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101.
Y Kinoshita  C Kawanami  K Kishi  H Nakata  Y Seino    T Chiba 《Gut》1997,41(4):452-458
Background—Gastric acid secretion in Japanesesubjects decreases with aging. One of the possible causative mechanismsof this attenuated acid secretion is speculated to be aHelicobacter pylori induced chronic gastritis. Theinfection rate of this microorganism has decreased recently in Japan.
Aims—To investigate whether gastric acidsecretion has altered over the past 20 years, and if so, what theinfluence of H pylori infection might be in the Japanese population.
Subjects and methods—Gastric acid secretion, serumgastrin and pepsinogen I and II concentrations, and Hpylori infection were determined in 110 Japanese subjects inboth the 1970s and 1990s.
Results—Basal acid output as well as maximal acidoutput have greatly increased over the past 20 years, not only inindividuals with H pylori infection but also in thosewithout infection. Furthermore, subjects with H pyloriinfection tended to show decreased gastric acid secretion in comparisonwith those without infection, particularly in geriatric subjects. Therewas a positive correlation between gastric acid secretion and serumpepsinogen I concentrations.
Conclusions—In Japan, both basal andstimulated gastric acid secretion have increased over the past 20 years; some unknown factors other than the decrease in Hpylori infection may play an important role in this phenomenon.

Keywords:gastric acid; Helicobacter pylori; aging; gastrin

  相似文献   
102.

Purpose

Thiamine is an essential component of glucose metabolism and energy production. The disulfide derivative, thiamine tetrahydrofurfuryl disulfide (TTFD), is better absorbed than readily-available water-soluble thiamine salts because it does not require the rate-limiting transport system required for thiamine absorption. However, the detailed pharmacokinetics of thiamine and TTFD under normal and pathological conditions have not yet been clarified. C-11-labeled thiamine and TTFD were recently synthesized by our group. In this study, to clarify the differences in pharmacokinetics and metabolism of these probes, a quantitative PET imaging study and radiometabolite analysis of C-11-labeled thiamine and TTFD were performed in the rat heart.

Procedures

Positron emission tomography (PET) imaging with [11C]thiamine and [11C]TTFD was performed in normal rats to determine the pharmacokinetics of these probes, and the radiometabolites of both probes from the blood and heart tissue were analyzed by thin-layer chromatography.

Results

Accumulation of [11C]TTFD was significantly higher than that of [11C]thiamine in the rat heart. Moreover, as a result of the radiometabolite analysis of heart tissue at 15 min after the injection of [11C]TTFD, thiamine pyrophosphate, which serves as a cofactor for the enzymes involved in glucose metabolism, was found as the major radiometabolite and at a significantly higher level than in the [11C]thiamine-injected group.

