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991.
Gotaro Masuda Akira Tokunaga Takashi Shirakawa Akiyoshi Togashi Teruo Kiyama Shunji Kato Norio Matsukura Hideki Bou Masanori Watanabe Takashi Tajiri 《Gastric cancer》2007,10(2):98-103
Background Gastric cancers in young adults are thought to be associated with risk factors that include Helicobacter pylori infection and genetic polymorphism. The objective of this study was to elucidate the roles of these risk factors in patients
younger than 40 years by analyzing clinicopathological data and H. pylori infection, and using molecular epidemiologic techniques.
Methods Clinicopathological features, the presence of H. pylori infection, endoscopic characteristics of gastritis, genetic polymorphism of P4502E1 (CYP2E1), and family history of cancer
in patients with gastric cancer treated surgically at Nippon Medical School Hospital from 1991 to 2004 were analyzed, based
on our medical database.
Results Gastric cancer in those younger than 40 years was characterized by a predominance of female patients with poorly differentiated
adenocarcinoma who had undergone total gastrectomy with extended lymphadenectomy. H. pylori infection had a higher prevalence in patients with gastric cancer than in patients with normal endoscopic results or chronic
gastritis, especially in those younger than 40 years (odds ratio, 13.7). Atrophic gastritis, nodular gastritis, and rugal
hyperplastic gastritis were observed by endoscopy as H. pylori-associated gastritis. No difference in the incidence of either CYP2E1 genetic polymorphism or a family history of cancer was
observed among different age groups.
Conclusion Gastric cancer in patients younger than 40 years is closely associated with H. pylori infection, but not with genetic characteristics. Eradication therapy for H. pylori and endoscopic examination of H. pylori-positive young adults may be anticipated to be adopted as a strategy for the prevention and/or early detection of cancer. 相似文献
992.
T Hidaka K Kato R Yonezawa T Shima A Nakashima K Nagira T Nakamura S Saito 《European journal of surgical oncology》2007,33(1):86-90
AIM: The objective of this study is to ascertain whether omission of lymphadenectomy is possible when endometrial cancer is considered low-risk based on intraoperative pathologic indicators. PATIENT AND METHODS: A total of 128 patients were deemed to be low-risk based on intraoperative evaluation, including frozen-section determination of grade and myometrial invasion. We divided these 128 patients into 2 groups, the total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH-BSO) with lymphadenectomy (LA group, n=68) and the TAH-BSO without lymphadenectomy (non-LA group, n=60) group. The only adjuvant treatment used was chemotherapy, and the decision to use chemotherapy was based on stage, grade, or lymphovascular space involvement. A retrospective review of the medical records was performed, and disease-free survival (DFS), overall survival (OS), operative time, estimated blood loss during operation, percentage of transfusion requirement, incidence of post-operative leg lymphedema and post-operative deep vein thrombosis were evaluated. RESULTS: The 5-year DFS and OS rates were 95.6% and 98.5% in the LA group, and 98.3% and 98.3% in the non-LA group, respectively, and were not significantly different. In the LA group, pelvic lymph node metastasis was observed in only 1 case. In the LA group, blood loss during operation, percentage of transfusion requirement and the incidence of post-operative leg lymphedema were significantly higher than those in the non-LA group. CONCLUSION: Lymphadenectomy did not provide a significant survival advantage in the patients with low-risk corpus cancer. Additionally, some peri- and post-operative morbidities and complications were increased by the addition of lymphadenectomy. The present findings suggest that lymphadenectomy should be limited for low-risk corpus cancer. 相似文献
993.
994.
