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1.
This is the text of the seventh Distinguished Lecture of the American Anthropological Association, presented at its 75th Anniversary Meeting in Washington, D.C., November 1976. The Lectureship was established in 1969 to honor outstanding scholars in the profession and the lecture is now published each year in the American Anthropologist. Adams is an archaeologist and comparative anthropologist whose research interests have centered on the ecologically oriented study of prehistoric patterns of land use, settlement, and urbanization. His fieldwork has been in the Middle East, particularly in Iraq. He has served on the faculty of the University of Chicago since 1955, receiving his Ph.D. there in 1956. Besides appointments in the departments of Anthropology and Near Eastern Languages and Civilization, he has been Director of the Oriental Institute and Dean of the Division of Social Sciences at Chicago. He was Chairman of the Division of Behavioral Sciences of the National Research Council and is a member of the National Academy of Sciences and a Fellow of the American Academy of Arts and Sciences. Adams' major publications include City Invincible (coeditor, 1960), Land Behind Baghdad (1965), The Evolution of Urban Society (1966, the Lewis Henry Morgan Lectures), and The Uruk Countryside (1972, with Hans J. Nissen).  相似文献   

2.
Progesterone was completely hydroxylated, principally to 11,14 dihydroxyprogesterone by Cunninghamella blakesleeana NCIM 687 in 48h.S.B. Chincholkar is with the Microbiology Division, Department of Life Sciences, North Maharashtra University, Jalgaon 425 001, India. R. Seeta Laxman is with the Division of Biochemical Sciences, National Chemical Laboratory, Pune 411 008, India. R.D. Wakharkar is with Organic Chemistry. Technology Division, National Chemical Laboratory, Pune 411 008. India  相似文献   

3.
Roelf Pot 《Hydrobiologia》1996,340(1-3):59-65
Changes in vegetation under reduced control measures over 3 to 5 years in watercourses in a rural environment in The Netherlands were evaluated. A method to deal with slow changes on a steep gradient is presented. The gradient with various vegetation types between the middle of the watercourse and the bank-top was split up into zones. Species composition of each zone was evaluated using literature on syntaxonomy. Cover of character species, multiplied by the width of the zones, was used to quantify the contribution of various syntaxa in the vegetation. Changes in these contribution data were used to evaluate changes over the years. The method was applied to two experiments in which cleaning frequency was reduced. Submerged vegetation of Callitriche-Ranunculetum penicillati in one and of Potamogetonetalia pectinati in the other case, hardly changed. Emergent vegetation of Nasturtio-Glycerietalia or Sparganio-Glycerietum fluitans tended to expand into the submerged zone. Bank vegetation began to show signs of development into ruderal vegetation, as a shift from Molinio-Arrhenatheretea into Artemisietea was detected. The method allowed the conclusion that conditions were too eutrophic in both experiments for a diverse brook vegetation development without additional habitat improvement.  相似文献   

4.
    
Mammalian brain tubulin is an heterodimer; both and exist in 6–7 isotypic forms which differ in their amino acid sequences. By the use of isotype-specific monoclonal antibodies, we have previously shown that we can purify the II, III, anda IV tubulin dimers from bovine brain. We have also observed that these isotypes differ in their distributionin vivo and their polymerization and drug-binding propertiesin vitro. We have now explored the question of whether the isotypically purified dimers differ in their overall conformation using as probes compounds of theN,N-polymethylenebis (iodoacetamide) series which are known to form discrete intrachain cross-links in-tubulin. These compounds have the structure ICH2CONH(CH2) n NHCOCH2I. One of these cross-links, designated s, is between cys12 and either cys201 or cys211. The other, designated *, is between cys239 and cys354. The * cross-link forms in II and IV but not in III; this is not surprising in view of the fact that III has serine at position 239 instead of cysteine. However, III is also unable to form the s cross-link, although it appears to have all three cysteines which may be involved in the cross-link. This suggests that at least one of the sulfhydryls involved in the cross-link may be inaccessible in III. Although both II and IV can form the s cross-link, the dependence on cross-linker chain length is different. II forms s with derivatives in whichn=2, 4, 5, 6, and 7 but not with those in whichn=3 or 10. In contrast, IV forms s with derivatives in whichn=2, 3, 4, 5, 6, 7, and 10. These results imply that the s sulfhydryls are slightly more accessible in IV and are therefore less dependent on the conformation of the cross-linker to react with it. It appears, therefore, that the II, III, and IV dimers each have unique conformations. This may help to explain the different assembly and drug-binding properties of these dimers.  相似文献   

