Biomedical subjects

M Takaoka

Publications and source records attributed to M Takaoka.

At least 55 records · Page 3Linked to original sources

PubMed1999

Granulocyte colony-stimulating factor ameliorates life-threatening infections after combined therapy with barbiturates and mild hypothermia in patients with severe head injuries.

OBJECTIVE: The objective of this study was to clarify the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) administration on infections in patients with severe head injuries after combined therapy with high-dose barbiturates and mild hypothermia. PATIENTS AND METHODS: Since 1996, we have administered rhG-CSF to eight patients with severe head injuries for 5 days (group G). Their treatment results were compared with those of 22 patients cared for earlier without rhG-CSF treatment (group N). All patients in both groups met the criteria of total leukocyte count (TLC) less than 5,000/mm3, C-reactive protein (CRP) over 10 mg/dL, and the presence of an infectious complication. Changes in the TLC, CRP, respiratory index, intracranial pressure, and infectious condition were evaluated in both groups. In addition, the nucleated cell count and differentiation from bone marrow aspiration, neutrophil functions, serum concentrations of interleukin-6, and plasma concentration of leukocyte elastase were evaluated in group G. RESULTS: In group G, TLC, nucleated cell count, and neutrophil functions significantly increased, whereas CRP, respiratory index, and interleukin-6 decreased reciprocally. There was no deterioration of intracranial pressure and leukocyte elastase. Consequently, seven of the eight patients in group G recovered from life-threatening infections, and none of the eight patients died. However, in group N, CRP and respiratory index remained high and TLC did not increase as much as it did in group G. Infections continued after 5 days in 17 of the 22 patients, 7 of whom died from severe infections during hospitalization. CONCLUSION: Administration of rhG-CSF ameliorated life-threatening infections without causing lung injury or increasing brain swelling in patients with severe head injuries who were treated with combined therapy involving high-dose barbiturates and mild hypothermia.

Adolescent↗

PubMed1999

Different contributions of endothelin-A and endothelin-B receptors in the pathogenesis of deoxycorticosterone acetate-salt-induced hypertension in rats.

We investigated the involvement of actions mediated by endothelin-A (ETA) and endothelin-B (ETB) receptors in the pathogenesis of deoxycorticosterone acetate (DOCA)-salt-induced hypertension in rats. Two weeks after the start of DOCA-salt treatment, rats were given ABT-627 (10 [mg/kg]/d), a selective ETA receptor antagonist; A-192621 (30 [mg/kg]/d), a selective ETB receptor antagonist; or their vehicle for 2 weeks. Uninephrectomized rats without DOCA-salt treatment served as controls. Treatment with DOCA and salt for 2 weeks led to a mild but significant hypertension; in vehicle-treated DOCA-salt rats, systolic blood pressure increased markedly after 3 to 4 weeks. Daily administration of ABT-627 for 2 weeks almost abolished any further increases in blood pressure, whereas A-192621 did not affect the development of DOCA-salt-induced hypertension. When the degree of vascular hypertrophy of the aorta was histochemically evaluated at 4 weeks, there were significant increases in wall thickness, wall area, and wall-to-lumen ratio in vehicle-treated DOCA-salt rats compared with uninephrectomized control rats. The development of vascular hypertrophy was markedly suppressed by ABT-627. In contrast, treatment with A-192621 significantly exaggerated these vascular changes. In vehicle-treated DOCA-salt rats, renal blood flow and creatinine clearance decreased, and urinary excretion of protein, blood urea nitrogen, fractional excretion of sodium, and urinary N-acetyl-beta-glucosaminidase activity increased. Such damage was overcome by treatment with ABT-627 but not with A-192621; indeed, the latter agent led to worsening of the renal dysfunction. Histopathologic examination of the kidney in vehicle-treated DOCA-salt rats revealed tubular dilatation and atrophy as well as thickening of small arteries. Such damage was reduced in animals given ABT-627, whereas more severe histopathologic changes were observed in A-192621-treated animals. These results strongly support the view that ETA receptor-mediated action plays an important role in the pathogenesis of DOCA-salt-induced hypertension. On the other hand, it seems likely that the ETB receptor-mediated action protects against vascular and renal injuries in this model of hypertension. A selective ETA receptor antagonist is likely to be useful for treatment of subjects with mineralocorticoid-dependent hypertension, whereas ETB-selective antagonism alone is detrimental to such cases.

