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1.

The examination of a well‐documented petroglyph site, located near the northeastern shoreline of now‐dry Owens Lake, California, is used as a springboard for a review of explanatory models for the interpretation of rock art sites in California and the Great Basin. Interpretive models and methods of analysis used by Julian Steward, Robert Heizer, and others who have visited or reported on this site are reviewed. The persistence of Heizer's “hunting‐magic” explanation for the creation of the rock art is used as one of several examples of how preconceived notions can affect interpretations of ancient art.  相似文献   

2.
Abstract

Crosslinking experiments with various bifunctional reagents were used to investigate the nature and fate of the platelet growth factor (PDGF) receptor on Swiss mouse 3T3 cells. With ethylene glycol bis succinimidyl succinate (EGS) two bands with Mr 205′000 and Mr 190′000 were labeled at equal intensity, while with disuccinimidyl suberate (DSS) and the photoactivatable pazidophenylglyoxal (pAPG) almost exclusively the latter band was labeled, when analyzed by SDS polyacrylamide gel electrophoresis under reducing conditions. Evidence is presented that the Mr 190′000 band represents a Mr 175′000 receptor protein crosslinked to a single chain of the PDGF-dimer and the Mr 205′000 species the same Mr 175′000 protein crosslinked to both chains of PDGF. Pretreatment of cells with tunicamycin generated a third labeled band with Mr 150′000, while pretreatment with neuraminidase resulted in a shift of the Mr 205′000 and 190′000 bands by 5′000. This shows that the PDGF receptor is a sialoglycoprotein, consisting of a Mr β 135′000 proteinaceous core and a Mr β 40′000 carbohydrate moiety containing sialic acid. The virtually unchanged labeling intensity seen with tunicamycin and neuraminidase pretreated cells further suggests that the carbohydrate portion of the receptor is not required for PDGF binding. Finally, the crosslinking technique was used to show that at 37°C preformed 125I-PDGF receptor complexes disappear from the cell surface with a t1/2 β 8 min.  相似文献   

3.
《Journal of bryology》2013,35(1):153-156
Abstract

A collection of mosses made by Mr M. J. E. Coode in Sulawesi, comprizing 37 species, is reported upon. Five species appear to be unrecorded for this still bryologically littleknown island. Taxitheli'um capillarisetum appears to be the first gathering since the type collection (in New Guinea).  相似文献   

4.
The proteolipid subunit of H+-ATPase was labeled by [14C]N,N-dicyclohexylcarbodiimide in bovine heart mitochondria. The radioactive labeling was followed using various systems of sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). When using discontinuous SDS-PAGE (Laemmli, U.K., 1970,Nature (London)227, 680–685) a monomeric (Mr 7600±1500) and a dimeric form (Mr 17,800±1200) of the proteolipid were detected, while only the monomeric form was found on urea (8 M) containing gels (SDS-PAGE according to Laemmli; or Swank, R. T., and Munkers, K. D., 1971,Anal. Biochem. 39, 462–477). When using SDS-PAGE with Na-Pi buffer (Weber, K., and Osborn, M., 1969,J. Biol. Chem. 244, 4406–4442), only a dimeric form of the proteolipid (Mr 15,000±1000) was detected. Experimental data indicate that the different patterns of proteolipid separation are related to the presence of the two distinct proteolipid conformations in the SDS solution.  相似文献   

5.
 A Scleroderma species collected on sandy soil under trees of Lithocarpus edulis in Saitama Prefecture, central Japan, is identified as Scleroderma laeve, a new record for Japan. Macroscopic and microscopic features are given. Received: May 24, 2002 / Accepted: September 9, 2002 Acknowledgments We thank Ms. Ryoko Onuma, who offered some useful literature on Scleroderma. We are also grateful to Dr. Toshimitsu Fukiharu (Natural History Museum and Institute, Chiba) for his help with preserving the specimens. For collecting specimens, we are grateful to Ms. Ayano Kimura, Mr. Tomoya Matsuyama, and Mr. Takahiro Uchida. Correspondence to:T. Kasuya  相似文献   

