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991.
Mathew S Maurer Daniel Burkhoff Linda P Fried John Gottdiener Donald L King Dalane W Kitzman 《Journal of the American College of Cardiology》2007,49(9):972-981
OBJECTIVES: The purpose of this study was to evaluate left ventricular (LV) size and structure in elderly subjects with hypertension (HTN) and heart failure who have a normal ejection fraction (HFNEF) in a large population-based sample. BACKGROUND: The pathophysiology of HFNEF is incompletely understood but is generally attributed to LV diastolic dysfunction with normal or reduced LV diastolic chamber size despite greater than normal filling pressures. METHODS: In the Cardiovascular Health Study (n = 5,888), demographic and clinical characteristics and ventricular structure and function were compared in healthy normal subjects (healthy; n = 499), subjects with HTN but not heart failure (HTN; n = 2,184), and subjects with HTN and HFNEF (HFNEF; n = 167). RESULTS: Subjects with HFNEF were older, more obese, and more often African American than healthy and HTN subjects and had a higher prevalence of diabetes, coronary heart disease, and anemia than HTN subjects. Serum creatinine and cystatin-C were increased in HFNEF subjects. Average LV diastolic dimension was significantly increased in HFNEF subjects (5.2 +/- 0.8 cm) compared with healthy (4.8 +/- 0.6 cm) and HTN (4.9 +/- 0.6 cm) subjects. As a result, average calculated stroke volume (89 +/- 25 ml vs. 78 +/- 20 ml and 80 +/- 20 ml) and cardiac output (6.0 +/- 2.0 l/min vs. 4.8 +/- 1.3 l/min and 5.1 +/- 1.4 l/min) were increased in HFNEF compared with healthy and HTN subjects, respectively. CONCLUSIONS: As a group, HFNEF subjects have increased LV diastolic diameter and increased calculated stroke volume. They also have increased prevalence of multiple comorbidities, including anemia, renal dysfunction, and obesity, that can cause volume overload. These data suggest that extracardiac factors, via volume overload, may contribute to the pathophysiology of HFNEF in the elderly. 相似文献
992.
BACKGROUND AND AIMS: Increased plasma total homocysteine (Hcy) is a known cardiovascular disease (CVD) risk factor, related to several components of the established CVD risk profile. Observational studies support the role of modifying life-style related risk factors such as diet, physical activity and alcohol consumption in CVD prevention. Regular physical activity protects against coronary artery disease, possibly through its role in controlling risk factors such as hypertension, diabetes mellitus and obesity, but also independently. The aim of our study was to test the hypothesis that there is an association between physical activity, life-style habits and plasma Hcy levels in an elderly population. METHODS: In this cross-sectional study, 423 males and females aged 69.0 +/- 6.7 years completed an interview and laboratory examinations. Our main outcome measure was plasma levels of Hcy. RESULTS: Mean Hcy values were 10.5 +/- 5.5 micromol/L (11.4 +/- 6.1 for males and 9.3 +/- 4.5 for females; p < 0.001). Smoking and BMI were not found to be associated with Hcy levels. Physically active subjects, as well as B vitamin supplement users, had significantly lower Hcy levels (p = 0.002 and p = 0.004, respectively). In a multiple linear regression model, the Hcy level was 10% higher amongst participants with a sedentary life-style, 17% higher amongst males, 1% higher for each one-year increment in age, and 10% higher amongst participants who used no B vitamin supplements. CONCLUSIONS: Any level of physical activity was found to be an independent life-style habit associated with a lower Hcy level in an elderly population. This study supports existing recommendations for elderly persons to maintain a physically active life-style. 相似文献
993.
Early and late results of intracoronary arterial stenting after coronary angioplasty in dogs 总被引:4,自引:0,他引:4
G S Roubin K A Robinson S B King C Gianturco A J Black J E Brown R J Siegel J S Douglas 《Circulation》1987,76(4):891-897
Intimal dissection with acute closure represents the major complication associated with percutaneous transluminal coronary angioplasty (PTCA). Intracoronary stent devices offer the possibility of treatment for this sequela. We developed a balloon catheter-mounted, flexible coil stent for use in such cases. To determine the utility of this device and its immediate and long-term influence on arterial patency, 39 mongrel dogs had the stent placed after PTCA of the left circumflex or left anterior descending coronary arteries. Thirteen animals were treated before and after the procedure with warfarin. In this group there were three early deaths associated with stent thrombosis. Twenty-six animals were subsequently treated before and after with aspirin and dipyridamole. There were no early thrombotic events associated with stent placement in these animals. Late arteriographic examination revealed patent vessels in all dogs. Diameter stenosis for warfarin-treated dogs was 8 +/- 5% (mean +/- SD) at 2 months (n = 9), 6 +/- 4% at 6 months (n = 5), and 11 +/- 7% at 12 months (n = 3). Diameter stenosis for aspirin/dipyridamole-treated dogs was 9 +/- 3% at 2 months (n = 8), 8 +/- 5% at 6 months (n = 12), and 5% at 12 months (n = 1). Light and scanning electron microscopic analyses of stented arteries demonstrated incorporation of the stent wires into the arterial wall. Early findings included mild thrombosis localized to areas of wire entrenchment followed by rapid regrowth of endothelial and/or pseudoendothelial cells over trenches, exposed wires, and elastica.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
994.
