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1.
Linkage analysis was performed in a family with nonspecific X-linked mental retardation (MRX). Affected individuals had no clinical characteristics other than mental retardation. Linkage was detected to the marker loci DXS477, DXS465, DXS52, DXS15 and F8C with maximum lod scores of 1.70, 1.32, 2.52, 1.70, and 1.09, respectively ( = 0.0). The results strongly indicate that the gene for mental retardation in the family studied maps close to DXS52. 相似文献
2.
The borohydride-reducible compounds of human aortic elastin. Demonstration of a new cyclic amino acid in alkali hydrolysate, and changes with age and in patients with annulo-aortic ectasia including one with Marfan syndrome. 总被引:2,自引:2,他引:0
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T Halme M Jutila T Vihersaari P Oksman N D Light R Penttinen 《The Biochemical journal》1985,232(1):169-175
Chronic (10-day) diabetes was associated with increased metabolic flux through phenylalanine hydroxylase in isolated liver cells. This flux was stimulated by 0.1 microM-glucagon, but not by 10 microM-noradrenaline; 0.1 microM-insulin affected neither basal nor glucagon-stimulated flux. The increased rate of phenylalanine hydroxylation in diabetes was accompanied by parallel increases in enzyme activity (as measured with artificial cofactor) and immunoreactive-enzyme-protein content. In contrast with total protein synthesis, which decreased, phenylalanine hydroxylase synthesis persisted at the control rate in cells from diabetic animals. These findings are discussed in relation to the hormonal regulation of the hydroxylase and the known metabolic consequences of chronic diabetes. 相似文献
3.
In fasting Pisidium amnicum and Sphaerium corneum, regular periods of behavioural and metabolic quiescence were shown to occur in the normoxic, constant environment of the flow-through chamber of a heat-flow microcalorimeter. The metabolic rate was suppressed to 7.5% of normal at 10° C and to 8.5–9.7% at 20° C for periods exceeding the period of active metabolism by a factor of 3.5 at 10° C and 8.3 at 20° C. The rate of heat output during normoxic quiescence was equal to that during environmental anoxia, suggesting spontaneous achievement of body anoxia by complete shell closure. The mass-specific integrated heat output during closure periods was independent of size. Parallel observations on clam behaviour suggested that metabolic quiescence coincided with shell closure, and bursts of heat flow with active ventilation. Shell closure was accompanied by pronounced bradycardia, down to 20% of the active rate. In a constant environment, the rhythmic quiescence is regulated by shell closure which is probably triggered by lack of food. Regular quiescence of fasting bivalves may conserve energy reserves considerably, the amount depending on the possible excretion rate of the end products, and the post-quiescence recovery costs, which were not measured. Heat output during the active period was close to the average metabolic rate found earlier for Sphaeriidae. However, all the values determined so far are likely to be underestimates of the natural metabolism because the effects of digestion and growth are not included. 相似文献
4.
Hannu K. Penttinen 《Analytical biochemistry》1980,102(2):353-357
A sensitive and accurate method for the determination of inorganic phosphate is described. The method enables the estimation of 10 nanomoles of inorganic phosphate with a coefficient of variation of 3.6% for ten replicates. The method is suitable for the estimation of the activities of thiamine triphosphatase, adenosine triphosphatase, and alkaline and acid phosphatase by a continuous flow system. 相似文献
5.
Belogurov GA Turkina MV Penttinen A Huopalahti S Baykov AA Lahti R 《The Journal of biological chemistry》2002,277(25):22209-22214
H(+)-translocating pyrophosphatase (H(+)-PPase) of the photosynthetic bacterium Rhodospirillum rubrum was expressed in Escherichia coli C43(DE3) cells. Recombinant H(+)-PPase was observed in inner membrane vesicles, where it catalyzed both PP(i) hydrolysis coupled with H(+) transport into the vesicles and PP(i) synthesis. The hydrolytic activity of H(+)-PPase in E. coli vesicles was eight times greater than that in R. rubrum chromatophores but exhibited similar sensitivity to the H(+)-PPase inhibitor, aminomethylenediphosphonate, and insensitivity to the soluble PPase inhibitor, fluoride. Using this expression system, we showed that substitution of Cys(185), Cys(222), or Cys(573) with aliphatic residues had no effect on the activity of H(+)-PPase but decreased its sensitivity to the sulfhydryl modifying reagent, mersalyl. H(+)-PPase lacking all three Cys residues was completely resistant to the effects of mersalyl. Mg(2+) and MgPP(i) protected Cys(185) and Cys(573) from modification by this agent but not Cys(222). Phylogenetic analyses of 23 nonredundant H(+)-PPase sequences led to classification into two subfamilies. One subfamily invariably contains Cys(222) and includes all known K(+)-independent H(+)-PPases, whereas the other incorporates a conserved Cys(573) but lacks Cys(222) and includes all known K(+)-dependent H(+)-PPases. These data suggest a specific link between the incidence of Cys at positions 222 and 573 and the K(+) dependence of H(+)-PPase. 相似文献
6.