Animals↗

PubMed1999

Relationship between brain atrophy estimated by a longitudinal computed tomography study and blood pressure control in patients with essential hypertension.

To evaluate the relationship between blood pressure control and the progression of brain atrophy in the elderly, patients with essential hypertension and brain atrophy were longitudinally evaluated using computerized tomography (CT). The study evaluated 48 patients with essential hypertension aged 46-78 years, and 30 sex- and age-matched normotensive control subjects. The extent of brain atrophy as determined by caudate head index (CHI), the inverse cella media index (iCMI), and Evans' ratio (ER) was estimated twice at an interval of 5-9 years (mean, 6.9 years). The mean annual increases in CHI (deltaCHI), iCMI (delta iCMI), and ER (deltaER) were evaluated. Mean blood volume in the common carotid artery (BF) and the decrease in BF per year (deltaBF) were also determined. The deltaCHI, delta iCMI, and deltaER increased with age in the hypertensive subjects as well as the control group across all age groups evaluated. The deltaCHI, delta iCMI, and deltaER were significantly greater in the patients with essential hypertension in their 50 s as compared with the controls. In patients with essential hypertension aged 65 years or older, the deltaCHI, delta iCMI, and deltaER were significantly lower in the group in whom the blood pressure was controlled within the range of borderline hypertension than the groups in which it was controlled in the range of normal or mild hypertension. In the younger patients under the age of 65 with essential hypertension, blood pressure control did not affect the deltaCHI, delta iCMI, and deltaER. The deltaCHI, delta iCMI, and deltaER were significantly correlated with deltaBF in both groups. These findings indicate that control of systolic blood pressure within the range of borderline hypertension may delay the progression of brain atrophy in elderly patients with essential hypertension.

Aged↗

PubMed1999

Protective effect of KB-R7943, a novel Na+/Ca2+ exchange inhibitor, on ischemic acute renal failure in rats.

The effects of KB-R7943 (2-[2-[4-(4-nitrobenzyloxy)phenyl]ethyl]isothiourea methanesulfonate), a novel Na+/Ca2+ exchange inhibitor, on ischemic acute renal failure (ARF) in rats were examined. ARF was induced by clamping the left renal pedicle for 45 min followed by reperfusion, 2 weeks after contralateral nephrectomy. Renal function was markedly diminished in ARF rats. Pretreatment with KB-R7943 (10 mg/kg, i.v.) markedly attenuated the ARF-induced renal dysfunction. Histopathological examination of the kidney of ARF rats revealed severe renal damage, which was suppressed by KB-R7943. Activation of the reverse mode of Na+/Ca2+ exchange seems to play an important role in the pathogenesis of ARF. A selective Na+/Ca2+ exchange inhibitor may be useful in cases of ARF.

Acute Kidney Injury↗

PubMed1999

Asymptomatic cerebrovascular lesions detected by magnetic resonance imaging in patients with systemic lupus erythematosus lacking a history of neuropsychiatric events.

OBJECTIVE: To clarify the extent of asymptomatic cerebrovascular involvement in systemic lupus erythematosus (SLE). PATIENTS AND METHODS: Cerebral magnetic resonance imaging (MRI) findings and ultrasonography findings of 100 patients with SLE lacking present or past clinical neurologic deficits were compared with 66 age-matched volunteers to determine the combined intima-media thickness (IMT) of the common carotid artery, and tests for anti-cardiolipin antibodies (aCL). RESULTS: Thirty-eight patients, but only 2 controls, showed imaging abnormalities. Among 23 SLE patients with cerebrovascular lesions by MRI who underwent single-photon emission computed tomography (SPECT), 14 showed hypoperfusion of the lesion. The IMT value and prevalence of aCL did not differ between the 55 SLE patients tested and controls. SLE disease activity index (SLEDAI) as assessed by a quantitative clinical index was significantly greater in patients with brain lesions than in those without. CONCLUSION: The prevalence of asymptomatic brain lesions in SLE patients is highs and shows a relationship to disease activity.

Adolescent↗

PubMed1998

A proteasome inhibitor lessens the increased aortic endothelin-1 content in deoxycorticosterone acetate-salt hypertensive rats.

