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71.
张方  黄泰康 《中草药》2003,34(12):1058-1062
对目前中药药效的研究方法进行全面论述,找出存在问题,并对中药药效方法学进行初步探讨。提出中医学发展是中药药效方法学研究的基础和前提,尤其是藏象经络学说和中药的归经理论的现代研究的突破对中药药效方法学研究起着主导作用;中药药效方法学研究四维系统论,在药效作用物质基础和药物作用机制两维的基础上增加时间维和人体精神维。  相似文献   
72.
目的:建立傣药雅路哈(接骨1号)中槲皮素的含量测定方法。方法:采用高效液相色谱法,C18色谱柱(4.6mm×200mm,5μm);流动相:甲醇-0.4%磷酸溶液(52∶48);检测波长:360nm;流速:1.0mL/min;柱温:30℃。结果:槲皮素在10.56~528μg范围内线性关系良好(r=0.9999),回收率98.21%,RSD为l.87%。结论:为傣药雅路哈(接骨1号)质量标准的研究,提供准确、可靠的方法。  相似文献   
73.
肝内胆管癌30例的临床病理特征及预后分析   总被引:1,自引:0,他引:1  
目的 :探讨肝内胆管癌 (intra hepaticcholangiocarcinoma ,ICC)的临床病理特征及治疗与预后的关系。方法 :回顾性分析 1991~ 1999年山东省立医院、济宁医学院附属医院 3 0例ICC患者病理、临床资料。结果 :ICC比肝细胞癌少见且预后不良 ,手术切除是目前较理想治疗方式 ,影响预后的因素是肿瘤边缘、淋巴结转移与组织病理情况。根治切除术后 1年生存率 5 3 3 % ,3年生存率 3 3 3 %。结论 :根治性切除是最有效的治疗方法。  相似文献   
74.
A23187为一种钙离子载体(calcium ionophore,CI),可提高胞浆内游离钙水平,模拟某些细胞内信号转导事件,导致多基因活化[1-2].我们先前曾探讨了A23187对正常人外周血单核细胞(peripheral monotytes,PBMC)来源的DC的影响[3],最近,我们进行了有关A23187诱导MMe患者的PBMC向DC分化的实验研究.  相似文献   
75.
PURPOSE: To prospectively compare standard radiation therapy (RT) with an abbreviated course of RT in older patients with glioblastoma multiforme (GBM). PATIENTS AND METHODS: One hundred patients with GBM, age 60 years or older, were randomly assigned after surgery to receive either standard RT (60 Gy in 30 fractions over 6 weeks) or a shorter course of RT (40 Gy in 15 fractions over 3 weeks). The primary end point was overall survival. The secondary end points were proportionate survival at 6 months, health-related quality of life (HRQoL), and corticosteroid requirement. HRQoL was assessed using the Karnofsky performance status (KPS) and Functional Assessment of Cancer Therapy-Brain (FACT-Br). RESULTS: All patients had died at the time of analysis. Overall survival times measured from randomization were similar at 5.1 months for standard RT versus 5.6 months for the shorter course (log-rank test, P =.57). The survival probabilities at 6 months were also similar at 44.7% for standard RT versus 41.7% for the shorter course (lower-bound 95% CI, -13.7). KPS scores varied markedly but were not significantly different between the two groups (Wilcoxon test, P =.63). Low completion rates of the FACT-Br (45%) precluded meaningful comparisons between the two groups. Of patients completing RT as planned, 49% of patients (standard RT) versus 23% required an increase in posttreatment corticosteroid dosage (chi(2) test, P =.02). CONCLUSION: There is no difference in survival between patients receiving standard RT or short-course RT. In view of the similar KPS scores, decreased increment in corticosteroid requirement, and reduced treatment time, the abbreviated course of RT seems to be a reasonable treatment option for older patients with GBM.  相似文献   
76.
PURPOSE: Abnormalities of FHIT, a candidate tumor suppressor gene, have frequently been found in multiple malignancies, including head and neck squamous cell carcinoma (HNSCC). To define its role in HNSCC treated with surgery and postoperative radiotherapy (PORT), the Fhit protein expression status was investigated in 80 patients enrolled in a prospective Phase III clinical trial addressing the dose and fractionation regimen of PORT. EXPERIMENTAL DESIGN: Immunohistochemical staining of HNSCC tissue sections for Fhit expression was performed. The Fhit expression status was correlated with the clinicopathological characteristics and clinical course. The median follow-up duration was 4.9 years. RESULTS: Loss of Fhit expression was found in 52 of the 80 study patients (65%). There was not a significant association between Fhit expression and clinical characteristics. Patients whose tumor exhibited negative Fhit expression had a significantly worse 5-year overall survival duration [hazard ratio = 0.49; 95% confidence interval, 0.23-1.03; P = 0.05 (log-rank test)] than did those whose tumor exhibited positive Fhit expression. One third of the patients with a Fhit-negative tumor had distant metastasis during the follow-up period. Paradoxically, patients classified as high risk who had a Fhit-negative tumor experienced locoregional recurrence less often (18%) than did high-risk patients who had a Fhit-positive tumor (33%). CONCLUSIONS: Loss of Fhit expression is a poor prognostic indicator in patients with HNSCC. However, tumors lacking Fhit expression may be more sensitive to PORT and therefore more susceptible to locoregional control.  相似文献   
77.
