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991.
The interaction of an exogenous PML/RARα fusion gene associated with acute promyelocytic leukaemia, with all- trans retinoic acid (ATRA) was examined in two lymphoid cell lines. L1210 and MOLT-4 cells were transfected with PML/RARα cDNA in the expression vector pGD and stable transformants (L1210 PML/RAR α and MOLT-4 PML/RAR α) were selected with G418. ATRA inhibited the growth of these stable transformants, as assessed by [3H]thymidine incorporation, in a dose-dependent manner, but had no effect on the growth of control cells stably transformed with neomycin resistant gene alone. ATRA also induced apoptosis, as assessed by fragmentation of genomic DNA, in L1210 PML/RAR α and MOLT-4 PML/RAR α cells but not in control cells. The exogenous PML/RARα fusion gene therefore probably mediates the effects of ATRA on cell growth and apoptosis in these cell lines.  相似文献   
992.
There is increasing evidence that peripheral pulse pressure measured at the brachial artery is a good predictor of coronary heart disease. However, the relation between pulse pressure and angiographically demonstrated coronary artery stenosis has not been fully elucidated. We designed the present study to investigate the association of the various components of blood pressure, such as systolic pressure, diastolic pressure, and pulse pressure of both peripheral and central arteries with angiographically determined coronary artery stenosis. Levels of aortic systolic pressure, aortic diastolic pressure, aortic pulse pressure, peripheral systolic pressure, peripheral diastolic pressure, and peripheral pulse pressure were determined in 323 patients who underwent diagnostic coronary angiography. Of these 323 patients, 215 patients had significant organic coronary artery stenosis. Aortic pulse pressure was significantly higher in patients with coronary artery stenosis (P = 0.0050). Aortic diastolic pressure was lower in patients with coronary artery stenosis (marginally significant, P = 0.0462). However, no statistically significant difference was observed between other blood pressure components and coronary artery stenosis. Multivariate analyses showed that aortic pulse pressure was associated with coronary artery stenosis independently of aortic diastolic pressure. Moreover, aortic pulse pressure was positively correlated with the number of vessels involved (P = 0.0024). The results of the present study indicate that aortic pulse pressure is significantly and independently correlated with angiographically determined coronary artery stenosis.  相似文献   
993.
The clinical features of familial Creutzfeldt-Jakob disease with a codon 200 point mutation [fCJD (E200K)] are similar to those of sporadic CJD (sCJD). MRI diffusion-weighted imaging (MRI-DWI) has been reported to be useful for the early diagnosis of CJD. We describe a Japanese fCJD (E200K) case in which thalamic symptoms were the initial manifestations. On admission, electroencephalography (ECG) showed no periodic synchronous discharge (PSD), and MRI showed no abnormalities. However, single photon emission computed tomography (SPECT) using (99m)Tc-ethyl cysteinate dimer ((99m)Tc-ECD) revealed hypoperfusion in the right thalamus. We conclude that the thalamic form of CJD tends to show no high-intensity area (HIA) by MRI-DWI, and that SPECT may be more useful for visualizing the affected area responsible for the thalamic symptoms at an early stage.  相似文献   
994.
In a 43-year-old Japanese Brazilian who came to Japan in 2001, since subjective symptoms such as cough, sputum, and dyspnea on exertion had become severe, he was referred to our hospital because of suspicion of pulmonary tuberculosis in chest radiography and CT findings. A chest radiograph of initial examination showed interstitial shadows in both lungs with nodular, infiltrative or cavitary changes. No Mycobacterium tuberculosis was found. The mycetocyte with multipolar budding resembling the steerage of a ship, which was characteristic of Paracoccidioides was observed in sputum and transbronchial lung biopsy specimens. We cultured a fungus to show dimorphism of temperature dependency, and a diagnosis of chronic lung paracoccidioidomycosis was arrived at. By administration of ITCZ 200 mg/day, the chest radiography findings and clinical manifestations were improved. This case seems to be worthy of reporting in Japan since the affected site or organ was limited to the two lungs with multiple cavitary lesions and fibrotic changes on radiographic examination, and final diagnosis was made by cytology of sputum and pathology of TBLB specimens.  相似文献   
995.