Kazumi Komoriya Yukio Kato Yujiro Hayashi Kazuhiro Ohsuye Ryuichiro Nishigaki Yuichi Sugiyama 《Drug metabolism and disposition》2007,35(3):469-475
Lanoteplase is a recombinant mutant of tissue-type plasminogen activator (t-PA) that was developed with an aim to overcome the drawback of rapid systemic elimination of t-PA. In this study, we examined the disposition profile of lanoteplase in vivo and the kinetics of receptor-mediated endocytosis (RME) of this recombinant t-PA in vitro to kinetically characterize the mechanism(s) underlying its tissue distribution and elimination. Integration plot analysis of the initial-phase tissue distribution in rats revealed a much lower uptake clearance (CL(uptake)) of lanoteplase in the liver than that of t-PA. Rate constants for cell surface binding, internalization, and degradation of lanoteplase were also lower than those for t-PA in primary cultured rat hepatocytes. These results suggest that the improved stability of lanoteplase in vivo could be accounted for by the delay in the RME of this recombinant protein. The CL(uptake) in the liver decreased with coadministration of lactoferrin, a ligand for the low-density lipoprotein receptor-related protein (LRP) and the asialoglycoprotein (ASGP) receptors in normal mice, and in lrpap1((-/-)) mice, which have a hereditary deficiency of LRP; In contrast, CL(uptake) was not affected by mannose, whereas that of t-PA decreased with both ligands and in the lrpap1((-/-)) mice. Thus, the hepatic disposition of lanoteplase seems to be mediated by common specific receptors for t-PA, including LRP and the ASGP receptors, whereas the mannose receptor seems to be only minimally involved in the disposition of lanoteplase. 相似文献
995.
Toxicogenomics of drug-induced hemolytic anemia by analyzing gene expression profiles in the spleen.
996.
Yukiko Naito Kazumi Tago Tomoko Nagata Mami Furuya Takayuki Seki Hiroyasu Kato Tomomi Morimura Naoki Ohara 《Food and chemical toxicology》2007,45(9):1575-1587
A 90-day ad libitum administration toxicity study of oligoglucosamine (OG) was carried out using F344 rats of both sexes. The animals were divided into four groups of 20 animals each, 10 of each sex, and fed a diet containing 0, 0.04, 0.2 or 1.0 (w/w)% OG. During the administration period, no animals of either sex died or exhibited abnormal signs in the 0.04% OG and 0.2% OG groups. In the 1% OG group, in both sexes, erythema and swelling of the snout and forelimbs and loss of fur in the forelimbs were observed. On macroscopic observation, emaciation, swelling of the snout, auricles and forelimbs and alopecia of the forelimbs were also observed in 2-3 males of the 1% OG group. It was suggested that these topical abnormalities might be due to dermal responses to OG adhering to the skin and fur, which are easily soiled with saliva during grooming. In the animals of the 1% OG group, food consumption decreased, resulting in body weight gain being suppressed. This was found concomitantly with the abnormal findings mentioned above. Thus, feeding difficulties due to the topical lesions on the snout and forelimbs were thought to affect body weight. In hematology, platelet count, lymphocyte count and differential neutrophil count increased in males of the 1% OG group. These changes might be related to the dermal inflammation. Abnormalities in urinalysis and blood chemistry, as well as a small thymus, small spleen, dark spots or areas on the glandular stomach mucosa, pale Harderian glands and small testes in histopathology, were also observed in males in the 1% OG group. Whether or not all these changes were related only to the malnutrition remains to be elucidated. From these results, OG gave rise to no adverse effects in rats up to the dose level of 0.2 (w/w)%. Thus, the no observed adverse effect level was determined to be 0.2 (w/w)% for rats of either sex (124.0mg/kg/day in males, 142.0mg/kg/day in females). 相似文献
997.
目的分析破裂动脉瘤的大小、形态及瘤体长与瘤颈宽之比。方法对61个破裂动脉瘤的三维CT脑血管造影图像进行分析,测量动脉瘤的最大径,计算瘤体长与瘤颈宽之比,分析其形态特征,观察有无小泡样凸起和分叶状改变。结果动脉瘤的最大径平均为8.54 mm;78.8%的动脉瘤最大径<10 mm。动脉瘤的瘤体长与瘤颈宽之比平均为2.15;65%的动脉瘤其瘤体长与瘤颈宽之比>1.6。45.9%的动脉瘤有小泡样凸起或呈分叶状改变。结论最大径<10 mm的动脉瘤同样可能破裂;60%以上的破裂动脉瘤其瘤体长与瘤颈宽之比>1.6;小泡样凸起和分叶状改变在破裂动脉瘤中比较多见。 相似文献
998.
