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101.
m-Dinitrobenzene intoxication due to skin absorption 总被引:1,自引:0,他引:1
Nobuo Ishihara Akira Kanaya Masayuki Ikeda 《International archives of occupational and environmental health》1976,36(3):161-168
Summary A case of m-dinitrobenzene intoxication is described. Clinical picture of the patient who was exposed to an industrial material containing m-dinitrobenzene, methaemoglobinemia and excretion of urinary metabolites observed in a volunteer who experimentally worked with the same material, absence of m-dinitrobenzene in the ambient air during the exposure, and penetration of m-dinitrobenzene through the protective gloves which were used by the patient indicate that m-dinitrobenzene was the toxic agent and that the main route of the invasion was skin absorption. 相似文献
102.
Kato M Imamura M Hosotani R Shimada Y Doi R Itami A Komoto I KosakaM T T Konishi J 《World journal of surgery》2000,24(11):1425-1430
The intravenous secretin injection test (secretin test) has been used for the differential diagnosis of gastrinoma. In this
study we report that the intraoperative secretin test (IOS test) is also useful for determining the extent of curability in
patients with Zollinger-Ellison syndrome (ZES). Twelve patients with ZES underwent surgical exploration and the IOS test.
The results of the IOS test were obtained by rapid radioimmunoassay of the serum gastrin level (IRG) within 60 minutes. The
test was diagnosed as negative when the maximum increase of serum IRG was less than 80 pg/ml and also less than 20% of the
basal serum IRG level. Three of the twelve patients underwent pancreatoduodenectomy (PD), and two patients underwent distal
pancreatectomy. Extirpation of duodenal tumors with dissection of regional lymph nodes was performed in seven patients. In
two of the seven patients the IOS test remained positive after extirpation of the duodenal tumors and the dissection of regional
lymph nodes. In one patient PD was performed on the basis of the positive results, and the IOS test became negative after
PD. In the other patient, two tiny metastatic liver tumors were identified and were resected, but the IOS test did not become
negative. We closed the abdomen in 11 patients when we obtained negative results from the IOS test. The results of the IOS
test were almost identical to the data obtained by the standard assay postoperatively. The serum IRG levels of all but one
patient fell to the normal level, and the secretin test became negative postoperatively. The IOS test is thus useful and indispensable
for curative resection of microgastrinomas in patients with ZES. 相似文献
103.
26,26,26,27,27,27-Hexafluoro-1alpha,25(OH)2 vitamin D3, a hexafluorinated analog of 1alpha,25(OH)2 vitamin D3, has been reported to be several times more potent than the parent compound with respect to some vitamin D actions. The reason for enhanced biological activity in the bones, kidneys, and small intestine appears to be related to F6-1alpha,25(OH)2 vitamin D3 metabolism to ST-232 (26,26,26,27,27,27-hexafluoro-1alpha,23S,25-trihydroxyvitamin D3), a bioactive 23S-hydroxylated form that is resistant to further metabolism. We compared the disposition and metabolism of [1beta-3H]F6-1alpha,25(OH)2 vitamin D3 and [1beta-3H]1alpha,25(OH)2 vitamin D3 in parathyroid glands of rats intravenously administered with labeled compounds at a dose of 10 microg/kg. In the [1beta-3H]F6-1alpha,25(OH)2 vitamin D3-dosed group, radioactivity was highly detected in the kidneys, parathyroid glands, and the small intestine. The radioactivity in the parathyroid glands remained high until 48 h postdosing, with values of 2.5, 8.4, and 14.6 times higher at 6, 24, and 48 h postdosing than after dosing with [1beta-3H] 1alpha,25(OH)2 vitamin D3. In the group given [1beta-3H]F6-1alpha,25(OH)2 vitamin D3, the unchanged compound was mainly detected with a small amount of ST-232 at 6 h postdosing. At the 24- and 48-h time points, over half of the radioactivity was observed as ST-232, and additionally, ST-233, the 23-oxo form, accounted for a small amount at the 48-h time point. The present study demonstrated local retention of [1beta-3H]F6-1alpha,25(OH)2 vitamin D3 and the bioactive metabolite ST-232 in parathyroid glands after intravenous administration. The findings may indicate one of the reasons for the higher potency of F6-1alpha,25(OH)2 vitamin D3 than 1alpha,25(OH)2 vitamin D3 in parathyroid. 相似文献
104.
