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71.
用光化学沟通方法确证了从葡萄科植物蘡薁Vitis thunbergii(Vitaceae)中分离得到的( )-cis-ε-viniferin的结构;并纠正了文献核磁共振氢谱(^1H-NMR)数据。  相似文献   
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PURPOSE: To evaluate the optimal management strategy during clinical remission and after relapse in patients with non-Hodgkin's lymphoma (NHL). METHODS: Sixty-six patients with relapse of NHL from a state of clinical remission between 1987 and 1997 were analyzed retrospectively. The pattern of relapses, diagnostic methods used for relapses, and clinical outcome of salvage treatment were analyzed with attention to time after the achievement of clinical remission. RESULTS: Thirty-three relapses (50%) occurred within 12 months, and the remainder occurred gradually from 12-48 months after the first remission. Diagnosis of relapse in 61 of the 66 patients (93%) was made at unscheduled evaluations prompted by symptoms, on physical examinations, or because of high LDH levels. The 1- and 5-year cause-specific survival rates after relapse were 56.7% and 39.4%, respectively. The 1- and 5-year relapse-free survival rates were 50.1% and 35.0%, respectively. The 5-year relapse-free survival rate in patients with late relapse (49.5%) was significantly better than in those with early relapse (21.2%) (p<0.01). CONCLUSION: Time to relapse may be a useful factor to determine optimal management strategy in NHL patients.  相似文献   
73.
BACKGROUND: The efficacy of inactivated influenza vaccine in healthy infants and children younger than 24 months has not been confirmed. The aim of the present study was to determine the prophylactic effect of inactivated influenza vaccine against influenza A in healthy children aged 6-24 months. METHODS: Healthy infants and young children (6-24 months old) were immunized by subcutaneous injection of inactivated influenza vaccine before influenza seasons. Age matched children were randomly assigned as the control. These children were followed up from January to April in each year (2000, 2001 and 2002). The attack rates of influenza A infection was compared and statistically assessed. RESULTS: The attack rate of influenza A virus infection in the vaccine group and the control group were 14.8% (n = 27) vs 12.5% (n = 32) in 2000 (P = 0.526); 2.8% (n = 72) vs 7.2% (n = 69) in 2001 (P = 0.203); and 3.4% (n = 52) vs 8.9% (n = 56) in 2002 (P = 0.205). The attack rates of influenza A between the two groups were not significantly different. CONCLUSIONS: Inactivated influenza vaccine did not reduce the attack rate of influenza A infection in 6-24 month old children.  相似文献   
74.
目的:合成天然产物taxinine NN-3和taxinine NN-14,研究其对肿瘤细胞的多药耐药逆转活性.方法:以紫杉宁为出发原料,通过选择性水解9,10位的乙酰氧基,制成原乙酸酯后再水解.结果:以紫杉宁为原料经过3步反应,可以同时获得taxinine NN-3,taxinine NN-4两种天然产物,其中taxinine NN-3的收率为25%,taxinineNN-4的收率为68%.结论:高收率地合成了taxinine NN-3和taxinine NN-14.  相似文献   
75.
Primary intrapulmonary thymomas are defined as primary thymomas arising in an intrapulmonary location without an associated mediastinal component, and they are very rare. A total of 20 cases have been reported only sporadically in the English literature since 1951. We reported the case of 41-year-old woman who had a 3.5 x 3.0 x 3.0 cm lower right lobe mass with nodal metastasis that extended over the left atrium. We also summarized the clinicopathological features of a total of 21 cases and discussed the problems involved with diagnosis, pathogenesis and treatment. Knowledge of the biological behavior of primary intrapulmonary thymomas is limited because of their rarity. In particular, the issue of the need for lymph node dissection has not been adequately discussed. In this case, pathohistological examination revealed that the routes of lymphatic spread and the sites of noda metastases from primary intrapulmonary thymoma resemble those of primary lung cancer. Therefore, systematic mediastinal lymph node dissection according to the lymph node map for primary lung cancer should be recommended for malignant cases.  相似文献   
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We examined the sequential histopathological changes in the placenta from rats exposed to cisplatin. Cisplatin was intraperitoneally administered at 2 mg/kg/day during GDs 11–12 (GD11,12-treated group), or GDs 13–14 (GD13,14-treated group), and the placentas were sampled on GDs 13, 15, 17 and 21. Fetal mortality rates were increased up to approximately 65% from GD 17 onward, and fetal weights were decreased on GD 21 in the GD11,12-treated group. A reduction in placental weights was detected from GD 15 onward, and the placentas on GD 21 were macroscopically small and thin in both treated groups. Histopathologically, in the GD13,14-treated group, an increase in apoptotic cells was detected on GDs 15 and 17 in the labyrinth zone, and on GD 21 in the basal zone, resulting in labyrinth zone hypoplasia. By contrast, in the GD11,12-treated group, an increase in apoptotic cells was detected on GDs 13, 15 and 17 in the labyrinth zone, and during the experimental period in the basal zone. A decrease in Phospho-Histone H3 positive cells was detected on GD 13 in the labyrinth zone and basal zone, resulting in hypoplasia of the labyrinth zone and basal zone. In addition, a marked decrease in glycogen cell-islands in the basal zone was also detected on GDs 15 and 17. There was a reduction in interstitial invasion of glycogen cell-like trophoblasts into the metrial gland on GD 15, resulting in metrial gland hypoplasia. Therefore, we consider that cisplatin administration in pregnant rats induces growth arrest of the labyrinth zone and basal zone, leading to small placenta. It is assumed that metrial gland hypoplasia is secondarily induced by the failure of glycogen cell island development associated with basal zone hypoplasia.  相似文献   
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