Combination chemotherapy with cisplatin and irinotecan in patients with adenocarcinoma of the small intestine 总被引:1,自引:0,他引:1
Makiko Ono Kuniaki Shirao Atsuo Takashima Chigusa Morizane Natsuko Okita Daisuke Takahari Yoshinori Hirashima Takako Eguchi-Nakajima Ken Kato Tetsuya Hamaguchi Yasuhide Yamada Yasuhiro Shimada 《Gastric cancer》2008,11(4):201-205
Background Small-bowel adenocarcinoma (SBA) is a rare tumor that has a poor response to chemotherapy and a poor prognosis. Treatment
strategies for SBA have not been clearly established.
Methods All patients with SBA treated using a combination of cisplatin and irinotecan (IP) as first-line chemotherapy at the National
Cancer Center Hospital in Japan between January 1999 and February 2007 were studied retrospectively.
Results Eight patients received IP as first-line chemotherapy. The median follow-up was 9.5 months (range, 4.2–37.5 months). The median
number of cycles of IP was three (range, 1–5). The overall response rate (complete or partial response) was 12.5% (complete
response, n = 0; partial response, n = 1). The disease control rate (complete or partial response or stable disease) was 75%. The median time to treatment failure
was 4.5 months (95% confidence interval, 0.9–5.8 months), and overall survival was 17.3 months (range, 1.9–21.3 months). The
most common adverse events were neutropenia and anorexia.
Conclusion IP combination chemotherapy may be an acceptable option for patients with SBA. Further studies are warranted to determine
the optimal chemotherapeutic regimen for SBA. 相似文献
999.
Takayoshi Kiba Takashi Inamoto Tsutomu Nishimura Masaya Ueno Kazuhiro Yanagihara Satoshi Teramukai Hironori Kato Masakazu Toi Masanori Fukushima 《BMC cancer》2008,8(1):323
Backgrounds
Prognostic factors are defined as biological or clinical measurement associated with overall survival and/or disease-free survival. Previous studies have shown that patients with estrogen receptor (ER) positive cancers have a better prognosis than patients whose cancers do not have these receptors. 相似文献1000.
Effects of sleep deprivation on neural cardiovascular control may have important clinical implications. We tested the hypothesis that sleep deprivation increases heart rate, blood pressure, and sympathetic activity and potentiates their responses to stressful stimuli. We studied 8 healthy subjects (aged 40+/-5 years, 6 men and 2 women). Blood pressure, heart rate, forearm vascular resistance, and muscle sympathetic nerve activity were measured at rest and during 4 stressors (sustained handgrip, maximal forearm ischemia, mental stress, and cold pressor test). Measurements were obtained twice, once after normal sleep and once after a night of sleep deprivation. All measurements were obtained in a blinded, randomized manner. In comparison with normal sleep, sleep deprivation resulted in an increase in blood pressure (normal sleep versus sleep deprivation=82+/-8 versus 86+/-7 mm Hg, mean+/-SEM, P=0.012) and a decrease in muscle sympathetic nerve activity (normal sleep versus sleep deprivation=28+/-6 versus 22+/-6 bursts/min, P=0.017). Heart rate, forearm vascular resistance, and plasma catecholamines were not significantly changed by sleep deprivation, nor did sleep deprivation affect autonomic and hemodynamic responses to stressful stimuli. Sleep deprivation results in increased resting blood pressure, decreased muscle sympathetic nerve activity, and no change in heart rate. Thus, the pressor response to sleep deprivation is not mediated by muscle sympathetic vasoconstriction or tachycardia. 相似文献