OBJECTIVES: This study evaluated the sensitivity and the related factors in iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) scintigraphy to detect stable angina. METHODS: The subjects were 198 patients with stable angina who underwent BMIPP before percutaneous coronary intervention or coronary bypass graft surgery. Patients with unstable angina, myocardial infarction, congestive heart failure, cardiomyopathy and vasospastic angina were excluded. After investigation of the sensitivity of BMIPP, the patients with single-vessel disease without collateral flow were classified into the normal (123)I-BMIPP uptake group (normal group)or decreased (123)I-BMIPP uptake group (decreased group), and various factors were compared between the two groups. RESULTS: Sensitivity was 61% overall, 58% in single-vessel disease, 69% in double-vessel disease, 53% in triple-vessel disease, 43% in only left main vessel disease, and 89% in left main and other vessel disease (NS). In single-vessel disease, the sensitivity was 40% in 75% coronary artery stenosis, 58% in 90% stenosis, 89% in 99% stenosis, and 69% in total occlusion (p = 0.003). Comparing the deoreased and normal groups, diabetes mellitus was more frequent in the normal group (14.6% vs 39.5%), minimal lumen diameter was smaller (0.75 +/- 0.37 vs 0.98 +/- 0.49 mm) and lesion length was longer in the decreased group (15.4 +/- 4.9 vs 11.6 +/- 5.5 mm). Logistic multivariate analysis showed that the independent factors were diabetes mellitus [odds ratio 0.20, 95% confidence interval (CI) 0.04-0.87, p = 0.03], minimal lumen diameter (odds ratio 0.10, 95% CI 0.02-0.48, p = 0.003) and lesion length (odds ratio 1.12, 95% CI 1.00-1.25, p = 0.03). CONCLUSIONS: BMIPP is useful in stable angina patients because of the acceptable sensitivity. Diabetes mellitus, minimal lumen diameter and lesion length were independent factors associated with decreased BMIPP uptake.  相似文献   
996.
BACKGROUND: It has been reported that recording electrocardiograms (ECGs) in the 3rd intercostal space (ICS) is one method that can be used for detecting Brugada syndrome; however, the prevalence of Brugada-type ECGs recorded in the 3rd ICS and the usefulness of recording the ECG in the 3rd ICS in accordance with recently established electrocardiographic criteria is unknown. METHODS AND RESULTS: ECGs were recorded in both the 4th and 3rd ICS in 17 Brugada-type ECG patients (group A) and in 206 consecutive male subjects (group B). Brugada-type ECGs were divided into 3 types. In group A, the prevalence of type 1 ECG, which is a coved-type ECG with ST-segment elevation of >/=2 mm, increased from 23.5% to 64.7% when ECG was recorded in the 3rd ICS. The conversion to type 1 ECG was found to be related to induction of ventricular arrhythmia. In group B, the prevalence of Brugada-type ECG increased from 1.5% to 5.8% when the ECG was recorded in the 3rd ICS. CONCLUSIONS: Recording the ECG in the 3rd ICS is useful for identifying high-risk patients with Brugada-type ECG and for detecting concealed Brugada-type ECG.  相似文献   
997.
The plasma and adrenal renin-angiotensin system in stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto (WKY) rats were examined in animals at 5, 11, 18, and 25 weeks of age. Plasma active renin was significantly increased in 18- and 25-week-old SHRSP with impaired renal function, whereas there was no difference in the plasma prorenin level or renal renin content between the two strains at all ages examined. Thus, the rate of activation of prorenin seems to be enhanced in the kidney of SHRSP with malignant hypertension. Adrenal renin contents were severalfold higher in SHRSP than WKY rats at all ages. However, adrenal angiotensin peptides were not increased in SHRSP aged 5 and 11 weeks. In 18-week-old SHRSP, adrenal angiotensin II (Ang II) and III (Ang III) levels were fourfold and 1.8-fold higher, respectively, than in WKY rats, accompanied by 1.5-fold higher plasma aldosterone. Increased adrenal angiotensin and plasma aldosterone were also found in 25-week-old SHRSP. Zonal distribution studies indicated that the elevated Ang II and III in SHRSP were derived mainly from the capsular tissue (the zona glomerulosa). To examine the contribution of circulating angiotensin to the adrenal angiotensin content, effects of bilateral nephrectomy on adrenal angiotensin and renin were examined in 18-week-old rats. At 24 hours after nephrectomy, plasma angiotensin, prorenin, and active renin were decreased to almost negligible concentrations. Conversely, in both adrenal capsular and decapsular tissues of SHRSP and WKY rats, neither angiotensin nor renin was significantly decreased after nephrectomy. These results suggest that the increase in adrenal capsular Ang II contents in SHRSP may be partly due to an enhanced local production of Ang II.  相似文献   
998.
