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61.
We report a 54-year-old Japanese woman who developed liver tumors 102 months after hepatic resection for hepatocellular carcinoma (HCC) and percutaneous transluminal angioplasty (PTA) for membranous obstruction of the inferior vena cava (MOVC), which is one form of Budd-Chiari syndrome. In the present admission workup showed no evidence of co-infection with hepatitis B and C viruses. Dynamic computed tomography (CT) and magnetic resonance imaging showed an enhanced lesion, 1.5cm in diameter, in segment 3 of the liver, and no obstruction of the inferior vena cava after PTA. CT during both arterial portography and hepatic arteriography revealed another lesion, showing different hemodynamics, in segment 2. The patient therefore underwent hepatic resection, and the tumors were diagnosed histologically as HCC. The two tumors differed in their morphological features, one containing abundant fibrous stroma, whereas the other did not. The nontumorous liver tissue showed central zonal fibrosis, i.e., reversed lobulation, and partial expansion of nodule-like formations, indicating lack of progression since the situation seen at the initial hepatectomy. The presence of nontumorous liver tissue showing the above features suggests that, even after successful treatment for relief of congestion, patients who have had MOVC should be followed closely for as long as possible because of the risk of HCC recurrence. This is the first reported case of HCC recurrence after successful treatment of MOVC.  相似文献   
62.
63.
Summary A placebo-controlled, double-blind crossover study was undertaken in 10 normal subjects to examine the effects of arotinolol (10 mg bid), a nonselective beta blocker with alpha-blocking activity, on exercise capacity and hormone levels during exercise after a 2-week treatment period. Maximal oxygen uptake (VO2 max) and blood lactic acid concentration (LA) were measured during progressive exercise testing. An exercise intensity equivalent to 4 mmol/l of LA was used for the constant workload exercise test. Humoral factors were measured after 20 minutes of constant workload exercise. The administration of arotinolol significantly decreased systolic blood pressure and heart rate at rest and during exercise, but diastolic blood pressure did not change. No significant difference was found between arotinolol and placebo with regard to VO2 max and maximal workload. Plasma renin activity (PRA), aldosterone (PAC), and norepinephrine (NE) levels at rest and during exercise did not differ between the two treatments. In contrast, plasma epinephrine (EN) levels at rest and during exercise were significantly greater with arotinolol. Atrial natriuretic peptide (ANP) at rest did not differ between the two treatments. However, exercise caused a significant increase in ANP after arotinolol treatment. These findings suggest that arotinolol decreases blood pressure and heart rate without affecting exercise capacity.  相似文献   
64.
Typical angioid streaks were found on routine ophthalmologic examination in a 42-year-old female with yellowish, coalescing papules on her neck without any symptoms. Biopsy of the cutaneous lesion showed degeneration and fragmentation of the elastic fibers and many basophilic-stained calcifications in mid-dermis, which are consistent with pseudoxanthoma elasticum. Twenty-four-hour Holter electrocardiography (ECG) showed sinus arrest for 2.5 seconds, and an electrophysiological study revealed sinus nodal dysfunction (sick sinus syndrome), whereas all of the coronary arteries were intact, despite a treadmill stress ECG test showing significant ST depressions. The association of pseudoxanthoma elasticum and sick sinus syndrome is very rare. One possible explanation for this association here is that the degeneration of elastic fiber in endomysium of the sino-atrial node may have affected heart conduction systems, resulting in sick sinus syndrome.Part of this work was presented at the 76th Japanese Circulation Society Kyushu Meeting, Japan, June 18, 1994  相似文献   
65.
66.
To characterize rT3 5'-deiodinase (5'D) in rat skeletal muscle, the effects of altered thyroid status and PTU on rT3 5'D were studied. rT3 5'D activity was measured by incubating homogenates of rat skeletal muscle with [125]rT3, iodine labelled in the outer ring, in the presence of 20 mmol/l DL-dithiothreitol. This activity was observed to increase significantly 24 h after a single sc injection of T3 (75 micrograms/kg). The increase following the daily administration of this drug (15 or 75 micrograms/kg) for 3 and 14 days was dependent on the dose and number of previous days of injection. A significant decrease in activity was observed 2 weeks after thyroidectomy. The addition of 0.1 mmol/l 6-n-propyl-2-thiouracil (PTU) to the incubation medium in vitro caused a marked reduction in the activity in homogenates of skeletal muscle from hypothyroid, euthyroid and hyperthyroid rats. PTU, present at 0.05% in the drinking water for 2 weeks virtually abolished it. The properties of rT3 5'D in rat skeletal muscle thus appear to be essentially the same as those of type I enzyme with respect to response toward altered thyroid status and PTU.  相似文献   
67.
Four kinds of human cancer cell lines and one mouse cancer cell line were inoculated into the subepithelial area of the anorectum of female nude mice. Among the cell lines, two cell lines (KATO III and Lu 135) showed the potential enforcement of atypical changes in the adjacent mouse anorectal epithelium. Moreover, the submucosal invasion of the malignant transformed cells of the mouse epithelium was demonstrated in specimens obtained from three KATO III-inoculated mice. This exciting and novel phenomenon clearly demonstrates the need to change the present general concept of a single-cell origin of cancer tissue. This valuable and novel discovery may change the basis of oncology research while also providing new ideas for projects to investigate the mechanisms of carcinogenesis from several aspects such as molecular biology, cell biology, and pathology. Moreover, the novel experimental design itself is also extremely useful as a simple model for investigating the mechanisms of oncogenesis.  相似文献   
68.
69.
Inflammatory responses in cuff-induced atherosclerosis in rabbits   总被引:3,自引:0,他引:3  
Cuff-treatment of the rabbit carotid artery produced a diffuse intimal thickening which resembled early lesions of atherosclerosis. A limited amount of focal endothelial damage occurred first (0.5 h), leukocytes infiltrated the subendothelium and extensive endothelial denudation occurred at 24 h. At 3 days, the regenerating endothelium covered the denuded area, and the media was edematous. At 7 days proliferation of intimal cells became visible. Maximum intimal thickening occurred at 3 weeks. Daily injection of dexamethasone (0.01-10 mg/kg i.m.) and ticlopidine (1-100 mg/kg i.m.) dose-dependently attenuated the intimal thickening. Indomethacin had little effect. Inflammatory exudate from zymosan-activated air pouch induced chemotaxis of rat smooth muscle cells (SMC) in vitro. Similar chemotactic activity was observed with leukotriene B4 (LTB4) but not with the other lipoxygenase products tested. The exudate contained reasonable amounts of LTB4, which would account for its chemotactic activity. Dexamethasone inhibited the chemotaxis by the exudate and proliferation of SMC. These results are discussed in relation to the mechanism of atherogenesis. It is concluded that leukocytes play a major role in cuff-induced intimal thickening, and that their products cause endothelial denudation and SMC chemotaxis. Involvement of platelet aggregation in atherogenesis is also suggested.  相似文献   
70.