5.
Restriction fragment analysis was used to examine the inheritance of lentil mitochondrial DNA (mtDNA) in F1 and F5 progeny from intrasubspecific (Lens culinaris ssp. culinaris) crosses and in F1 progeny from intersubspecific (Lens culinaris ssp. orientalis x L. culinaris ssp. culinaris) crosses. Southern blots of digested parental and progeny DNA were hybridized to heterologous maize mtDNA probes specific to coxI and atp6 genes. Two restriction fragment polymorphisms separated L.c. ssp. culinaris Laird and Eston from L.c. ssp. culinaris ILL5588, and one restriction fragment polymorphism distinguished L.c. ssp. culinaris Laird and Eston from L.c. ssp. orientalis LO4. Twelve of 13 f1 progeny and all F5 progeny from the intrasubspecific crosses, and all F1 progeny from intersubspecific crosses had only maternal mtDNA restriction fragments. One f1 plant from an Eston x ILL5588 cross inherited mtDNA fragments from both parents. Nuclear DNA inheritance was biparental in all F1 progeny.NRCC No. 38451  相似文献   

6.
For an amino acid in protein, its chemical shift, (, )s, is expressed as a function of its backbone torsion angles ( and ) and secondary state (s): (, )s=, )_coil+(, )_s, where (, )coil represents its chemical shift at coil state (s=coil); (, )s (s=sheet or helix) is herein defined as secondary structural effect correction factor, which are quantitatively determined from Residue-specific Secondary Structure Shielding Surface (RSS) for 13CO, 13C, 13C,1H, 15N, and 1HN nuclei. The secondary structural effect correction factors defined in this study differ from those in earlier investigations by separating out the backbone conformational effects. As a consequence, their magnitudes are significantly smaller than those earlier reported. The present (, )sheet and (, )helix were found varying little with backbone conformation and the 20 amino acids, specifically for 13CO, 13C, and 1H nuclei. This study also carries out some useful investigations on other chemical shift prediction approaches – the traditional shielding surfaces, SHIFTS, SHIFTX, PROSHIFT, and identifies some unexpected shortcomings with these methods. It provides some useful insights into understanding protein chemical shifts and suggests a new route to improving chemical shifts prediction. The RSS surfaces were incorporated into the program PRSI [Wang and Jardetzky, J. Biomol. NMR, 28: 327–340 (2004)], which is available for academic users at http://www.pronmr.com or by sending email to the author (yunjunwang@yahoo.com).  相似文献   

7.
With reciprocal rearing experiments, we tested the hypothesis that adaptive differences in host-use traits among soapberry bug populations have a genetic basis. These experiments were conducted with two host races from Florida, an ancestral-type one on a native host plant species and a derived one on a recently introduced plant species (colonized mainly post-1950), on whose seed crops this insect depends for growth and reproduction. Compared to the native host species, the introduced host produces larger seed crops over a much briefer annual period. Its seeds are also significantly higher in lipids and lower in nitrogen. The bug populations exhibit greater juvenile survivorship on their home hosts; that is, the derived population survives better on seeds of the introduced host than does its ancestral-type counterpart, and vice versa. Regardless of the rearing host, populations from the introduced host lay much smaller eggs, and fecundity measures show a more complex pattern than does survivorship: the ancestral-type population produces eggs at the same rate on each host, while the derived population is less fecund on the native host and exhibits enhanced fecundity on the introduced host. These results indicate that the population differences are evolved rather than host-induced. They appear to be adaptive responses to host differences in the spatial and temporal distribution of seed availability and nutritional quality, and show that increased performance on the alien host has evolved with surprising speed and magnitude, with concomitant reductions in performance on the original host.  相似文献   

