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Direct measurement of intra-arterial blood pressure (BP) for 24-h provides approximately 100,000 values that vary enormously, but each (BPi) can be expressed by the equation BPi = BP0 + DeltaBPi (BP0, base BP; DeltaBPi, BP increment, i=1, 2, ..., 100 x 10(3)). About 20% of outpatients with hypertension exhibit white-coat hypertension (WCH). In such patients, DeltaBPc (i = c; c, time at the clinic) is surmised to be large. A method for explaining the physiological factors in DeltaBPc and the estimation of base BP in the outpatient clinic is important. This study addresses this issue. A total of 293 subjects were divided into four groups: 1) WCH group, 45 individuals (office BP > or = 140/90 mmHg and 24-h indirect BP < 125/80 mmHg); 2) normotensive (NT) group, 84 controls matched for age and sex; 3) WHO-I group, 95 hypertensive patients with WHO stage I (office BP > or = 140/90 mmHg and 24-h BP > or = 125/80 mmHg); and 4) WHO-II group, 69 hypertensive patients with WHO stage II. Their BPc and heart rate (HR; HRc, clinic HR) values were measured by a BP-ECG monitoring device in the outpatient clinic. Power-spectral analysis was used to obtain the ratio between the low-frequency component (LF) and high-frequency component (HF) of ECG-RR variability (LF/HF = LH). Twenty-four-hour indirect BP (and BP0) and base HR (HR0) were measured by a portable device (TM2425) at 30-min intervals. Then, DeltaBPc (= BPc - BP0) was estimated by performing linear multivariate analysis applying the model equation DeltaBPc = (BPc -alphaLH)(1-betaHR0/HRc) + epsilon to the above variables (alpha and beta, constant values; epsilon, error). This model equation made it possible to estimate BP0 (and DeltaBPc) with a high coefficient of correlation (r > or = 0.85, mean of error less than 0.82 +/- 5.9 mmHg). The predictive accuracy for discrimination between WCH and sustained hypertension (WHO-I and WHO-II groups) by this equation was 88%. The new DeltaBP-estimation device (BP-ECG monitor) enabled us to infer BP0 and is therefore useful in estimating WCH in the outpatient clinic.  相似文献   
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We report herein, a new method devised of producing neurogenic stress ulceration in rats. An experimental subarachnoid hemorrhage (SAH) was produced in rats by injecting 0.2 ml of arterial blood from other rats into the cisterna magna. Three days later, the rats were laparotomized for 1 hour under ether anesthesia, followed by restraint for 3 hours in wakefulness. The SAH rats were found to develop stress ulcers (UL-I) in the glandular stomach, which were significantly (p less than 0.001) more marked than those in non-SAH rats. Measurements were performed on gastric acid secretion, an important aggressive factor. It was found that the SAH rats undergoing the laparotomy-restraint stress showed a more marked increase in gastric acid secretion and a more marked reduction in MBF, than the non-SAH rats. The effects of bilateral vagotomy, upper abdominal sympathectomy and bilateral adrenalectomy were examined, and it was revealed that the SAH rats were under the condition of hyperreactivity both in the sympathetic and parasympathetic systems and, on this basis, the laparotomy-restraint stress caused the stress gastric ulceration. In this rat model, the laparotomy stress was applied under anesthesia and any exposure to low temperatures which may have interfered with blood circulation was avoided.  相似文献   
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OBJECTIVE: To investigate the correlation between scalp-recorded electroencephalographic (EEG) and electrocorticographic (ECoG) activities during ictal periods. METHODS: Simultaneous EEG and ECoG recordings with chronic subdural electrodes were performed in eight patients with partial epilepsy. RESULTS: In two cases where the ictal ECoG discharges originated in deep brain structures such as the hippocampus and interhemispheric surface of the frontal lobe, ictal discharges could not be detected on EEG until they expanded to the cortex of convexity. In four cases, the ictal onset zones were located in the lateral convexity. When synchronous or near synchronous ictal ECoG discharges with amplitudes of 200-2000muV were recorded on more than 8-15cm(2) of cortex, corresponding discharges were recorded on EEG in these four cases. However, in a case of frontal lobe epilepsy, asynchronous ictal ECoG discharges were recorded on 10 electrodes of convexity but no ictal EEG activity was recorded. Furthermore, in two frontal lobe epilepsy cases, ictal EEG discharges did not always reflect the ictal ECoG spike, but occasionally reflected slow background ECoG activity around the ictal discharges. CONCLUSIONS: Multiple factors such as the width of the cortical area involved, amplitude of ictal discharges and degree of synchronization of electrical potentials play important roles in the appearance of ictal EEG recordings, and the relationship between ictal EEG and ECoG is not straightforward.  相似文献   
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Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  相似文献   
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The aim of this study was to clarify and compare the temporal course of bone mineral density (BMD) between fast bone losers and normal residents in Miyama Village, a rural Japanese community. BMD was measured over a 10-year period in a cohort study in Miyama Village, Wakayama Prefecture, Japan, to provide information on rate of bone loss in the mature and elderly population. Subjects (n=400) were selected by sex and age stratum from the full list of residents born in 1910–1949, with 50 men and 50 women in each age decade. Baseline BMD of the lumbar spine and proximal femur was measured using dual energy X-ray absorptiometry in 1990, 1993, 1997 and 2000. In the cohort, 171 men and 189 women completed the follow-up survey performed in 1993. After calculating the rate of bone loss between 1990 and 1993, the greatest tertile from the distribution of bone loss was categorized as fast bone losers, with the remainder considered as normal subjects. Changes in BMD were compared between normal subjects and fast bone losers over the 10-year period. Mean rate of change for BMD at both lumbar spine and femoral neck in fast bone losers recovered to levels similar to those in normal subjects over 7 years of observation. By contrast, BMD at the lumbar spine and femoral neck decreased steeply over the 10-year period in both groups, and mean BMD for fast bone losers was significantly lower than that of normal subjects (P<0.05). These differences were apparent only at the lumbar spine in both men and women, even after adjusting for age. These results indicate that fast bone loss is a transient phenomenon rather than a fixed status, although individuals who have been categorized as fast bone losers at some stage continue to display low BMD in the lumbar spine.  相似文献   
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