995.
A D King S D Bell A W Stuttle M Carpani de Kaski A M Peters J P Lavender 《Chest》1992,101(6):1597-1600
BACKGROUND: Deep venous thrombosis (DVT) and pulmonary thromboembolic disease are difficult to diagnose, particularly following surgery. This report demonstrates the use of 111In-labelled platelet-specific monoclonal antibody, P256 Fab', for the diagnosis and study of the time course of thromboembolic disease in a patient following total hip replacement. METHOD: One hundred micrograms of pentetic acid (DTPA)-P256 Fab' was labelled with 8 to 10 MBq of 111In chloride by incubation at room temperature for 15 min. After dilution in physiologic saline, the tracer was injected intravenously on the third and sixth days postoperatively. Imaging of the chest, pelvis, and legs was carried out at 24, 48 and 72 h following each injection. RESULTS: The first image four days after surgery demonstrated activity in the right heart which moved to the right pulmonary artery on the following day. Activity was seen in both femoral veins; on the left, this increased over two days, followed by a reduction on the seventh day after surgery, at which time new activity was seen in the right heart. After a further two days, this activity moved to the left pulmonary artery. The DVT was confirmed by venography and the pulmonary embolism (PE) by ventilation perfusion scan. CONCLUSIONS: 111Indium-labelled platelet-specific monoclonal antibody, P256 Fab', provides a technique for studying the natural history of thromboembolic disease and its treatment. 相似文献
996.
Russell O Kosik Angela P Fan Yuanpeng Ren Baisheng Jiang Yunung Hsu Wenkai Li Xudong Zhao Qi Chen 《Lancet》2018
Background
Governmental policies in China have strengthened education in the medical humanities. Previous publications have highlighted the inadequacy of medical humanities education in China and have promoted their advancement and evaluation. Medical disputes and mistrust between doctors and patients in China have been ascribed to a paucity of proper medical humanities education at the medical student level. However, no studies to date have specifically examined the frequency, structure, and characteristics of the medical humanities curricula at all Chinese medical schools, making it difficult to draw a comprehensive understanding of its current state. We therefore aim to provide such an understanding of the current role of the medical humanities at Chinese medical schools.Methods
We did an exploratory cross-sectional study of medical humanities education in China. We did a comprehensive web-based search of records and curricula to identify all medical humanities courses at all tier-one western medicine Chinese medical schools. In China, only tier-one colleges can offer an education in clinical medicine. All medical schools' compulsory public curricula and the schools' medical humanities curricula were included in our analyses. The primary outcome was to categorise both quantitatively and qualitatively the role of the humanities at Chinese medical schools. We categorised all course data and analysed it using SPSS (version 20). Ethical approval was obtained by the Institutional Review Board of the National Yang-Ming University.Findings
Between July 1, 2017, and April 30, 2018, we identified 138 tier-one Chinese medical schools with compulsory public curricula, of which 93 (67%) had a medical humanities curricula. Eight medical humanities course types were identified. On average, each school offers 3·84 types of different medical humanities courses. The types of courses that are offered the most are medical psychology or clinical psychology (72 [77%] of 94), medical ethics (68 [72%]), hygienic or medical jurisprudence (56 [60%]), and doctor–patient communication (46 [49%]). Medical humanities courses account for 3–10% of the total credits medical students are required to obtain to graduate in China. The compulsory Ideological and Political Theory curriculum accounts for 6–8% of credits required to graduate. This curriculum includes Mao Zedong Thought, Modern Chinese History, Marxism, Socialism with Chinese Characteristics, and Moral Education and Law, and is required of all students, not solely medical students.Interpretation
Medical humanities courses at western medical schools such as the University of Oxford and Harvard Medical School account for 15% and 25% of the total credits required to graduate, respectively. In China, medical humanities education accounts for a substantially smaller portion of the curriculum. Despite ongoing medical disputes and doctor–patient tension, only half of medical schools offer doctor–patient communication type courses. However, China's Ideological and Political Theory curriculum also has a humanistic intent, and when added with medical humanities courses, the two together account for 9–18% of the total credits required to graduate. These unique curricular components serve to support governmental priorities, including developing leaders who follow the so-called rule of law and the rule of virtue. These traits of China's medical humanities curricula match China's national political ideology. However, a more coherent longitudinal medical humanities framework specifically aimed at strengthening the patient–doctor relationship would be useful. China's endeavours to foster medical humanities education reform should be actively promoted at the research, policy, and practice level.Funding
The Republic of China Ministry of Science and Technology (grant MOST 105-2511-S-010 -002 -MY2). 相似文献997.
