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71.
Paclitaxel and irinotecan are important new anticancer agents. The combination of these two agents has been considered for use against a variety of advanced solid tumors. Since the schedule-dependent effects of this combination may be crucial to its use, we studied the interaction of paclitaxel and SN-38 (the active metabolite of irinotecan) in various schedules in four human cancer cell lines in culture. Cell growth inhibition after 5 days was determined using an MTT assay. The effects of drug combinations at the IC80 level were analyzed by the isobologram method. Simultaneous exposure to paclitaxel and SN-38 for 24 h produced antagonistic (subadditive and protective) effects in the human lung cancer cell line A549, the breast cancer cell line MCF7, and the colon cancer cell line WiDr, and produced additive effects in the ovarian cancer cell line PA1. Sequential exposure to paclitaxel for 24 h followed by SN-38 for 24 h, and the reverse sequence, produced additive effects in all four cell lines. These findings suggest that sequential administration, not simultaneous administration, may be the appropriate schedule for the therapeutic combination of paclitaxel and irinotecan. Continued preclinical and clinical studies should provide further insights and assist in determining the optimal schedule for this combination in clinical use. Received: 25 February 1997 / Accepted: 6 November 1997  相似文献   
72.
To determine whether bucolome (5-n-butyl-1-cyclohexyl-2,4,6-trioxoperhydropyrimidine), a nonsteroidal anti-inflammatory agent, can reverse diuretic resistance of furosemide in patients with nephrotic syndrome, we examined the inhibitory effect of bucolome on the protein binding of furosemide in serum and urine. Bucolome significantly inhibited the protein binding of furosemide not only in serum but also in urine of preparation albumin (UPA), which mimics urinary albumin concentration in patients with nephrotic syndrome by ultrafiltration method. The binding percentage of furosemide to albumin was approximately 70% in UPA. With coadministration of bucolome to healthy volunteers, renal clearance of furosemide was increased, reflecting the increase of the free fraction of furosemide in serum. Furthermore, coadministration of bucolome caused a significant increase of urine volume and sodium concentration in urine. Even at higher urine levels of furosemide, the inhibitory effect of bucolome on the protein binding of furosemide in UPA remains constant, and changes in pH at weakly acidic pH levels (pH 5.5-6.5) did not alter the inhibitory effect of bucolome. Interestingly, coadministration of bucolome with furosemide in doxorubicin (Adriamycin)-induced nephrotic syndrome model rats alleviated the diuretic resistance. These results suggest that bucolome has a potent inhibitory effect on the protein binding of furosemide in the urine and can partially restore the diuretic response of furosemide in patients with nephrotic syndrome by increasing the free fraction of furosemide at the site of action.  相似文献   
73.
Leiomyosarcoma of the scrotum is a rare tumor. Up to 1999, only 29 cases have been reported in the literature worldwide. A 27-year-old man presented with a mass on the left side of the scrotum which had been painless and had gradually enlarged over the previous 10 years. During the following 3 months, however, it became painful and he was then referred to our hospital. Physical examination revealed a solid mass on the left side of the scrotum, measuring 7 cm in diameter, which was not adhering to the testis or to the vas deferens. The tumor was surgically resected. The histological examination confirmed the diagnosis of well differentiated leiomyosarcoma. Adjuvant therapy was considered unnecessary. The follow-up at 41 months revealed no local recurrence or distant metastasis.  相似文献   
74.
NO-1886降低脂负荷新西兰兔血清甘油三酯和游离脂肪酸   总被引:1,自引:0,他引:1  
目的观察NO1886(ibrolipim)对脂肪餐后血脂水平的影响。方法将25只♂新西兰兔随机分为5组正常对照组、脂负荷组、脂负荷+NO1886(05g·kg-1)组、脂负荷+NO1886(10g·kg-1)组、脂负荷+NO1886(15g·kg-1)组;分别在给予20%脂肪乳和相应剂量NO1886前后第1、2、4、6、8、24h从兔耳缘静脉采血,离心收集血清,测定血清甘油三酯和游离脂肪酸。结果NO1886能有效地降低脂负荷后新西兰兔血清甘油三酯和游离脂肪酸水平,呈剂量依赖性,并能使游离脂肪酸恢复到正常。结论NO1886具有调节脂肪餐后血脂水平的作用。  相似文献   
75.
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   
76.
目的 合成化合物NO 1886 ,一种脂蛋白脂酶活化观察脂蛋白脂酶活化剂是否降低高脂 /高蔗糖饲料诱发的糖尿病新西兰兔的血浆葡萄糖并减轻其动脉粥样硬化。方法 给予高脂 /高蔗糖饲料升高新西兰兔血浆总胆固醇 ,甘油三酯和葡萄糖及降低高密度脂蛋白胆固醇而导致动脉粥样硬化。饲料中加入 1 0 %NO 1886进行治疗观察。分别在 0、4、8、12、16、2 0及 2 4wk从禁食过夜的兔耳静脉抽取血样测定葡萄糖和脂质水平。第 2 4周末 ,处死动物 ,分离主动脉 ,经苏丹Ⅳ染色固定脂质后 ,计算脂纹病变面积。结果 应用NO 1886后 ,实验动物血浆葡萄糖 ,总胆固醇和甘油三酯降低 ,高密度脂蛋白胆固醇增加。对动脉粥样硬化的发展具有抑制作用。结论 NO 1886不仅可改善脂质紊乱 ,而且可降低血浆葡萄糖 ,减轻糖尿病兔动脉粥样硬化  相似文献   
77.