Purpose

To evaluate the value of measuring shear wave velocity evoked by acoustic radiation force impulse (VTTQ) for the risk assessment of hepatocellular carcinoma (HCC) development in patients with nonalcoholic fatty liver disease (NAFLD).

Methods

VTTQ was measured three times in each of the four liver segments in 163 NAFLD patients, including 14 HCC cases; the results were statistically evaluated.

Results

The VTTQ was 3.04 ± 0.17 m/s (median ± median absolute deviation) and 1.27 ± 0.25 m/s in patients with and without HCC, respectively, and was significantly higher in HCC cases (p < 0.001). When the patients were classified as F0–F4 based on VTTQ cutoff values, VTTQ was significantly higher in the left lobe than in the right lobe for F0 (p < 0.0001) and for F1 and F2 combined (p < 0.0001), but not significantly higher for F3 and F4 combined (p = 0.070). The robust coefficient of variation was significantly higher in the left than in the right (p = 0.018) and significantly increased as VTTQ increased (p = 0.0002). Multivariate analysis showed that total bilirubin concentration {p = 0.014, 38.9 (2.08–727) [odds ratio (95 % confidence interval)]} and VTTQ [p = 0.006, 113 (3.91–3245)] were the only independent explanatory factors for HCC presence among the seven variables identified by univariate analysis. The area under the receiver-operating characteristic curve in the differentiation of HCC from non-HCC was 0.943 for VTTQ and was comparable to that for other noninvasive markers such as Fib-4 (0.964) or higher than that in BARD (0.838).

Conclusions

These results suggest that fibrosis occurs heterogeneously throughout the liver and that VTTQ measurements are useful in HCC risk evaluation in a NAFLD cohort.  相似文献   
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