人工神经元网络用于复方氯丙嗪的含量测定

将误差反向传播(BP)的人工神经元网络(ANN)模型，用于复方氯丙嗪紫外重叠光谱分 析。对ANN模型的参数进行了优化。采用f(x)二1/(1+e^-x)作为网络节点的输入输出转换函数的三 层神经网络具有较佳性能，当取隐含节点数为15时，该网络预测结果的最小平均相对误差为1.22％， 将研制的ANN模型用于复方氯丙嗪含量测定，其结果与药品标准法和偏最小二乘法(PLs)一致。     

庆大霉素在小鼠的时辰毒性及时辰药代动力学

本文研究了庆大霉素对小鼠的毒性及其药代动力学的昼夜节律性变化。雄性ICR小鼠自实验前两周置于标准的明期和暗期下饲养,自由进食进水。毒性实验剂量为庆大霉素290mg/kg,Sc:药代动力学实验剂量为45 mg/kg,Sc。结果表明,庆大霉素毒性及药代动力学因用药时间不同呈明显的昼夜节律性变化。明期中点用药毒性最大,血药浓度最高,AUC值最大:暗期用药毒性小,血药浓度低,AUC值小。提示了庆大霉素毒性的昼夜节律变化与其药代动力学的的昼夜节律变化有密切关系。     

吡唑烷酮类化合物的抗惊厥作用

对3类14种吡唑烷酮类化合物的抗惊厥作用进行了比较研究,它们对最大电休克惊厥均有对抗作用,作用出现快,但维持时间较短,其中II-f作用最强,对听源性发作和家兔海马注射硫酸锌形成的慢性癫痫模型也有效。此外,III-类尚能对抗戊四唑引起的阵挛性惊厥。     

Legitimizing surrogacy in Israel

Recently the Israeli Parliament passed legislation regarding all aspects of assisted reproductive techniques, including surrogacy. The main points of this legislation are presented and discussed. The most important aspects are: (i) a public committee authorizes and supervises every single case; (ii) only full surrogacy is permitted; (iii) the agreement is not commercial, reasonable expenses can be paid to the surrogate mother under the supervision of the Approving Committee; (iv) the surrogate mother must be single or divorced; (v) under certain conditions the surrogate mother can withdraw from the agreement; (vi) the child is under the tutelage of a social worker, representing the state, from birth until the completion of the adoption procedure. The religious, social and legal status of surrogate pregnancies worldwide are discussed.      

烯丙胺类抗真菌药物比较分子力场分析(CoMFA)的研究

本实验采用“活性类似物法”确定了烯丙胺类抗真菌化合物的药效构象,采用比较分子力场分析法(CoMFA)拟合了48个烯丙胺类抗真菌化合物对6种常见致病真菌的3D-QSAR方程,并比较了2种不同叠合规则对模型的影响,最后,用5个新合成化合物对所拟合的抗石膏样毛癣菌、抗烟曲霉菌的CoMFA模型的预测能力进行了检验,得到比较满意的结果。     

Progressive platelet activation with storage: evidence for shortened survival of activated platelets after transfusion

Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Analysis of clonal rearrangements of the Ig heavy chain locus in acute leukemia

Clonal rearrangements of the Ig heavy chain (IGH) locus occur in nearly all cases of B-cell precursor acute leukemia (BCP-ALL). Some of these rearrangements may be detected by polymerase chain reaction (PCR) using VH gene framework III (FRIII) and JH consensus primers. However, about 20% of BCP-ALLs fail to amplify with this technique. To determine the causes of these PCR failures and to investigate any possible association with specific subgroups of disease, we analyzed 72 acute leukemias of defined immunophenotype and cytogenetics, comparing FRIII with VH-family leader-specific PCR methods and Southern blotting. Of 37 BCP-ALL cases, 6 (16.2%) failed totally to amplify with FRIII and JH primers. None of these cases amplified with VH leader primers. Additionally, all cases retained germline VH6 genes and 5 of 11 rearranged alleles amplified with a consensus DH primer, indicating that these rearrangements represented biallelic DH-JH recombinations. Among the 6 FRIII and VH leader PCR-negative BCP-ALL cases, there was no common immunophenotype or consistent cytogenetic abnormality, although all showed structural chromosomal abnormalities and 3 of 5 successfully karyotyped had abnormalities of chromosome 12p. 13 cases with t(9;22)(q34;q11) Philadelphia chromosome-positive [Ph+]) and IGH rearrangements (9 BCP-ALL and 4 biphenotypic cases) were also analyzed. Of 23 rearranged IGH alleles, 19 (82%) were positive by FRIII PCR, and all 4 remaining alleles were amplified by VH leader primers. Use of the leader primers in these Ph+ cases also detected 3 additional clonal rearrangements that were not anticipated from Southern blotting; such unexpected bands were not observed in 21 other Ph- cases. The additional bands represented "new" and unrelated VH rearrangements rather than VH-VH replacement events. We conclude that biallelic DHJH rearrangements occur in a subgroup of BCP-ALL; in these cases, the activation of the full VHDHJH recombination mechanism had not occurred. Therefore, these cases of BCP-ALL were arrested at an early stage of B- cell differentiation. In contrast, all Ph+ BCP-ALLs and biphenotypic acute leukemias, which may represent the transformation of multipotent hemopoietic stem cells, had undergone VHDHJH recombination. Of 9 Ph+ BCP-ALL cases, 3 also showed ongoing VHDHJH rearrangement, reflecting the persistent expression of the VHDHJH recombinase. Finally, sequence analysis of 33 rearranged VHDHJH genes showed that only 3 including 2 Ph+ BCP-ALL maintained an intact open-reading frame. Loss of the open- reading frame occurred not only because of out-of-frame VHDH and DHJH joining, but also because of VH gene mutation and deletion. These data show that most BCP-ALLs may represent the neoplastic transformation of BCPs destined to die in the bone marrow.     

CML patients in blast crisis have breakpoints localized to a specific region of the BCR

Chronic myelogenous leukemia (CML) is associated with the Philadelphia (Ph) chromosome, which results from a reciprocal translocation between chromosomes 9 and 22. This activates the abl oncogene by moving it from chromosome 9 and combining it with sequence located on chromosome 22. The new fusion gene, with chromosome 22 sequence at its 5' end and chromosome 9-abl sequence at its 3' end, generates a new messenger RNA (mRNA) and protein that are implicated in the pathogenesis of CML. The breakpoint near the c-abl locus on chromosome 9 can occur within a large area. In contrast, the breakpoints on chromosome 22 are concentrated within a 6 kilobase (kb) region termed the breakpoint cluster region (bcr). This study was designed to determine whether chronic-phase and blast crisis patients had identifiable differences in the structure of their Ph chromosomes. Restriction mapping of the chromosome 22 translocation breakpoints performed for 26 patients showed that the breakpoints of eight of the nine patients in blast crisis were in the 3' portion of the bcr, whereas the breakpoints in the 17 patients in the chronic phase were clustered in the 5' portion of the bcr. This suggests a strong correlation between a 3' bcr breakpoint and blast crisis in CML.