BACKGROUND: There are few reports regarding the concordance of coronary arterial response between acetylcholine (ACh) and ergonovine (ER) spasm provocation tests. OBJECTIVES: We attempted to perform selective spasm provocation tests to examine the incidence of provoked spasm in patients who had undergone first coronary angiography as much as possible and we compared the coronary arterial response and clinical usefulness between selective intracoronary injection of ACh and intracoronary administration of ER. METHODS: We performed 1508 selective spasm provocation tests, consisting of 873 ACh tests and 635 ER tests, from 1991 to 2002. We examined the frequency of provoked spasms of each agent retrospectively. ACh was injected in incremental doses of 20, 50 and 80 microg into the right coronary artery and 20, 50 and 100 microg into the left coronary artery. ER was administered as 10 microg/min over 4 min for a maximal dose of 40 microg in the right coronary artery and as 16 microg/min over 4 min for a total dose of 64 microg in the left coronary artery. Coronary spasm was defined as transient >99% luminal narrowing. RESULTS: Intracoronary ACh provoked spasms in 36.0% of patients and intracoronary ER induced spasms in 29.8% of patients. In patients with ischemic heart disease, the incidence of provoked spasms was not different between ACh tests (50.9%) and ER tests (43.8%). In contrast, the frequency of provoked spasms with ACh tests was significantly higher than that with ER tests (11.0% compared with 6.4%, P<0.05) in patients without ischemic heart disease. Moreover, ACh provoked more spasms in patients without fixed stenosis than ER (36.2% compared with 25.5%, P<0.01) and multiple spasms were frequently observed when performing ACh tests (40.0% compared with 27.0%, P<0.01). Major complications were observed in 1.4% of patients with ACh tests and in 0.2% of patients with ER tests. The need for intracoronary administration of isosorbide dinitrate to relieve coronary spasms during ER testing before performing another coronary artery test was more frequently observed in ACh tests (5.04% compared with 1.49%, P<0.01). However, no serious irreversible complications, such as death or acute myocardial infarction, were observed in this study. There was a significant difference in sex, history of smoking and hyperlipidemia between patients with and without spasms for both tests, whereas no difference in age or hypertension was observed in either test. CONCLUSION: Thus, both selective ACh and ER tests were useful as spasm provocation tests.  相似文献   
999.
A case of solitary neurofibroma in the retroperitoneum involving the uncinate process of the pancreas, which has been reported in only one case in Japan and less than 20 cases in the world literature, is described. A 57-year-old male complained of back pain and microhematuria. Plain and enhanced abdominal computed tomography (CT) indicated an 8 × 6 cm hypovasular tumor located in the uncinate process. We initially assumed it to be a cancer of the pancreas. His physical examination and blood chemistry result were normal. Various diagnostic imaging methods however, disclosed a rare type of tumor. The tumor was resected by pancreaticoduodenectomy and histological examination revealed it to be neurofibroma.  相似文献   
1000.
BACKGROUND: Heart failure consists of two phenotypes: systolic heart failure and diastolic heart failure (DHF). A growing body of evidence demonstrated benefits of beta-blocker, angiotensin-converting enzyme inhibitor, and angiotensin II receptor blocker in systolic heart failure; however, evidence leading to therapeutic strategy of DHF is lacking. METHODS AND RESULTS: The Japanese Diastolic Heart Failure Study (J-DHF) is a multicenter, prospective, randomized trial designed to assess effects of beta-blocker in patients with DHF. A total of 800 patients (400 patients in each group) will be enrolled. The primary outcome is a composite of cardiovascular death and unplanned admission to hospital for congestive heart failure. Other outcomes include all-cause mortality, worsening of the symptoms of heart failure, or a need for modification of the treatment for heart failure. Serial assessment of echocardiographic and neurohumoral parameters and cost analysis of the treatment regimen will be conducted. The follow-up period is a minimum of 2 years. CONCLUSION: This study will provide important evidences for the treatment of DHF.  相似文献   
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