Takeyuki Yatsu Masanao Sanagi Akira Fujimori Yuichi Tomura Kazumi Hayashi Masayuki Tanahashi Osamu Inagaki 《Pharmacological research》2003,47(3):243-252
Several factors such as proteinuria and renal fibrosis may be important in the progression of many forms of chronic renal diseases. The purposes of the current study were to investigate the progressive renal failure of the rats with surgical renal mass reduction (RMR) and the effect of the angiotensin-converting enzyme (ACE) inhibitor, lisinopril, and to document correlation of several factors associated with progressive renal failure. Rats were subtotal (5/6) nephrectomized by resection of the renal poles and sham-operated. The functional, histological and haematological changes of the rats were studied for up to 10 weeks. After 2 weeks of RMR, oral administration of lisinopril (10 mg kg(-1) per day) was performed for 8 weeks. RMR resulted in progressive renal failure with proteinuria, monocyte/macrophage (ED1+) infiltration, anaemia as assessed by haemoglobin and haematocrit (Htc), renal hypertrophy as assessed by left kidney to body weight ratio (BKW/BW), and renal fibrosis as assessed by glomerular lesions and tubulointerstitial changes. Lisinopril exhibited renoprotection with antiproteinuric effect and inhibition of monocyte/macrophage (ED1+) infiltration. However, beneficial effect of lisinopril on anaemia was not observed. At 10 weeks after surgery, severity of proteinuria positively correlated with plasma creatinine (Pcr), BKW/BW, histological damage, and systolic blood pressure, and negatively correlated with haemoglobin. Severity of tubulointerstitial changes positively correlated with Pcr and blood urea nitrogen, and negatively correlated with haemoglobin and Htc. Moreover, monocyte/macrophage (ED1+) infiltration positively correlated with severity of proteinuria and tubulointerstitial changes. These findings strongly support that proteinuria, monocyte/macrophage infiltration and renal fibrosis appear to play principal roles in the progressive renal failure with anaemia and renoprotection of ACE inhibition may be mediated by multiple actions of ACE inhibitor. The present study confirms that rats with RMR is useful to explore target molecules for renoprotective drugs and evaluate renoprotective effect of new molecular entities. 相似文献
105.
Loss of expression of DNA repair enzymes MGMT,hMLH1, and hMSH2 during tumor progression in gastric cancer 总被引:11,自引:0,他引:11
Yoshihiko Kitajima Kohji Miyazaki Shiroh Matsukura Masayuki Tanaka Mutsuo Sekiguchi 《Gastric cancer》2003,6(2):86-95
BACKGROUND: Disorders of the DNA repair system that protects against alkylating mutagens are known to play an important role in carcinogenesis. METHODS: We investigated the expression of the DNA repair enzyme that protects against alkylating mutagens, O(6)-methylguanine DNA methyltransferase (MGMT), and the mismatch repair (MMR) enzymes, hMLH1 and hMSH2, in 135 gastric cancer specimens by immunohistochemical means. RESULTS: The immunoreactivity of MGMT and MMR proteins correlated significantly with several clinicopathologic factors. The survival curve in 116 patients showed that a loss of MGMT or hMLH1, but not of hMSH2, correlated with a poor prognosis. Combined evaluation of MGMT and hMLH1 revealed that the survival of patients with negative status for both MGMT and hMLH1 was shortest. However, this significant association between patient survival and MGMT or hMLH1 expression disappeared when early and advanced cancers were separately analyzed, indicating that synchronous losses of MGMT and hMLH1 increase during tumor progression and stage. Further evaluation according to histologic type revealed that loss of MGMT, hMLH1, and hMSH2 expression significantly differed between early and advanced cancer in differentiated-type cancers. In contrast, in undifferentiated-type cancer, loss of MGMT and MMR expression was frequently found even in intramucosal (m) cancer, and no significant difference was found in loss of hMLH1 and hMSH2 between early and advanced cancer. CONCLUSION: These findings demonstrate that the reduced expression of MGMT, hMLH1, and hMSH2 in differentiated-type cancer may play an important role during tumor progression between the early and advanced stage. On the other hand, in undifferentiated-type cancer, loss of MGMT and the MMR proteins appears to be an important event at carcinogenesis or at an earlier step of tumor progression. 相似文献
106.
