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1.
P Lavie 《Chronobiology international》1992,9(2):83-96; discussion 97-101
This article describes the works of two 19th-century chronobiologists. Thomas Laycock (1812-1876), who held the Chair of Medicine in Edinburgh from 1855-1876, published a series of seven articles in Lancet, all dedicated to periodicities in "vital phenomena." Laycock considered the understanding of periodicities essential for the advancement of the treatment of diseases. Edward Smith (1818-1874) was a pioneer in experimental chronobiology. In his 1861 book entitled: Health and disease as influenced by daily, seasonal and other cyclical changes in the human, Smith summarized a large number of experiments in which he investigated the occurrence of periodicities in pulse rate, urine flow, urea excretion, and respiration. From his experimental results and those of others, Smith drew practical conclusions regarding patients' care, the timing of drug administration, and the design of night work.  相似文献   

2.
This article describes the works of two 19th-century chronobiologists. Thomas Laycock (1812-1876), who held the Chair of Medicine in Edinburgh from 1855-1876, published a series of seven articles in Lancet, all dedicated to periodicities in “vital phenomena.” Laycock considered the understanding of periodicities essential for the advancement of the treatment of diseases. Edward Smith (1818-1874) was a pioneer in experimental chronobiology. In his 1861 book entitled: Health and disease as influenced by daily, seasonal and other cyclical changes in the human, Smith summarized a large number of experiments in which he investigated the occurrence of periodicities in pulse rate, urine flow, urea excretion, and respiration. From his experimental results and those of others, Smith drew practical conclusions regarding patients' care, the timing of drug administration, and the design of night work.  相似文献   

3.
Five species of the genus Catomus Allard, 1876 Allard, E. (1876): Révision des Helopines vrais de Lacordaire. L'Abeille. Journal d'Entomologie, 14, 180. [Google Scholar] are known from Iran. Catomus fragilis (Ménétriés, 1848) is recorded from Iran for the first time. Lectotypes of C. persicus Allard, 1876 Allard, E. (1876): Révision des Helopines vrais de Lacordaire. L'Abeille. Journal d'Entomologie, 14, 180. [Google Scholar] (type species of the genus) and C. semiruber Allard, 1876 Allard, E. (1876): Révision des Helopines vrais de Lacordaire. L'Abeille. Journal d'Entomologie, 14, 180. [Google Scholar] are designated. These species are also redescribed and figured. A key to the species of Catomus in the Iranian fauna is given.  相似文献   

4.
记述采自中国四川省的菜花露尾甲属菜花露尾甲亚属1新种:淡翅菜花露尾甲Meligethes(Meligethes)pallidoelytrorum Chen&Kirejtshuk sp.nov.。对其特征作了描述,提供了成虫形态及雌雄外生殖器特征图。新种的主要鉴别特征为:虫体背部体表光滑,鞘翅具稀疏的刻点,跗爪基部具明显的齿。并提出滑菜花露尾甲M.(M.)lutra Solsky,1876和蜜菜花露尾甲M.(M.)melleus Grouvelle,1908是长唇菜花露尾甲M.(M.)vulpes Solsky,1876的新异名。  相似文献   

5.
Two new species of hyalellid amphipods, Hyalella crawfordi and H. gauthieri, are described from Lake Titicaca; H. echinus (Faxon, 1876) is redescribed. The H. echinus group of species is newly proposed for these three species, and a group diagnosis is provided. A key to the three species in the group is provided Full article published online at http://www.senckenberg.de/odes/06-10.htm.  相似文献   

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7.
Previous studies of L. Danziger and G. Elmergreen (Bull. Math. Biophysics,16, 15–21, 1954;18, 1–13, 1956) of possible biochemical periodicities in organisms assumed non-linear biochemical interaction between different metabolites, because linear systems do not lead to undamped ocsillations. They treated homogeneous systems. Later N. Rashevsky generalized their results to a more realistic case where the non-homogeneity due to the histological structure is considered. (Some Medical Aspects of Mathematical Biology, Springfield, Illinois: Charles C. Thomas, Publisher, 1964;Bull. Math. Biophysics,29, 389–393, 1967.) As long as the histological structure remains constant, the existence of sustained periodicities requires the assumption of non-linearity of biochemical interactions. If, however, the secretions of an endocrine gland affect the histological structure of the target organ, notably as in the menstrual cycle, and if there is a feed-back, the equations become non-linear and may admit sustained periodic solutions even if the purely biochemical interactions are linear.  相似文献   