Deoxycorticosterone acetate (DOCA)-salt-treated rats developed marked hypertension after 4 weeks with an increase in aortic endothelin-1. Treatment of DOCA-salt hypertensive rats with a proteasome inhibitor, N-benzyloxycarbonyl-Ile-Glu(O-t-Bu)-Ala-leucinal, significantly reduced the elevation in systolic blood pressure and the effect was accompanied by a decrease in aortic endothelin- content. Thus, a proteasome-dependent proteolytic pathway appears to play an important role in the enhanced production of endothelin-1 in blood vessels and the consequent increase in blood pressure in this model of hypertension.

Animals↗

PubMed1998

Influence of biliary obstruction on neutrophil chemotaxis.

The effect of obstructive jaundice on neutrophil chemotactic function was investigated, with a potent chemotactic factor, IL-8 (recombinant rat GRO-beta), in rats that received 7-day bile duct ligation. Carrageenin or IL-8 was injected into a preformed air pouch, and exudate was collected 4 h later for measurement of myeloperoxidase activity. In vitro chemotaxis of peripheral neutrophils to IL-8 was evaluated by a modified Boyden chamber method. Both carrageenin and IL-8 induced significantly pronounced intra-air pouch neutrophil recruitment in the bile duct-ligated group compared with a sham-ligated group. In vitro neutrophil chemotaxis was significantly increased in the bile duct-ligated group compared with the sham-ligated group. The present experimental model suggests enhanced neutrophil chemotaxis to IL-8 in obstructive jaundice.

Animals↗

PubMed1998

Antihypertensive effect of a proteasome inhibitor in DOCA-salt hypertensive rats.

To search for a possible role for vascular proteasome in hypertension, we examined changes in proteasome level in aorta of deoxycorticosterone acetate (DOCA)-salt hypertensive rats and evaluated the antihypertensive effect of a proteasome inhibitor, N-benzyloxycarbonyl-Ile-Glu(O-t-Bu)-Ala-leucinal (PSI). Two weeks after the start of DOCA-salt treatment, the rats, with systolic blood pressure being 154 +/- 5 mmHg, were randomly divided into two groups and were given PSI or its vehicle for 2 weeks. Vehicle-treated DOCA-salt rats developed marked hypertension after 4 weeks (198 +/- 9 mmHg), with increases in aortic proteasome activity and content. The systolic blood pressure was positively correlated with both the content and activity of aortic proteasome. The administration of PSI to DOCA-salt hypertensive rats suppressed the elevation of systolic blood pressure (144 +/- 4 mmHg), accompanied by decreases in aortic proteasome activity and content. These results suggest that proteasome production in vascular tissues is increased in DOCA-salt hypertensive rats, and that PSI exhibits antihypertensive effect in this experimental hypertensive model. Thus, the findings indicate the pathophysiological importance of increased vascular proteasome in the development of DOCA-salt hypertension.

Animals↗

PubMed1998

Effect of obstructive jaundice on neutrophil chemotactic activity: an in vivo assessment in zymosan-induced peritonitis model in rats.

The effect of obstructive jaundice on local neutrophil accumulation in response to inflammatory stimulus was investigated in rats. Obstructive jaundice was produced by bile duct ligation for 7 days. Zymosan (200 mg) was injected intraperitoneally and 4h later myeloperoxidase activity in the peritoneal fluid was measured to quantify neutrophil recruitment. Zymosan-induced neutrophil recruitment was significantly greater (more than two-fold) in bile duct-ligated rats than in sham-ligated or normal animals. Depletion of peritoneal cells significantly suppressed neutrophil recruitment after zymosan injection in all three groups, with no significant differences between the groups. In normal rats, replacement of their peritoneal cells by those from bile duct-ligated rats did not enhance zymosan-induced neutrophil recruitment. In contrast, bile duct-ligated rats treated with peritoneal cell replacement from normals showed significantly increased neutrophil recruitment after zymosan injection. In vitro neutrophil chemotaxis in response to formyl-Met-Leu-Phe was significantly enhanced in bile duct-ligated rats, compared with that in sham-ligated animals. The results suggest that local neutrophil recruitment in response to inflammation may be enhanced in obstructive jaundice and that increased neutrophil chemotactic activity, not macrophage activity, may play a prime role in the mechanism.

