Search Results - (Author, Cooperation:J. F. Thompson)

2013-06-28

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Conservation of Natural Resources ; DNA/analysis/genetics ; Endangered Species ; Equidae/classification/genetics ; *Evolution, Molecular ; Fossils ; Genetic Variation/genetics ; Genome/*genetics ; History, Ancient ; Horses/classification/*genetics ; *Phylogeny ; Proteins/analysis/chemistry/genetics ; Yukon Territory

2018-07-03

The American Association for Cancer Research (AACR)

1078-0432

1557-3265

Medicine

1365-2044

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Allergy to latex products has become a problem of increasing dimensions, affecting both patients and health-care professionals. Certain high-risk groups and sources of latex exposure have been identified. The clinical manifestations vary from contact eczema through a range of allergic syndromes including life-threatening anaphylaxis. An understanding of the clinical and immunological features of latex allergy provides the basis of therapeutic and preventive strategies. Latex allergy is also becoming a major occupational health issue.

Electronic Resource

1365-2044

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Noise in the operating theatre, recovery room and intensive care unit is above internationally recommended levels. The psychological and physiological effects of noise are reviewed. Equipment and conversation among the staff are major sources of noise in these areas. Equipment design, modification of nursing care procedures, and increased awareness of noise created by the staff may be effective in reducing noise pollution in these areas.

Electronic Resource

1365-2133

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1750-3841

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Process Engineering, Biotechnology, Nutrition Technology

Electronic Resource

1365-2559

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Although tumour thickness is the best predictor of melanoma prognosis in patients with localized cutaneous melanoma, prolonged survival occasionally occurs in patients with thick melanomas (〉 5 mm). This study examined histological features which were associated with long-term survival.〈section xml:id="abs1-2"〉〈title type="main"〉Methods and resultsForty-two patients with thick, vertical growth phase melanomas surviving 10 years or more after diagnosis were matched by clinical stage of disease, sex, age and anatomical site of the primary lesion with 42 patients with similar characteristics who died from their disease within 3 years of diagnosis. Fourteen histological factors were assessed in both groups. Tumours with spindle cell and Spitz-like cell populations and those with low mitotic activity were significantly more frequently observed in long-term survivors. There was also a significant excess of melanomas exhibiting desmoplasia and those lacking vascular invasion in the long-term survivors.〈section xml:id="abs1-3"〉〈title type="main"〉ConclusionsThese findings suggest that it may be useful to modify the current cutaneous melanoma classification on the basis of unusual cytological characteristics (as discussed at the recent 4th World Conference on Melanoma).

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] THROUGH the courtesy of Drs. Leach and Lindley, we have seen their communication on the structure of asparagine, prior to its publication. This and numerous other comments that we have received testify to the interest which our article1 aroused. In that sense, part of our purpose was achieved, ...

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] Through the courtesy of Drs. Sondheimer and Holley, we have seen their paper3 and communication (above) on L-amino-succinimide in advance of their publication. They are to be congratulated on what appears to be an elegant piece of synthetic work leading to derivatives of L-amino-succinimide and to ...

Electronic Resource

1365-2559

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

We attempted to clarify the prevailing controversy regarding the significance of regression in thin (〈0.76 mm) primary melanomas. Of 7540 patients with cutaneous melanomas treated at the Sydney Melanoma Unit, 28 first presented with a thin primary lesion and concurrent regional lymph node metastases (stage II). Major differences in tumour histology existed between these patients and stage I patients with thin lesions that subsequently recurred. Regression was present in all 28 lesions in stage II patients. In 61 stage I patients ultimately developing a recurrence, 67% of lesions displayed regression. Significantly, however, in 735 stage I patients ultimately not developing a recurrence, 61% of lesions also displayed regression. Why regression occurs so frequently in thin lesions which never recur is unclear. Our results suggest that the histology of thin primary melanomas may be influenced by the presence or absence of metastases in patients at that time.