Nafamostat mesilate (NM), a clinically used serine protease inhibitor, suppressed the overproduction of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS) in RAW264.7 murine macrophages treated with lipopolysaccharide (LPS, 100 ng/ml); however, it had little effect on endothelial NOS (eNOS) in human umbilical vein endothelial cells (HUVEC). Electrophoretic mobility shift assay (EMSA) revealed that LPS activated nuclear factor-kappaB (NF-kappaB) in RAW264.7 cells and that this activation was suppressed by nafamostat mesilate. Western blotting showed that nafamostat mesilate suppressed the phosphorylation and degradation of inhibitor kappaB-alpha (IkappaB-alpha), which holds NF-kappaB in the cytoplasm in an inactivated state. Our observations suggest that nafamostat mesilate is a candidate agent for various diseases such as ischemia-reperfusion, graft rejection, inflammatory diseases, and autoimmune diseases, in which iNOS and/or NF-kappaB are upregulated.  相似文献   
78.
In rats, an injection of streptozotocin (STZ) elevated blood levels of glucose 4 weeks later (STZ-induced diabetes) and an over-production of microvessels of retinal and choroidal capillaries of eyes developed. A previous study has shown that administration of Stephania tetrandra S. Moore (STSM) in culture prevented the over-production of microvessels of those capillaries of STZ-induced diabetes in vitro. Therefore, the study investigated whether or not orally administered STSM could inhibit over-production of microvessels of those capillaries of STZ injected rats in vivo. When STSM was given at the same time as the STZ injection and continued daily for 7 weeks, STSM prevented the elevation of blood glucose level and over-production of microvessels of those capillaries. When STSM was given after elevation of blood glucose level of glucose (4 weeks after STZ injection) and continued daily for 4 weeks, STSM lowered the elevated blood glucose level but had no effect on the over-production of microvessels of those capillaries. It was inferred that deposition of N(epsilon)(carboxymethyl) lysine in retinal and choroidal tissues, which is induced by STZ-induced diabetes may deteriorate the blood-retinal barrier and the blood-choroidal barrier. One might, therefore, speculate that advanced STZ-induced diabetes may deteriorate the blood-retinal barrier and blood-choroidal barrier. Therefore, STSM may not reach the retinal and choroidal tissues in the posterior ocular region in vivo.  相似文献   
79.
The purpose of this study was to determine the outcomes and optimal practice patterns of definitive radiotherapy for primary vaginal cancer. Between 1993 and 2012, 49 patients were treated with definitive radiotherapy for primary vaginal cancer in three hospitals. Of these, 15 patients (31%) had clinically positive regional lymph node metastasis. A total of 34 patients (70%) received external beam radiotherapy with high-dose-rate brachytherapy (interstitial or intracavitary), and 8 (16%) (with small superficial Stage I tumors) were treated with local radiotherapy. The median follow-up was 33 months (range: 1–169 months). The 3-year overall survival (OS), disease-free survival (DFS), and loco-regional control (LRC) rates were 83%, 59% and 71%, respectively. In multivariate analysis, the histological type (P = 0.044) was significant risk factors for LRC. In Federation of Gynecology and Obstetrics (FIGO) Stage I cases, 3 of 8 patients (38%) who did not undergo prophylactic lymph node irradiation had lymph node recurrence, compared with 2 of 12 patients (17%) who underwent prophylactic pelvic irradiation. For Stage III–IV tumors, the local recurrence rate was 50% and the lymph node recurrence rate was 40%. Patients with FIGO Stage I/II or clinical Stage N1 had a higher recurrence rate with treatment using a single modality compared with the recurrence rate using combined modalities. In conclusion, our treatment outcomes for vaginal cancer were acceptable, but external beam radiotherapy with brachytherapy (interstitial or intracavitary) was needed regardless of FIGO stage. Improvement of treatment outcomes in cases of FIGO Stage III or IV remains a significant challenge.  相似文献   
80.
An 89-year-old woman underwent examinations for leg edema. Blood tests indicated low nutrition and low pancreatic enzymes, and a stool examination indicated fatty stool. Computed tomography showed pleural effusion, ascites, and cystic lesions in the pancreatic head and mural nodules within the cysts. Pancreatic juice cytology revealed adenocarcinoma. The diagnosis was pancreatic exocrine insufficiency caused by intraductal papillary mucinous carcinoma. The patient did not wish to undergo surgery. Therefore, diuretics, component nutrients, and pancreatic exocrine replacement therapy using pancrelipase were initiated. After starting treatment, her leg edema, pleural effusion, and ascites disappeared, and her activities of daily living improved markedly.  相似文献   
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