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51.
BACKGROUND: Many angiotensin II type 1 receptor blockers (ARBs) are available for clinical use, but because they do not all have the same effects, the present study investigated whether all benefits conferred by ARBs are class effects. METHODS AND RESULTS: Study 1 was a case-control study of patients with coronary artery disease, which showed that a non-depressor dose of valsartan significantly decreased the rate of target lesion revascularization at 6 months after stenting compared with the control group without ARB treatment. In Study 2, 44 patients with acute myocardial infarction who randomly received an initial lower dose of either valsartan or losartan after stenting were evaluated. The late loss and decrease in %diameter stenosis in the valsartan group were significantly lower than those in the losartan group as assessed by quantitative coronary angiography after 6 months. In addition, the valsartan group showed a significantly lower expression of intracellular adhesion molecule-1 and L-selectin. CONCLUSION: A non-depressor dose of ARB may have beneficial effects on coronary restenosis that are associated with the regulation of adhesion molecules, and these effects might not be a class effect of ARBs.  相似文献   
52.
The present study evaluated the risk in cardiac patients of rupture of a plaque by a jet stream from the arch cannula. The entire thoracic aorta and cardiac function were routinely monitored by transesophageal echocardiography (TEE) in 88 adult patients who underwent coronary artery bypass surgery. The changes in the atheromatous plaque in the distal aortic arch were observed before and after cardiopulmonary bypass. Of the 88 patients, 13 were found to have preoperative atheromatous plaque at the distal aortic arch and 8 (61.5%) of them suffered plaque rupture caused by jet stream from the arch cannula. Only 1 patient experienced apparent embolic episodes manifesting as cerebral and left leg embolisms; the remaining 7 had no clinical embolic symptoms. In order to prevent atheroembolic events, attention should be paid not only to the ascending aorta, but also to the distal arch and in this regard TEE is useful for detecting atheromatous changes of the aorta.  相似文献   
53.
BACKGROUND/AIMS: The role of trace elements in liver fibrosis, carcinogenesis and progression of hepatocellular carcinoma (HCC) has not yet been clarified. The aim of this study is to analyze the characteristics of trace elements in liver cancers and non-cancerous liver and to discuss their role in hepatic fibrosis, hepatocarcinogenesis and progression of HCC. METHODOLOGY: The amount of zinc (Zn), iron (Fe), and copper (Cu) in 20 HCCs, 2 cholangiocellular carcinomas (CCC), 7 metastatic liver cancers (Meta) and their non-tumorous liver parenchyma were measured using an atomic absorption spectrophotometer. RESULTS: The amounts of Zn and Fe in non-tumorous liver parenchyma were reduced by liver fibrosis, and the amounts were lower in HCC tissue compared to non-tumorous liver parenchyma. The amounts of Zn and Cu were higher in HCC than the amounts found in CCC and Meta. The amount of Zn in HCC tissue decreased, but the amount of Fe increased in tumors more than 4cm in diameter. CONCLUSIONS: These results suggest that the decrease in the amount of Zn and Fe found in non-tumorous liver parenchyma correlates with liver fibrosis leading to cirrhosis and hepatocarcinogenesis. Also that decreases in Zn and increases of Fe in HCC tissue correlates with HCC tumor progression.  相似文献   
54.
55.

Background

It is well known that ultrasound-guided needle-aspiration (USGNA) for intrapulmonary subpleural lesion in contact with the pleura is useful and safe, and its diagnostic yield is high. However, reports concerned with the analyses of cases with intrapulmonary subpleural lesion which could not be diagnosed using USGNA are limited. The objective of this study is to clarify the radiological properties of subpleural primary lung cancer which obstruct diagnosis by USGNA.

Methods

The consecutive cases with subpleural primary lung cancer whose radiological properties could be confirmed by thoracic computed tomography (CT) without contrast enhancement (CE), and examined by USGNA at our hospital between January 1999 and December 2014 have been analyzed. All cases were given pathological diagnoses of primary lung cancer. The diagnostic yield by USGNA was calculated, and the properties of the lesions of the subjects were analyzed by means of thoracic CT without CE images and pathological findings.