Cox point process is a process class for hierarchical modelling of systems of non-interacting points in Rd under environmental heterogeneity which is modelled through a random intensity function. In this work a class of Cox processes is suggested where the random intensity is generated by a random closed set. Such heterogeneity appears for example in forestry where silvicultural treatments like harvesting and site-preparation create geometrical patterns for tree density variation in two different phases. In this paper the second order property, important both in data analysis and in the context of spatial sampling, is derived. The usefulness of the random set generated Cox process is highly increased, if for each point it is observed whether it is included in the random set or not. This additional information is easy and economical to obtain in many cases and is hence of practical value; it leads to marks for the points. The resulting random set marked Cox process is a marked point process where the marks are intensity-dependent. The problem with set-marking is that the marks are not a representative sample from the random set. This paper derives the second order property of the random set marked Cox process and suggests a practical estimation method for area fraction and covariance of the random set and for the point densities within and outside the random set. A simulated example and a forestry example are given. 相似文献
7.
Predation risk and feeding patterns of crucian carp 总被引:1,自引:0,他引:1
C. A. Paszkowski O.-P. Penttinen † I. J. Holopainen † W. M. Tonn 《Journal of fish biology》1996,48(5):818-828
As part of an experimental study of the direct and indirect effects of piscivory on prey fish, the diets of crucian carp Carassius carassius were compared across sections of a divided pond; two sections were stocked with crucian carp alone and two with crucian carp plus perch Perca fluviatilis . Analysis of crucian gut contents indicated that the composition of invertebrate prey did not differ in the presence v . absence of perch. However, crucians, particularly small individuals (<10cm) that were most vulnerable to predation, displayed a lower intake of invertebrate prey in sections with perch. Although diet composition differed between crucians caught in inshore v. offshore habitats (with habitat use being related to crucian size and the presence or absence of perch), no clear pattern existed between habitat and total food intake. Overall, the major effects of predators on the diet of crucian carp appeared to be caused by increased ecological density (resulting from confinement of small crucians inshore) and reduced activity levels, rather than simple shifts to safer habitats. 相似文献
8.
Knowledge about large-scale and long-term dynamics of (natural) populations is required to assess the efficiency of control
strategies, the potential for long-term persistence, and the adaptability to global changes such as habitat fragmentation
and global warming. For most natural populations, such as pest populations, large-scale and long-term surveys cannot be carried
out at a high resolution. For instance, for population dynamics characterized by irregular abundance explosions, i.e., outbreaks,
it is common to report detected outbreaks rather than measuring the population density at every location and time event. Here,
we propose a mechanical-statistical model for analyzing such outbreak occurrence data and making inference about population
dynamics. This spatio-temporal model contains the main mechanisms of the dynamics and describes the observation process. This
construction enables us to account for the discrepancy between the phenomenon scale and the sampling scale. We propose the
Bayesian method to estimate model parameters, pest densities and hidden factors, i.e., variables involved in the dynamics
but not observed. The model was specified and used to learn about the dynamics of the European pine sawfly (Neodiprion sertifer Geoffr., an insect causing major defoliation of pines in northern Europe) based on Finnish sawfly data covering the years
1961–1990. In this application, a dynamical Beverton–Holt model including a hidden regime variable was incorporated into the
model to deal with large variations in the population densities. Our results gave support to the idea that pine sawfly dynamics
should be studied as metapopulations with alternative equilibria. The results confirmed the importance of extreme minimum
winter temperatures for the occurrence of European pine sawfly outbreaks. The strong positive connection between the ratio
of lake area over total area and outbreaks was quantified for the first time. 相似文献
9.
The Diversity and Anti-Microbial Activity of Endophytic Actinomycetes Isolated from Medicinal Plants in Panxi Plateau,China 总被引:1,自引:0,他引:1
Ke Zhao Petri Penttinen Tongwei Guan Jing Xiao Qiang Chen Jun Xu Kristina Lindström Lili Zhang Xiaoping Zhang Gary A. Strobel 《Current microbiology》2011,62(1):182-190
Traditional Chinese medicinal plants are sources of biologically active compounds, providing raw material for pharmaceutical,
cosmetic and fragrance industries. The endophytes of medicinal plants participate in biochemical pathways and produce analogous
or novel bioactive compounds. Panxi plateau in South-west Sichuan in China with its unique geographical and climatological
characteristics is a habitat of a great variety of medicinal plants. In this study, 560 endophytic actinomycetes were isolated
from 26 medicinal plant species in Panxi plateau. 60 isolates were selected for 16S rDNA-RFLP analysis and 14 representative
strains were chosen for 16S rDNA sequencing. According to the phylogenetic analysis, seven isolates were Streptomyces sp., while the remainder belonged to genera Micromonospora, Oerskovia, Nonomuraea, Promicromonospora and Rhodococcus. Antimicrobial activity analysis combined with the results of amplifying genes coding for polyketide synthetase (PKS-I, PKS-II)
and nonribosomal peptide synthetase (NRPS) showed that endophytic actinomycetes isolated from medicinal plants in Panxi plateau
had broad-spectrum antimicrobial activity and potential natural product diversity, which further proved that endophytic actinomycetes
are valuable reservoirs of novel bioactive compounds. 相似文献
10.
A list of the 356 species of Cecidomyiidae (Diptera) recorded from Finland is presented, which comprises 6 Lestremiinae, 156 Micromyinae, 16 Winnertziinae, 69 Porricondylinae, and 109 Cecidomyiinae. The faunistic knowledge of Finnish Winnertziinae, Porricondylinae and Cecidomyiinae is regarded as particularly poor. Based on species numbers known from other countries in Europe, a conservative estimate is 700–800 species of Cecidomyiidae actually occurring in Finland. 相似文献