Electronic Resource

1432-1866

Springer Online Journal Archives 1860-2000

Geosciences

Abstract An under-recognized and economically important class of intrusion-related gold deposits, which occur within magmatic provinces best known for tungsten and/or tin mineralization, is described with reference to seven major deposits (Fort Knox, Mokrsko, Salave, Vasilkovskoe, Timbarra, Kidston and Kori Kollo). These gold deposits contain a metal suite that includes some combination of bismuth, tungsten, arsenic, tin, molybdenum, tellurium and antimony, and contrasts with that found in the more widely-developed gold-rich porphyry copper and related deposits. The gold deposits associated with tungsten and/or tin provinces are located in cratonic margins, in a landward or back-arc position relative to continental margin arcs (where recognized), or within continental collisional settings. The deposits are related genetically to felsic domes, stocks or plutons of intermediate oxidation state, both magnetite- and ilmenite-series magmas are represented. The intrusion-hosted gold deposits are most commonly of sheeted vein/veinlet type, although greisen-like, disseminated and breccia deposits are also described. Gold may also be concentrated more distally (1–3 km) with respect to the intrusions, where deposits may be of skarn, disseminated replacement or vein types. K-feldspar, albite and/or sericitic alteration assemblages, commonly including carbonate, accompany the gold mineralization. In sheeted vein deposits, alteration is normally restricted to narrow envelopes around veins, whereas more pervasive alteration occurs in greisen-like, disseminated and shallow (〈3 km) deposits. The gold mineralization is commonly present with low total sulphide contents (〈3%), mainly pyrite and lesser arsenopyrite. In several deposits, bismuth minerals are closely associated with gold, and bismuth-gold and tellurium-gold correlations exist. Most deposits contain tungsten, tin, molybdenum and antimony, although generally these do not correlate with gold; tungsten and molybdenum concentrations may increase with depth or may occur in separate zones. Base metals generally are present in minor amounts (e.g. 〈100 ppm Cu). The distinct spatial association with felsic intrusions, combined with the consistent metal signature, suggests a magmatic-hydrothermal origin. Fluid inclusions studies indicate the presence of high-salinity fluids in some deposits, and low-salinity and carbonic fluids in most deposits, similar to the composition of fluids in intrusion-related tungsten deposits. Variations in mineralization style largely reflect depth of formation and location relative to the intrusive centre. Several deposits in this class contain 〉100 tonnes (3 million oz) of gold, thereby highlighting the gold potential of intrusion-related deposits beyond the more traditionally explored gold and copper provinces in arc terranes.

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] CONCERNING the old, but still challenging, problem of the first product of photosynthesis and the subsequent path toward sugar, two different groups of workers have recently reached different conclusions. The active California group, led by Calvin and Benson1*2'3, conclude that the immediate ...

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] The Etnean lavas from major eruptions during the past 400 yr are well known, the most famous being the 1669 flow that buried about 15 villages and part of the town of Catania. Contrary to popular belief, however, older eruptions are far .from being accurately described7'8. Between AD 1600 and 1300, ...

Electronic Resource

1432-1106

Key words Movement ; Basal ganglia ; Striatum ; Reaction time ; Sensory cues

Springer Online Journal Archives 1860-2000

Medicine

Abstract  We examined the changes in learned and spontaneous motor behavior after a unilateral excitotoxin lesion of the neostriatum. Cats were trained to perform a sensory-cued GO/NO-GO reaching task. Success rate, reaction time, movement speed and kinematic patterns were used to characterize motor system properties. In addition, motor properties before and after the lesion were compared by clinical neurological examinations and video tape observations of free-range behavior. We found that in normal animals motor performance in the task was fluent, highly automatic and skillful with consistent patterns from trial to trial and day to day. The striatal lesion resulted in a marked impairment in the animals’ ability to perform the automatic response to the sensory cues in the motor task. In contrast, sensorimotor behavior in contexts apart from the task was altered minimally, with changes that were often difficult to detect. The animals recovered their ability to perform the task gradually, although they never reached prelesion performance levels in up to 24 weeks of evaluation. The animals had difficulty making reaching movements in GO trials and, in NO-GO trials failures to withhold movements were more frequent. Failures were due to a specific inability to execute previously well-learned movements in response to cues and not to an inability to recognize and interpret the cues. The lesion effects were restricted to the automatic motor response to the learned cues, as the animals could make reaching movements to the target without obvious impairment in response to novel stimuli. They also made similar spontaneous movements apart from the motor task that appeared to be unimpaired. The unique motor style and strategies that characterized the behavior of individual animals prior to the lesion were still evident after the lesion, even though they were superimposed on lower success rates and slower movement speeds. Our findings suggest that the basal ganglia facilitate the fluent and rapid execution of sequences of well-learned sensorimotor behavior, but the representations of motor plans are not stored in the basal ganglia.