8.
The association of the human -globin gene with the nuclear matrix was studied in erythroid and non-erythroid cell lines. Using a high salt method to prepare histone depleted nuclei we studied the association of variety of fragments covering a 7.8 kb region which contains the human -globin gene. We furthermore studied the association of a set of DNA fragments covering the 13 kb human G/A-globin gene domain, the 16 kb /-globin gene domain and the 10 kb -globin gene domain with the nuclear matrix of K562 and Raji cells. The results show that all fragments studied are easily released from the nuclear matrix, indicating no specific association.Summarizing our results we could say that a region starting 5.7 kb 5 to the human -globin gene and ending 4 kb 3 to the human -globin gene seems to contain no attachment sites with the nuclear matrix of both erythroid and non-erythroid cells.  相似文献   

9.
This test is a result of the past decade of studies investigating the vestibular sensitivity of individuals to Coriolis accelerations. A significant differentiation shown between the nonsick (NS) and the sick (S) subjects within each peer group (navigators, pilots, and nonflying personnel) indicates its value in testing the level of resistance an individual has to Coriolis accelerations; this supports its usefulness in determining an individual's resistance to motion sickness. The studies —conducted on experienced pilots (NS-299, S-51), navigators (NS-60, S-34), airman trainees (NS-91, S-19), and pentathlon athletes (NS-14, S-0) — demonstrate the usefulness of this test in the overall selection of personnel in preflight, postflight, and training programs.A version of this paper was read at the AGARD Conference on Predictability of Motion Sickness in the Selection of Pilots, North Atlantic Treaty Organization, in September, 1972, Glasgow, Scotland.The voluntary informed consent of the subject used in this research was obtained in accordance with AFR 80-33.The research reported in this paper was conducted by personnel of the Clinical Sciences Division, USAF School of Aerospace Medicine, Aerospace Medical Division, AFSC, United States Air Force, Brooks AFB, Texas. Further reproduction is authorized to satisfy the needs of the U.S. Government.  相似文献   

10.
Since the 1970's the management of aquatic habitats has changed from piecemeal monitoring to the ecosystem approach; this was initiated in the North American Great Lakes, comprising social, economic, and environmental aspects. The information included in this paper is based on the presentation made at the Seminar On Ecosystem Approach To Water Management held in Oslo, Norway during 1991. Recently, the multidisciplinary, holistic, and integrated concept of ecosystem health has emerged, and is being advanced for the implementation of an ecosystem approach to environmental management, which has resulted in the formation of an international society (Aquatic Ecosystem Health & Management Society) and the publication of a primary journal (Journal of Aquatic Ecosystem Health). The information has been updated to incorporate new developments and recent progress about the Society and the journal since the Oslo Seminar.  相似文献   

11.

Background:

Understanding the health care experience of people with dementia and their caregivers is becoming increasingly important given the growing number of affected individuals. We conducted a systematic review of qualitative studies that examined aspects of the health care experience of people with dementia and their caregivers to better understand ways to improve care for this population.

Methods:

We searched the electronic databases MEDLINE, Embase, PsychINFO and CINAHL to identify relevant articles. We extracted key study characteristics and methods from the included studies. We also extracted direct quotes from the primary studies, along with the interpretations provided by authors of the studies. We used meta-ethnography to synthesize the extracted information into an overall framework. We evaluated the quality of the primary studies using the Consolidated Criteria for Reporting Qualitative Research (COREQ) checklist.

Results:

In total, 46 studies met our inclusion criteria; these involved 1866 people with dementia and their caregivers. We identified 5 major themes: seeking a diagnosis; accessing supports and services; addressing information needs; disease management; and communication and attitudes of health care providers. We conceptualized the health care experience as progressing through phases of seeking understanding and information, identifying the problem, role transitions following diagnosis and living with change.

