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排序方式: 共有299条查询结果,搜索用时 15 毫秒
61.
目的:研究黄花铁线莲Clematis intricata干燥带花枝条中的抗肿瘤活性成分。方法:采用海虾幼虫致死实验为抗肿瘤活性追踪测试模型,硅胶、SephadexLH-20和制备型HPLC等色谱手段进行分离纯化,根据波谱数据结合理化性质鉴定化合物结构。结果:分离鉴定了7个黄酮,分别为芹菜素(1)、木犀草素-3’-O-β-D-吡喃葡萄糖苷(2)、槲皮素-3-O-β-D-吡喃葡萄糖苷(3)、芦丁(4)、山奈酚-3-O-α-L-吡喃鼠李糖基(1→6)-β-D-吡喃葡萄糖苷(5)、芹菜素-7-O-(6″-E-p-香豆酰基)-β-D-葡萄糖苷(6)、芹菜素-6-C-(6″-E-p-香豆酰基)-β-D-葡萄糖苷(7)。结论:7个化合物均为首次从该植物中分离得到。 相似文献
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63.
We describe the chromosomal abnormalities found in 104 previously untreated patients with non-Hodgkin's lymphoma (NHL) and the correlations of these abnormalities with disease characteristics. The cytogenetic method used was a 24- to 48-hour culture, followed by G- banding. Several significant associations were discovered. A trisomy 3 was correlated with high-grade NHL. In the patients with an immunoblastic NHL, an abnormal chromosome no. 3 or 6 was found significantly more frequently. As previously described, a t(14;18) was significantly correlated with a follicular growth pattern. Abnormalities on chromosome no. 17 were correlated with a diffuse histology and a shorter survival. A shorter survival was also correlated with a +5, +6, +18, all abnormalities on chromosome no. 5, or involvement of breakpoint 14q11-12. In a multivariate analysis, these chromosomal abnormalities appeared to be independent prognostic factors and correlated with survival more strongly than any traditional prognostic variable. Patients with a t(11;14)(q13;q32) had an elevated lactate dehydrogenase (LDH). Skin infiltration was correlated with abnormalities on 2p. Abnormalities involving breakpoints 6q11-16 were correlated with B symptoms. Patients with abnormalities involving breakpoints 3q21-25 and 13q21-24 had more frequent bulky disease. The correlations of certain clinical findings with specific chromosomal abnormalities might help unveil the pathogenetic mechanisms of NHL and tailor treatment regimens. 相似文献
64.
目的:建立蒙药益智温肾十味丸的显微、薄层、理化鉴别方法和高效液相含量测定方法,提高其质量控制水平.方法:在显微镜下观察本品粉末,以种皮厚壁细胞、石细胞群和体壁碎片为指标,鉴别本品中益智、苦石莲、冬葵果和方海;提取挥发油,点样于硅胶GF254薄层板上,环己烷-乙酸乙酯(9∶1)展开,以标准药材为对照,鉴别本品中的益智;理化方法鉴别白硇砂中氯化铵和方海中碳酸钙.对荜茇中胡椒碱进行含量监控,用ODS填充的色谱柱,甲醇-水(77∶ 23)为流动相,343 nm波长下测定.结果:方法可有效鉴别本品中益智、苦石莲、冬葵果、方海和白硇砂5味药材,高效液相含量测定方法在0.040 4~0.282 8 μg线性良好(r=0.999 9),胡椒碱的平均回收率为98.1%,RSD 0.62%,含量限度为不得少于1.4 mg·g-1.结论:该方法可有效控制本品质量. 相似文献
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66.
ObjectiveTo determine the prevalence of asymptomatic bacteriuria in pregnancy, to consider the antimicrobial sensitivity patterns of involved uropathogens, to elucidate the safety profiles of antibacterial agents, and to evaluate the role of urinalysis in screening for asymptomatic bacteriuria.MethodsAbout 760 apparently healthy pregnant subjects attending the Antenatal Clinic of the University of Port Harcourt Teaching Hospital were randomly selected for this study. Urinalysis and microscopy, culture, and sensitivity tests were carried out on clean-catch midstream urine samples obtained from subjects. Biochemical reagent strips were used for urinalysis while the standard wire loop and agar diffusion technique were respectively employed for culture and susceptibility testing.ResultsA total of 111 samples yielded moderate or severe growth on culture after 48 hours comprising 35, 31, 27, and 18 isolates of Staphylococcus spp., Proteus spp., Klebsiella spp., and Escherichia spp, respectivehy. Urinalysis results were positive for the presence of nitrate reductase and leucocyte esterase activity in 17 urine samples of these 111 samples. The isolates showed a general sensitivity to the fluorinated quinolones and to Nitrofurantoin.ConclusionsThe prevalence of asymptomatic bacteriuria is 14.6%, with the predominant organism being Staphylococcus spp. Drugs used for treatment should have excellent fetal safety profiles, and a rapid screening test with a high negative predictive value for asymptomatic bacteriuria would be ideal. 相似文献
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68.
