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991.
BACKGROUND AND AIM: The attenuated antisecretory activity observed during continuous administration of ranitidine has been described as tolerance. However, it remains unclear whether a similar phenomenon occurs with other histamine H2 receptor antagonists (H2RA). We investigated whether tolerance to famotidine, a stronger H2RA than ranitidine, occurs during long-term administration. METHODS: Seven healthy male Japanese subjects without Helicobacter pylori infection participated in a randomized cross-over study in which ranitidine and famotidine were administered for 14 days with a 4-week wash-out period. We performed 24-h intragastric pH monitoring on the first and 14th days of administration of each drug, and measured serum gastrin and plasma drug concentrations on the first, seventh and 14th days. RESULTS: The acid-inhibiting activity of ranitidine and famotidine declined during continuous administration. In particular, the potent nocturnal pH-increasing effect of the H2RA, which was observed on day 1, declined on day 14. Serum gastrin concentrations on day 14 were significantly lower than those on day 7, although plasma drug concentrations remained unchanged. CONCLUSION: Tolerance to famotidine occurs during continuous administration for 14 days, as previously shown in ranitidine studies.  相似文献   
992.
The authors reviewed the computed tomographic (CT) scans and pathologic specimens of 57 histologically proved bronchogenic carcinomas (35 squamous cell carcinomas, 12 small cell carcinomas, and 10 adenocarcinomas) in 47 patients with diffuse pulmonary fibrosis. The patients ranged in age from 61 to 87 years (mean age, 72 years; 42 men and 5 women). On radiography and CT, most tumors (82%) were located in peripheral areas of honeycomb lung. In 50 of the 57 lesions, the tumors were round or lobulated with sharp margins. In seven tumors, including six squamous cell carcinomas and one small cell carcinoma, the tumor invaded the adjacent honeycomb lung and lacked distinct margins. Intratumor lucency was seen in 13 tumors (five solitary and eight multiple). The CT findings, including high-resolution CT scans, were compared with the histologic findings in a subgroup of 29 lesions in 25 patients with available surgical or autopsy specimens. Invasive growth of tumors with unclear margins (four lesions), septal thickening of the contiguous/surrounding honeycombed areas (16 lesions), and discrete masses (nine lesions) with solitary (four of nine) or multiple (five of nine) intratumor lucencies. The lucencies in six of nine patients (67%) with intratumor lucencies were found to represent engulfed cystic airspaces histologically. CT revealed that bronchogenic carcinoma associated with diffuse pulmonary fibrosis has distinct morphologic characteristics that correlate histologically with a specific pattern of tumor growth.  相似文献   
993.
BACKGROUND/AIMS: Inflammatory cytokines, such as interleukin-1 beta and tumor necrosis factor-alpha, which activate neutrophils, contribute to hepatic warm ischemia-reperfusion injury. However, the role of the cytokines in hepatic microcirculation immediately after reperfusion is still unclear. This study was carried out to investigate whether FR167653, a dual inhibitor of interleukin-1 beta and tumor necrosis factor-alpha, attenuates hepatic microcirculatory disturbance at the initial phase of reperfusion following liver ischemia. METHODOLOGY: Adult mongrel dogs were subjected to 90 minutes of liver ischemia by a Pringle's maneuver under portosystemic bypass. The animals were divided into two groups: a control group (n = 10), subjected to hepatic warm ischemia only, and a FR167653 administered group (n = 5), which received 1 mg/kg/h FR167653 for 4 hours since 30 minutes before the ischemia to 2 hours after the reperfusion continuously. Seven days animal survival, hepatic tissue blood flow, liver function test, hepatic venous blood concentration of endothelin-1 and plasminogen activator inhibitor-1, liver tissue biochemistry, and histopathology were analyzed. RESULTS: The treatment with FR167653 attenuated microcirculatory disturbance, lessened liver injury, enhanced adenine nucleotides resynthesis, and improved animal survival after liver ischemia. In addition, FR167653 significantly inhibited release of both endothelin-1 and plasminogen activator inhibitor-1 from the liver cells. CONCLUSIONS: These results suggest that the inflammatory cytokines induce microcirculatory disturbance in the initial phase of reperfusion following liver ischemia.  相似文献   
994.
995.
996.
