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1.
1. Parathyroid hypertensive factor (PHF) has been implicated in the pathogenesis of several forms of hypertension. We aimed to establish a PHF bioassay using spontaneously hypertensive rat (SHR) plasma. 2. Spontaneously hypertensive rats were confirmed hypertensive and their plasma was dialysed and injected into anaesthetized normotensive rats. 3. Haemodynamic responses to injected SHR plasma were uninterpretable during pentobarbital anaesthesia due to blood pressure (BP) fluctuation. Under halothane anaesthesia, BP was stable but did not rise following SHR plasma injection. Using filtered, undialysed plasma and a different brand of pentobarbital, no consistent BP response was observed following SHR plasma injection. 4. We were unable to detect PHF in the SHR.  相似文献   

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Left ventricular wall motion was assessed in 105 consecutive patients both invasively, using biplane cineangiography, and noninvasively, by a real-time, phased-array, two-dimensional echocardiography system. Ventricular wall motion in five anatomic areas of the ventricle (anterolateral, posterolateral, apical, septal, and inferior) was analyzed by both methods in a double-blind manner. Two-dimensional echocardiographic images were deemed adequate for analysis in 82% of the regions (430 of 525). Fifty-five discrepancies were noted in the comparison of the remaining 430 regions. The reasons for discrepancies in interpretation between the two methods were established for 54 during retrospective review: 33 were due to echocardiography (inadequate target visualization, observer error, or tangential echo views). Fifteen were related to angiography (overlay of silhouettes or observer error), and six were due to other reasons including definition problems or spatial orientation difficulties. Both real-time, two-dimensional echocardiography and cineangiography have advantages and disadvantages. The techniques used together could provide more complete information concerning ventricular wall movement than is now currently available.  相似文献   

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Mono- and B-mode echocardiography is inferior to clinical evaluation and haemodynamic studies for timing of cardiac transplantation in idiopathic and/or ischemic cardiopathy. Some echo- and Doppler-derived variables are of prognostic significance as predictive guides in patients assessed for cardiac transplantation.  相似文献   

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Stress echocardiography is nowadays an integral part of the diagnosis of ischaemic heart disease. In the submitted review the authors draw attention to the fact that ischaemic heart disease is no longer the domain of stress echocardiography. In recent years the interest of cardiologists in this method increased also in other cardiac diseases. Based on the appropriate pathophysiological mechanism of cardiac affection stress echocardiography is used to test left ventricular function after a dynamic or pharmacological stress, i.e. increased cardiac activity and cardiac minute volume in a number of heart diseases where we must know the extent of left ventricular affection and the functional reserve of the myocardium. These tests were also introduced to evaluate the impact of valvular disease and function of artificial grafts to evaluate left ventricular function in the transplanted heart. Stress echocardiograph holds its place also in paediatrics.  相似文献   

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1. Noradrenergic (NA) nerve fibre distribution was investigated in the epicardium and myocardium of the heart in stroke-prone spontaneously hypertensive rats (SHRSP) and was compared to that in normotensive Wistar-Kyoto (WKY) rats. Fluorescent NA nerve fibres in the left and right epicardium of both strains aged 10, 30, 60, 90 and 180 days, and in the myocardium of left and right ventricles and the ventricular septum of both strains aged 30, 90 and 180 days were examined by the glyoxylic acid method. The distribution densities of NA nerve fibres were measured by quantitative image analysis. 2. The distribution pattern of NA nerve fibres in the epicardium of both strains showed a constant meshwork pattern throughout the entire examination period. 3. In the myocardium, NA nerve fibres were distributed irregularly between myocytes of both strains in all ages examined. 4. The densities of NA nerve fibres in the epicardium of SHRSP were significantly higher (P < 0.01 and 0.05; Student's t-test, 6 d.f.) than those of WKY at all ages examined except left epicardium at 90 days of age. 5. The densities in the right myocardium in 30 and 90 day old SHRSP were significantly higher (P < 0.05; Student's t-test, 6 d.f.) than those of WKY. 6. NA hyperinnervation in the epicardium and the myocardium of SHRSP may be assumed to be caused by the hyperfunction of the stellate ganglia which innervate the heart and may give rise to hypertrophy of the heart in SHRSP by a trophic effect of NA nerve fibre.  相似文献   

