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151.
《Substance use & misuse》2013,48(12-13):1751-1784
Using data for an ongoing study of fatalities associated with cocaine use in Dade County Florida, USA, temporal trends are described and risk factors are examined for fatal overdose with case-control analysis for the years 1978-1985. While the number of deaths from accidental cocaine toxicity (ACTDs) rose consistently, median annual concentrations of cocaine in autopsy blood did not. When 125 ACTDs were compared with a control group, the following risk factors were identified: fresh injection sites, arteriosclerosis, and ventricular hypertrophy. 相似文献
152.
《Substance use & misuse》2013,48(9):1132-1137
This review evaluates the documented cardiovascular functioning among anabolic-androgenic steroid (AAS) users. AAS users manifest a reduction in HDL cholesterol, increased inflammatory markers, and oxidative stress. Strong evidence associating AAS use with blood pressure at hypertensive levels, as well as hypertrophy and cardiac dysfunction has also been reported. Both epidemiological and autopsy studies attest the relationship between AAS use and early mortality. The review's limitations are noted. 相似文献
153.
Anatomical abnormalities such as unusual bifurcations or aberrant arteries of the radial artery are extremely rare and due to malformation or disruption of the vascular net. We present a case of a 64 year old woman with a high bifurcated dorsal branch of the left radial artery, consulting us for a pulsatile mass in the anatomical snuffbox after a fall. The mass measured 3–4 mm in diameter and was located on the dorsal aspect of the wrist over the anatomical snuffbox. Primary imaging studies using Duplex Ultrasound suggested an aneurysm of the radial artery, further imaging with arteriogram revealed a high bifurcation of the dorsal branch of the radial artery, presenting with an aneurysm. The deep palmar branch of the ulnar artery was the dominating vessel, allowing ligation and excision of the aneurysm. Histological evaluation revealed intimal wall hyperplasia within the aneurysm, suggesting an injury as initiating factor. A review of the literature showed that this abnormality of high bifurcation of the dorsal palmar branch of the radial artery has not been previously reported. Management of aneurysms at the wrist is discussed. 相似文献
154.
Histological studies of the effects of oral administration of extract of Aspilia africana, used in ethno medical practice in Africa for the management of various ailments, on the ovarian tissues of matured female Wistar rats were studied. The rats (n=24), average weight 182g were randomly assigned into two treatment (n=16) and a control (n=8) group. The rats in the treatment groups received 0.5g/kg and 1g/kg of aqueous extract of Aspilia africana orally through orogastric tube for fourteen days, while the control rats received equal volume of distilled water without the extract of Aspilia added. The rats were fed with growers'' mash and were given water liberally. The rats were sacrificed on day fifteen of the experiment. The ovary was carefully dissected out and quickly fixed in 10% formal saline for routine histological study after H&E method. The histological findings indicated that the treated sections of the ovary showed cellular hypertrophy of the theca folliculi, distortion of the basement membrane, degenerative and atrophic changes in the oocyte and zona granulosa. There were marked vacuolations appearing in the stroma cells. These findings indicate that Aspilia africana consumption may probably have adverse effects on the ovaries by its deleterious effects on the oocytes and stroma cells of ovary of adult Wistar rats. It is recommended that further studies aimed at corroborating these observations be conducted. 相似文献
155.
Summary The aim of the study was to investigate the effect of propranolol upon the activity of proteases in rat myocardium subjected to aortic stenosis.In acute heart hypertrophy induced by aortic stenosis, the activity of all three proteases in the myocardium does not change significantly. Propranolol in the concentration of 10–6 to 2×10–4 M inhibited proteolytic activity dependent on neutral proteases.The degree of inhibition increased simultaneously with increasing concentrations of propranolol.Propranolol in a low concentration (10–6–10–5 M) also inhibited proteolytic activity dependent on alkalinc and acidic proteases, but in higher concentration (10–4–2×10–4 M) stimulated proteolytic activity of these enzymes 2–3 times. 相似文献
156.
157.
Kasikcioglu E Oflaz H Akhan H Kayserilioglu A Mercanoglu F Umman B Bugra Z 《Heart and vessels》2004,19(4):183-188
The aim of this study was to determine left ventricular (LV) morphology and aortic function in power athletes and to compare them with normal subjects. Thirty-two elite male wrestlers and 15 age-matched healthy male controls were included. All subjects underwent echocardiographic examination. Measurements included LV cavity dimension at systole and diastole, wall thickness, diastolic parameters, and aortic diameter, 3cm above aortic valve, at systole and diastole. Left ventricular mass and mass index were found to be higher in the athletes than in control subjects. The aortic distensibility index was found to be reduced in the athletes compared with controls (2.53 ± 0.91 vs 3.94 ± 1.77cm2dyne–1 10–6, P = 0.003), while the aortic stiffness index was significantly higher in the athletes than in controls (9.12 ± 3.23 vs 6.65 ± 2.35, P = 0.02). However, LV end-systolic wall stress was lower in the athletes than in controls. Furthermore, transmitral early (E) and late (A) peak velocity, peak velocity of the myocardial systolic wave (S
m), and early (E
m) and atrial (A
m) diastolic waves at the inferior wall were higher in the athletes than in controls. Reduced aortic distensibility in elite power athletes may be one of the cardiovascular adaptation factors which affect LV hypertrophy. 相似文献
158.