8.
SHORT NOTES     
Laycock, H. T. 1982. Moulting and plumage changes in the Thickbilled Weaver. Ostrich 53:91-101.

Thickoilled Weavers were studied in captivity, in the wild and as museum specimens. Moulting follows the normal passerine pattern, but a difference from related species is that there is no post-fledging moult of the flight feathers. Methods were devised for identifying isolated feathers and for aging trapped birds, this being easier in the male. After the breeding season the male undergoes eclipse, which has apparently not been described before, and loses his white forehead patches. Adult males and females moult about the same time, but second-year males moult six or eight weeks earlier. The duration of post-nuptial moult is about four months and is timed to occur during the season when there is maximum food availability. The use of a “moult score” is avoided in this account and the timing of feather loss substituted as having more real meaning.  相似文献   

9.
Previous research has demonstrated that great ape and macaque males achieve large canine crown sizes primarily through extended canine growth periods. Recent work has suggested, however, that platyrrhine males may achieve larger canine sizes by accelerating rather than prolonging growth. This study tested the hypothesis that the ontogenetic pathway leading to canine sexual dimorphism in catarrhines differs from that of platyrrhines. To test this hypothesis, males and females of several catarrhine genera (Hylobates, Papio, Macaca, Cercopithecus, and Cercocebus) and three platyrrhine genera (Cebus, Ateles, and Callicebus) were compared in the number and spacing of perikymata (enamel growth increments) on their canine crowns. In addition, perikymata periodicities (the number of days of growth perikymata represent) were determined for five genera (Hylobates, Papio, Macaca, Cebus, and Ateles) using previously published as well as original data gathered for this study. The central findings are as follows: 1) males have more perikymata than females for seven of eight genera (in five of the seven, the differences are statistically significant); 2) in general, the greater the degree of sexual dimorphism, the greater the sex difference in male and female perikymata numbers; 3) there is no evidence of a systematic sex difference in primate periodicities; and 4) there is some evidence that sex differences in enamel formation rates may make a minor contribution to canine sexual dimorphism in Papio and Cercopithecus. These findings strongly suggest that in both catarrhines and platyrrhines prolongation of male canine growth is the primary mechanism by which canine crown sexual dimorphism is achieved. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

10.
Ammonia and Elphidium collected in the Kiel Fjord for the present study were first identified on morphological bases as Ammonia beccarii (Linné, 1758) and Elphidium excavatum (Terquem, 1876). Phylogenetic analyses based on partial SSU rDNA and LSU rDNA sequences show that Ammonia specimens sampled in the Kiel Fjord belong to the phylotype T6, which has a disjunct distribution (Wadden and Baltic Seas/China and Japan) and has been identified as Ammonia aomoriensis (Asano, 1951). Partial SSU rDNA sequence analyses indicate that Elphidium specimens from the Kiel Fjord belong to the clade E. excavatum, confirming the morphological identification. This clade can be further divided in three subclades. Kiel Fjord Elphidium belong to two of these subclades and were identified morphologically as the subspecies E. excavatum excavatum (Terquem, 1876) and E. e. clavatum Cushman, 1930.  相似文献   

11.
Previous suggestions of introgression between Agropyron spicatum (Pursh) Scribn. & Smith, 2n = 14 & 28, and Agropyron dasystachyum (Hook.) Scribn., 2n = 28, were confirmed. Fertile, meiotically regular, 28-chromosome plants morphologically identical to Agropyron albicans Scribn. & Smith, 2n = 28, occurred in first- and second-generation open-pollination progenies of diploid A. spicatum × A. dasystachyum hybrids, presumably by backcrossing to A. dasystachyum. These A. albicans-like derivatives were fully cross-compatible with naturally occurring A. albicans. First and second generation open-pollination progeny of tetraploid A. spicatum × A. dasystachyum F1's contained approximately 5% A. albicans-like plants; but none was tetraploid, cytologically stable, and fertile. Although introgression occurs freely between tetraploid A. spicatum and A. dasystachyum, derivation of fertile true-breeding A. albicans from their early-generation progeny seems unlikely. Agropyron griffithsii Scribn. & Smith ex. Piper, the glabrous counterpart of A. albicans, probably originated from hybrids between diploid A. spicatum and Agropyron riparium Scribn. & Smith, the glabrous form of A. dasystachyum. Genome formulas of diploid A. spicatum, A. dasystachyum (riparium), and A. albicans (griffithsii) may be written as S1S1, S2S2XX, and S1-2 S1-2XX, respectively. The relationship between A. albicans and A. dasystachyum is so close that A. albicans should be regarded as no more than a subspecies of A. dasystachyum.  相似文献   