6.
Abstract

This study was undertaken in order to improve photoaffinity labelling efficiency of pancreatic cholecystokinin receptor by the cleavable probe 125I-ASD-(Thr28, Ahx31)-CCK-25-33 and to further characterize the denaturated receptor and is agonist binding domain. Membrane bound pancreatic cholecystokinin receptor was specifically labelled by 125I-ASD-(Thr28, Ahx31)-CCK-25-33 as a component of Mr ≈ 85,000-100,000. The efficiency of the photolabelling was 3–4%. Performing photolysis on [125I-ASD-(Thr28, Ahx31)-CCK-25-33-receptor] complexes solubilized by CHAPS did not affect specificity of the labelling reaction but enhanced its efficiency so that up to 10% of the receptor site population could be cross-linked. Several lectins were tested for their ability to recognize and purify the cholecystokinin receptor denaturated by Nonidet P-40. Wheat germ agglutinin provided the best recovery and purification rate. The receptor was fully adsorbed on immobilized wheat germ agglutinin, while only a fraction was retained on ricin II (28%) and Ulex europaeus (28%), thus suggesting that the receptor is heterogeneously glycosylated. Finally, major labelled receptor fragments were generated by enzymatic digestion. There were: endoproeinase Glu-Mr → C ≈ 34,000; endoproteinase Glu-C/trypsin → Mr ≈ 12,000; chymotrypsinlendoproteinase Glu-C → Mr ≈ 16,000 and 12,000. The fragment of Mr 2 34,000 was deglycosylated to a component of Mr ≈ 22,000 whereas the other fragments were insensitive to deglycosylation Such results strongly suggest that cholecystokinin binding occurs in a non-glycosylated domain of the cholecystokinin receptor protein.  相似文献   

7.
8.
Abstract

A GABA / benzodiazepine/barbiturate receptor complex has been purified from bovine cerebral cortex by affinity chromatography on a benzodiazepine column. Depending on the detergent present during the isolation of the receptor (deoxycholate/Triton X-100 or CHAPS/Asolectin), and during the binding assays (Triton X-100 or CHAPS), the receptor displays different binding properties for the GABAA agonist [3H]muscimol and for the chloride ion channel blocking agent [35S]t-butylbicyclophosphoro-thionate (TBPS), whereas the binding properties for the benzodiazepine [3H] flunitrazepam are independent of isolation and assay conditions. Both methods of isolation yield a protein complex consisting of the same two subunits of Mr 53000 and Mr 57000. Therefore the different binding properties reflect different conformations of the isolated receptor protein. [3H] flunitrazepam binding to the CHAPS-purified receptor is stimulated by GABA and the barbiturate pentobarbital in a dose-dependent manner. Photo-affinity labeling of the purified receptor with [3H] flunitrazepam leads to incorporation of radioactivity into both subunits, but predominantly into the Mr 53000 band, as shown by fluorography. Proteolytic degradation by trypsin of the isolated photo-affinity labeled receptor in detergent solution proceeds via a labeled Mr 48000 polypeptide. Proteolytic destruction of the reversible [3H]flunitrazepam and [3H]muscimol binding activities requires > 100 fold higher concentrations of trypsin than the decomposition of the receptor polypeptides into fragments < Mr 10000.  相似文献   

9.
Abstract

Generation of anti-idiotypic antibodies (anti-Id) is a rapid and new approach to produce anti-receptor antibodies without isolation of the receptor. This report describes the production of polyclonal anti-ANF anti-Id antibodies. These antibodies could inhibit the binding of [125I]-ANF to its receptor on aortic smooth muscle cells. Immunoblot analysis of detergent Chaps-solubilized adrenal gland membranes indicated that these anti-Id antibodies could recognize an Mr 130,000 band under nonreducing condition and an Mr 70,000 band under reducing condition. In addition, these antibodies could slightly increase the production of cyclic GMP in aortic smooth muscle cells.  相似文献   

10.
Abstract

Partial proteolytic digestion of the mammary prolactin (PRL) receptor was used to generate receptor fragments and analyze their immunoreactivity and PRL binding properties. Tryptic digestion of the PRL receptor produced two immunoreactive fragments (Mr ≈ 30,000 and ≈ 15,000) that reacted with a monoclonal anti-PRL receptor antibody and still specifically bound PRL, while the complete immunoreactive PRL binding unit (Mr ≈ 42,000) disappeared. Neither chymotrypsin nor V8 protease were able to generate any immunoreactive receptor fragments. These receptor fragments may represent smaller PRL binding receptor form(s) of biological significance.  相似文献   

11.
《Plains anthropologist》2013,58(21):142-157
Abstract

Fragmentary skeletal material from a burial found near the Big Horn Mountains of north-central Wyoming was determined to constitute the remains of three individuals. The few artifacts in association provide little basis for an assessment of cultural affiliation, however, cranial characteristics suggest a close relationship to previously studied Siouan populations.

