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1.
Haemorrhage is associated with intestinal mucosal hypoxia and impaired gut barrier function. Dopamine increases oxygen delivery to the intestinal mucosa and may thus counteract haemorrhage-induced mucosal hypoxia. Jejunal mucosal tissue oxygen tension (mucosal PO2) and jejunal oxygen saturation of mucosal microvascular haemoglobin (mucosal HbO2) were measured in 14 anaesthetized pigs. Seven animals served as controls (group C) and seven received continuous infusion of dopamine 16 micrograms kg-1 min-1 (group D) while 45% of blood volume was removed in three equal increments. Resuscitation was performed using shed blood and fluid. Mean arterial pressure and systemic oxygen delivery decreasing significantly during haemorrhage and returned to baseline after resuscitation in both groups. Mucosal PO2 decreased from 4.4 to 1.7 kPa after haemorrhage (P < 0.01) and further to 1.5 kPa after resuscitation (P < 0.01) in group C whereas group D showed an increase from 3.9 to 5.9 kPa after the start of the dopamine infusion (P < 0.05), but no significant difference from baseline after haemorrhage (2.3 kPa) (ns) or resuscitation (3.1 kPa) (ns). Mucosal HbO2 decreased from 52 to 32% after haemorrhage (P < 0.05) and increased to near baseline (37%) (ns) after resuscitation in group C whereas group D showed no significant changes from baseline (54%) throughout the experiment. Comparison between groups showed higher mucosal PO2 and HbO2 values for group D animals after the start of the dopamine infusion (P < 0.05 each), after the first two steps of haemorrhage (P < 0.01 each) and after resuscitation (P < 0.05 each). We conclude that i.v. dopamine 16 micrograms kg-1 min-1 improved tissue oxygenation of the small intestinal mucosa during moderate haemorrhage and subsequent resuscitation.  相似文献   
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We present a new synthetic approach leading to the formation of polypyrrole architectures in submicron level and to silver/polypyrrole nanocomposites via an interfacial polymerization in a water/chloroform interface. The oxidizing agent was either Ag(I) or Fe(III). In the first case, silver nanoparticles resulted. The mean diameter of the polypyrrole structures is in the range of 200-300 nm according to the addition or not of various surfactants. The progress of the reaction was studied by UV-visible spectroscopy, which also revealed the formation of a polaron band during the growth of the oligomers. The crystal structure of the polymers was examined by X ray diffractometry and all samples appeared to be amorphous, while the samples were further characterized by thermogravimetric analysis and FT-IR spectroscopy.  相似文献   
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Four types of cellulose, in particular carboxy methyl cellulose (CMC), are tested as potential binding materials in graphitic anodes for lithium ion batteries. It is shown that a minimum content of a cellulose which gives acceptable anode properties (reversible capacity>300 mA h g−1 during the first 10 cycles, irreversible loss<20%) is about 2 wt.%, which is less than in the case of conventional polymeric binders (5-10 wt.%). Kinetics of insertion-deinsertion and passivation processes seem not to be affected by the presence of cellulose. Explanation for the electrode failure at cellulose contents lower than 1 wt.% is given based on X-ray diffraction and microscopy investigations. Finally, the structure (distribution) of cellulose in the composite anode material is discussed and (indirectly) checked with a series of experiments. Most results are compared with the corresponding results obtained either with gelatin or conventional polymeric binders or both.  相似文献   