12.
Lavie has written an admirably clear account of some of the work of Laycock and Smith, two researchers whom he considers to be pioneers of chronobiology. In making an assessment of this claim, we will consider two areas in particular: collecting data and interpreting results.  相似文献   

13.
Abstract

Fourier analysis of the short-range periodicities for the complete set of sequences coding for tRNA genes in genome of Bacillus subtilis proves that periodicities with periods p = 2, 3, 4, and 6 sites are the inherent properties of tRNAs. The related periodicities should be understood in a broad statistical sense and their identifying needs the elaborate statistical methods. To improve the statistics, the analysis of significant periodicities was performed for the binary R-Y, S-W, and K-M sequences. Generally, such short-range periodicities are produced via biased positioning of particular nucleotides rather than via the tandem multiplication and subsequent modifications of repeats, though the latter mechanism may also be realized. Quasi-coherently piercing long segments of tRNA, the short-range periodicities create the effective long-range structural coupling between the acceptor stem and the anticodon loop and may participate in the mechanisms of molecular recognition. The periodicities with p = 2 and 4 provide the natural ground for the translation with spontaneous or programmed frameshifting and are present in tRNAs decoding the most frameshift-prone codons. The observation of short-range periodicities suggests that the mechanisms of amino-acylation of tRNAs and codon-anticodon pairing are not independent. Their study may also provide the important information related to the origin and evolution of the genetic code.  相似文献   

14.
On the basis of reproductive anatomy and radula, the poorlyknown genus Mainwaringia Nevill, 1885, is shown to belong tothe Littorinidae. The genus is represented by two species, M.leithii (E.A. Smith, 1876) from India to Vietnam, and a newspecies, M. rhizophila, from Malaysia to Hong Kong. Both occurin mangrove forests. The reproductive anatomy of M, rhizophilais described in detail, and it is interpreted as a protandroushermaphrodite, a condition unique in the Littorinacea. In theintersexual and female stages both closed pallial oviduct andopen prostate are present in the mantle wall, suggesting thatthese structures are not strictly homologous. The affinitiesof Mainwaringiaare discussed, and it is concluded that it maybe most closely related to Littorina s.s. (Received 30 May 1986;  相似文献   

15.
We established a plant regeneration system for Hinoki cypress (Chamaecyparis obtusa) via somatic embryogenesis. Embryogenic tissues were successfully induced on three kinds of Smith media from megagametophyte explants containing pre-cotyledonary embryos of C. obtusa plus-trees. Factors affecting somatic embryo maturation were examined. The concentration of polyethylene glycol 4000 in the medium was a critical factor for embryo maturation and its effective concentration was 150 g/l. The addition of 30 g/l maltose to the medium had a positive effect on embryo maturation, but sucrose was ineffective. The mature somatic embryos germinated at a germination frequency of approximately 60%, and the presence of activated charcoal was effective in stimulating plantlet growth. The plantlets acclimatized successfully in a greenhouse. To our knowledge, this is first report describing details of a plant regeneration method for C. obtusa via somatic embryogenesis.Abbreviations ABA Abscisic acid - PEG Polyethylene glycol 4000 - SM1 Smith Standard Embryonic Tissue Capture Medium - SM2 Smith Standard Embryogenesis Medium - SM3 Smith Embryo Develop Medium  相似文献   

16.
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18.
The taxonomy of the Australian species of two Ropalidia species groups, the R. stigma group and R. variegata group, is revised and their distribution patterns are discussed. Two species in the R. stigma group (R. darwini and R. elegantula), and four species in the R. variegata group (R. flavinoda, R. gregaria, R. mutabilis and R. revolutionalis) are recognized in Australia, with a new synonymy of R. mutabilis torresiana Richards, 1978, under R. gregaria (de Saussure, 1854). Icaria torrida Smith, 1863, from Seram Island is synonymized with R. unicolor (Smith, 1859).  相似文献   

19.
By generalizing a previous paper on periodicities in the endocrine system (Bull. Math. Biophysics,30, 735–749, 1968), it is shown that nonperiodic, sporadic oscillations in the system are also possible. A procedure of describing the feedback mechanism between the endocrine system and the central nervous system is suggested. It is shown that the combined system: endocrine—CNS, also may show sporadic fluctuations.  相似文献   