Cardiac fibroblasts in culture produce factor(s) that induce hypertrophy of neonatal rat ventricular myocytes in vitro. As
in vivo, the myocyte hypertrophy response in culture is characterized by an increase in cell size and contractile protein
content, and by the activation of embryonic genes, including the gene for atrial natriuretic peptide. The purpose of this
study was to identify the factor(s) produced by fibroblasts that induce myocyte hypertrophy. The fibroblast hypertrophy activity
was inhibited using a combination of the endothelin A receptor blocker BQ-123 and an antibody to leukemia inhibitory factor.
The individual antagonists each caused a partial inhibition. The mRNAs for both leukemia inhibitory factor and endothelin
were detected by RT-PCR analysis and the concentration of both proteins was determined to be approximately 200 pmol/L in the
conditioned medium using immunoassays. Purified leukemia inhibitory factor and endothelin each induced distinctive morphological
changes in the myocytes. Their combination generated a different morphology similar to that induced by fibroblast conditioned
medium. Each factor also induced atrial natriuretic peptide production, but both were required for the myocytes to produce
the levels measured after exposure to fibroblast conditioned medium. These results show that hypertrophy activity produced
by cardiac fibroblasts in culture is a result of leukemia inhibitory factor and endothelin. 相似文献
998.
We report the first case of sino-orbital mucormycosis caused by Rhizopus rhizopodiformis. Therapy consisted of conservative surgical drainage and intravenous amphotericin B. The patient, an insulin-dependent diabetic, survived her infection with minimal residual deformity. This case and a literature review suggest that infection due to R. rhizopodiformis in diabetics might be more amenable to treatment than mucormycosis caused by other species of fungi. Speciation of such fungi would permit the determination of species specific mortality rates, and may be of therapeutic and prognostic value. 相似文献
999.
S. A. Pilkington R. Bhome R. E. Welch F. Ku C. Warden S. Harris J. Hicks C. Richardson T. C. Dudding J. S. Knight A. T. King A. H. Mirnezami N. E. Beck P. H. Nichols K. P. Nugent 《Techniques in coloproctology》2018,22(7):545-551
Background
Botulinum toxin injected into the internal anal sphincter is used in the treatment of chronic anal fissure but there is no standardised technique for its administration. This randomised single centre trial compares bilateral (either side of fissure) to unilateral injection.Methods
Participants were randomised to receive bilateral (50?+?50 units) or unilateral (100 units) Dysport® injections into the internal anal sphincter in an outpatient setting. Injection-related pain assessed by visual analogue scale was the primary outcome measure. Secondary outcomes were healing rate, fissure pain, incontinence, and global health scores.Results
Between October 2008 and April 2012, 100 patients with chronic anal fissure were randomised to receive bilateral or unilateral injections. Injection-related pain was comparable in both groups. There was no difference in healing rate. Initially, there was greater improvement in fissure pain in the bilateral group but at 1 year the unilateral group showed greater improvement. Cleveland Clinic Incontinence score was lower in the unilateral group in the early post-treatment period and global health assessment (EuroQol EQ-VAS) was higher in the unilateral group at 1 year.Conclusions
Injection-related pain was similar in bilateral and unilateral injection groups. Unilateral injection was as effective as bilateral injections in healing and improving fissure pain without any deterioration in continence.1000.
Kuo CH Hu HM Tsai PY Yang SF Chang LL Wang JY Chen A Jan CM Wang WM Wu DC 《Journal of gastroenterology》2008,43(1):32-37
Background. Our aim was to evaluate the accuracy of the stool antigen test and the optimal time point for detecting Helicobacter pylori infection in a Mongolian gerbil model. Methods. We inoculated 8-week-old Mongolian gerbils with H. pylori (Vac A (+)/CagA(+)). The gerbil-infected model was developed as follows: H. pylori was put into broth (about 109 CFU/ml), and 50 gerbils were then fed with 1 ml intragastrically twice within a 3-day interval. Another ten gerbils were
fed broth only. Twenty-six weeks after the inoculation, the gerbils were killed. The gastric mucosa was sampled for a series
of examinations including culture, histology, rapid urease test, and polymerase chain reaction. Stool samples for a stool
antigen test, H. pylori-specific stool antigen assay (HpSA), were collected during weeks 4, 6, 8, 12, and 26 after inoculation. Of the 50 gerbils
inoculated with H. pylori, the inoculation was successful in 88%. Severe active gastritis, ulceration, and intestinal metaplasia were obvious. Results. The HpSA test results were sensitivity, 88.6%; specificity, 100%; positive predictive value (PPV), 100%; negative predictive
value (NPV), 54.5%, and accuracy, 90%. The HpSA test began to be more sensitive and accurate (P < 0.05) beginning during week 6 after inoculation. We also found that H. pylori could be detected earlier and more easily in the group with high H. pylori density. Conclusions. HpSA seems to be suitable for confirming colonization of gerbils with H. pylori. The optimal testing time point is around 6 weeks after inoculation. This test is a good choice for long-term observation
of H. pylori infection in Mongolian gerbils. 相似文献