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51.
Long-term toluene abuse causes a variety of psychiatric symptoms. However, little is known about abnormalities at the neurochemical level in the living human brain after long-term exposure to toluene. To detect neurochemical changes in the basal ganglia of subjects with a history of long-term toluene use, proton magnetic resonance spectroscopy (1H MRS) was performed in 12 abstinent toluene users and 13 healthy comparisons with no history of drug abuse. N-acetylaspartate (NAA), creatine plus phosphocreatine (Cr + PCr), choline-containing compounds (Cho), and myo-inositol (MI) levels were measured in the left and right basal ganglia. The Cho/Cr + PCr ratio, a marker of membrane metabolism, was significantly increased in the basal ganglia of toluene users in comparison to that of the control subjects. Furthermore, the increase in the Cho/Cr + PCr ratio was significantly correlated with the severity of residual psychiatric symptoms. These findings suggest that long-term toluene use causes membrane disturbance in the basal ganglia, which is associated with residual psychiatric symptoms that persist even after long-term abstinence from toluene use.  相似文献   
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Cholecystokinin 2 (CCK2) receptors have been implicated as mediators of anxiety in standard mouse models such as exploratory behavior both in black and white test boxes and in elevated plus-mazes. We investigated the role of the CCK2 receptor in anxiety by evaluating the behavior of mice lacking the gene for this receptor in these standard anxiety models (i.e., exploratory behavior in a black and white test box and exploratory behavior in an elevated plus-maze). In the black and white test box, mice lacking the CCK2 receptor gene showed significantly increased numbers of transitions between the boxes compared to control mice. In the elevated plus-maze, mice lacking the CCK2 receptor gene displayed significantly more head dips than control mice. These results suggest that mice lacking the CCK2 receptor gene are less anxious than normal mice.  相似文献   
53.
We examined metabolism of PbTxs in New Zealand cockle, Austrovenus (A.) stutchburyi, and greenshell mussel, Perna (P.) canaliculus, by means of liquid chromatography coupled with tandem mass spectrometry. PbTx-2, PbTx-3 and BTX-B5 were detected in Karenia (K.) brevis culture medium in the ratio of ca. 50:2:5. The amounts of PbTx-3 and BTX-B5 were greatly increased in both seawater and shellfish exposed to K. brevis cultures or supernatant prepared by disruption of K. brevis under appropriate condition, while those of PbTx-2 were decreased. Some PbTx-2 was present in P. canaliculus, but not in A. stutchburyi. Low levels of BTX-B1 were detected in A. stutchburyi, but not P. canaliculus. Levels of PbTx-3 and BTX-B5 were highest immediately after exposure and then declined rapidly in both shellfish. BTX-B1 increased in concentration after exposure, and was then gradually eliminated from A. stutchburyi. Three successive exposures of A. stutchburyi to K. brevis cultures resulted in similar initial levels of PbTx-3 and BTX-B5, while BTX-B1 accumulated after each dose. In P. canaliculus, initial levels of PbTx-3 were similar, while PbTx-2 and BTX-B5 accumulated after each dose. PbTx-3 and BTX-B5 are proposed to be suitable markers for monitoring shellfish toxicity after a red tide event.  相似文献   
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BACKGROUND: Although the anti-atherosclerotic effects of HMG-CoA reductase inhibitors are well known, their specific effect on saphenous vein grafts after coronary artery bypass graft (CABG) operation is not well documented and has not been studied in Japan, so the aim of the present prospective randomized controlled study involving 27 Japanese institutions was to investigate the effects of pravastatin on the progression of atherosclerosis in such grafts and native coronary arteries after CABG. METHODS AND RESULTS: A total of 303 patients who had undergone CABG were randomly assigned to either the pravastatin group (n =168) or the control group (n = 167). Paired coronary angiograms were obtained at baseline and at the end of 5-year follow-up in 182 (60%) patients. The low-density lipoprotein cholesterol concentration significantly decreased in the pravastatin group from 141.4 mg/dl to 113.7 mg/dl (-19.6%), compared with 141.1 mg/dl to 133.7 mg/dl (-5.2%) in the control group (p < 0.001). Although there was no significant difference in the quantitative coronary angiography measurements between the 2 groups, the global change score indicated a significant pravastatin-mediated reduction in plaque progression (p < 0.01). CONCLUSIONS: Pravastatin can potentially reduce atherosclerotic progression in both the bypass graft and native coronary arteries of patients after CABG.  相似文献   