Animals↗

PubMed1998

Pentoxifylline attenuates reperfusion injury in skeletal muscle after partial ischemia.

Leukocytes have been shown to contribute to ischemia-reperfusion injury in skeletal muscle. Pentoxifylline (PTXF), a xanthine-derived phosphodiesterase inhibitor, has received recent attention because of its action on leukocytes. To clarify the effects of PTXF in reperfusion injury, we measured the resting transmembrane potential difference (Em) and evaluated postcapillary venule microcirculation using intravital microscopy in rat skeletal muscle during ischemia and reperfusion. The infrarenal aorta was clamped for 90 min and then reperfused for 60 min. Persistent depolarization of the resting Em was observed in an ischemia-reperfusion (IR) group and was significantly repolarized in a PTXF group during the reperfusion period. The tissue water content was significantly reduced in the PTXF group, although no difference was noted in the tissue lactate content. Flowing erythrocyte velocity and wall shear rate in the PTXF group were significantly higher than in the IR group during the reperfusion period but without significant differences in vessel diameter and hemoglobin oxygenation. Blood flow measured by laser-Doppler flowmeter was also significantly improved in the PTXF group. Furthermore, the adherent leukocyte count was significantly reduced in the PTXF group during this same period. These results indicate that PTXF attenuated reperfusion-associated membrane injury and tissue edema and that PTXF suppressed leukocyte adhesion and improved hindlimb blood flow during the reperfusion period.

Animals↗

PubMed1998

[Hemodynamics of asymptomatic brain infarction determined by Doppler sonography].

We compared the usefulness of two methods for diagnosing asymptomatic brain infarction: an ultrasonic quantitative flow measurement system (QFM) and a transcranial Doppler arteriography (TCDA). A total of 137 patients (73 men and 64 women) who underwent magnetic resonance imaging of the brain, QFM, and TCDA were enrolled. Their ages ranged from 41 to 83 years (mean age, 63 years). The patients were divided into 3 groups: 45 without cerebrovascular disease (Group N); 40 with asymptomatic brain infarction (Group AS); and 52 with lacunar infarction (Group LI). The mean blood flow in the common carotid artery (CCA-BF) was measured by QFM. The mean blood velocity and Fourier pulsatility index in the middle cerebral artery (MCA-BV, MCA-PI) were measured by TCDA. In Group N, 28 patients were examined twice at a mean interval of 2 years; 19 remained without asymptomatic brain infarction (Group N1), and asymptomatic brain infarction developed in the remaining 9 (Group N2). The 3 groups differed significantly in MCA-PI (N < AS < LI), but not in CCA-BF or in MCA-BV. The MCA-PI in Group N2 was higher than that in Group N1. These results indicate that the Fourier pulsatility index determined by TCDA may be useful for detecting the onset of asymptomatic brain infarction.

Adult↗

PubMed1998

[Carotid artery atherosclerosis in patients with myocardial infarction].

This study investigated carotid artery atherosclerosis in patients with myocardial infarction. One hundred and two patients with acute myocardial infarction [Group MI: male 86, female 16, mean 62 (range 43-79) years] and 55 normal subjects matched for age and sex with negative responses to exercise electrocardiogram testing (control group: Group C) were included. Patients in Group MI were divided into 3 subgroups according to coronary angiographic findings as follows: 57 patients with one-vessel disease (Group I: mean 59 years), 34 with 2-vessel disease (Group II: mean 64 years), and 11 with 3-vessel disease (Group III: mean 64 years). Intima-media complex thickness (IMT) of the bilateral common carotid arteries (15 mm proximal to the bifurcation) and the internal carotid arteries (15 mm distal to the bifurcation) were measured by high-resolution B-mode ultrasonography, and the sum of maximum IMT of the bilateral carotid arteries (sigma IMT) were calculated. sigma IMT was significantly greater in Group MI (2.5 +/- 0.5 mm) than in Group C (1.8 +/- 0.3 mm), sigma IMT was 2.5 +/- 0.5 in Group I, 2.6 +/- 0.5 in Group II, and 2.7 +/- 0.4 mm in Group III. There was a significant positive correlation between sigma IMT and the number of involved vessels (tau = 0.45, p < 0.01). The percentage of patients with carotid artery atherosclerosis was 2% in Group C, 63% in Group MI, 54% in Group I, 68% in Group II, and 82% in Group III (p < 0.001). This study suggests that carotid artery atherosclerosis in patients with myocardial infarction is frequently complicated and severe, and more frequently complicated in patients with severe coronary artery disease.