Conclusions

PET imaging techniques for visualizing the kinetics and metabolism of thiamine using [11C]thiamine and [11C]TTFD were developed in this study. Consequently, noninvasive PET imaging for the pathophysiology of thiamine-related cardiac function may provide novel information about heart failure and related disorders.
  相似文献   
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We report a rare case of pulmonary lymphomatoid granulomatosis radiologically mimicking interstitial pneumonia. A 57-year-old man was admitted to our hospital because of chest bilateral reticular shadow with sustained cough and breathlessness for 10 years. Chest CT scans showed multiple ground-glass opacities, traction bronchiectasis and cystic change in both lungs, in addition to hilar and mediastinal lymphadenopathy. A histopathologically diagnosis of pulmonary lymphomatoid granulomatosis (angiocentric immunoproliferative lesion, grade 1) was made by thoracoscopic lung biopsy. In this case, serological and immunohistochemical analyses did not show Epstein-Barr virus infection. No clinical or radiological deterioration has been observed thereafter despite no medication.  相似文献   
107.
Background We have reported that percutaneous radiofrequency ablation (RFA) with balloon occlusion of the hepatic artery (balloon-occluded RFA), using an expandable electrode, increases the coagulation area. In this study, we investigated the efficacy of balloon-occluded RFA and balloon-microcatheter-occluded RFA, using a cool RF single electrode.Methods We studies 41 patients with 47 hepatocellular carcinoma (HCC) lesions. We treated 28 patients (32 nodules) with balloon-occluded RFA, 5 patients (6 nodules) with balloon-microcatheter-occluded RFA, and 8 patients (9 nodules) with standard RFA. Initial therapeutic efficacy was evaluated with dynamic computed tomography performed 1 week after one session of treatment.Results One session of treatment was done for 20 nodules (62.5%) in the balloon-occluded RFA group and for 4 nodules (66.7%) in the balloon-microcatheter-occluded RFA group. We compared the coagulation diameter for balloon-occluded RFA (7 nodules), balloon-microcatheter-occluded RFA (6 nodules), and standard RFA (9 nodules) after one application cycle (12min). The greatest dimension of the area coagulated by balloon-occluded RFA was significantly larger (greatest long-axis dimension, 47.6 ± 7.8mm; greatest short-axis dimension, 33.4 ± 7.5mm) than that coagulated by standard RFA (greatest long-axis dimension, 35.3 ± 4.7mm; greatest short-axis dimension, 25.9 ± 3.7mm; P = 0.002 for greatest long-axis dimension; P = 0.041 for greatest short-axis dimension). However, there was significant difference only in the greatest short-axis dimension of the area coagulated comparing balloon-microcatheter-occluded RFA and standard RFA.Conclusions We consider balloon-occluded RFA using a cool RF electrode to be superior to standard RFA for the treatment of HCC, especially when larger coagulation volumes are required.  相似文献   
108.
To determine the characteristic radiologic findings of inflammatory pseudotumor of the liver, various imagings of ten patients (11 lesions) with proven diagnoses of inflammatory pseudotumor were reviewed. Radiologic examinations, i.e., computed tomography (CT; 11 lesions), ultrasonography (11 lesions), magnetic resonance imaging (MRI; 6 lesions), angiography (10 lesions), CT during arterio-portography (CTAP; 3 lesions), and gallium-67 scans (9 lesions) were analyzed for their utility in diagnosis. No inflammatory pseudotumor showed a fibrous capsule around the lesion. Ten of the 11 lesions were poorly demarcated on most of the imagings, and all 11 lesions showed delayed and/or prolonged enhancement on CT or MRI. Arterio-portal shunting was observed in 4 lesions after contrast material administration on CT or angiography. Central lesions with suspiciously high fibrotic tissue content were demonstrated in 5 lesions on CT or MRI. Major vessels coursing in the lesions were demonstrated in 4 lesions by CT, MRI, and CTAP. Inflammatory pseudotumor of the liver should be included in the differential diagnosis in patients with hepatic masses, even if the patients are asymptomatic. If radiologic examinations suggest inflammatory pseudotumor, percutaneous biopsies should be performed so that unnecessary surgery can be avoided.  相似文献   
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OBJECTIVE: To study the epidemiologic manifestations of a large outbreak of Legionnaires' disease due to an inadequate circulating and filtration system for bath water. PATIENTS: In June 2000 at Ishioka City, Ibaraki Prefecture, a large outbreak of Legionnaire's disease occurred, as a result of an inadequate circulating and filtration system for communal bath water. This outbreak was the worst ever experienced in Japan, involving a total of 34 patients (20 confirmed, 14 probable), 3 of whom died. MEASUREMENTS AND RESULTS: Legionella pneumophila serogroup 1 was isolated from sputum culture in two patients. Bacteriological culture of the public bath water subsequently yielded large numbers of Legionella species. Cleavage of genomic DNA showed that restriction fragment patterns coming from clinical and environmental isolates of L. pneumophila serogroup 1 were closely related, focusing the inquiry to a public bathhouse where a circulating filtration system was suspected as the source of infection. CONCLUSIONS: It was later concluded that the circulating filtration system adopted for bath water was marred by a serious design flaw that subsequently caused the mass outbreak. Specifically, a line of the bath water was being returned to the bath without undergoing heat exchange or sterilization by chlorine; and the Legionella species that had proliferated in the filter and the bright stone filtration unit were allowed to return to the bath, eventually culminating in a mass infection.  相似文献   
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