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1.
A novel experimental method was developed which allows the determination of the threshold concentration of sucrose by use of a linear sucrose gradient in water. With this method a continuous tasting of the test-liquid is possible. A panel of 15 persons experienced in taste-testing was used. Three gradients of different steepness were applied: 0 to 1.5% (w/w) sucrose in 2 min (I), 3 min (II) and 4 min (III). The results of the new method were compared with those of the standard method (DIN). With gradients I and II we found values which were significantly higher than those of the standard method (I: 0.49% (w/w); II: 0.46% (w/w); DIN: 0.31% (w/w)), whereas with gradient III the same threshold value was found as with the DIN-Method (III: 0.32% (w/w)).  相似文献   
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Background  

The aim of this study was to evaluate long-term platinum retention in patients treated with cisplatin and oxaliplatin.  相似文献   
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The compulsory dispute settlement regime included in the 1982 Law of the Sea Convention is recognized as one of the most comprehensive in a modern international convention. Yet, in the recent application of this regime, the question has arisen as to whether the procedural prerequisites associated with the LOS Convention's compulsory dispute settlement mechanism are so arduous as to avoid binding and compulsory jurisdiction in most instances. This article addresses that question by examining, in particular, the reasoning of the Southern Bluefin Tuna arbitration tribunal, which found Article 281 of Section 1 of the LOS Convention to bar jurisdiction to the compulsory dispute settlement mechanism prescribed by the Convention, and offers suggestions as to how states might distinguish or overcome the barriers imposed by the Southern Bluefin Tuna tribunal in future cases.  相似文献   
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The synthesis of the new radioprotective compounds ATB (I, 2-allylthioureidobenzoic acid), PTB (II, 2-phenylthioureidobenzoic acid), A-2-PTU (III, N-allyl-N"-2-pyridylthiourea), and P-2-PTU (IV, N-phenyl-N"-2-pyridylthiourea) and their influence on biological and genetic effects of gamma rays was studied. In result of investigations it must be noted that PTB displayed radioprotective effect as a result of which more plants in M1 germination and survive in M2 of the induced mutations is increased. The cytological analysis reveals that the studied substance (PTB) decreases chromosome aberration in meristem cells of pea roots almost twice as a result of postirradiation treatment. The effect of A-2-PTU in the experiments with peas greatly depends on the dose of irradiation, i.e., on the degree of damaging of the processes of cell restoration and the possibility of their partial restoration after the treatment with the protector. The results obtained suggest that chemical compounds of N,N"-disubstituted thiourea group (A-2-PTU and P-2-PTU) exert strong radioprotective effect in the experiments with peas. This is of great importance to modern radiobiology and radiation mutagenesis and also to protect hereditary structures against radiation.  相似文献   
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The review presents our research on the influence of novel thiourea compounds on the biological and genetic effect of gamma-rays using in vivo and in vitro systems of pea. Some novel disubstituted thioureas: o-allylthioureidobenzoic acid (ATB); o-phenylthioureidobenzoic acid (PTB); N-allyl-N'-2-pyridylthiourea (A-2-PTU); N-phenyl-N'-2-pyridylthiourea (P-2-PTU) and 1,4-allylthioureidosalicylic acid (ATUS) were examined. Pea (Pisum sativum L.) seeds from five varieties were used. Experiments in vivo and in vitro were carried under laboratory, greenhouse and field conditions. The data revealed the PTB radioprotective effect demonstrated by: reduction of chromosome aberrations by 2 folds; 50% increase of germinating and surviving plants in M1; twice higher frequency of induced mutations in M2 generation relative to irradiation without PTB treatment; decreasing the level of induced radiation suppression leading to favorable effect on the initial stem and root development of pea. ATB radioprotective effect was demonstrated in vitro by: 25-35% stimulation of organogenesis; by 20-50% increase in bud formation; by 25% stimulation of growth. The effect of A-2-PTU and P-2-PTU depended on the irradiation dose. The protective effect of A-2-PTU is more pronounced at lower irradiation dose, while the effect of P-2-PTU is more pronounced at higher irradiation dose. ATUS, opposite to the other compounds, revealed radiosensibilizing effect by: 16-27% increase in lethality caused by gamma-rays leading to lower number of germinating and surviving plants in M1; 50% decrease in the number of induced mutations in M2 generation; limiting the types of induced mutations at the higher irradiation dose. As a result of the experiments useful mutation forms were obtained, characterized with: earliness, lodging and disease resistance; higher productivity.  相似文献   
6.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
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1. Availability of suitable habitat is a prerequisite for species reintroduction success, and to ensure population persistence, investigations of a species’ habitat utilisation throughout its life history should be conducted as part of a feasibility study. 2. Habitat utilisation models for burbot, Lota lota, developed using data from field studies conducted in France and Germany and information from the literature were used to assess the feasibility of reintroducing burbot into rivers of its former native range in eastern England. 3. Per cent tree roots, aquatic vegetation and flow types were important predictors of adult burbot abundance. Furthermore, the habitat utilisation models were supplemented with information from the literature, which suggested that off‐channel habitat such as wetlands and backwaters is important for spawning and nursery stages. 4. An assessment of the habitat availability in the rivers of the burbot’s former native range using variables related to spawning and nursery and adult life stages showed that although adult habitat was widely distributed, the availability of spawning and nursery habitat was less abundant, potentially limiting successful reestablishment. 5. Potential suitable habitat was concentrated in the central and southern areas of the species’ former English distribution. Overall, rivers of the burbot’s former range potentially afford suitable habitat to sustain a reintroduced population. However, sites should be preferentially selected on the basis of having appropriate spawning and nursery areas.  相似文献   
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