Adult↗

PubMed1997

Platelets enhance contractility in perfused rat mesenteric arteries: involvement of endothelin-1.

We investigated the effects of platelet supernatant on pressor responses to norepinephrine in isolated perfused rat mesenteric arteries. Perfusion of the arteries with platelet supernatant for 2 h markedly enhanced the pressor responses to norepinephrine (10(-6) and 3 x 10(-6) M). This enhancement was significantly inhibited by phosphoramidon (10(-4) M), an endothelin converting enzyme inhibitor. Both BQ788 [N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-methylleucyl-D -1-methoxycarbonyltryptophanyl-D-norleucine] (10(-6) M), an endothelin ET(B) receptor antagonist, and bosentan (Ro47-0203, 4-tert-butyl-N-[6-(2-hydroxy-ethoxy)-5-(2-methoxy-phenoxy)-2,2-bipyri midin-4-yl]-benzenesulfonamide) (10(-5) M), a nonselective endothelin receptor antagonist, also prevented the potentiation of responses to norepinephrine evoked by platelet supernatant, but FR 139317 ((R)2-[(R)-2-[(S)-2-[[1-(hexahydro-1H-azepinyl)]carbonyl]amino-4-+ ++methylpentanoyl] amino-3-[3-(1-methyl-1H-indoyl)]propionyl]amino-3-(2-pyridyl) propionic acid) (10-6 M), an endothelin ET(A) receptor antagonist, had little effect. Suppressor doses of endothelin-1 (3 x 10(-10) M) or sarafotoxin S6c (S6c) (3 x 10(-10) M) potentiated significantly the norepinephrine-induced vasoconstriction, in the same preparation. Moreover, supernatant-induced enhancement of pressor responses to norepinephrine was markedly suppressed by TGF-beta1 neutralizing antibody. Transforming growth factor-beta1 (TGF-beta1) (40 pM) also significantly enhanced the pressor responses to norepinephrine (10(-6) M) and this enhancement was significantly inhibited by phosphoramidon. These results suggest that platelet-derived TGF-beta1 stimulates the vascular production of endothelin-1 and thereby enhances vasoconstrictor responses to norepinephrine. Platelet-induced enhancement of vasoconstrictor responses to norepinephrine seems to be mainly mediated by endothelin ET(B) receptor, in rat mesenteric arteries.

Animals↗

PubMed1997

Fluid resuscitation and systemic complications in crush syndrome: 14 Hanshin-Awaji earthquake patients.

BACKGROUND: Crush syndrome is a form of traumatic rhabdomyolysis characterized by systemic involvement, in which acute renal failure is potentially life-threatening. METHODS: Clinical and laboratory data of 14 crush-syndrome patients transferred to a tertiary emergency department after the Hanshin-Awaji earthquake were analyzed. The patients were buried under collapsed houses for the average of 6.7 +/- 5.7 (SD) hours (range, 1 to 24 hours). They were referred to us 6 to 250 hours after the earthquake. RESULTS: Of those who arrived at our institution within 40 hours, 25% (two of eight) developed renal failure, whereas all six patients who arrived after 40 hours developed renal failure. Peak serum creatine kinase ranged from 6,677 to 134,200 U/L (51,674 +/- 41,776). Renal failure was highly associated with massive muscle damage (serum creatine kinase above 25,000 U/L) and insufficient initial fluid resuscitation (below 10,000 mL/2 days). CONCLUSIONS: Prompt and adequate, if not massive, fluid resuscitation is the key to preventing renal failure after such injury.

Creatine Kinase↗

PubMed1997

Analysis of 2,702 traumatized patients in the 1995 Hanshin-Awaji earthquake.