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ABSTRACT— Hepatic venograms made in 40 authentic cases of idiopathic portal hypertension (Banti's syndrome) were compared with 13 normal venograms and venograms obtained in 88 cases of cirrhosis, and analyzed in the light of the pathological changes seen in 16 postmortem liver specimens. There were frequent anastomoses between hepatic vein radicles, approximation of middle-size branches to the liver surface, reduction in the angles between the main hepatic vein and its tributaries, and difficulty in opacifying portal vein branches in wedged retrograde portography. These angiographic alterations were corroborated by gross pathological findings which comprised displacement of middle-size hepatic vein branches closer to the liver surface and their approximation among themselves, and seem to be accounted for by the disappearance of liver parenchyma secondary to the peripheral portal circulatory failure.  相似文献   
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Background The impact of isolated diastolic dysfunction (IDD) and systolic dysfunction (SD) on health-related quality of life (HRQOL) is unknown. Methods and Results To evaluate HRQOL in patients with IDD and SD under treatment, information on outpatients aged 60-84 years was extracted from the records of 4,500 consecutive individuals who underwent echocardiographic examination at Sado General Hospital. The medical records of these patients were reviewed and a questionnaire, including the Medical Outcome Study Short Form 36, was mailed to 71 IDD and 99 SD patients; answers were obtained from 66 and 91 patients, respectively. The HRQOL of patients with cardiac dysfunction was impaired even when echocardiographic parameters improved with treatment. Patients with IDD showed an impairment of HRQOL similar to those with SD. Compared with males, female patients had a larger and more significant reduction in the physical and mental components of the HRQOL score. These scores correlated positively with exercise capacity in patients with IDD or SD. Conclusions Impaired HRQOL, in both its mental and physical components, is a serious problem for IDD and SD patients under treatment. Because exercise intolerance may underlie the reduced HRQOL, improving exercise capacity could be an important target for managing outpatients with heart failure. (Circ J 2008; 72: 1436 - 1442).  相似文献   
60.
We investigated 32 patients with bacteremia that occurred in the Department of Urology, School of Medicine, Kanazawa University between April, 1983 and March, 1989. This incidence represented 1.9% of the total number of inpatients. The study group comprised 29 males and 3 females, and their age varied from 25 to 82 years with a mean age of 61.7 years. Twenty-two (75%) of the 32 patients had urologic malignancies. The majority of patients were compromised hosts who had one or more (average, 3.8) factors that promoted bacteremia. Urinary tract infections existed in 26 (86.0%) patients before the bacteremic episode and urine cultures revealed a species identical to that simultaneously isolated from the blood in 19 (73.1%) of the 26 patients. Out of the 26 patients, there were 22 (84.6%) with complicated pyelonephritis and 22 (84.6%) with an indwelling urinary tract catheter. In blood cultures, the most common isolate was Staphylococcus epidermidis and gram-positive cocci were cultured at a rate of 43.9% which was higher than that (39.0%) of gram-negative rods. In contrast, in urine cultures, gram-negative rods were isolated predominantly. S. epidermidis and Corynebacterium spp. isolated less frequently in blood than in urine, indicated contaminants. However, Enterococcus spp. and Candida albicans were recognized as causative organisms of bacteremia via the urinary tract, because the urine culture demonstrated a species identical to that obtained from blood in these bacteremic patients. Antibiotic sensitivity tests demonstrated that isolates from blood tended to show tolerance to beta-lactam antibiotics, but had good sensitivity to aminoglycosides.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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