This study evaluated the prevalence of obstructive sleep apnea‐related symptoms and assessed the relationship with obesity or unusual sleep postures in Down syndrome patients in Japan. We obtained the demographic characteristics, sleep postures, and obstructive sleep apnea‐related symptoms experienced by 90 people as reported by their caregivers. Although 71% reported snoring and 59% arousals, obstructive sleep apnea‐related symptoms were not significantly different between obese and non‐obese participants. The youngest age group had the fewest obstructive sleep apnea‐related symptoms, especially symptoms of snoring. The odds for arousal, nocturia, and apnea tended to be higher in the unusual sleep‐postures group. Unusual sleep postures were most frequent in the group 6–15 years of age. People with Down syndrome might sleep in unusual postures to avoid upper airway obstruction caused by other anatomical factors. For nurses and other health professionals working in mainstream service, it is important to screen all persons with Down syndrome for symptoms suggestive of obstructive sleep apnea, particularly those six years of age and older, and to refer them for further evaluation for sleep disorders.  相似文献   
997.
Although endoscopic retrograde cholangiopancreatography (ERCP) is an important procedure for the diagnosis and treatment of pancreaticobiliary diseases, post-ERCP pancreatitis (PEP) is the most frequent adverse event that can sometimes be fatal. However, prophylactic pancreatic stent (PS) insertion has been performed to prevent PEP in high-risk patients. In some randomized controlled trials (RCTs) and meta-analyses, the efficacy of prophylactic PS insertion has been shown to prevent PEP. In addition, several types of stents have been used to decrease PEP. In this review, we introduce the details of these RCTs and meta-analyses and reveal the specifications for stent placement, for example, the stent diameter and length and the pancreatic region into which the stent should be inserted.  相似文献   
998.
任卫红  刘玉华  罗银弟 《护理研究》2008,22(19):1744-1745
[目的]探讨多因素强化干预对病程1年内的2型糖尿病(T2DM)病人颈总动脉内中膜厚度增厚影响研究的护理配合情况.[方法]对90例T2DM病人进行调查、随访,评价教育效果,观察教育前后病人服药、检测指标行为正确率和临床代谢指标的比较统计.[结果]90例新诊断T2DM病人教育后病人知识掌握、行为正确率依从性显著改善;教育后多代谢指标比教育前显著减低.[结论]通过护理有效干预,保证了对新发2型糖尿病病人颈总动脉内中膜厚度增厚影响研究顺利进行.  相似文献   
999.
Suzuki M  Miyai I  Ono T  Kubota K 《NeuroImage》2008,39(2):600-607
Neural activities in the primary motor cortex and supplementary motor area increase during the preparation as well as execution of voluntary movements of the hand and foot. However, there are few studies concerning preparatory activities of the brain preceding walking performance. We investigated how a verbal instruction "ready" before walking affected cortical activations and walking performances using a functional near-infrared spectroscopy. Seven healthy subjects performed two locomotor tasks on a treadmill with a verbal instruction "ready" before the treadmill was started (prepared walking; PW) and without it (simple walking; SW). Cadence was smaller and stride length was longer in PW than in SW. Increases of oxygenated hemoglobin (oxyHb) in the frontal regions especially in the prefrontal and premotor cortices were greater in PW than in SW both during the preparation and walking periods. These results suggested that preparation for walking cued by a verbal instruction enhanced frontal activations both during the preparation and execution of walking as well as walking performance.  相似文献   
1000.

Purpose

We aimed to elucidate trans-1-amino-3-[18F]fluorocyclobutanecarboxylic acid (anti-[18F]FACBC) uptake mechanisms in inflammatory and tumor cells, in comparison with those of l-[methyl-11C]methionine ([11C]Met) and 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG).

Procedures

Using carbon-14-labeled tracers, in vitro time-course, pH dependence, and competitive inhibition uptake experiments were performed in rat inflammatory (T cells, B cells, granulocytes, macrophages), prostate cancer (MLLB2), and glioma (C6) cells.

Results

Anti-[14C]FACBC uptake ratios of T/B cells to tumor cells were comparable, while those of granulocytes/macrophages to tumor cells were lower than those for [14C]FDG. Over half of anti-[14C]FACBC uptake by T/B and tumor cells was mediated by Na+-dependent amino acid transporters (system ASC), whereas most [14C]Met transport in all cells was mediated by Na+-independent carriers (system L).

Conclusions

The low anti-[18F]FACBC accumulation in granulocytes/macrophages may be advantageous in discriminating inflamed regions from tumors. The significant anti-[18F]FACBC uptake in T/B cells may cause false-positives in some cancer patients who undergo FACBC-positron emission tomography (PET).  相似文献   
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