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21.
Effects of destabilise, bdellin, bdellin A, eglin were investigated in organotypic tissue culture of dorsal root ganglia (DRG) of 10-11-day old chick embryos. Native destabilase and bdellin A, bdellin B and eglin are more active inducing a more intensive neurite growth in DRG as compared with the control. A neurite-stimulating effect of the drug "pyjavit" seems to be associated with destabilase, bdellins and eglin neurite-stimulating activity.  相似文献   
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It is demonstrated that the method of immobilization of human plasmin by its adsorption on L-lysine-Sepharose 4B can be successfully applied for bovine plasmin isolation. Proteolysis of bovine prothrombin by bovine prothrombin by bovine plasmin preparations of high caseinolytic activity results in the increase of prothrombin level. Prothrombin proteolysis by bovine plasmin preparations of high caseinolytic activity results in the decrease of prothrombin level.  相似文献   
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Changes in plasmalemma K+Mg2+-ATPase dephosphorylating activity and H+ transport were examined in freezing-tolerant and non-tolerant genotypes of the perennial grass species Festuca pratensis Huds. Enzyme activity and ΔμH+ were measured in plasmalemma fractions isolated from basal nodes and roots. Three types of experiments were undertaken: (i) a field experiment, utilizing the seasonal growth and cessation cycle of a perennial plant; (ii) a cold acclimation experiment in hydroponics; and (iii) an instant freezing test. A specific fluctuation in K+Mg2+-ATPase activity was found throughout the seasonal growth of the plants (i). The K+Mg2+-ATPase activity peaks for both the basal node and the root plasmalemma were determined early in the spring before the renewal of growth. The lowest activity values in roots occurred at the time approaching flowering, and in basal nodes at the transition into the growth cessation. The K+Mg2+-ATPase activity was approximately 50% lower in the basal node plasmalemma of freezing-tolerant plants than of non-tolerant ones, when assessed at the optimal growth stage in hydroponics. In hydroponics (ii) and in the freezing test (iii), temperature stress was followed by a more pronounced change in the level of K+Mg2+-ATPase activity than in that of H+ transport, and this change was more clearly differentiated in the basal node plasmalemma of contrasting genotypes than in the roots. Stress response was manifested differently in freezing-tolerant and non-tolerant plants at cold acclimation (4–2 °C) and at freezing (−8 °C) temperatures. Proton transport regulation via coupled changes in the hydrolysed ATP/transported proton ratio, as an attribute of freezing-tolerant plants, is discussed.  相似文献   
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The state of the arterial wall in elderly patients after the application of medicinal leech was analyzed using an Angioscan-01 diagnostic device. The effect of one medicinal leech on the endothelial vasomotor function of small resistance arteries and medium-sized muscular arteries was estimated. Arterial wall rigidity was assessed by measuring the arterial stiffness index and the augmentation index during stress testing in the form of brachial artery occlusion. It has been shown that the application of one medicinal leech has not only local, but also system effect on arterial endothelium by improving its vasomotor function through normalization of arterial wall stiffness. This process is supposed to involve the salivary cell secretion of medicinal leech, which is able to raise the NO level both in cells and in extracellular fluid and to activate e-NOS and n-NOS, as it has been shown recently in the culture of human vascular endothelial cells (HUVEC).  相似文献   
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It is firstly showed that the medicinal leech salivary gland secretion (SGS) as a polycomponent system of proteins and low-molecular weight substances, activates rat subcutaneous mast cells in vitro prompting a decrease in the heparin saturation index and increasing some characteristic mast cells morphometric parameters. The same mast cell changes were detected by analysis of some specimens of subcutaneous cellular tissue in the point of skin injured by the leech bite. It is shown that these changes are saved during 3 days. The mechanical injury of rat skin does not effect the mast cells activation. Activation of mast cells by SGS is extended to the distant subcutaneous mast cells. It is expressed in sharp decreasing of heparin saturation index although not statistically positive. The secondary leeching on these distant points provokes reduction of mast cells activation and some decrease of post-leeching blood heparin content: 0.154 +/- 0.03 units/ml (n = 10) as compared with post-leeching blood heparin contents analysed from the wound after the primary leeching (0.160 +/- 0.03 units/ml, n = 10). Proceeding from these findings, participation of heparin secreted from activated mast cells in the support of post-leeching bleeding is suggested, the phenomenon which provides unloading of capillary pool by application of medicinal leeches for treatment many diseases.  相似文献   
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The genomes of grasses and cereals include a diverse and large collection of selfish genetic elements, many of which are fossil relics of ancient origin. Some of these elements are active and, because of their selfish nature and the way in which they exist to perpetuate themselves, they cause a conflict for genomes both within and between species in hybrids and allopolyploids. The conflict arises from how the various elements may undergo 'drive', through transposition, centromere and neocentromere drive, and in mitotic and meiotic drive processes in supernumerary B chromosomes. Experimental and newly formed hybrids and polyploids, where new combinations of genomes are brought together for the first time, find themselves sharing a common nuclear and cytoplasmic environment, and they can respond with varying degrees of instability to adjust to their new partnerships. B chromosomes are harmful to fertility and to the physiology of the cells and plants that carry them. In this review we take a broad view of genome conflict, drawing together aspects arising from a range of genetic elements that have not hitherto been considered in their entirety, and we find some common themes linking these various elements in their activities.  相似文献   
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The potential impact of new invasive tree pests and diseases is usually quantified in economic terms. The ecological and social impacts are less often assessed. Using a comprehensive literature review we assess the potential ecological and social impact of two non-native invasive species (the box tree moth, Cydalima perspectalis and the fungus Calonectria pseudonaviculata) that threaten the survival of box tree, Buxus spp. in forests in Europe and the Caucasus. A total of 132 fungi, 12 chromista (algae), 98 invertebrate and 44 lichens were found to use Buxus spp. Of these, 43 fungi, 3 chromista and 18 invertebrate species have only been recorded on Buxus spp., suggesting that these species are obligate on Buxus spp. and are most at risk from in the loss of Buxus spp. due to these invasive pest and disease species. Buxus spp. was shown to be important for soil stability and water quality but there was no information on other ecosystem functions provided by Buxus spp. Buxus was found to be of considerable historical cultural importance but there was very limited information on current social values and uses. Buxus trees, wood and leaves are associated with different folklore and sacred rites which are still particularly important in the Caucasus. While we could not find any assessment of the economic value of Buxus forests the biodiversity, cultural and social values of Buxus identified here indicate that its loss could have major indirect and non-market economic effects. This work highlights the importance of studying the ecological and societal implications of biological invasions.  相似文献   
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