9 (38%) Centers this regimen is continued indefinitely, whereas in 10 (41%) antiplatelets are systematically withdrawn. Out of the 13 Centers, selectively exchanging OAC for aspirin plus ticlopidine/clopidogrel, low- or full-dose low-molecular-weight heparin is added in selected (high thromboembolic risk) cases in 3 (23%) and 5 (38%) Centers, respectively. Following 1 to 3-6 months of aspirin plus ticlopidine/clopidogrel antithrombotic treatment, OAC is resumed in all cases in 9 (69%) Centers and in no cases in 1 (8%). CONCLUSIONS: Our survey shows a high variability in the current antithrombotic treatment of patients on chronic OAC undergoing coronary artery stenting. Although various regimens may be adopted, the optimal antithrombotic treatment for this patient subset still needs to be identified.  相似文献   
1000.
Oral glutamine challenge is a method to increase blood ammonia and may be used to study the ammonia lowering effect of drugs potentially useful in hepatic encephalopathy (HE). We tested its influence on the psychometric performance of 18 cirrhotic patients without HE. Twelve nonencephalopatic cirrhotic patients were studied before and after glutamine load (20 g in 100 mL tap water) and six patients before and after placebo (100 mL tap water) by using the Number Connection Test (NCT), the Covert Visual Attention Orienting Test (CVAOT), and the Scan Test (SCT). Blood ammonia increased significantly after glutamine (from 79 ± 34 to 211 ± 66 g/dL) but not after placebo (from 94 ± 41 to 88 ± 26). No difference in the NCT was found before and after glutamine load or placebo. The CVAOT was similar after glutamine challenge and placebo, nor any interaction between Loads (glutamine or placebo) × Cue position was found, suggesting that glutamine load did not influence attention-orienting. SCT results were also similar after glutamine and placebo, suggesting a lack of influence on the working memory. Glutamine challenge is a safe method to induce hyperammonemia in nonencephalopatic cirrhotic patients and, therefore, to study the efficacy of ammonia lowering treatments.  相似文献   
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