In February, 1962 Mr. Donald C. Grey of Sheridan, Wyoming submitted skeletal material recovered from the PK Burial Site in Sheridan County, Wyoming to Dr. William M. Bass for identification. Assistance in the analysis of the material was given by Mr. Donald C. Lacy, a graduate studentinphysicalanthropology. According to Mr. Grey (personal communication February 14, 1962), the PK Burial Site was discovered during the summer of 19 59 by a University of Illinois geology student, a member of a summer field crew based at Sheridan College, Sheridan, Wyoming. He discovered a human skull (See Fig. 1: a, b, and c) exposed in the side of a small hilltop overlooking a rodeo corral on a ranch west of Sheridan. The site is located in the foothills of the Big Horn Mountains.  相似文献   

12.

Background

Most investigations regarding the First Americans have primarily focused on four themes: when the New World was settled by humans; where they came from; how many migrations or colonization pulses from elsewhere were involved in the process; and what kinds of subsistence patterns and material culture they developed during the first millennia of colonization. Little is known, however, about the symbolic world of the first humans who settled the New World, because artistic manifestations either as rock-art, ornaments, and portable art objects dated to the Pleistocene/Holocene transition are exceedingly rare in the Americas.

Methodology/Principal Findings

Here we report a pecked anthropomorphic figure engraved in the bedrock of Lapa do Santo, an archaeological site located in Central Brazil. The horizontal projection of the radiocarbon ages obtained at the north profile suggests a minimum age of 9,370±40 BP, (cal BP 10,700 to 10,500) for the petroglyph that is further supported by optically stimulated luminescence (OSL) dates from sediment in the same stratigraphic unit, located between two ages from 11.7±0.8 ka BP to 9.9±0.7 ka BP.

Conclusions

These data allow us to suggest that the anthropomorphic figure is the oldest reliably dated figurative petroglyph ever found in the New World, indicating that cultural variability during the Pleistocene/Holocene boundary in South America was not restricted to stone tools and subsistence, but also encompassed the symbolic dimension.  相似文献   

13.
African Negro     
Abstract

Roger L. Stevens is Chairman of the Board of Trustees at the John F. Kennedy Center for the Performing Arts in Washington, D.C., which he championed and funded in its infant stage. Successful in the real estate business (he sold the Empire State Building at a fair profit) Mr. Stevens segued into the theatre, producing such Broadway shows as A Man For All Seasons, Tea and Sympathy, Annie and Deathtrap. He came to Washington as assistant to Lyndon B. Johnson and stayed to build the Kennedy Center and to develop a program which continues to be strong and diverse. Design's Executive Editor Jack Morrison, president of the American Theatre Association, recently interviewed Roger Stevens for our readers.  相似文献   

14.
Abstract

Gel filtration chromatography (with Sephadex G25, G50 and G100) was used to separate the different forms of thallium (Tl) and cadmium (Cd) in the cytosol fraction of Lemna minor and to examine the influence of the duration of metal exposure on the speciation of the two elements. A major proportion of Cd in the soluble phase was found to be bound to three groups of proteinaceous and polypeptide fractions; two of these, the high molecular weight protein fraction (Mr > 150,000) and the low polypeptide sized moieties of about Mr 1,500 or less were constitutive entities, whereas the intermediate sized fraction (Mr 7,000 - 8,000) could only be detected in plants previously exposed to Cd. After 12 days of exposure to Cd this fraction accounted for the greatest part of the bound Cd in Lemna tissues. Extending the period of exposure from 18 hours to 12 days resulted in a shift in the distribution of Cd between the low and intermediate fractions. Evidence for Tl-protein binding was limited and confined to the high molecular weight fraction, and most of the Tl in the soluble phase was present in a form closely allied to the free ion. The contrasting behaviour between the two elements has been interpreted in terms of the differences in their physicochemical properties.  相似文献   