Findings of 185 patients and 271 control subjects are presented for the assessment of work capacity in hypertensive individuals (primary hypertension); an attempt at classification by hypertensive stage is seen as an essential presupposition. The subdivision into three stages recommended by the Experts' Commission of the WHO places the effects of hypertension on the organism, especially on the heart, in the focal point. This appears justified from a prognostic, pathophysiological, and therapeutic point of view. Hemodynamics in the examined patients undergo increasing impairment in relation to the stage of hypertension with a decrease in maximum cardiac index and work capacity and an increase in myocardial oxygen requirement. Initially, only the diastolic cardiac function is impaired; however, in advanced stages, the systolic function of the heart is impaired as well. Evaluation of work capacity is usually possible from a cardiac point of view by means of noninvasive echocardiographic and spiroergometric methods. The mass/volume ratio of the left cardiac ventricle and the relationship between left ventricular muscle mass (or volume) and work capacity are especially important. Both experience characteristic changes depending on the stage of hypertension and thus permit precise determination of work capacity, progress controls, and delineation from physiological cardiac hypertrophy (athletic heart). 相似文献
159.
Dr. James B. Meigs MD MPH Michael J. Barry MD Joseph E. Oesterling MD Steven J. Jacobsen MD PhD 《Journal of general internal medicine》1996,11(9):505-512
OBJECTIVE: Calculation of likelihood ratios for serum prostate-specific antigen (PSA) levels to discriminate potentially-curable prostate
cancer in men selected for having benign prostatic hyperplasia (BPH) or in randomly selected men.
DESIGN: Retrospective analysis of prospectively measured PSA levels.
SETTING: A tertiary referral center, a multicenter randomized controlled trial, and a community-based study, all providing PSA data.
PATIENTS: We used PSA measurements from four groups of men aged 50 to 79 years: 276 men with organ-confined prostate cancer treated
with radical prostatectomy, 305 randomly selected men without clinical evidence of prostate cancer or a history of surgery
for BPH recruited for a community study, 173 men without cancer but with BPH coming to prostatectomy, and 770 men without
cancer and with symptoms of BPH enrolled in the North American finasteride clinical trial.
MEASUREMENTS AND MAIN RESULTS: Age-standardized, stratum-specific likelihood ratios for organ-confined prostate cancer were calculated separately for unselected
men in the community sample and for selected men with BPH (pooling both BPH populations). Likelihood ratios ranged from 0.2
for PSA between 0.0 and 2.0 ng/mL to 54.8 for a PSA level of 10.1 ng/mL or higher in unselected men, but rose to only 2.9
for PSA values of 10.1 ng/mL or higher in men with BPH. Forty percent of the men in the community study had moderate to severe
lower urinary tract symptoms. In these men, likelihood ratios ranged from 0.2 for PSA values between 0.0 and 2.0 ng/mL to
17.2 for PSA values of 6.1 ng/mL or higher, while in men with no or mild symptoms, likelihood ratios rose to 26.9 for PSA
values of 6.1 ng/mL or higher.
CONCLUSIONS: Likelihood ratios for PSA test results allow stratification of men along a continuum of risk for prostate cancer. Likelihood
ratios demonstrate that the ability of the PSA test to discriminate potentially curable prostate cancer from BPH is dramatically
lower in men selected with lower urinary tract symptoms than in randomly selected men.
Presented in abstract form at the 18th annual meeting of the Society of General Internal Medicine, San Diego, Calif, May 6,
1995, and subsequently published in J Gen Intern Med. 1995;4(suppl W):73.
Supported by a Patient Outcomes Research Team (PORT-II) grant from the Agency for Health Care Policy and Research (HS 08397)
and by a grant from the U.S. Public Health Service, National Institutes of Health (AR 30582). 相似文献
160.
Franz H. Messerli Federico Soria 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1994,8(Z3):557-563
Left ventricular hypertrophy has been documented to be a powerful risk factor for sudden death, acute myocardial infarction, and other cardiovascular morbidity and mortality. The major determinant of left ventricular mass is the hemodynamic burden. However, the hypertrophic process is modified by demographic parameters (age, sex, race), nutritional parameters (salt intake, alcohol, obesity), and neuroendocrine factors (angiotensin, catecholamines, growth hormones, etc.). Ventricular ectopy and more serious arrhythmias are commonly seen in patients with left ventricular hypertrophy. Specific antihypertensive therapy will reduce left ventricular hypertrophy, although not all antihypertensive drugs are equipotent in this regard. A reduction in left ventricular hypertrophy has been shown to diminish left-ventricular-hypertrophy-associated arrhythmias. However, it remains to be shown that patients with left ventricular hypertrophy and ventricular ectopy are at a higher risk of sudden death than those without ventricular ectopy and that the reduction of left-ventricular-hypertrophy-associated ventricular ectopy indeed confers a clinical benefit that exceeds the one from the reduction in arterial pressure alone.Modified with permission. Messerli FH and Soria F: Left ventricular hypertrophy and ventricular ectopy. In Podrid PJ and Kower PR, eds.Arrhythmia: A Clinical Approach. ¢ Williams & Wilkins, 1994. 相似文献