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141.
142.
刺南蛇藤倍半萜的研究 总被引:1,自引:0,他引:1
从刺南蛇藤(Celastrus flagelaris Rupr.)种子油中分离到八个β-二氢沉香呋喃倍半萜,经红外、紫外、质谱及核磁共振谱确定它们的结构是1α-乙酰氧基-2α,9β-二肉桂酰氧基-β-二氢沉香呋喃(1),1α,6β,13-三乙酰氧基-9β-苯甲酰氧基-β-二氢沉香呋喃-(2),triptogelinG-1(3),1α,6β-二乙酰氧基-9β-苯甲酰氧基-β-二氢沉香呋喃(4),triptogelinF-2(5),1α,2α-二乙酰氧基-9β-肉桂酰氧基-β-二氢沉香呋喃(6),celaforlinB-3(7),1α,6β-二乙酰氧基-8α-肉桂酰氧基-9α-苯酰氧基-β-二氢沉香呋喃(8)。其中1是新化合物,命名为celastrine B。 相似文献
143.
Selection of prostate cancer risk patients for surgical treatment has traditionally been accomplished by the creation of risk groups, like clinical stage, prostate specific antigen and others. Using these data knowledge-based expert systems were created. Among these the most popular model is the logistic regression model. Ideally, this prediction should be as accurate as possible. Many studies have shown that even expert on its field often are incorrect compared to the validated nomograms and artifical neural networks (ANNs) presented herein. Nomograms are instruments that predict outcomes for the individual patient using algorithms that incorporate multiple variables. Nomograms consist of a set of axes. Each variable is represented by a scale, with each value of that variable corresponding to a specific number of points according to its prognostic impact. In a final pair of axes, the total point value from all he variables is converted to the probability of reaching the end point By using scales, nomograms calculate the continuous probability of a certain outcome, resulting in more accurate predictions than models based on risk grouping. ANNs has gained increasing popularity and are the most popular artificial learning tool in biotechnology. This technique can roughly be described as a universal algebraic function that will distinguish dependency between dependent and independent variables, which is either unknown or very complex. The application of ANNs to complex relationships makes them highly attractive for the study of complexed medical decisions like predicting pathological stage or local recurrence after radical prostatectomy (RPE). Accuracy of nomograms and ANNs for pathological staging and PSA recurrence varies between 72–88.3% versus 77–91%, and 75–81% and 67–83%, respectively. 相似文献
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This study was designed to examine haemoglobin F levels prior to therapy in 39 patients with testicular tumours (10 seminoma, 29 non-seminomatous tumours) and 20 controls. HbF levels were significantly increased in the group with testicular tumours (1.66 +/- 0.12%) compared with normal controls (0.99 +/- 0.08%) (P less than 0.001). Non-seminomatous tumours had more pronounced levels than seminomas (P less than 0.001). No correlation was found between HbF level and stage of the disease. We suggest that HbF production could be significantly reactivated in adult patients with testicular tumours and may be a useful marker. 相似文献
147.
The individual infant's neurodevelopmental process provides an integrative framework for the delivery of medical care needed to assure the infant's survival and quality of outcome. The infant's neurobehavioral functioning and expression provides an opportunity for caregivers to estimate the individual infant's current strengths, vulnerabilities and threshold to disorganization, as well as to identify the infant's strategies in collaborating in his or her best progression. This perspective supports caregivers in seeing themselves in a relationship with the infant, and in considering opportunities to enhance the infant's strengths and reduce apparent stressors in collaboration with the infant and the family. The results of several randomized studies supporting the effectiveness of such a neuro developmental approach to NICU care will be presented, and suggest implications for staff education and nursery-wide implementation. 相似文献
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Kaynar K Dilli UD Akdogan R Akdogan E Ozdemir F Cobanoglu U Gul S Ulusoy S 《The Mount Sinai journal of medicine, New York》2006,73(8):1095-1097
Most hemodialysis patients exhibit renal anemia mainly due to erythropoietin deficiency as a result of impaired erythropoetin production in the kidney. However, erythrocytosis in patients with renal failure requiring hemodialysis is extremely rare. We report the development of erythrocytosis in a patient with a polycystic kidney disease on hemodialysis for 13 years. She had erythrocytosis with increased serum erythropoietin levels despite severe secondary hyperparathyroidism, which is known to depress erythrocytosis. Since neither renal disease (renal cell carcinoma) nor extrarenal diseases (hypoxia, hepatoma, cerebellar diseases) linked with erythropoietin production could be proven, this case might be one with inappropriate idiopathic erythropoietin production after 13 years of hemodialysis, the longest duration of dialysis in the literature before erythrocytosis was observed. 相似文献
150.