78.
We report a case of an 80-year-old man with osteoblastic metastases from advanced carcinoma of the prostate presenting with a grand mal seizure resulting from severe hypocalcaemia. He had low serum phosphate and ionised calcium levels, elevated serum skeletal alkaline phosphatase and intact parathormone levels. 99mTc radioisotope bone scan revealed a "super bone scan" suggestive of osteomalacia. The serum 1, 25-dihydroxycholecalciferol level was unexpectedly elevated. The biochemical abnormalities persisted despite high dose calcium replacement, but improved with supraphysiological doses of 1,25 (OH)2 vitamin D3 (Rocaltrol) therapy. We hypothesise that the hypocalcaemia in this patient was due to vitamin D resistance secondary to a humoral factor secreted by the tumour.  相似文献   
79.
Scirrhous gastric cancer is characteristic in that cancer cells proliferate and invade with prominent fibrosis. To search for the expression of specific carbohydrate chains in scirrhous gastric cancer, we have examined the glycosphingolipid composition of scirrhous cancer tissues (n=10) in comparison with that of non-scirrhous cancer tissues (n=10) by means of two-dimensional thin layer chromatography, followed by fast atom bombardment mass spectrometry of the individual glycolipids and immunostaining analysis. The major neutral glycosphingolipids from scirrhous gastric cancer tissues were identified as ceramide monohexoside, ceramide dihexoside, globotriaosyl ceramide (Gb3) and globoside (Gb4), while the major acidic glycosphingolipids were II3 Neu-Acα-LacCer, II3 NeuAcα2-LacCer and sulfatide. Relative concentrations of Gb3 and Gb4 in scirrhous gastric cancer tissues (Gb3+ Gb4=58%) were two times higher than those in non-scirrhous gastric cancer tissues (29%). Orthotopic fibroblasts cloned from scirrhous gastric cancer tissues showed similar high concentrations of Gb3 and Gb4 to scirrhous gastric cancer tissues. Furthermore, immunohistochemical study revealed that Gb3 and Gb4 were expressed intensely on the fibroblasts. On the other hand, analysis of glycosphingolipids in four scirrhous gastric cancer cell lines yielded the following results. i) The contents of Gb3 and Gb4 were low (6%), compared with orthotopic fibroblasts (62%). ii) Significant amounts of Lea (pentaglycosylceramide) and Leb (hexa- and heptaglycosylceramides), which could not be detected in scirrhous cancer tissues, were observed. The results show that the major neutral glycosphingolipids such as Gb3 and Gb4 of scirrhous gastric cancer tissues were derived from orthotopic fibroblasts and not from the cancer cells.  相似文献   
80.
Objectives: Because several serum studies of vitamin D metabolites have produced equivocal results on their relation to prostate cancer risk, the purpose of this study is to evaluate this association further.Methods: A nested case-control study in a cohort of 3,737 Japanese-American men examined from 1967 to 1970 was conducted in Hawaii (United States). At the time of examination, a single blood specimen was obtained, and the serum was frozen. After a surveillance period of over 23 years, 136 tissue-confirmed incident cases of prostate cancer were identified. Their stored sera and those of 136 matched controls were measured for the following: 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, calcium, phosphorus, and parathyroid hormone.Results: There were no notable differences between cases and controls in their median serum levels of the five laboratory measurements. Odds ratios (OR) for prostate cancer, based on the quartiles of serum levels in controls, were also determined. The ORs for the highest quartiles relative to the lowest were 0.8 (95 percent confidence interval [CI] = 0.4-1.8) for 25-hydroxyvitamin D and 1.0 (CI = 0.5-2.1) for 1,25-dihydroxyvitamin D.Conclusion: It is possible that the lack of sufficient numbers of study subjects with low vitamin D levels affected the results. Nonetheless, the findings suggest that there is a lack of a strong association between vitamin D and prostate cancer.  相似文献   
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