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Objective: The purpose of this study was to investigate and quantify flow properties, compressibility, and compactibility of various pharmaceutical lactose powders found on the market today (DCL-11, DCL-21, M‐200, Flowlac-100, and Tablettose 70, 80, and 100). Methods: Flow properties were estimated by measuring flow time, angle of repose, and the Hausner ratio. Particle rearrangement was studied using Kawakita's linear model. Compressibility was studied using two ‘out-of-die’ methods: (i) the Heckel model and (ii) a modified Walker model. Compactibility was quantified using two methods: (i) the tensile strength profile (Cp) and (ii) the compactibility factor (Pr). Statistical approach was used to analyze the results. Results: Flow properties of all materials were passable or better, except for M-200, which has very poor flowability. Compressibility results demonstrated that the most compressible lactose is spray-dried grade of lactose (Flowlac-100) and the least compressible is milled lactose (M-200). Compactibility studies showed that β‐lactose (DCL-21) forms tablets with superior tensile strength in comparison with α-lactose. Conclusion: Results of the compressibility study showed that the discriminative power of modified Walker model is greater in comparison with Heckel model. Compactibility methods yield similar and comparable results.  相似文献   
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DC‐SIGN, an antigen‐uptake receptor in dendritic cells (DCs), has a clear role in the immune response but, conversely, can also facilitate infection by providing entry of pathogens into DCs. The key action in both processes is internalization into acidic endosomes and lysosomes. Molecular probes that bind to DC‐SIGN could thus provide a useful tool to study internalization and constitute potential antagonists against pathogens. So far, only large molecules have been used to directly observe DC‐SIGN‐mediated internalization into DCs by fluorescence visualization. We designed and synthesized an appropriate small glycomimetic probe. Two particular properties of the probe were exploited: activation in a low‐pH environment and an aggregation‐induced spectral shift. Our results indicate that small glycomimetic molecules could compete with antigen/pathogen for binding not only outside but also inside the DC, thus preventing the harmful action of pathogens that are able to intrude into DCs, for example, HIV‐1.  相似文献   
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Zusammenfassung Der Bestand an Rotwild in Jugoslawien wird Ende 1957 auf ca. 15000 Stück geschätzt. Wegen der mannigfaltigen geschichtlichen, geographischen, ökologischen und genetischen Faktoren, die auf das Rotwild in den verschiedenen Gebieten einwirkten, ist das Rotwild Jugoslawiens hinsichtlich des Phäno- und Genotyps sehr verschiedenartig.Zur Zeit steht fast das ganze Rotwild nördlich der Linie, die von den Flüssen Donau-Sava-Una gebildet wird, obwohl es ehemals fast auf dem ganzen Gebiet Jugoslawiens vorkam.Das jugoslawische Rotwild ist teilweise autochthon, zum Teil stammt es von Rotwild ab, das aus verschiedenen europäischen Staaten nach Jugoslawien, größtenteils Ende des 19. und zu Beginn des 20. Jahrhunderts, eingeführt wurde. Im Südosten herrscht der maraloide, ansonsten jedoch der hypelaphoide Geweihtyp vor.Das Rotwild Jugoslawiens ist gut. Hirsche erreichen Gewichte von 350 kg, Tiere von 180 kg. Viele Trophäen haben Gewichte über 10 kg und Punktzahlen über 200 der internationalen Madrider Formel. Der bisher stärkste erlegte Hirsch erzielte 248,5 Punkte und war 1954 Champion auf der Internationalen Jagdausstellung in Düsseldorf.
Summary The number of red deer in Yugoslavia at the end of 1957 is estimated at approximately 15000 head. Because of widely differing historical, geographical, ecological and genetic factors, which have exercised, and are still exercising, their effect upon red deer in the various regions, this game differs in phenotype and genotype in Yugoslavia very much.At present almost all the red deer live north of the line formed by the rivers Danube, Sava, and Una, although in the past they were found practically throughout the whole of Yugoslavia.Yugoslav red deer are in part native to the country, and in part descended from red deer imported from various other European countries into Yugoslavia, mainly at the end 19th and the beginning of the 20th century. As regards type, the maraloid prevails towards the southeast, and the hypelaphoid type on the whole.Yugoslav red deer are an excellent breed. Many hunting trophies weight more than 20 lbs, and can claim more than 200 points according to the international Madrid formula. The most powerful stag shot so far was awarded 248,5 points and was the champion at the International Sportmen's (Hunters') Exhibition at Düsseldorf in 1954. The maximum weight attained by a stag is 350 kg (7 cwt.), and that of a hind 180 kg (3 1/2 cwt.).

