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991.
Laterality is a quality, widespread throughout the vertebrate kingdom. It consists in assigning different roles to each side of the body by granting predominance to one of the sides. Humans too display this quality and the specialization of each hemisphere in our brain was already present in the first vertebrates. We usually refer to right-handed and left-handed people depending on the upper limb that is assigned the dominant role. For a long time, it has been thought that the proportion of left-handed people in a population has remained constant in all cultures and during our evolution. However, laterality is affected by sociocultural influences and varies geographically and chronologically. Using archaeological remains, it is possible to obtain information about the laterality of our ancestors and determine laterality indices for past populations. We developed an experimental programme to determine which characteristics of a polished axe indicate the laterality of its maker. We describe a method based on the orientation of the edge and we study the Neolithic and Chalcolithic farming communities in northern Iberia to evaluate the laterality in those populations. The right/left laterality ratio for the Neolithic and Chalcolithic populations is very similar to the range detected for modern non-industrial societies.  相似文献   
992.
We investigated 15,542 patients with suspected BCR-ABL1- negative myeloproliferative or myelodysplastic/myeloproliferative neoplasm (including 359 chronic myelomonocytic leukemia) by a molecular marker set. JAK2V617F was detected in the suspected categories as follows: polycythemia vera 88.3%, primary myelofibrosis 53.8%, essential thrombocythemia 50.2%, and not further classifiable myeloproliferative neoplasms 38.0%. JAK2 exon 12 mutations were detected in 40.0% JAK2V617F-negative suspected polycythemia vera, MPLW515 mutations in 13.2%JAK2V617F-negative primary myelofibrosis and 7.1% JAK2V617F-negative essential thrombocythemia. TET2 mutations were distributed across all entities but were most frequent in suspected chronic myelomonocytic leukemia (77.8%). CBL mutations were identified in suspected chronic myelomonocytic leukemia (13.9%), primary myelofibrosis (8.0%), and not further classifiable myeloproliferative neoplasm (7.0%). This leads to a stepwise workflow for suspected myeloproliferative neoplasms starting with JAK2V617F and investigating JAK2V617F-negative patients for JAK2 exon 12 or MPL mutations, respectively. In cases in which a myeloproliferative neoplasm cannot be established, analysis for TET2, CBL and EZH2 mutations may be indicated.Key words: myeloproliferative neoplasms, chronic myelomonocytic leukemia, molecular analyses, mutation screening, diagnostic workflow  相似文献   
993.
The combination of cytoreductive chemotherapy with reduced-intensity conditioning (RIC) is a highly effective antileukemic therapy. Purpose of this retrospective analysis was to evaluate the antileukemic efficacy and toxicity of clofarabine-based chemotherapy followed by RIC and allogeneic stem cell transplantation (SCT) for high-risk, relapsed, or refractory acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS). From May 2007 until October 2009, a total of 27 patients underwent allogeneic SCT after treatment with clofarabine and ara-C for 5d and RIC (4Gy TBI/cyclophosphamide/ATG). Prophylaxis of graft-versus-host disease (GvHD) consisted of cyclosporine and mycophenolate mofetil. Unmanipulated G-CSF mobilized PBSC (n=26) or bone marrow cells (n=1) were transplanted from unrelated (n=21) or matched related (n=6) donors. Non-hematological toxicities of this regimen mainly affected liver and skin and were all reversible. Seven patients relapsed within a median time of 5.7 months. The overall survival (OS) and relapse-free survival rates were 56% and 52% at 2 yr, respectively. In this cohort of patients, cytoreduction with clofarabine/ara-C (ClAraC) followed by RIC allogeneic SCT was well tolerated and showed good antileukemic efficacy even in patients with high-risk AML or MDS, with engraftment and GvHD-incidence comparable to other RIC regimens.  相似文献   
994.
995.
Heart failure (HF) is increasing worldwide and represents a major burden in terms of health care resources and costs. Despite advances in medical care, prognosis with HF remains poor, especially in advanced stages. The large patient population with advanced HF and the limited number of donor organs stimulated the development of mechanical circulatory support (MCS) devices as a bridge to transplant and for destination therapy. However, MCS devices require a major operative intervention, cardiopulmonary bypass, and blood component exposure, which have been associated with significant adverse event rates, and long recovery periods. Miniaturization of MCS devices and the development of an efficient and reliable transcutaneous energy transfer system may provide the vehicle to overcome these limitations and usher in a new clinical paradigm in heart failure therapy by enabling less invasive beating heart surgical procedures for implantation, reduce cost, and improve patient outcomes and quality of life. Further, it is anticipated that future ventricular assist device technology will allow for a much wider application of the therapy in the treatment of heart failure including its use for myocardial recovery and as a platform for support for cell therapy in addition to permanent long-term support.  相似文献   
996.
