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121.
Risk factors for fracture of the neck of the femur are relatively well established, but those for fracture at other sites are little studied. In this large population study we explore the role of age, body mass index (BMI), and physical activity on the risk of fracture at seven sites in postmenopausal women. As part of the Million Women Study, 1,154,821 postmenopausal UK women with a mean age of 56.0 (SD 4.8) years provided health and lifestyle data at recruitment in 1996 to 2001. All participants were linked to National Health Service (NHS) hospital records for day‐case or overnight admissions with a mean follow‐up of 11 years per woman. Adjusted absolute and relative risks for seven site‐specific incident fractures were calculated using Cox regression models. During follow‐up, 4931 women had a fracture of the humerus; 2926 of the forearm; 15,883 of the wrist; 9887 of the neck of the femur; 1166 of the femur (not neck); 3199 a lower leg fracture; and 10,092 an ankle fracture. Age‐specific incidence rates increased gradually with age for fractures of forearm, lower leg, ankle, and femur (not neck), and steeply with age for fractures of neck of femur, wrist, and humerus. When compared to women with desirable BMI (20.0 to 24.9 kg/m2), higher BMI was associated with a reduced risk of fracture of the neck of femur, forearm, and wrist, but an increased risk of humerus, femur (not neck), lower leg, and ankle fractures (p < 0.001 for all). Strenuous activity was significantly associated with a decreased risk of fracture of the humerus and femur (both neck and remainder of femur) (p < 0.001), but was not significantly associated with lower leg, ankle, wrist, and forearm fractures. Postmenopausal women are at a high lifetime risk of fracture. BMI and physical activity are modifiable risk factors for fracture, but their associations with fracture risk differ substantially across fracture sites. © 2016 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR)  相似文献   
122.
The purpose of the study was to assess at rest and during exercise total sympathetic activity, as expressed by plasma cyclic AMP (cAMP) blood levels and sinus node activity (SNA), as well as atrial natriuretic factor (ANF) blood levels in VVI and DDD pacing with long and short atrioventricular delays in DDD paced patients suffering from complete heart block. Clinical parameters, such as exercise time, and arterial blood pressure (ABP) were also taken into consideration. Thirteen patients (six males, mean age 65 +/- 2 years), were examined randomly in VVI and DDD pacing with 100 and 150 ms atrioventricular delays (AVD). Plasma cAMP and ANF were measured at rest, at peak exercise and 15 and 30 min after the test. The cAMP at rest remained unchanged whatever the pacing mode or the AVD, but 30 min after exercise, the cAMP levels were statistically lower in DDD pacing with short AVD (100 ms) than in DDD with long AVD (150 ms) or VVI pacing (cAMP DDD/100 ms: 16 +/- 0.8 pmol.ml-1, cAMP DDD/150 ms: 20 +/- 2 pmol.ml-1, P < 0.01, cAMP VVI: 29 pmol.ml-1, P < 0.001). ANF plasma levels at rest were significantly higher in VVI pacing than in DDD modes, with either long or short AVD (ANF DDD/100 ms: 93 +/- 10 pg.ml-1, ANF DDD/150 ms: 100 +/- 13 pg.ml-1, ANF VVI: 150 +/- 16 pg.ml-1, P < 0.001, P < 0.03 respectively compared to VVI).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
123.
Background:  An improved light activated disinfection technique utilizing a specific photosensitizer formulation, liquid optical-conduit, oxygen-carrier and light energy of appropriate wavelength has been introduced recently. This study tested the efficacy of this improved light activated disinfection on ex vivo biofilms of Enterococcus faecalis at two different stages of maturation.
Methods:  Eighty-five tooth sections were prepared and endodontic biofilm of E. faecalis were grown within the root canal. In stage 1, conventional light activated disinfection (LAD), chemical disinfectant (sodium hypochlorite) and improved LAD were tested on four-day-old (immature) biofilms. In stage 2, conventional LAD, improved LAD and chemomechanical disinfection (alone and in combination with improved LAD) were tested on four-week-old (mature) biofilms.
Results:  Sodium hypochlorite and improved LAD showed the ability to significantly inactivate bacteria in four-day-old biofilms when compared to the control and LAD (p < 0.05). Inactivation of bacteria from deeper dentine was higher in improved LAD than sodium hypochlorite. In four-week-old biofilms, a combination of chemomechanical disinfection and improved LAD produced significant bacterial killing compared to either chemomechanical disinfection or improved LAD alone.
Conclusions:  This study highlighted the potential of improved LAD to kill bacteria within dentinal tubules. In combination with chemomechanical preparation, the improved LAD significantly inactivated four-week-old biofilm bacteria.  相似文献   
124.