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BACKGROUND: Inhibition of apoptosis, or programmed cell death, may be critical both in the development of cancer and in determining response to therapy. The authors examined the expression of two related apoptotic inhibitors, Bcl-2 and Bcl-xL, in pretreatment biopsies from a series of 42 patients with squamous cell carcinoma of the head and neck. The observed pattern of apoptotic inhibitor expression was compared with that of the p53 gene product, another factor implicated in carcinogenesis and therapeutic responsiveness. METHODS: Formalin fixed, paraffin embedded tumor biopsies from 42 patients with locally advanced squamous cell carcinoma of the head and neck were analyzed by immunohistochemistry using antibodies specific for Bcl-xL, Bcl-2, and p53. Measures of clinical outcome, including disease specific survival and overall survival, were compared among the groups. RESULTS: The majority of the tumors demonstrated enhanced expression of either Bcl-2 or Bcl-xL compared with surrounding normal epithelium. Fifty-two percent of the tumors had up-regulated Bcl-xL, and 17% had up-regulated Bcl-2. There was no overlap between these groups. Expression of Bcl-2, but not Bcl-xL, was correlated with improved disease specific survival. Immunohistochemically detectable p53 expression (48% of tumors) was not found to correlate with expression of either Bcl-xL or Bcl-2 and, in this series, was not a predictor of clinical outcome. CONCLUSIONS: These results suggest that disruption of apoptotic control pathways is an important event in the evolution of squamous cell carcinoma of the head and neck. A common mechanism for this disruption involves overexpression of Bcl-xL, Patients whose tumors demonstrate Bcl-2 positivity, even with locoregionally advanced disease, appear to have a high likelihood of cure with aggressive combined modality therapy and may be treated successfully with less toxic therapy.  相似文献   

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In the present study the prevalence of obesity and its association with ischemic heart disease, recognized according to clinical criteria (chest pain or previous infarction) and/or instrumental data, were described in 8,847 normotensive subjects and in 867 hypertensive subjects, hospitalized during a ten years period (1983-1992), through a cross-sectional study. In view of this all the subjects were considered as lean or obese according to their body mass index (BMI) and to sex specific cut-off values reported in the Italian Consensus Conference on Obesity. In particular, according to BMI values, the subjects were grouped as lean, overweight, moderate and severe obese subjects. Our results indicated that 3,982 normotensive subjects (45%) could be considered lean, whereas 2,654 of them (30%) were overweight, 1,769 of them (20%) were moderate obese and 442 of them (5%) were severe obese. On the contrary only 206 hypertensives (23.7%) might be considered lean, whereas 313 (36.1%) were overweight, 302 (34.8%) were moderate obese and 46 (5.3%) were severe obese. According to age subgrouping (lower than or equal to 65 years or higher than 65 years) the distribution of hypertensives within the lean, overweight, moderate and severe obese groups did not change significantly, but, according to sex subgrouping, the distribution of hypertensives within the BMI groups was significantly different (chi 2, p < 0.001). When we considered the degree of hypertension, distribution of hypertensives was significantly different according to c2 test (p < 0.004), suggesting that the percentage of the subjects with severe hypertension increased only in subjects with severe obesity. Concomitant ischaemic heart disease (IHD) was also documented in 350 normotensives (4%) and in 119 hypertensives (13.8%). The prevalence of IHD was not significantly different in lean, overweight, moderate and severe obese hypertensives, also when sex and smoking habits were considered. Our data indicated a strong association between obesity and hypertension. In addition they may be consistent with the suggestion that obese hypertensives were not characterized by a lower risk of ischaemic heart disease (IHD), than lean hypertensives.  相似文献   