15.
《Peptides》1988,9(5):945-955
Two endopeptidases displaying similar specificities towards peptide hormone substrates but differing in molecular size have been identified in rabbit heart and isolated by a combination of ion-exchange chromatography, gel filtration and preparative gel electrophoresis. These two enzymes share several properties with the previously described rabbit brain endooligopeptidase A. They were shown to produce, by a single peptide bond cleavage, [Met5] enkephalin and [Leu5]enkephalin from small enkephalin containing peptides. They also hydrolyze the Phe5-Ser5 bond of bradykinin and the Arg8-Arg9 bond of neurotensin. Characteristically, the activity of both low and high Mr enzymes is restricted to oligopeptides. Both forms of heart endooligopeptidase A are inhibited by antibodies raised against the brain enzyme. When electrophoresed in SDS-polyacrylamide gel under denaturing conditions, the low Mr heart enzyme shows a major band of Mr=73,000, comparable in size to the brain enzyme. The SDS-PAGE of the high and low Mr enzymes analyzed by immunoblotting with an antibody raised against low Mr brain endooligopeptidase A, showed a major antigen band corresponding to Mr=72,000. In addition, immunoblotting has also demonstrated that a monoclonal antibody antitubulin reacts with a polypeptide corresponding to Mr=50,000 present in the purified high Mr endooligopeptidase A. Both enzymes are activated by dithiothreitol and inhibited by thiol reagents, but are not affected by leupeptin, DFP or EDTA, thus indicating that they should be classified as nonlysosomal cysteinyl-endooligopeptidase A.  相似文献   

16.
H. Kobayashi  A. Yamada 《Mycoscience》2003,44(1):0061-0062
 Chlamydospores of Entoloma clypeatum f. hybridum were described on the mycorrhizas and rhizomorphs associated with Rosa multiflora. Their developmental pattern seems to be the Nyctalis type. This is the first report on chlamydospore formation on the mycorrhizae in entolomatoid fungi. Received: January 17, 2002 / Accepted: November 5, 2002 Acknowledgments K.H. is grateful to Emeritus Professor N. Sagara in Kyoto University, in whose laboratory part of this study was undertaken. Thanks are due to Mr. D. Sakuma for allowing the specimens to be kept in Osaka Museum of Natural History. Correspondence to:H. Kobayashi  相似文献   

17.
18.
The fire blight susceptible apple cultivar Malus × domestica Borkh. cv. ‘Gala’ was transformed with the candidate fire blight resistance gene FB_MR5 originating from the crab apple accession Malus × robusta 5 (Mr5). A total of five different transgenic lines were obtained. All transgenic lines were shown to be stably transformed and originate from different transgenic events. The transgenic lines express the FB_MR5 either driven by the constitutive CaMV 35S promoter and the ocs terminator or by its native promoter and terminator sequences. Phenotyping experiments were performed with Mr5‐virulent and Mr5‐avirulent strains of Erwinia amylovora, the causal agent of fire blight. Significantly less disease symptoms were detected on transgenic lines after inoculation with two different Mr5‐avirulent E. amylovora strains, while significantly more shoot necrosis was observed after inoculation with the Mr5‐virulent mutant strain ZYRKD3_1. The results of these experiments demonstrated the ability of a single gene isolated from the native gene pool of apple to protect a susceptible cultivar from fire blight. Furthermore, this gene is confirmed to be the resistance determinant of Mr5 as the transformed lines undergo the same gene‐for‐gene interaction in the host–pathogen relationship Mr5–E. amylovora.  相似文献   

19.
20.
Abstract

We have purified the luteinizing hormone (LH)/human choriogonadotropin (hCG) receptor to homogeneity by sequential affinity column on wheat germ lectin-Sepharose and hCG-Sepharose. The method was designed to allow also the purification of lactogen receptor from the initial starting material. Comparable purification of lactogen receptor can be attained using Con A-Sepharose as initial step. The purified LH/hCG receptor was identified as a single protein of Mr=75,000 on SDS gel electrophoresis. The lactogen receptor is composed of two dissimilar active subunits of Mr 88,000 and 40,000, the latter probably being an integral part of the larger form. Comparison of Mr's derived from SDS gels with those from fast performance liquid chromatography suggested that the native LH holoreceptor is present in a dimeric form, while the lactogen receptor seems to be composed of aggregates that could represent dimeric or trimeric forms of holoreceptor Mr 80,000. Cross-linking studies performed after binding of hCG (radiolabeled in the individual subunits) to the purified LH/hCG receptor indicated that the hCG α-subunit undergoes predominant interaction with the receptor molecule. The influence of the β-subunit in this interaction seems to occur mainly through its association with the α-subunit, presumably by conferring specificity to the α-subunit for its interaction with the receptor. The α-subunit, which is identical within species, has an important role in the receptor binding interaction and biological activity of glycoprotein hormones.  相似文献   

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