Background  

There is currently a trend towards unsafe unprotected anal intercourse (UAI) among men who have sex with men. We evaluated a short individual counselling session on reducing UAI among gay and bisexual men.  相似文献   
125.
In the last few years, transcatheter aortic valve implantation (TAVI) has become an alternative procedure in patients with severe aortic stenosis and high risk for surgical aortic replacement. Due to the anatomic correlation between aortic valve structure and conduction system of the heart, one of the most common complications after TAVI is conduction system disturbances which including bundle branch block, complete heart block and need for permanent pacemaker implantation. Although these disturbances are usually not lethal, they may have a great influence on patients’ state and long term-survival. Several risk factors for conduction disturbances have been identified which including age, anatomy of the heart, periprocedural factors, type of implanted valve, preexisting abnormalities and comorbidities. As this technique becomes more familiar to physicians, patients should be carefully screened for risk factors for the development of conduction abnormalities after TAVI in order to provide effective prevention and proper treatment.  相似文献   
126.
Syncope in patients with advanced heart failure is a sign of poor prognosis. The cause of syncope in patients with dilated cardiomyopathy (DC) is not fully recognized and may remain elusive even after standardized evaluation. The purpose of the present study was to examine the implication of neurally mediated mechanisms in the pathophysiology of syncopal episodes in patients with DC. Twenty-six patients (21 men, 5 women; mean age 59 +/- 2 years, range 38 to 79) with DC and left ventricular ejection fractions 相似文献   
127.
BACKGROUND: Cardiac resynchronization therapy (CRT) pacing has been proposed as an additional treatment to medical therapy to improve heart failure patients with left ventricular asynchrony. The aim of this study was to evaluate the influence of CRT treatment on proinflammatory cytokines in patients with heart failure. METHODS: Twenty patients, with a mean age 64 +/- 2 years, with severe chronic heart failure NYHA class II-IV (mean ejection fraction 25 +/- 2%), were included in the study. Patients were treated with CRT pacing, after failure of optimal therapy. Blood samples were taken at baseline, 3 months after pacing therapy, and after a subsequent 3-month period of no pacing for the assessment of proinflammatory cytokines TNF-alpha and its receptors (sTNFR-I, sTNFR-II), IL-6, adhesion molecules sICAM-1 and sVCAM-1, and the apoptotic indices sFas and sFas-Ligand. RESULTS: Levels of TNF-alpha, sTNFR-I, and sTNFR-II were reduced at the end of 3 months of CRT therapy and further reduced at the end of the no pacing period (P < 0.05, compared to baseline). Levels of IL-6 also declined after 3 months of CRT pacing (from 8.9 +/- 2.5 pg/mL to 4.7 +/- 1.3 pg/mL, P < 0.05) and this was maintained during the no pacing period (3.9 +/- 1.1 pg/mL P < 0.05 compared to baseline). The adhesion molecule sICAM-1 levels also reduced (from 265 +/- 17 ng/mL to 235 +/- 12, P < 0.05) after 3 months of CRT pacing and remained unchanged at the end of the no pacing period (219 +/- 12 ng/mL, P < 0.05 compared to baseline values). CONCLUSION: Major proinflammatory cytokines and the adhesion molecule sICAM-1 are reduced with CRT therapy and this effect is maintained for at least 3 months after discontinuation of pacing.  相似文献   
128.
Miles  LA; Levin  EG; Plescia  J; Collen  D; Plow  EF 《Blood》1988,72(2):628-635
Endothelial cells are centrally involved in regulation of fibrinolysis, and receptors for plasminogen and urokinase provide a mechanism by which cells can regulate their fibrinolytic function. Therefore, the existence and characteristics of receptors for these fibrinolytic components on cultured human umbilical vein endothelial cells were examined. We verified the presence of plasminogen receptors on these cells (Kd = 2.1 +/- 1.3 mumol/L, and 1.8 +/- 1.3 x 10(7) binding sites/cell). These binding parameters and other characteristics indicate that these receptors are closely related to the plasminogen receptors on many circulating and adherent cells. Specific binding sites that interact with two-chain urokinase of mol wt 55,000 with a dissociation constant of 2.1 +/- 1.7 nmol/L, with 2.9 +/- 2.9 x 10(5) sites/cell were also identified. Single-chain urokinase of mol wt 55,000, but not the two-chain degradation product of mol wt 33,000 bound to the cells, implicating the amino-terminal aspects of the ligand in receptor recognition. When endothelial cells were stimulated with thrombin, an agent that modulates their fibrinolytic potential, both receptor types were modestly affected; urokinase binding increased 17%, whereas plasminogen binding decreased 19%. The presence and modulation of plasminogen and urokinase receptors provide a potentially important additional mechanism by which endothelial cells may regulate fibrinolysis.  相似文献   
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