20.
Purification of the HhaII Restriction Endonuclease from an Overproducer Escherichia coli Clone(Kelly, S., Kaddurah-Daouk, R., and Smith, H. O. (1985) J. Biol. Chem. 260, 15339–15344)Catalytic Properties of the HhaII Restriction Endonuclease(Kaddurah-Daouk, R., Cho, P., and Smith, H. O. (1985) J. Biol. Chem. 260, 15345–15351)Hamilton Othanel Smith was born in 1931 in New York City. In 1937, he and his family moved to Champaign-Urbana, Illinois, because his father had joined the faculty of the department of education at the University of Illinois. As a boy, Smith was interested in chemistry, electricity, and electronics, and he spent many hours with his brother in their basement laboratory, which was stocked with supplies purchased from their paper route earnings. Smith attended a small college preparatory school called the University Laboratory High School and graduated in 3 years largely due to his science teacher who allowed him to complete chemistry and physics during the summer.Open in a separate windowHamilton O. SmithAfter finishing high school, Smith enrolled at the University of Illinois, majoring in mathematics. During his sophomore year, his brother showed him a book on mathematical modeling of central nervous system circuits by Nicolas Rashevsky. This caught his interest, and after transferring to the University of California, Berkeley, Smith immersed himself in courses in cell physiology, biochemistry, and biology. A guest lecture by Journal of Biological Chemistry (JBC) Classic author George Wald (1) describing his studies of retinal biochemistry soon converted Smith into a devoted student of visual physiology and eventually motivated him to apply to medical school.In 1952, Smith began his studies at the Johns Hopkins University Medical School. He received his M.D. 4 years later and went to Barnes Hospital in St. Louis for a medical internship. However, in 1957, Smith was called up in the Doctor Draft and joined the U.S. Navy. He finished his Navy service in 1959 and moved to Detroit to begin a medical residency training at the Henry Ford Hospital. There he became interested in bacteriophage and decided that this would be the focus of his research.So, in 1962, Smith began his research career with Myron Levine in the department of human genetics at the University of Michigan in Ann Arbor. He and Levine carried out a series of studies demonstrating the sequential action of the phage P22 C-genes, which controlled lysogenization. They also discovered the gene controlling prophage attachment, now known as the int gene, and carried out a study of defective transducing particles formed after induction of int mutant prophage.In 1967, Smith joined the faculty of Johns Hopkins University as an assistant professor of microbiology and continued his bacteriophage research. A year later, working with Thomas J. Kelly, Jr. and Kent W. Wilcox, Smith isolated and characterized the first Type II restriction endonuclease (HindII) from Haemophilus influenzae and determined the sequence of its cleavage site (2, 3). In recognition of this discovery, he was awarded the 1978 Nobel Prize in Physiology or Medicine with Werner Arber and Daniel Nathans.These studies led to Smith''s subsequent research on DNA methylases and nucleases in H. influenzae. The two JBC Classics reprinted here detail Smith''s efforts to discover the rules governing sequence recognition in the Type II restriction endonuclease HhaII via x-ray crystallography. To facilitate these studies, Smith and his colleagues engineered a two-plasmid system in Escherichia coli that overproduced HhaII on induction with isopropylthiogalactoside (IPTG). The first paper describes the induction characteristics of the two-plasmid overproducer clone and purification of the endonuclease. The second paper, published back-to-back with the first, details the catalytic properties of the endonuclease. Smith used two methods to follow the reactions: 1) gel electrophoretic analysis of nicked circular and linear DNA products, and 2) release of 32P-labeled inorganic phosphate from specifically labeled HhaII sites in a reaction coupled with bacterial alkaline phosphatase. Smith''s two-plasmid system eventually allowed him to obtain crystals of the HhaII endonuclease with a heptanucleotide DNA duplex (4).Smith served on the faculty at Johns Hopkins for 30 years before retiring as American Cancer Society Distinguished Research Professor Emeritus of Molecular Biology and Genetics in 1998. In 1993, he accepted an appointment to the scientific advisory council of The Institute for Genomic Research, which led to his collaboration with J. Craig Venter in the sequencing of H. influenzae by whole genome shotgun sequencing and assembly. Five years later, Smith joined Celera Genomics, where he was senior director of DNA Resources and aided in the sequencing of the Drosophila and human genomes. In 2005, he co-founded Synthetic Genomics, an off-shoot of Celera. He also serves as scientific director of the Synthetic Biology & Biological Energy Groups at the J. Craig Venter Institute. In addition to the Nobel Prize, Smith has received several honors including election to the National Academy of Sciences in 1980.1  相似文献   

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