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91.
92.
Stringer CB Finlayson JC Barton RN Fernández-Jalvo Y Cáceres I Sabin RC Rhodes EJ Currant AP Rodríguez-Vidal J Giles-Pacheco F Riquelme-Cantal JA 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(38):14319-14324
Two coastal sites in Gibraltar, Vanguard and Gorham's Caves, located at Governor's Beach on the eastern side of the Rock, are especially relevant to the study of Neanderthals. Vanguard Cave provides evidence of marine food supply (mollusks, seal, dolphin, and fish). Further evidence of marine mammal remains was also found in the occupation levels at Gorham's Cave associated with Upper Paleolithic and Mousterian technologies [Finlayson C, et al. (2006) Nature 443:850–853]. The stratigraphic sequence of Gibraltar sites allows us to compare behaviors and subsistence strategies of Neanderthals during the Middle Paleolithic observed at Vanguard and Gorham's Cave sites. This evidence suggests that such use of marine resources was not a rare behavior and represents focused visits to the coast and estuaries. 相似文献
93.
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes. 相似文献
94.
Maternal administration of granulocyte colony-stimulating factor improves neonatal rat survival after a lethal group B streptococcal infection 总被引:2,自引:0,他引:2
Novales JS; Salva AM; Modanlou HD; Kaplan DL; del Castillo J; Andersen J; Medlock ES 《Blood》1993,81(4):923-927
Maternally administered recombinant human granulocyte colony- stimulating factor (rhG-CSF) has been shown to cross the placenta and induce a peripheral neutrophilia and increases in the marrow and spleen neutrophil storage pools in fetal and newborn rats. In the present study, we have used this model system to investigate the efficacy of prenatally administered rhG-CSF on neonatal defense to a lethal challenge with Group B-beta hemolytic Streptococcus (GBS). Pregnant rats were injected with rhG-CSF twice daily beginning 6 days before parturition. At birth, all pups were infected with a dose of GBS that is lethal for 90% of infected pups (LD90). Survival was monitored daily for 5 days. Survival of infected pups from saline-treated mothers beyond 60 hours after infection was 10%. No difference in survival was observed among pups from mothers treated 2 and 4 days before parturition. In contrast, we determined that survival was 82.5% among infected pups from mothers treated for 6 days before parturition with rhG-CSF. Our results demonstrate that maternal administration of rhG- CSF augments neonatal defenses against a lethal bacterial challenge. 相似文献
95.
We previously showed that heparan sulfate (HS) is required for in vitro cytokine + chemokine-mediated maintenance of primitive human hematopoietic progenitors. However, HS preparations are mixtures of polysaccharide chains of varying size, structure, and protein-binding abilities. Therefore, we examined whether the long-term culture-initiating cells (LTC-IC) supportive capability of HS is attributable to an oligosaccharide of defined length and protein-binding ability. Oligosaccharides of a wide range of sizes were prepared, and their capability to support human marrow LTC-IC maintenance in the presence of low-dose cytokines and a single chemokine, macrophage inflammatory protein-1alpha (MIP-1alpha), was examined. LTC-IC supportive capability of HS oligosaccharides correlated directly with size and MIP-1alpha binding ability. A specific MIP-1alpha-binding HS oligosaccharide preparation of M(r) 10 kDa that optimally supported LTC-IC maintenance was identified. This oligosaccharide had the structure required for MIP-1alpha binding, which we have recently described. The present study defines the minimum size and structural features of LTC-IC supportive HS. 相似文献
96.
The effects of granulocyte-macrophage colony-stimulating factor (GM- CSF) are not confined to cells of the myeloid lineage. GM-CSF has been shown to have effects on mature T cells and both mature and immature T- cell lines. We therefore examined the GM-CSF responsiveness of murine thymocytes to investigate whether GM-CSF also affected normal immature T lymphocytes. The studies presented here indicate that GM-CSF augments accessory cell (AC)-dependent T-cell receptor (TCR)-mediated proliferation of unseparated thymocyte populations. To identify the GM- CSF responsive cell type, thymic AC and T cells were examined for GM- CSF responsiveness. We found that GM-CSF augmentation of TCR-induced thymocyte proliferation appears to be mediated via augmentation of AC function, and not via direct effects on mature single-positive (SP) thymocytes. Enriched double-negative (DN) thymocytes were also tested for GM-CSF responsiveness. GM-CSF induced the proliferation of adult and fetal DN thymocytes in an AC-independent and TCR-independent single- cell assay. Thus, in contrast to the SP thymocytes, a DN thymocyte population was directly responsive to GM-CSF. GM-CSF therefore may play a direct role in the expansion of DN thymocytes and an indirect role in the expansion of SP thymocytes. 相似文献
97.
Weisdorf DJ; Verfaillie CM; Davies SM; Filipovich AH; Wagner JE Jr; Miller JS; Burroughs J; Ramsay NK; Kersey JH; McGlave PB 《Blood》1995,85(12):3452-3456
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
98.
Alice K. Guidera BSc MBChB Patrick J. D. Dawes MBChB FRCS Amy Fong MBBS FRANZCR Mark D. Stringer MS FRCS 《Head & neck》2014,36(7):1058-1068
An accurate understanding of the arrangement of cervical fascia and its associated compartments is essential for differential diagnosis, predicting the spread of disease, and surgical management. The purpose of this detailed review is to summarize the anatomic, clinical, and radiological literature to determine what is known about the arrangement of cervical fascia and to highlight controversies and consensus. The current terminology used to describe cervical fascia and compartments is replete with confusing synonyms and inconsistencies, creating important interdisciplinary differences in understanding. The term “spaces” is inappropriate. A modified nomenclature underpinned by evidence‐based anatomic and radiologic findings is proposed. This should not only enhance our understanding of cervical anatomy but also facilitate clearer interdisciplinary communication. © 2014 Wiley Periodicals, Inc. Head Neck 36: 1058–1068, 2014 相似文献
99.
100.
Jason T. K. Woon Mark D. Stringer 《Anatomical science international / Japanese Association of Anatomists》2014,89(4):207-214
There has been no systematic study of the anatomy of the region between the sacral and coccygeal cornua. Reference texts describe an intercornual ligament connecting these structures. The aim of this study was to investigate the anatomy of this region, which may be relevant to unexplained cases of coccygeal pain (coccydynia) and local nerve blocks. The bony anatomy of the sacrococcygeal (SC) cornual region was analyzed in 33 CT scans obtained from supine adults of mostly European origin with no known SC pathology, 7 μCT scans of cadaver SC specimens, and 105 Asian Indian adult skeletons. A further five cadaver SC specimens were examined histologically. SC cornual fusion was seen in 45 % of CT/μCT scans (mean age 67 years, 20 males) and in 20 % of adult skeletons (78 males); there was no association with age or sex. In the absence of SC fusion, the mean intersacrococcygeal cornual gap was 7.1 ± 2.4 mm; this was bridged by an intercornual ligament composed of parallel vertical collagen fibers reinforced by elastin fibers on its anterior surface. Small nerve branches were observed adjacent to the ventral aspect of the intercornual ligament and, in one case, traversing the ligament. Ipsilateral sacral and coccygeal cornua are therefore normally bridged by an intercornual ligament that is probably innervated. The cornua are fused on one or both sides in 20–45 % of adults. These findings may have implications for some cases of coccydynia and for anesthetists performing local nerve blocks. 相似文献