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Stress echocardiography has evolved as a routinely employed non-invasive method for the evaluation of patients with coronary artery disease. The diagnostic accuracy of stress echocardiography for the detection of myocardial ischemia is comparable to scintigraphic myocardial perfusion imaging, and may even have a higher specificity for the evaluation of myocardial viability. User-friendliness including patient and investigator safety, availability and mobility of the method, and environmental compatibility, is superior to that of scintigraphy. The potential for future developments, especially in the field of digital imaging and telecommunication, is great. Last but not least, echocardiography is the method most familiar to cardiologists. The sum of these arguments renders stress echocardiography the superior method to scintigraphy in the evaluation of patients with coronary artery disease.  相似文献   

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The diagnostic efficacy of M-Mode and 2-d echocardiography for the detection of malfunctioning prosthetic valves was studied in twenty-nine patients with prosthetic valves and clinical deterioration. Echocaradiographic abnormalities were found in 8 of 12 patients with confirmed valve dysfunction; 30.8% of the cases had false negative echo tracings. In 17 patients with normal echocardiographic pictures of the valves another cause of clinical deterioration was found (congestive heart failure, pericardial effusion, aneurysm of aortic root). In this study M-Mode and 2-d echocardiography had an excellent diagnostic accuracy rate in distinguishing congestive heart failure from valve dysfunction. Comparing the data of M-Mode and 2-d registration, both methods are found to be complementary. A major advantage of the 2-d echocardiography is its enhanced spatial orientation, whereas M-Mode echocardiography enables better evaluation of valve movements and corresponding time intervals and recognition of quick movements and fibrillations.  相似文献   

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BACKGROUND: The increasing number of transgenic and targeted mutant mice with embryonic cardiac defects has resulted in the need for noninvasive techniques to examine cardiac structure and function in early mouse embryos. We report the first use of a novel 40-MHz ultrasound imaging system in the study of mouse cardiac development in utero. METHODS AND RESULTS: Transabdominal scans of mouse embryos staged between 8.5 and 13.5 days of gestation (E8.5 to E13.5) were obtained in anesthetized mice. Atrial and ventricular contractions could be discerned from E9.5, and changes in cardiac morphology were observed from E9.5 to E13.5. Hyperechoic streaming patterns delineated flow through the umbilical, vitelline, and other major blood vessels. Diastolic and systolic ventricular areas were determined by planimetry of the epicardial borders, and fractional area change was measured as an index of contractile function. Significant increases in ventricular size were documented at each stage between E10.5 and E13.5, and the ability to perform serial imaging studies over 3 days of embryonic development is described. Finally, the detection of vascular cell adhesion molecule 1 (VCAM-1) homozygous null mutant embryos demonstrates the first example of noninvasive, in utero analysis of cardiac structure and function in a targeted mouse mutant. CONCLUSIONS: We used 40-MHz echocardiography to identify key elements of the early mouse embryonic cardiovascular system and for noninvasive dimensional analysis of developing cardiac ventricles. The ability to perform serial measurements and to detect mutant embryos with cardiac defects highlights the usefulness of the technique for investigating normal and abnormal cardiovascular development.  相似文献   

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Black hypertensive persons have been observed to have a greater degree of left ventricular hypertrophy than white hypertensives. However, previous studies have matched groups for blood pressure (BP) measured in the clinic, and it has been demonstrated that black hypertensives have an attenuated nocturnal BP dip. Clinic BPs may thus underestimate mean 24-hour BP in this group. To investigate whether the differences in left ventricular hypertrophy can be accounted for by the greater mean 24-hour BP in black hypertensives, 92 previously untreated hypertensives were studied with 24-hour ambulatory BP monitoring and echocardiography. The 46 black hypertensives (24 men and 22 women) were matched with the 46 white hypertensives for age, gender, and mean 24-hour BP. Despite similar mean 24-hour BPs (blacks, 142/93 mm Hg; whites, 145/92 mm Hg; P=.53/.66), the black group had a smaller mean nocturnal dip than the white group (blacks, 8/8 mm Hg; whites, 16/13 mm Hg; P<.01). In addition, mean left ventricular mass index (LVMI) was greater (blacks, 130 g/m2; whites, 107 g/m2; P<.001). Mean 24-hour systolic BP was significantly related to LVMI in both groups (blacks, r=.45, P<.01; whites, r=.56, P<.01). However, systolic BP dip correlated inversely with LVMI only in the black group (blacks, r=-.30, P<.04; whites, r=.05, P=.76). In a multiple regression model, LVMI was independently related to both mean daytime BP and mean nocturnal BP dip in black subjects but only to mean daytime BP in white subjects. In conclusion, the increased left ventricular hypertrophy observed in black hypertensives compared with white hypertensives is not accounted for by differences in mean 24-hour BP. However, LVMI in black hypertensives appears to be more dependent on nocturnal BP than that in white hypertensives; this, coupled with the attenuated BP dip in black hypertensives, suggests that the BP profile rather than 24-hour BP may be important in determining the differences in left ventricular hypertrophy.  相似文献   

