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71.
Paola Villa 《Evolutionary anthropology》1992,1(3):93-104
The key argument for the identification of prehistoric cannibalism is provided by analysis of close similarities in the treatment of human and animal remains. Such analysis requires precise data on depositional context, meticulous excavation records, detailed bone modification studies, a relatively large sample of human and animal postcranial bones, and data on local mortuary practices. With the exception of Fontbrégoua Cave, these necessary conditions are lacking at all Stone Age European sites where it has been hypothesized that cannibalism occurred. The alternative hypothesis of secondary burial practices has been proposed informally for some sites and, in a more formal and detailed way, for Krapina and Fontbrégoua. However, this hypothesis does not have a higher probability, is not justified by current data, and uses ethnographic analogies to prop up interpretations of materials for which contextual data are missing or have been neglected. At Fontbrégoua, cannibalism remains the simplest and most plausible explanation of the evidence; at Krapina and other sites the available evidence is insufficient to prove either secondary burial or cannibalism. 相似文献
72.
73.
Bombesin production by human small cell carcinoma of the lung 总被引:5,自引:0,他引:5
G D Sorenson S R Bloom M A Ghatei S A Del Prete C C Cate O S Pettengill 《Regulatory peptides》1982,4(2):59-66
A series of continuous cell lines of human small cell carcinoma of the lung (SCCL) have been evaluated for the production of bombesin (BN). In early established cultures BN was detected in the medium of 9 out of 11 cell lines and in 6 out of 7 cell homogenates examined. Levels in the medium were frequently higher in cultures of later passages compared to earlier passages of the same line and low levels developed in the two previously negative cell lines. Plasma concentrations were greater than 80 pmol/l in 2 out of 27 (7%) randomly selected patients with SCCL. A culture (DMS 406) established from the tumor of a patient with the highest plasma level (1240 pmol/l) was the highest producer in vitro. The results indicate that BN, which has been demonstrated immunocytochemically to be present in normal bronchial mucosal cells, is frequently produced by SCCL in vitro but elevated plasma levels are infrequently found in patients with this neoplasm. 相似文献
74.
The effect of pre- and posttreatment incubation of UV-irradiated and ethyl methanesulphonate (EMS) treated cells with non-toxic concentrations of inhibitors of de novo purine synthesis (dnPS) on expression of potentially lethal and premutational damage at the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus in V79 cells has been examined. The concentrations of inhibitors used were shown to profoundly perturb de novo DNA synthesis, by measurements of [14C]formate uptake, and cell cycle progression by flow cytofluorimetry. Postincubation in 6-methyl mercaptopurine ribonucleoside (MMPR) usually but not invariably potentiated the cytotoxic effects of UV and EMS but azaserine (AZS) and methotrexate (MTX) were without effect. No effects on mutant frequencies were observed on posttreatment with any of these agents. Caffeine produced the least effect on dnPS, but invariably potentiated lethal damage. This potentiation of lethal damage is not mediated by dnPS inhibition as has been suggested for Chinese hamster ovary (CHO) cells. 相似文献
75.
The locus for sorbitol dehydrogenase (SORD, E.C. 1.1.1.14) has been shown to segregate with hexosaminidase A and mannose phosphate isomerase in a series of human-Chinese hamster somatic cell hybrids. Cytogenetic analysis supports the assignment to chromosome 15 and further defines the gene locus to the region 15pterq21.This research was supported by the Medical Research Council of Canada (MT 4061), the Children's Hospital of Winnipeg Research Foundation, Inc., and the Department of Health, Province of Manitoba (H.S.W.). 相似文献
76.
The sensitivities of 26 starch gel electrophoretic enzyme assays have been compared using HeLa human cells and A9 mouse cells grown in vitro.This research was supported by National Institutes of Health Grant No. USPHS GM 09966. 相似文献
77.
