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101.
Aiming at the development of anticancer agents by modification of phenolic benzo[c]phenanthridine alkaloid, additional hydroxyl group was put on C10 position of fagaridine (1) by a biomimetic synthetic procedure to afford 10-hydroxyfagaridine (12). All of the synthetic intermediates were also screenedin vitro antitumor activities against five different cell lines as well as12. Among them the representative cytotoxic results are shown as follows;p-quinone (11) [ED50 (A549=0.22 μg/ml), (HCT15=0.21 μg/ml), fagaridine (1) (HCT 15=0.41 μg/ml), olefin (6) (HCT 15=0.06 μg/ml), acetal (7) (SKMEL-2=0.07 μg/ml), dihydrofagaridne (10) (A549=0. 38 μg/ml), 10-hydroxyfagaridine (12) (A 549=0.45 μg/ml). From these observation three main remarks can be drawn; (i) the iminium part of benzo[c]phenanthridine is not essential for showing acitvities, (ii) the additional hydroxyl group did not contribute to enhance the cytotoxicity, (iii) the 3-arylisoquinolin-1(2H)-one derivatives were found to display significantin vitro antitumor activity.  相似文献   
102.
Kang Y  Harris LJ 《Laterality》1996,1(4):269-279
College students' reports of their parents' handedness were compared with data provided by the parents themselves. The students' reports of their parents' writing hand were highly accurate, the reports of their parents' general handedness somewhat less so. For the latter measure, the students were asked, 'What is your mother's (father's) handedness?' and were given the choice 'left','either', 'right',and 'don't know'. Their answers were then compared with the investigators' classification based on the parents' answers to a 10-item hand-use questionnaire. For this measure, the accuracy of the students' reports was also found to be related to the students' own handedness.  相似文献   
103.
We reported serial neuroradiological findings of a 20-year-old male with subacute sclerosing panencephalitis, who deteriorated from Jabbour stage 2 to stage 4 rapidly in spite of oral administration of inosine pranobex. At the stage 2, brain magnetic resonance imaging (MRI), computed tomography (CT) and [99mTc]-L, L-ethyl cysteinate dimer (99mTc-ECD) single photon emission computed tomography(SPECT) findings were normal. As the disease progressed, brain MRI and CT revealed diffuse cerebral white matter lesions as well as cerebral atrophy. 99mTc-ECD SPECT showed serially various perfusion of cerebrum. These findings in 99mTc-ECD SPECT may reflect the acute inflammatory process and consequent destruction of brain tissue.  相似文献   
104.
目的 探讨胃肠术后 1号治疗急性弥漫性腹膜炎的疗效。方法 测定 2 0例急性弥漫性腹膜炎患者 (随机分为 2组 :对照组 10例 ,治疗组 10例 )血中乳酸、DAO水平。结果 急性弥漫性腹膜炎患者血中乳酸、DAO呈现不同程度升高 ,经治疗随病情好转 ,血中乳酸、DAO呈现不同程度下降 ,而治疗组血中乳酸、DAO下降幅度显著 ,优于对照组 (P <0 .0 5 )。结论 血中乳酸、DAO在急性弥漫性腹膜炎患者病理过程中起重要作用 ,可作为评估急性弥漫性腹膜炎患者严重程度的指标 ,胃肠术后 1号使乳酸、DAO水平下降 ,促进疾病恢复  相似文献   
105.
BACKGROUND: Dendritic cells are potent antigen-presenting cells that bind allogeneic T cells. They are thus candidates for targeting immunoregulatory molecules to the alloreactive T cell compartment and suppressing the alloimmune response. METHOD: A dendritic cell line derived from the BALB/c mouse (H2d) was genetically modified to express the immunoregulatory molecule CTLA4-Ig. The ability of these dendritic cell transfectants to downregulate the alloimmune response was tested in an islet transplant model. Allogeneic C57Bl/6 (H2b) mice were rendered diabetic with streptozocin, and they received BALB/c islet (H2d) transplants. Mice were administered 25 million untransfected or CTLA4-Ig-transfected D2SC/1 cells i.v. on the day of islet transplantation and 6 days later[fnc]. RESULT: Mice treated with CTLA4-Ig-transfected D2SC/1 cells demonstrated prolonged allograft survival (mean = 20 days, median = 17 days, SD = 9.39) compared with mice treated with untransfected D2SC/1 cells (mean = 12 days, median = 11 days, SD=2.74) or untreated control mice (mean = 11 days, median = 11 days SD = 1.41). Third party allograft survival was not prolonged in mice receiving similar treatment. CONCLUSIONS: These results demonstrate that a genetically modified dendritic cell line can suppress the alloimmune response and prolong islet allograft survival in an allospecific manner. The findings also suggest that genetically modified dendritic cells may be useful in targeting alloreactive T cells and prolonging allograft survival.  相似文献   
106.
BACKGROUND: Capecitabine (Xeloda) is a novel, oral, selectively tumor-activated fluoropyrimidine with proven activity in the treatment of advanced colorectal cancer. This trial was conducted to evaluate the efficacy, safety and feasibility of capecitabine in previously untreated patients with advanced and/or metastatic gastric cancer, with a view to replacing 5-fluorouracil (5-FU) in such patients. PATIENTS AND METHODS: Forty-four patients received capecitabine 1250 mg/m2 twice daily (2500 mg/m2/day) for 14 days followed by 7 days of rest, for up to six cycles. RESULTS: Capecitabine produced an objective response rate of 34% (all partial responses) and stable disease in 14 patients (30%). The median time to disease progression (TTP) was 3.2 months [95% confidence interval (CI) 2.7-6.4 months] and median overall survival was 9.5 months (95% CI 6.9-13.2 months). Hand-foot syndrome (HFS), nausea, anorexia, diarrhea and vomiting were the most common adverse events. While HFS was the most frequent grade 3/4 toxicity (National Cancer Institute Common Toxicity Criteria), only 9% of patients experienced grade 3 HFS. Severe myelosuppression was not reported during the study. CONCLUSIONS: Capecitabine monotherapy is active and well tolerated as first-line therapy in patients with advanced/metastatic gastric cancer. Larger comparative trials investigating capecitabine-based combination regimens in patients with advanced gastric cancer are warranted.  相似文献   
107.