Interpretation:

The health care experience of people with dementia and their caregivers is a complex and dynamic process, which could be improved for many people. Understanding these experiences provides insight into potential gaps in existing health services. Modifying existing services or implementing new models of care to address these gaps may lead to improved outcomes for people with dementia and their caregivers.The global prevalence of Alzheimer disease and related dementias is estimated to be 36 million people and is expected to double in the next 20 years.1 Several recent strategies for providing care to patients with dementia have highlighted the importance of coordinated health care services for this growing population.25 Gaps in the quality of care for people with dementia have been identified,68 and improving their quality of care and health care experience has been identified as a priority area.25Incorporating the health care experience of patients and caregivers in health service planning is important to ensure that their needs are met and that person-centred care is provided.9 The health care experience of people with dementia and their caregivers provides valuable information about preferences for services and service delivery.10 Matching available services to patient treatment preferences leads to improved patient outcomes11,12 and satisfaction without increasing costs.13 Qualitative research is ideally suited to exploring the experiences and perspectives of patients and caregivers and has been used to examine these experiences for other conditions.14 We performed a systematic review and meta-ethnographic synthesis of qualitative studies exploring the health care experience of people with dementia and their caregivers in primary care settings, and we propose a conceptual framework for understanding and improving these health care experiences.  相似文献   

12.
Summary Growth ring analysis was carried out on root systems of Sitka spruce trees which had been planted for 8 and 34 years. Retrospective measurements were made on cross-sectional area increment near the root base. Differentiation of the main laterals into roots of widely different radial growth rates took place mainly during the first eight years, resulting in 3–11 major woody roots and a larger number of small minor ones, with some of intermediate vigour. The major roots established during the first few years constituted the main structural root system at 34 years. Many of the minor roots stopped growing in diameter after a few years, but were still alive and extending at 34 years. The differentiation into major and minor roots is discussed with reference to their origins and the local environment.  相似文献   

13.
Hydrophilic benzo[b]thiophene metabolites produced by Rhodococcus sp. strain T09 were isolated by a solid-phase extraction and a derivatization method, which prevented the dehydration that often occurs during liquid-liquid extraction (LLE), and were identified by GC with atomic emission detection and GC-MS. As a result, cis- or trans-2-(2-hydroxyphenyl) ethen-1-ol, previously reported as the tautomer 2-(2-hydroxyphenyl) ethan-1-al, and 2-(2-hydroxyphenyl) ethen-1-sulfenic acid and its isomer, 1-(1-hydroxyethenyl) benzene-2-sulfenic acid, were identified. Benzothiophene desulfurization in culture broth at neutral pH by the strain T09 was modified as a branched metabolism from benzothiophene S-oxide based on the above compounds.  相似文献   

14.
Selectivity coefficients (W) and predation rates on Lake Michigan zooplankton were determined forMysis relicta during spring through fall using anin situ method. W values indicated the following ranked order of prey preference: Cladocera > copepod copepodites and copepod nauplii > adult diaptomids and cyclopoids. With few exceptions, W values for different prey categories remained fairly constant despite greatly changing relative abundances of prey. Predation rates and prey selectivity were similar in most cases to those determined in laboratory studies. Ingestion rates (percent dry body weight · day–1) were correlated to total prey biomass (r = 0.38) and to effective prey biomass (r = 0.85), where the weighting factors were overall mean selectivity coefficients for the different prey categories. This result suggested that seasonally varying composition of prey caused much of the variation in ingestion rates among experiments. Feeding trials performed at the same depth with daytime and nighttime assemblages of zooplankton indicated that Cladocera may escape heavyMysis predation at night by migrating from the metalimnetic-hypolimnetic interface into the epilimnion.Contribution 333 from the Great Lakes Research Division, The University of Michigan and contribution 287 from the Great Lakes Environmental Research Laboratory, National Oceanic and Atmospheric Administration.Contribution 333 from the Great Lakes Research Division, The University of Michigan and contribution 287 from the Great Lakes Environmental Research Laboratory, National Oceanic and Atmospheric Administration.  相似文献   

