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101.
Legitimizing surrogacy in Israel 总被引:3,自引:2,他引:1
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.
相似文献
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Tremblay MS Shephard RJ Brawley LR 《Canadian journal of public health. Revue canadienne de santé publique》2007,98(Z2):S1-S8
The Canadian Society for Exercise Physiology (CSEP), in partnership with Health Canada and others, released Canada's first physical activity guide for adults in 1998, with specific versions for older adults in 1999 and for children and youth in 2002. Research in the physical activity sciences (e.g., basic science, behavioural assessment, dose-response relationships, epidemiology, health messaging, physical activity measurement) has advanced rapidly since these publications. A detailed review of relevant current research is thus required, to assess whether the existing guidelines and resulting guides need revision or renewal. This introductory paper provides a brief chronology of events leading to the preparation of this journal supplement, including a statement of purpose and an overview of organization and content. A brief discussion of the purpose of the physical activity guidelines and guides, intended biological, psychological, and behavioural outcomes, and the way in which guidelines relate to on-going measurement and surveillance is provided as a context for the papers that follow. 相似文献
105.
Progressive platelet activation with storage: evidence for shortened survival of activated platelets after transfusion 总被引:14,自引:0,他引:14
HM Rinder ; M Murphy ; JG Mitchell ; J Stocks ; KA Ault ; RS Hillman 《Transfusion》1991,31(5):409-414
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) 相似文献
106.
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. 相似文献
107.
Otis W. Brawley MD 《Cancer》2015,121(13):2121-2123
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How many individuals will need to be screened to increase colorectal cancer screening prevalence to 80% by 2018? 下载免费PDF全文
110.
CML patients in blast crisis have breakpoints localized to a specific region of the BCR 总被引:1,自引:0,他引:1
Schaefer-Rego K; Dudek H; Popenoe D; Arlin Z; Mears JG; Bank A; Leibowitz D 《Blood》1987,70(2):448-455
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. 相似文献