997.
998.
We assessed the susceptibility of secondary acute myeloid leukaemia (sAML) to graft-versus-leukaemia effects. Data from 2414 sAML patients in first (n = 2194) or second (n = 220) complete remission were included. They were given grafts from human leucocyte antigen (HLA)-matched sibling (MSD, n = 1085), 10/10 unrelated donor (MUD, n = 1066) or 9/10 mismatched unrelated donor (MMUD, n = 263). The 100-day incidence of grade II-IV acute graft-versus-host disease (GVHD) was 25% while 2-year incidence of chronic GVHD was 38%. Relapse rates declined steadily by duration of follow-up and were significantly lower in patients with chronic GVHD (P < 0·001). Limited (hazard ratio [HR] = 0·66, P < 0·001) and extensive (HR = 0·52, P < 0·001) chronic GVHD were associated with a lower incidence of relapse. Each grade III-IV acute (HR = 7·04, P < 0·001) as well as limited (HR = 1·42, P = 0·03) and extensive (HR = 3·97, P < 0·001) chronic GVHD were associated with higher non-relapse mortality (NRM). This translated to better overall survival (OS; HR = 0·61, P < 0·001) in patients with limited chronic GVHD. In contrast, grade III-IV acute and extensive chronic GVHD were associated with worse OS (HR = 3·16, P < 0·001 and HR = 1·21, P = 0·03, respectively). Further, in comparison to HLA-identical sibling recipients, MUD recipients had a lower risk of relapse (HR = 0·82, P = 0·03) but higher NRM (HR = 1·38, P = 0·004). In conclusion, these data demonstrate that sAML is susceptible to graft-versus-leukaemia effects.  相似文献   
999.
The purpose of this study was to examine care-seeking during fatal infant illnesses in under-resourced South African settings to inform potential strategies for reducing infant mortality. We interviewed 22 caregivers of deceased infants in a rural community and 28 in an urban township. We also interviewed seven local leaders and 12 health providers to ascertain opinions about factors contributing to infant death. Despite the availability of free public health services in these settings, many caregivers utilized multiple sources of care including allopathic, indigenous and home treatments. Urban caregivers reported up to eight points of care while rural caregivers reported up to four points of care. The specific pathways taken and combinations of care varied, but many caregivers used other types of care shortly after presenting at public services, indicating dissatisfaction with the care they received. Many infants died despite caregivers' considerable efforts, pointing to critical deficiencies in the system of care serving these families. Initiatives that aim to improve assessment, management and referral practices by both allopathic and traditional providers (for example, through training and improved collaboration), and caregiver recognition of infant danger signs may reduce the high rate of infant death in these settings.  相似文献   
1000.
Fetal calf serum (FCS) bears a potential risk for carrying diseases and eliciting immune reactions. Nevertheless, it still represents the gold standard as medium supplement in cell culture. In the present study, human platelet lysate (PL) was tested as an alternative to FCS for the expansion and subsequent chondrogenic differentiation of human adipose‐derived stem cells (ASCs). ASCs were expanded with 10% FCS (group F) or 5% PL (group P). Subsequently, three‐dimensional (3D) micromass pellets were created and cultured for 5 weeks in chondrogenic differentiation medium. Additionally, the de‐ and redifferentiation potential of human articular chondrocytes (HACs) was evaluated and compared to ASCs. Both HACs and ASCs cultured with PL showed strongly enhanced proliferation rates. Redifferentiation of HACs was possible for cells expanded up to 3.3 population doublings (PD). At this stage, PL‐expanded HACs demonstrated better redifferentiation potential than FCS‐expanded cells. ASCs could also be differentiated following extended passaging. Glycosaminoglycan (GAG) quantification and qRT–PCR of 10 cartilage related markers demonstrated a tendency for increased chondrogenic differentiation of PL‐expanded ASCs compared to cells expanded with FCS. Histologically, collagen type II but also collagen type X was mainly present in group P. The present study demonstrates that PL strongly induces proliferation of ASCs, while the chondrogenic differentiation potential is retained. HACs also showed enhanced proliferation and even better redifferentiation when previously expanded with PL. This suggests that PL is superior to FCS as a supplement for the expansion of ASCs and HACs, particularly with regard to chondrogenic (re)differentiation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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