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101.
Background. Patients with degenerative aortic stenosis (AS) exhibit elevated prevalence of coronary artery disease (CAD) and internal carotid artery stenosis (ICAS). Our aim was to investigate prevalence of significant CAD and ICAS in relation to demographic and cardiovascular risk profile among patients with severe degenerative AS.Methods. We studied 145 consecutive patients (77 men and 68 women) aged 49-91 years (median, 76) with severe degenerative AS who underwent coronary angiography and carotid ultrasonography in our tertiary care center. The patients were divided into two groups according to the presence of either significant CAD (n=86) or ICAS (n=22).Results. The prevalence of significant CAD or ICAS was higher with increasing number of traditional risk factors (hypertension, hypercholesterolemia, diabetes, smoking habit) and decreasing renal function. We found interactions between age and gender in terms of CAD (p=0.01) and ICAS (p=0.06), which was confirmed by multivariate approach. With the reference to men with a below-median age, the prevalence of CAD or ICAS increased in men aged >76 years (89% vs. 55% and 28% vs. 14%, respectively), whereas the respective percentages were lower in older vs. younger women (48% vs. 54% and 7% vs. 17%).Conclusions. In severe degenerative AS gender modulates the association of age with coronary and carotid atherosclerosis with its lower prevalence in women aged >76 years compared to their younger counterparts. This may result from a hypothetical “survival bias”, i.e., an excessive risk of death in very elderly women with severe AS and coexisting relevant coronary or carotid atherosclerosis.  相似文献   
102.
Aging is an unavoidable fate that afflicts all life, during this process in mammals reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. Therefore, the maintenance of antioxidant homeostasis is an important anti-aging strategy for skin. Nature has excellent anti-aging remedies that act externally as well as internally to delay the visual signs of aging. In view of this fact, the present study investigates the in vitro anti-aging activity of five medicinal plants belonging to phenolic rich families namely Rosmarinus officinalis, Lavandula officinalis, Matricaria chamomilla, Camellia sinensis and Pelargonium graveolens. The selected plants are those most frequently used in the preparation of ethnomedicinal recipes for the prevention or treatment of aging. The inhibitory effects of the ethanolic and aqueous extracts of the five selected plants on the activity of tyrosinase, elastase, and collagenase enzymes were investigated. Furthermore, the chemical composition of the plants and the antioxidant capacity of their extracts were assessed. The results showed that R. officinalis had the highest total phenolics content which was correlated with its potent antioxidant and anti-aging activities. To pinpoint the active metabolites in the tested extracts, we evaluated the metabolite variations using ultra-performance liquid chromatography coupled with high resolution electrospray ionization-tandem mass spectrometry (UPLC-HR-ESI-MS/MS). Multivariate data analysis (MVDA) revealed that R. officinalis significantly accumulated metabolites from the aromatic diterpenoid, flavonoid and phenolic acid classes. These results indicate that rosemary can be used for further development of topical preparations with anti-aging properties.

Aging is an unavoidable fate that afflicts all life, during this process in mammals, reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging.  相似文献   
103.
ObjectivesTo compare the amount of en-masse retraction with or without piezocision corticotomy, to assess the type of tooth movement, to evaluate root integrity after retraction, and to record reported pain levels.Materials and MethodsThis randomized, controlled clinical trial included 26 orthodontic patients requiring premolar extraction. The patients were divided into two groups: (1) an extraction with piezocision corticotomy group (PCG) and (2) an extraction-only group, which served as the control group (CG). Cone-beam computed tomography images were acquired before and 4 months after the initiation of en-masse retraction utilizing miniscrews. The following variables were assessed: the amount of en-masse retraction, incisor inclination, incisor and canine root resorption, and patient-reported pain.ResultsTwelve and 11 participants completed the entire study in the PCG and CG, respectively. The amount of en-masse retraction was significantly greater in the PCG compared to the CG (mean = 4.8 ± 0.57 mm vs 2.4 ± 0.33 mm, respectively [P < .001]). There was also significantly less tipping and root resorption of incisors in the PCG (P < .05). The reported pain was significantly higher on the first day in the PCG compared to the CG (P < .001); however, it became similar between the groups after 24 hours.ConclusionsPiezocision corticotomy enhanced the amount of en-masse retraction two times more with less root resorption. However, future studies are required to assess the long-term effects of this technique.  相似文献   
104.
The International Journal of Cardiovascular Imaging - Abnormal atrial mechanics in biventricular circulations have been associated with elevated left heart filling pressures. Similar associations...  相似文献   
105.
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107.
Automated Implantable Cardioverter Defibrillators (AICD), simply known as an Implantable Cardioverter Defibrillator (ICD), has been used in patients for more than 30 years. An Implantable Cardioverter Defibrillator (ICD) is a small battery-powered electrical impulse generator that is implanted in patients who are at a risk of sudden cardiac death due to ventricular fibrillation, ventricular tachycardia or any such related event. Typically, patients with these types of occurrences are on anticoagulant therapy. The desired International Normalized Ratio (INR) for these patients is in the range of 2–3 to prevent any subsequent cardiac event. These patients possess a challenge to the dentist in many ways, especially during oral surgical procedures, and these challenges include risk of sudden death, control of post-operative bleeding and pain.This article presents the dental management of a 60 year-old person with an ICD and concomitant anticoagulant therapy. The patient was on multiple medications and was treated for a grossly neglected mouth with multiple carious root stumps. This case report outlines the important issues in managing patients fitted with an ICD device and at a risk of sudden cardiac death.  相似文献   
108.