Results

87 consecutive cases (41–86 year olds, 75 males, 12 females) were analyzed. The overall diagnostic yield by USGNA was 86.2%. There was no statistically significant difference regarding the diagnostic yield concerning radiological properties such as cavities, small airspaces and low density areas in the lesions and their sizes. However, the diagnostic yield for the cases with squamous cell carcinoma was statistically significantly low (p=0.02).

Conclusion

Although the diagnostic yield of USGNA is not distorted by the radiological properties of lesions, it is statistically significantly low in cases with squamous cell carcinoma.  相似文献   
56.
57.
Purpose: We analyzed the time-course of changes in the sensitivity of total (proliferating + quiescent and quiescent (Q) cell populations within solid tumors in situ following a neutron capture reaction and compared it with that after γ-ray irradiation. Methods: After continuous labeling of proliferating cells with BrdU for 5 days, mice bearing SCC VII tumors received thermal neutron irradiation with or without a 10B-labeled compound (sodium [10B]borocaptate, BSH, or dl-p-[10B]boronophenylalanine, BPA), or γ-ray irradiation. From 5 min to 72 h after treatment, tumors were excised, minced, and trypsinized. Cell suspensions were incubated for 48 h with the cytokinesis blocker cytochalasin-B. The micronucleus frequency for BrdU-unlabeled cells, Q cells at treatment, was then determined by immunofluorescence staining for BrdU. The micronucleus frequency for total cells was obtained from tumors that had not been pretreated with BrdU labeling. The sensitivity was evaluated in terms of the frequency of induced micronuclei in binuclear tumor cells (micronucleus frequency). Results: Overall, Q cells showed greater repair capacities than total cells. γ-Ray irradiation and neutron irradiation with BPA induced larger repair capacities in each cell population. In contrast, thermal neutron irradiation without a 10B-labeled compound induced the smallest repair capacity in both cell populations. The use of a 10B-labeled compound, especially BPA, widened the difference in sensitivity between total and Q cells, resulted in an increase in repair capacity in both cell populations, and made the repair patterns of the two cell populations look like those induced by γ-ray irradiation. Conclusion: Differences in sensitivity and repair patterns following the neutron capture reaction were thought to depend on differences in the distribution of the 10B-labeled compound between the proliferating and Q cell populations. Received: 18 February 1999 / Accepted: 4 June 1999  相似文献   
58.
59.
Angiotensin II (Ang II) evokes inflammatory responses and plays a central role in atherosclerosis mediated by Ang II type 1 (AT1) receptor. AT1 receptor blockers (ARBs) prevent the diverse effects of Ang II. Unique molecule-specific, or off-target effects of ARBs are due to their slightly different structures, although all ARBs have common, or class, effects. In nonsignificant coronary stenotic lesions, it is important that we use aggressive medical treatments using ARBs in addition to statins and oral hypoglycemic agents, to induce the regression and stabilization of coronary plaque. This review focuses on current evidence regarding the molecule-specific effects of ARB olmesartan to prevent the increase in coronary atheroma volume.  相似文献   
60.
A 44-year-old male was pointed out liver function abnormality by medical check-up. Blood examination and computed tomography showed liver cirrhosis. Then, he was referred to our hospital for further examination. After blood test, viral markers revealed previous infection of hepatitis B virus (HBV). We estimated the etiology of his liver disease as previous HBV infection. On laparoscopic examination, his liver surface was nodular with mixed yellowish nodules and ash gray to copper-colored nodules in the diameter of 3–10 mm. There were large regenerative nodules in segments 3 and 4. Large regenerative nodules and irregular steatosis were contradictory to HBV-related liver cirrhosis, so then we supposed Wilson’s disease. The amount of copper excretion in the urine was 326.6 μg (>100 μg/24 h). After D-penicillamine administration, urinary copper excretion increased to 2151.5 μg/24 h. Though hepatic copper concentration was 174.5 μg/g wet tissue (>200 μg/g wet tissue), his laboratory data fulfilled the Leipzig diagnostic criteria proposed by EASL. Laparoscopic examination with liver biopsy has advantages to survey many disease-specific findings on liver surface and to obtain adequate liver sample. Laparoscopic examination is one of the effective procedures for diagnosing relatively rare liver disease like Wilson’s disease.  相似文献   
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