Résumé Le nombre des cerfs en Yougoslavie à la fin de l'année 1957 était 15 000 envinon. En conséquence des influences très différentes des facteurs historiques, géyographique, écologique et génétiques, qui se manifestaient et se manifestent dans les diverses régions, sont les cerfs de la Yougoslavie différents de points de vue phéno et génotypique.Presque tous les cerfs vivent au Nord de la ligne tracée par les riviéres de Danube, Save et Une, bien qu'ils vivaient jadis sur le territoire presqu' entier de la Yougoslavie.Une partie des cerfs de Yougoslavie sont autochthones, l'autre tire son origine des cerfs, qui étaient importés en Yougoslavie d'autres pays Européens, par la plupart vers la fin du 19me et on début du 20m3 siecle. Comme types, c'est le type maraloide qui domine au Sud-Est, ailleurs c'est le type hypélaphoide.Les cerfs de Yougoslavie sont de bonne qualité. Bien de trophées atteignent plus de 10 kg du poidset plus de 200 points (formule internationale de Madrid). Le plus fort parmis les cerfs tirés était le champion de l'Exposition intérnationale de chasse à Düsseldorf en 1954 ayant reçu 248,5 points. Les cerfs atteignent au maximum 350 kg et les biches 180 kg du poids.
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The authors see interesting parallels between the development phases of physics (as a basic natural science), management/organization (as a science on orchestrating organizational parts for goal-focused leading and working in line with the law of requisite holism and resulting success), and systems theory (as a science on holism as a world view and methods to attain it) from determinism and division to realistic indeterminism by integration using information. Similar phases can be seen in Adam Smith's theory of economics. The authors suggest the introduction of the “Universal Dialectical Systems Theory” (UDST) as a common denominator of the values and methods of the requisitely holistic observation, perception, thinking, emotional and spiritual life, decision-making, and action by interdisciplinary creative co-operation and information, as a means to link natural and social sciences.  相似文献   
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Zusammenfassung Untersuchungen an 279 Häsinnen auf der Theiß-Insel Biserni otok in den Jahren 1954 und 1955 ergaben folgendes: Es wurden 5 Würfe festgestellt: 1. 10.–20. März; 2. 25.–30. April; 3. 1.–15. Juni; 4. 1.–15. August; 5. 12.–25. September.Der ideale Zuwachs je Häsin betrug 1954 10, 1955 7,8 Junge. Die meteorologischen Faktoren über nur einen geringen Einfluß auf den idealen Zuwachs aus. Beim 2. und 3. Wurf ist der Zuwachs am höchsten.Bemerkenswert ist, daß die Zahl der Gelbkörper oftmals nicht mit der Zahl der Fötusse übereinstimmt. Es fiel auf, daß das linke Horn der Gebärmutter öfter gravide ist als das rechte. Die Trächtigkeit sowie die Anzahl der Fötusse war nicht in einer Abhängigkeit von der Größe oder dem Gewicht, der Häsin. Bei 61 Fötussen, die 32 Häsinnen innehatten, waren 32 und 29 .
Summary The examination of 279 female hares in the Tissa-Island Biserni otok had the following results: 5 litters were constatated. 1. March 10–20th; 2. April 25th–30th; 3. June 1st–15th; 4. August 1st–15th; 5. September 12th–25th.The ideal increase for every female hare amounted to 10 youngs in 1954, to 7.8 young ones in 1955. Meteorological factors have only little influence upon the ideal increase. Increase ist highest in number in the second and third litter.It is remarkable that the number of luteocorpuscles is often not identical with the number of foetus. It was noticed that the left horn of the uterus is more frequently gravid than the right one. The pregnancy and the number of foetus did not depend on size or weight of the femalc hares. Of 61 foeti in 32 hares 32 were female and 29 male.

Résumé Après les recherches qu'on a fait pendant les années 1954 et 1955 sur 279 lièvres dans l'isle Biserni otok dans la Tissa, on vient de trouver les résultats suivants: 5 portées furent constatées 1e) 10–20 Mars; 2e) 25–30 Avril.; 3e) 1–15 Juin; 4e) 1–15 Août; 5e) 12–25 Septembre.Le surcroît idéal par lièvre était en 1954 10, en 1955 7,8 petits. Sur ce surcroît idéal les facteurs météorologiques n'exercent qu'une influence peu considérable. Le plus grand surcroît fut constaté chez la deuxième et troisième portée. Il est à remarquer que le nombre des corps jaunes ne correspondent souvent pas avec le nombre des ftus.Il frappait que la corne gauche de l'utérus était plus souvent gravide que la corne droite. La gestation anisi que le nombre des ftus ne dépendait pas de la taille ni du poids de la lièvre. Chez 61 ftus trouvés sur 32 lièvres 32 étaient et 29 .
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