Electronic Resource

1432-1866

Springer Online Journal Archives 1860-2000

Geosciences

Abstract Zones of advanced argillic alteration constituting lithocaps are commonplace in the shallow parts of porphyry copper systems. Similar lithocaps are also recognized in the shallowly eroded southern part of the Bolivian tin-silver belt, where mineralization typically is centred on felsic volcanic domes. A well-preserved lithocap at Potosí is dominated by vuggy residual quartz and contained the world's largest silver resource, whereas the basal remnant of a lithocap at Pulacayo is composed of barren quartz-alunite. Minor gold occurs in the structurally controlled roots of a lithocap at Tasna. The mineralization in these lithocaps is of high-sulphidation type and was generated in the epithermal environment. In contrast, the tin- and base metal-bearing massive sulphide veins and associated sericitic and quartz-tourmaline alteration that underlie the Bolivian lithocaps are typified by sulphides of low sulphidation state, but are dominantly mesothermal rather than epithermal in character. Magma chemistry is believed to account for the characterization of Bolivian lithocaps by silver-tin-antimony and porphyry copper lithocaps by gold-copper-arsenic. Low-grade, bulk-tonnage silver mineralization within Bolivian lithocaps and high-grade tin-bearing veins concealed beneath them both constitute attractive exploration objectives.

Electronic Resource

1573-9104

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Zusammenfassung Brassica rapa var.Shogoin — als „turnip greens“ in den Südstaaten der USA wie ein Gemüse verzehrt — wurde in Gefäßversuchen unter normalen und unter Mangelbedingungen (Stickstoff-, Phosphorsäure-, Schwefel-, Kalium-, Calzium- oder Magnesium-Mangel) kultiviert. In der Pflanzensubstanz wurden die nicht gebundenen Aminosäuren von der Eiweißfraktion abgetrennt. Die Eiweißfraktion der Blätter wurde auf ihre Aminosäuregarnitur untersucht. Es wurden beträchtliche Unterschiede im Eiweißhaushalt der Blätter von Mangelreihen und normalen gefunden, jedoch war die relative Zusammensetzung der Eiweißfraktion von dieser Veränderung nur wenig betroffen. Die nicht eiweißgebundenen Aminosäuren wurden dagegen weitgehend durch die Mineralstoffversorgung der Pflanze beeinflußt. Die Unterschiede in der Aminosäurekonzentration lassen erkennen, daß die Abwesenheit der verschiedenen Makronährstoffe den Aminosäurestoffwechsel in mannigfacher Weise verändert.

Résumé Brassica rapa var.Shogoin — bien connue aux Etats-Unis comme légume — était cultivée dans les pots d'expérience sous des conditions normales et des conditions de carence en Azote, en Acide phosphorique, en Sulfure, en Potasse, en Calcium ou en Magnesium. Dans les matières fraîches les acides aminés libres étaient isolés de la fraction de Protéines. La fraction de Protéines des feuilles était analysée en ce qui concerne les acides aminés. On a trouvé des différences considérables dans le contenu de Protéines des plantes cultivées aussi bien dans les conditions normales que dans les conditions de carence. La composition relative de la fraction de Protéines n'ðait que peu effectuées par ces différentes conditions. Les acides aminés libres étaient par contre influencés considérablement par les engrais minéraux fournis aux plantes. Les différences de concentration des acides aminés montrent que l'absence des différents macroéléments change le métabolisme des acides aminés d'une façon diverse.

Summary Turnip plants have been grown under conditions of normal mineral nutrition and with deficiencies of nitrogen, phosphorus, sulfur, potassium, calcium or magnesium. The uncombined amino acids were separated from the protein fraction. The protein fraction of the leaves was analyzed for constituent amino acids. It was found that there were considerable differences in protein level between deficient and normal leaves but that the relative composition of the protein fraction was only slightly affected. The non-protein amino acids were profoundly influenced by mineral nutrition. The differences in amino acid concentrations suggested that the lack of various macronutrients affected the metabolism of amino acids in many ways.

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