BACKGROUND: This study was undertaken to define the factors that affected the final outcome of trauma patients in the Hanshin-Awaji earthquake. METHODS: Medical records of patients admitted to 95 hospitals within or surrounding the affected area during the first 15 days after the quake were reviewed. RESULTS: There were 2,702 traumatized patients. One-third of the patients were transported to hospitals in the surrounding area and had a mortality rate of 3%. The remainder, who were treated in the affected hospitals, showed a significantly higher mortality rate (8%; p < 0.05). Intensive care was provided for 513 patients, most of whom suffered from crush syndrome or from injuries to vital organs; these patients had a high mortality rate. Patients with other types of injuries had a lower mortality rate. CONCLUSION: Crush syndrome and injuries to vital organs were potentially life-threatening. We believe that early transportation of such patients to undamaged hospitals with the ability to provide intensive care would have improved the survival rate.

Abbreviated Injury Scale↗

PubMed1997

[Relationship between carotid atherosclerosis and plasma endothelin-1 concentration in senile patients with hypertension].

The relationship between carotid atherosclerosis and plasma endothelin-1 (ET-1) concentration was studied in senile patients with essential hypertension. A total of 212 patients (83 M, 129 F; mean age, 63 years) with essential hypertension (WHO stage I-II), and 109 age-matched control subjects (mean age, 61 years) were enrolled in the study. The maximum thicknesses of the intima-media complex (IMTmax) in the right common carotid artery (CCA) and the right internal carotid artery (ICA) was measured by B-mode ultrasonography, and ET-1 was measured by enzyme immunoassay. ET-1 levels were significantly higher in the hypertensive patients than in the control subjects. In middle-aged patients (35-64 years old), IMTmax values of the ICA in patients with high ET-1 concentrations (ET-1 > or = 1.71 pg/ml) were significantly higher than in patients with normal ET-1 concentrations (ET-1 < 1.71 pg/ml). However, the IMTmax of the CCA did not show a similar correlation. In senile patients (65-83 years old), both the CCA and ICA IMTmax values were significantly higher in patients with high ET-1 concentrations than in those with normal ET-1 concentrations. These results indicate that high ET-1 levels in middle-aged patients with essential hypertension may play a role in the progression of ICA atherosclerosis. High ET-1 levels in senile patients with essential hypertension may cause progression of atherosclerosis in both the ICA and CCA.

Adult↗

PubMed1997

[The relationship between brain atrophy and asymptomatic cerebral lesions].

In order to clarify the relationship between brain atrophy and asymptomatic cerebral lesions, total of 235 subjects (130 males and 105 females), who had neither neurologic deficits nor organic lesions on cerebral computed tomography, were studied. The subjects' ages ranged from 40 to 86 years (mean 66). They were divided into two groups: 90 controls without hypertension or diabetes mallitus (Group C), and 145 patients with essential hypertension (Group H). Brain atrophy was diagnosed using the caudate head index (CHI). Asymptomatic cerebral lesions on magnetic resonance imaging were defined as asymptomatic lacunae and white matter lesions. Caudate head index was higher in Group H than it was in Group C, and CHI in both groups was significantly correlated with the number of asymptomatic lacunae and the severity of white matter lesions on magnetic resonance imaging. These results indicate that brain atrophy may progress along with asymptomatic cerebral lesions.

Adult↗

PubMed1997

[Effects of long-term antihypertensive medication on common carotid hemodynamics in elderly patients with essential hypertension].

This longitudinal study was performed in order to clarify the effects of long-term antihypertensive medication on common carotid hemodynamics. A total of 84 patients (54 males and 30 females), who had been receiving treatment with antihypertensive medications for 5 years, were enrolled in this study. The subjects' ages ranged from 62 to 74 (mean 67). They were divided into three groups: 40 were treated with diuretics only (Group D), 28 with calcium antagonists only (Group C), and 16 with angiotensin converting enzyme inhibitors only (Group A). Mean blood flow volume (BF) and circulation resistance (Z) at the common carotid artery were measured by an ultrasonic quantitative flow measurement system. Blood flow volume, Z, and mean blood pressure (MBP) were measured twice over a 5-year period in patients and in 49 age-matched normal controls (Group N). Annual reductions in BF (delta BF) and MBP (delta MBP), and annual increases in Z (delta Z) were calculated. Blood flow volume of Group D showed larger decreases than that of the other three groups. Circulation resistance of Group C showed smaller increases than that of Group N. Reductions of BF and Z of Group A were similar to those of Group N. Reductions of Z of Group C showed a significant correlation with delta MBP. These results indicate that calcium antagonists may have beneficial effects on common carotid hemodynamics in elderly patients with essential hypertension.

Aged↗