High-dose therapy and autologous peripheral blood stem cell transplantation for patients with lymphoma 总被引:3,自引:0,他引:3
Kessinger A; Armitage JO; Smith DM; Landmark JD; Bierman PJ; Weisenburger DD 《Blood》1989,74(4):1260-1265
Forty patients with refractory Hodgkin's disease (24 patients) or non- Hodgkin's lymphoma (16 patients) who were considered for high-dose therapy but not for autologous bone marrow transplantation (ABMT) due to BM metastases, previous pelvic irradiation, a history of marrow involvement by tumor or hypocellular marrow in conventional harvest sites received high-dose therapy and autologous peripheral blood (PB) hematopoietic stem cell transplantation. Disappearance of circulating neutrophils and development of RBC and platelet transfusion-dependence was followed, in the evaluable patients, by reappearance of 0.5 x 10(9)/L circulating granulocytes and sufficient platelets to obviate the need for platelet transfusions at a median of 25 days after transplantation. Twenty-three patients experienced a clinical complete remission (CR). The projected 2-year event-free survival was 24% for all 40 patients and 49% for the non-Hodgkin's lymphoma patients. The projected 18-month event-free survival for the Hodgkin's disease patients was 15%. PB stem cell transplantation provided an opportunity to administer high-dose salvage therapy to patients with refractory lymphoma who otherwise were not candidates for such therapy. For some of those patients, the high-dose therapy produced prolonged survival, free of tumor progression. 相似文献
69.
Autologous peripheral hematopoietic stem cell transplantation restores hematopoietic function following marrow ablative therapy 总被引:2,自引:0,他引:2
From ten patients with advanced malignant disease involving the bone marrow, autologous hematopoietic stem cells were collected from the peripheral blood during eight four-hour pheresis procedures and cryopreserved. No manipulations to increase the number of stem cells circulating in the blood were used during the collections. Following marrow ablative chemotherapy or chemoradiotherapy, the autologous cells were thawed and infused intravenously (IV). WBCs reappeared in the circulation at a median of eight days (range seven to 11 days) after stem cell infusion. Two patients died early, whereas the other eight reached normal numbers of circulating granulocytes that have persisted for up to greater than 20 months. These eight patients became independent of RBC transfusions (hemoglobin concentration greater than 10 g/dL) at a median of 27 days (range 11 to 58 days) after transplantation. One patient received platelet transfusions for counts less than 50 x 109)/L, one patient developed a clinical picture of idiopathic thrombocytopenic purpura, and six patients maintained a platelet count greater than 20 x 10(9)/L at a median of 23 days (range 14 to 25 days) following stem cell infusion. This technique allows patients ineligible for autologous bone marrow transplantation due to unacceptable anesthetic risks, prior pelvic irradiation, or bone marrow metastases to receive marrow ablative therapy. 相似文献
70.
In vitro autoradiographic and in vivo scintigraphic localization of somatostatin receptors in human lymphatic tissue 总被引:6,自引:0,他引:6
Reubi JC; Waser B; Horisberger U; Krenning E; Lamberts SW; Gebbers JO; Gersbach P; Laissue JA 《Blood》1993,82(7):2143-2151
Receptors for the neuropeptide somatostatin (SS) were evaluated in vitro and in vivo in various human lymphatic tissues, ie, thymus, spleen, and lymph nodes; thymic carcinoids and thymomas were also tested. The receptors were measured in vitro using receptor autoradiography on tissue sections incubated with the SS analog 125I- [Tyr3]-octreotide or 125I-[Leu8,D-Trp22,Tyr25]-SS-28. All tissues were SS-receptor positive for either radioligand, except the thymomas. In thymic tissue, the receptors were diffusely located in the medulla, presumably on epithelial cells. In the spleen, the red pulp was strongly labeled. In the lymph nodes, the germinal centers were preferentially labeled. In all tissues, the receptors were of high affinity (kd thymus, 0.84 nmol/L; kd spleen, 1.6 nmol/L; kd lymph node, 0.62 nmol/L) and specific for SS. Displacement by nanomolar concentrations of SS-14, SS-28, and octreotide was observed, as was guanosine triphosphate dependency. The in vivo visualization of somatostatin receptors was performed after injection of 111In-DTPA- octreotide and gamma-camera scintigraphy. The spleen, but not thymus or lymph nodes, were visualized. These data suggest an important role for SS in regulating immune functions through SS receptors in thymus, spleen, and lymph nodes. Furthermore, SS may regulate neuroendocrine functions in the thymus. 相似文献