Objective

This study aimed to evaluate stress patterns generated within implant-supported mandibular overdentures retained by two different attachment types: ball and socket and locator attachments.

Materials and methods

Commercial CAD/CAM and finite element analysis software packages were utilized to construct two 3D finite element models for the two attachment types. Unilateral masticatory compressive loads of 50, 100, and 150 N were applied vertically to the overdentures, parallel to the longitudinal axes of the implants. Loads were directed toward the central fossa in the molar region of each overdenture, that linear static analysis was carried out to find the generated stresses and deformation on each part of the studied model.

Results

According to FEA results the ball attachment neck is highly stressed in comparison to the locator one. On the other hand mucosa and cortical bone received less stresses under ball and socket attachment.

Conclusions

Locator and ball and socket attachments induce equivalent stresses on bone surrounding implants. Locator attachment performance was superior to that of the ball and socket attachment in the implants, nylon caps, and overdenture. Locator attachments are highly recommended and can increase the interval between successive maintenance sessions.  相似文献   
109.
Large bowel obstruction is a rare complication of gastrointestinal endometriosis. A 32-year-old female patient presented to the emergency department with complaints of diffuse abdominal pain and constipation for 10 days with progressive abdominal distention and vomiting. Plain abdominal x-ray showed grossly dilated large bowel up to the sigmoid colon with no gas in the rectum. Abdominal computed tomography revealed hugely dilated large bowel up to the sigmoid colon, with sigmoid soft tissue mass. Flexible sigmoidoscopy showed a non-ulcerating sigmoid mass, with complete obstruction of the sigmoid colon, which impeded the further advancement of the scope. She underwent exploratory laparotomy with provisional diagnosis of complete large bowel obstruction due to sigmoid tumor. Sigmiodectomy with end colostomy was performed. Histopathology revealed endometrial glands with stroma in muscularis properia of the sigmoid colon mass. Endometriosis should be considered in women of reproductive age presenting with symptoms of large bowel obstruction.Endometriosis is the presence of functional endometrial tissue outside the uterus, which affects up to 15% of childbearing age woman.1 It is an uncommon cause of large bowel obstruction.2 If large bowel obstruction occurs, it may be caused by luminal compression from a pelvic organ endometrioma, a fibrotic reaction resulting in stricture and adhesions, or swelling of endometriotic implants in the intestinal wall or a combination of these 3 mechanisms.3 Herein, a rare case of complete large bowel obstruction due to sigmoid colon endometriotic mass is presented in which the treatment was sigmoidectomy with end colostomy. A brief review of the literature pertaining to this condition is also presented. Our objective in presenting this case is to increase the awareness of physicians to the possibility of endometriosis as a differential diagnosis when assessing females of reproductive age who present with manifestations of intestinal obstruction.  相似文献   
110.

Objectives:

To explore the spectrum of pathologies diagnosed in prostatic biopsies of Saudi men, and test whether the frequency of diagnosing the malignant fraction has been changed over the last 15 years, and assess the association between chronic inflammation (CI) with both benign prostatic hyperplasia (BPH) and cancer (PCa), and investigate the histological findings of cases presented with acute urinary retention (AUR) clinically.

Methods:

This is a retrospective cohort study including all prostatic biopsies accessed in the files in the Surgical Pathology Laboratory of King Fahd University Hospital, Alkhobar, Kingdom of Saudi Arabia over 15 years (1999-2013) for Saudi men. Age, procedure indication, and final diagnoses were retrieved and slides were reviewed.

Results:

There were 360 cases included in this study with a median age of 65 year-old. The BPH comprised the most (64.7%), while PCa accounted for 89 cases, 13.5% of which were incidental. Most cases of both BPH and PCa were diagnosed in the seventh decade. The frequency of diagnosing PCa did not show a solid rise or fall over time. Chronic inflammation is more related to BPH than to PCa. Only CI showed a significant statistical association with AUR.

Conclusion:

Prostatic diseases show a stable trend over time. While CI is a common dominator for both BPH and PCa, it is associated more with BPH. Among all histological findings, only CI is related to the clinical presentation of AUR.The spectrum of prostatic diseases is a common health concern all over the world. While benign prostatic hyperplasia (BPH) is the most frequent urologic diagnosis in elderly males worldwide, affecting approximately one third of males in their 60’s,1,2 prostatic carcinoma (PCa) is the second most common cause of cancer-related death in males after lung cancer.3 The disease represents clear racial and national differences, with its highest incidence in blacks in the West, and lowest in Asian males.4 Recently, there has been a rising trend for PCa in populations that are thought to be of low risk.5 Furthermore, the relationship between chronic inflammation (CI) and presence and progression of both BPH and PCa is controversial.6-9 On the other hand, acute urinary retention (AUR), which is the most frequent emergency in urology, is mostly developed in a background of BPH.10 Whether other pathologies, such as CI and infarction increase the risk of this complication is debated.11-13 In this work, we retrospectively reviewed the whole spectrum of prostatic pathologies diagnosed in our center during the last 15 years, including prostatic intraepithelial neoplasia (PIN) and atypical small acinar proliferation (ASAP), and study various diseases in relation to age of diagnosis, explore the change in trend of diagnosing PCa over a period witness an increase in screening and gradual westernization of lifestyle, test the relationship between CI and both BPH and PCa, and also, we investigate the role of different biopsy findings in relation to the clinical presentation with AUR.  相似文献   
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