We have examined the effect of addition of hydroxocobalamin to growth medium on the activity of the adenosylcobalamin-requiring enzyme methylmalonyl CoA mutase in normal human fibroblasts and in mutant human fibroblasts derived from patients with inherited methylmalonicacidemia. The mutant cell lines were assigned to four distinct genetic complementation groups (cbl A, cbl B, cbl C, and cbl D), each deficient in some step in the synthesis of adenosylcobalamin from hydroxocobalamin. After control cells were grown in cobalamin-supplemented medium, mutase holoenzyme activity increased markedly in a time- and concentration-dependent fashion. Growth in cobalamin-supplemented medium had no effect on mutase activity in some mutant lines belonging to the cbl B group, while activity increased severalfold in other cbl B mutants and in all cbl A, cbl C, and cbl D mutants examined, although mutase activity was still <10% of control. Comparison of mutase holoenzyme activity and total propionate pathway activity suggests that enhancement of mutase activity in mutant cells after cobalamin supplementation to values 5–10% of control may be sufficient to overcome the inherited metabolic block and to restore total pathway activity to normal.This work was supported in part by a research grant from the National Institutes of Health (AM 12579). H. F. W. is a recipient of a traineeship from the National Institutes of Health (T01-GM02299). 相似文献
78.
Abla A. Creasey Helene S. Smith Adeline J. Hackett Kimie Fukuyama William L. Epstein Stewart H. Madin 《In vitro cellular & developmental biology. Plant》1979,15(5):342-350
Summary Three human melanoma cell lines derived from one primary and two metastatic tumors from three different patients were characterized
for growth properties usually associated with malignant transformation; these include cell morphology, growth rate, saturation
density, growth in semisolid media, colony-forming ability on contact-inhibited monolayers of normal fibroblasts and epithelial
cells, and tumorigenicity in immunosuppressed mice. Variations in expression of aberrant properties were evident among the
lines. One of the metastatic lines satisfied all the parameters of malignancy tested and the other showed a number of these
properties, whereas the primary essentially fulfilled only one. These results suggest that cultured melanoma cells reflect
the clinical variability often observed among melanoma patients and the metastatic melanoma seems to display a higher degree
of malignant transformation than the primary.
THis work was supported in part by USPHS Grant No. 5 T01 AI00332-06 from the National Institutes of Health, Contract E73-2001-N01-CP-3-3237
from the Virus Cancer Program of the National Cancer Institute, and USPHS Grant No. 0H00714-02 from the National Institute
for Occupational Safety and Health. 相似文献
79.
Lucy A. Barrett Wolfgang J. Mergner Benjamin F. Trump 《In vitro cellular & developmental biology. Plant》1979,15(12):957-966
Summary Segments of human thoracic aorta were maintained in long-term explant culture for 18 weeks in serum-supplemented medium. The
aortas were grossly normal in appearance, and random samples fixed for light microscopy prior to culture revealed a normal
morphology. The intima contained no more than five layers of smooth muscle cells. After 7 days in culture, the intima was
noticeably thicker than the uncultured segments. The increased thickness was due to proliferating smooth muscle cells and
production of extracellular material. After several months in culture, extracellular material consisting of collagen and flocculent
material was present in areas resembling atherosclerotic fibrous plaques. A peripheral growth, which formed around the explant,
was composed of fibroblastlike cells and added to the overall thickness of the intima. However, aortic segment maintained
for up to 2 months in serum-free culture medium showed no cellular proliferation. This study demonstrates that changes resembling
early stages of atherosclerosis occur in human aortas maintained in explant culture using routine culture procedures.
Supported in part by the Pangborn Fund and the Graduate School of the University of Maryland.
This is publication 443 from the Cellular Pathobiology Laboratory. 相似文献
80.
Tatsuro Koike 《生物化学与生物物理学报:生物膜》1978,509(3):429-439
A clonal cell line of mouse neuroblastoma cells was found to undergo morphological differentiation in the presence of a K+ ionophore, valinomycin, in the assay medium. This effect was blocked by increasing the concentration of KCl of the medium, suggesting that the changes in resting membrane potential and ion fluxes may be involved in the mechanism of the formation of neurites. No enhancement of the neurite formation was observed in salines containing high concentrations of KCl in the absence of valinomycin. Depolarizing agents including veratridine, gramicidin and ouabain did not stimulate the outgrowth of neurites. Neither electrophoretic mobility of the cells nor molecular anisotropy of fluorescence probes in the membranes was modified by the treatment of valinomycin. Instead, it modified the slow binding phase in kinetics of the interaction of 1-anilinonaphthalene-8-sulfonate (ANS) with the cells, which is related to the penetration process of the probe into membranes. Valinomycin also enhanced the fluorescence intensity of ANS by increasing the binding sites in neuroblastoma cells. 相似文献