The distribution of smooth muscle fibers in the extrahepatic bile duct (EBD) wall is not well characterized. We analyzed 101 consecutive Whipple's operation specimens and 21 autopsy specimens for the pattern of smooth muscle distribution in EBD using the Masson-trichrome stain and the desmin immunohistochemical stain. The patterns were categorized as continuous, interrupted, scattered, and no muscle layer. EBDs were divided into lower, middle, and upper portions, and the distribution pattern of smooth muscle fibers was analyzed separately in each portion. Because most surgically resected specimens contained the middle and lower EBDs with only a portion of the upper EBD, only the length of the middle and lower EBDs (common bile duct, CBD) was measured. The mean length of CBD in surgically resected specimens was 6.4 +/- 1.4 cm (men, 6.6 +/- 1.3 cm; women, 6.1 +/- 1.5 cm). The mean length of CBD in autopsy specimens was 6.8 +/- 1.0 cm. The predominant patterns of the lower third of the EBD were interrupted (49%) and continuous (43%). The predominant patterns of the middle third of the EBD were scattered (63%) and interrupted (23%). Those of the upper third of the EBD were no muscle fiber (58%) and scattered (39%). In conclusion, different patterns of smooth muscle distribution were observed in different portions of the EBD. Because scattered muscle fibers or no muscle fibers were the main features of the upper third of the EBD, understanding of this pattern may be helpful for assessment of the depth of invasion or staging of carcinoma of the upper third of the EBD.  相似文献   
108.
Peroxiredoxins in breast carcinoma.   总被引:11,自引:0,他引:11  
PURPOSE: Peroxiredoxins (Prxs) are a novel group of peroxidases containing high antioxidant efficiency and some of them having also effects on cell differentiation and apoptosis. The mammalian Prx family has six distinct members located in various subcellular locations, including peroxisomes and mitochondria, places where oxidative stress is most evident. EXPERIMENTAL DESIGN: We examined immunohistochemically a large set of samples from patients with breast carcinoma and investigated associations with parameters such as tumor-node-metastasis classification, hormone receptor status, and patient survival. Three biopsies of healthy breast tissue were used as controls. RESULTS: Expression of peroxiredoxins I, III, IV, and V was found in >or=80% of cases, whereas the expression of Prx II and VI was less frequent. Increased expression of Prx III was found to associate with the presence of progesterone (P = 0.02) and estrogen (P = 0.03) receptors, and Prxs IV (P = 0.009) and VI (P = 0.04) were overexpressed in progesterone receptor positive cases. Prx V was the only isoform that associated with items of tumor-node-metastasis classification, it was connected to a larger tumor size (P = 0.05) and positive lymph node status (P = 0.04). Prx V positivity was also connected with shorter survival (P = 0.04), whereas Prxs III (P = 0.002) and IV (P = 0.02) were related to better prognosis, probably resulting from their connection with a positive hormone receptor status. CONCLUSIONS: In conclusion, we found that expression of peroxiredoxins, especially III, IV and V, is increased in breast malignancy, suggesting the induction of Prxs as response to increased production of reactive oxygen species in carcinomatous tissue.  相似文献   
109.
目的 探讨高同型半胱氨酸 (HCY)血症引起心血管病和出生性缺陷的作用机制。方法 采用诱导筛选方法克隆高同型半胱氨酸诱导基因 HCY- 2 ,以 Northern印迹分析检测 HCY- 2基因在大鼠不同组织中的表达 ,以免疫组化方法验证 HCY- 2蛋白在大鼠不同组织中的表达。结果 以诱导筛选方法从大鼠血管平滑肌细胞内克隆到一个新的全长 c DNA,即高同型半胱氨酸诱导基因 HCY- 2 ,它编码 142个氨基酸。Northern印迹分析和免疫组化检测表明 ,HCY- 2基因可在大鼠心、肾、脑、肝、肺等组织中广泛表达。在体外 ,将重组 HCY- 2基因转移至内皮细胞中 ,能够引起细胞凋亡和 DNA损伤 ;在体内 ,将 HCY- 2基因转移至鸡胚内 ,则诱发鸡胚细胞凋亡 ,并引起畸形。结论  HCY- 2基因可能是一种新的凋亡基因 ,高同型半胱氨酸血症可能通过 HCY- 2基因诱发心血管病和出生性畸形。  相似文献   
110.
Objective: To study the pattern of lymphnode metastasis in carcinoma of esophagus. Methods: 200 cases of resected esophageal cancer specimens were carefully examined pathologically. Lymphnode metastasis, its pathway and extent in relation to pathological changes were analyzed. Results: Lymphnode metastasis was mainly regional and extended vertically in both directions. Leaping-over metastasis was another feature. The deeper invasion by the tumor, the higher frequencies of metastasis development, and vice versa. However, leaping-over metastasis was more likely to occur where tumor invasion was less severe. Conclusion: Owing to the high frequency of lymphnode metastasis in the superior mediastinum and the widely spanned leaping-over metastasis, an operative approach by three incisions through right thoracotomy with excision of the whole segment of esophagus and anastomosis at cervical region was recommended, in order to dissect lymphnodes in the cervical, thoracic and abdominal regions and to leave less or no metastatic lymphnodes behind.  相似文献   
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