15.
An undescribed bisexual grasshopper species closely related to the all-female parthenogenetic Moraba virgo has an X1X2Y sex chromosome mechanism which incorporates 7 chromosomes of the ancestral karyotype (the original X and three pairs of autosomes). Apparently three separate chromosomal fusions have occurred, one of these being a tandem fusion followed by a crossover which stabilized it in the sex chromosome system. M. virgo probably arose from an ancestor which had X1X2Y males but lacked the tandem fusion present in the new species, the females of virgo having the constitution X1X1X2O.Supported by Public Health Service Grant GM-07212 from the Division of General Medical Sciences, U.S. National Institutes of Health, and by a grant from the Australian Research Grants Committee.  相似文献   

16.
Summary The inhibition of D-Amino Acid Oxidase by -Keto Acid, product of the reaction with D-Amino Acid is described for the first time. Inhibition of the enzyme by -Keto--Methiolbutyric Acid (4-methylthio-2-oxobutanoic acid), product of the reaction with D-Methionine, was studied. From the results obtained it is deduced that inhibition is competitive with the substrate, the value of the inhibition constant being 1.85 10–3 M.  相似文献   

17.
18.
A wild-type strain of Rhodococcus equi, isolated from soil, degraded cholesterol, -sitosterol, stigmasterol and mixed sterois to androst-4-ene-3,17-dione (AD) and androsta-1,4-diene-3,17-dione (ADD). A definite preference for a relatively simply structured cholesterol side chain was observed. Highest specific cholesterol side-chain cleavage was associated with active growth of the culture. Maximum yield of ADD was obtained when sodium acetate and cholesterol were incorporated together in the medium. Specific side-chain cleavage required the presence of 2,2-dipyridyl, an inhibitor of ring cleavage.S. Ahmad and B.N. Johri are with the Department of Microbiology, College of Basic Sciences and Humanities, G.B. Pant University of Agriculture and Technology, Pantriagar 263 145, Nainital, UP, India. P.K. Roy, A.W. Khan and S.K. Basu are at Fermentation Technology Division, Central Drug Research Institute, Lucknow, India.  相似文献   

19.
Poly (A+)-mRNA obtained from human term placenta using guanidine HCl and oligo (dT) cellulose chromatography was translated in a wheat germ cell-free system. SDS-polyacrylamide gel electrophoresis analysis of the translation products revealed the presence of several polypeptides with molecular weights ranging from 10 KD to 70 KD. A single protein band representing around 1% of the total radioactive proteins synthesized in the presence of 2.5 g of mRNA was isolated by immunoprecipitation, using specific antiserum against either the native Pregnancy-specific 1-glycoprotein or a reduced and carboxymethylated derivative. The molecular weight of 31–2 KD of this translation product corresponding to the nonprocessed precursor could account for the 43 KD value assigned to the protein purified from human pregnant serum.  相似文献   

20.
Summary An electron microscope study of the reactive process taking place in the proximal segment of sectioned dorso-spinal nerves of white mice was carried out in about 50 animals. Attention was mainly directed to the study of the earliest changes (30) observable in the neuroplasm but the series of experiments included the study of nerves fixed up to 20 days after section.Most of the facts found (existence of microvesicles, multiplication of mitochondria, and presence of multivesicular bodies) confirmed the observation done in a preceding investigation, plus some non-described new findings.Early after section (30) the nerve membrane is seen, in some cases, masked by the presence of microvesicles which seem to take origine from the membrane which also shows deep infoldings. These coalesce in many places taking thus the appearance of rows of vesicles.At later stages (60, 80) this reactive process is more general in the nerve stumps and vast areas of microvesicles are seen in the fiber neuroplasm. This kind of reaction (membrane infolding and coalescence) decrease later on and is rarely observable at 100. Microvesicles are nevertheless increasing in number and many of them change their round profile for an elongated shape. Elongation leads to the formation of tubuli of progressively thinner diameter. This process is described as a possible way of neurofilament formation.This research was supported by the United States Air Force under Contract No AF 49 (638) 585 and Grant AF 61–64, monitored by the Air Force Office of Scientific Research, Air Force Research Division of the Air Research and Development Command.  相似文献   

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