Hideaki Suzuki Akira Shimomura Katsuhisa Ikeda Masayuki Furukawa Takeshi Oshima Tomonori Takasaka 《The Laryngoscope》1997,107(12):1661-1666
The mechanism of macrolide therapy in chronic sinusitis patients is unclear. The authors studied the effect of macrolides on interleukin (IL)-8 secretion from cultured human nasal epithelial cells. Epithelial cells harvested from the nasal polyps of patients with chronic sinusitis were primary-cultured, and secreted IL-8 in culture media was measured by enzyme immunoassay. The cells secreted considerable amounts of IL-8 constitutively and in response to lipopolysaccharide. The secretion was significantly inhibited by 10?5 M of erythromycin, clarithromycin, roxithromycin, and josamycin. 10?6 M erythromycin still showed the inhibitory effect, whereas the same concentration of josamycin did not. These results indicate that macrolide antibiotics may act as an immunomodulator to reduce IL-8 in inflammatory sites and, at least partially, account for the clinically discrepant effects between 14- and 16-membered ring macrolides in long-term low-dose therapy for chronic sinusitis. 相似文献
107.
108.
为了检测妇女绝经后发生骨量减少的相关指标进而倡导依据生活方式的特点对绝经后妇女骨质疏松的发生采取相应的预防和护理方针,我们对日本乡村的绝经后妇女(末次月经后六个月或更长时间算起)进行了为期4a的随访。我们运用双能X线骨密度仪(DXA)对腰椎骨密度(BMD)进行检测并对各种变量,包括年龄、绝经时的年龄、骨折史、日常摄奶量以及吸烟习惯进行多元分析,结果表明这些因素对于腰椎骨密度(BMD)的恢复是不相关联的。
在这些变量中,骨折史被证明对于相关人群是最具危险性的,这些对象有高比例的骨量减少(6.6%),其次是不规律的摄奶(13.6%)和吸烟(9.3%)。在护理中使用的作用于足跟骨的检测骨密度的设备被证实与作用于腰椎的DXA设备可以相互替代。依据这些结果,针对居住在日本乡村的绝经后妇女制订了相应的预防骨质疏松的方针。这些卫生指导方针依据特定区域的生活方式而制定并可适用于其他的人群和区域。在本文中,作者列出了不同的有助于预防绝经后妇女出现骨质疏松的方法并进行了调查。 相似文献
109.
Tetsuya Mitsudomi Takayuki Kosaka Hideki Endoh Yoshitsugu Horio Toyoaki Hida Shoichi Mori Shunzo Hatooka Masayuki Shinoda Takashi Takahashi Yasushi Yatabe 《Journal of clinical oncology》2005,23(11):2513-2520
PURPOSE: To evaluate the relationship between mutations of the epidermal growth factor receptor (EGFR) gene and the effectiveness of gefitinib treatment in patients with recurrent lung cancer after pulmonary resection. PATIENTS AND METHODS: We sequenced exons 18-21 of the EGFR gene using total RNA extracted from 59 patients with lung cancer who were treated with gefitinib for recurrent lung cancer. Gefitinib effectiveness was evaluated by both imaging studies and change in serum carcinoembryonic antigen (CEA) levels. RESULTS: EGFR mutations were found in 33 patients (56%). Of these mutations, 17 were deletions around codons 746-750 and 15 were point mutations (12 at codon 858, three at other codons), and one was an insertion. EGFR mutations were significantly more prevalent in females, adenocarcinoma, and never-smokers. Gefitinib treatment resulted in tumor shrinkage and/or CEA decrease to less than half of the baseline level in 26 patients, tumor growth and/or CEA elevation in 24 patients, and gefitinib effect was not assessable in nine patients. Female, never-smoking patients with adenocarcinoma tended to respond better to gefitinib treatment. Gefitinib was effective in 24 of 29 patients with EGFR mutations, compared with two of 21 patients without mutations (P < .0001). Of note, del746-750 might be superior to L858R mutations for prediction of gefitinib response. Patients with EGFR mutations survived for a longer period than those without the mutations after initiation of gefitinib treatment (P = .0053). CONCLUSION: EGFR mutations were a good predictor of clinical benefit of gefitinib in this setting. 相似文献
110.