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BACKGROUND: The noninvasive prognostic assessment of coronary artery disease (CAD) in hypertensive patients represents an unresolved task to date. In this study, we investigated the value of dipyridamole stress echocardiography in risk stratification of hypertensive patients with chest pain and unknown CAD. METHODS AND RESULTS: Dipyridamole stress echocardiography was performed in 257 hypertensives (110 men; age, 63+/-9 years) complaining of chest pain and without a history of CAD. No major complications occurred. Four tests were interrupted prematurely because of side effects, with 98. 4% feasibility of test. A positive echocardiographic response was found in 72 patients (27 during the low-dose [0.56 mg/kg]). During the follow-up (32+/-18 months), 27 cardiac events occurred: 3 deaths, 8 infarctions, and 16 cases of unstable angina. Moreover, 27 patients underwent coronary revascularization. At multivariate analysis, the positive echocardiographic result (OR, 5.5; 95% CI, 1.4 to 16.6) was the only predictor of hard cardiac events (death, infarction). Considering spontaneous cardiac events (death, infarction, and unstable angina) as end points, the positive echocardiographic result (OR, 4.2; 95% CI, 1.8 to 9.6) and family history of CAD (OR, 4.2; 95% CI, 1.5 to 6. 9) were independently associated with prognosis. The 3-year survival rates for the negative and the positive populations were, respectively, 97% and 87% (P=0.0019) considering hard cardiac events and 96% and 74% (P=0.0000) considering spontaneous cardiac events. CONCLUSIONS: Dipyridamole stress echocardiography is safe, highly feasible, and effective in risk stratification of hypertensives with chest pain and unknown CAD. At present, it represents an attractive option for prognostic assessment of this clinically defined population.  相似文献   

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Two competing hypotheses explaining gender bias in cardiac care were tested. The first posits that women's coronary heart disease (CHD) symptoms are simply misinterpreted or discounted. The second posits that women's CHD symptoms are misinterpreted when presented in the context of stress. In two studies, medical students and residents randomized to 2 (male vs. female) × 2 (stress vs. nostress) experiments read vignettes of patients with CHD symptoms and indicated their diagnosis, treatment, and symptom origin interpretation. Both studies disconfirmed the first hypothesis and strongly supported the second. Only when stress was added did women receive significantly lower CHD diagnoses and cardiologist referrals than men and did the origin interpretation of women's CHD symptoms (e.g., chest pain) shift from organic to psychogenic. Neither participants' gender nor their attitude toward women influenced assessments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The diagnosis of vestibulocochlear nerve and statoacoustic organ lesions is based on the symptoms vertigo, hearing loss and tinnitus. The most common diseases are vestibular neuronitis, Ménière's disease, benign positional vertigo and sudden hearing loss. 6 patients are presented, complaining of at least one of the symptoms vertigo, hearing loss or tinnitus. They were suspected of suffering from a peripheral audiovestibular disease when admitted to the clinic, but all of them revealed other pathologies. A careful history and step-wise otoneurologic diagnostics including clinical examination, otoneurologic testing, audiologic tests, electronystagmography, acoustic evoked potentials and imaging techniques finally resulted in the correct diagnosis.  相似文献   

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