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31.
Cryptosporidium parvum contains a unique fusion protein pyruvate:NADP+ oxidoreductase (CpPNO) that is composed of two distinct, conserved domains, an N-terminal pyruvate:ferredoxin oxidoreductase (PFO) and a C-terminal cytochrome P450 reductase (CPR). Unlike a similar fusion protein that localizes to the mitochondrion of the photosynthetic protist Euglena gracilis, CpPNO lacks an N-terminal mitochondrial targeting sequence. Using two distinct polyclonal antibodies raised against CpPFO and one polyclonal antibody against CpCPR, Western blot analysis has shown that sporozoites of C. parvum express the entire CpPNO fusion protein. Furthermore, confocal immunofluorescence and transmission electron microscopy confirm that CpPNO is localized within the cytosol rather than the relict mitochondrion of C. parvum. The distribution of this protein is not, however, strictly confined to the cytosol. CpPNO also appears to localize posteriorly within the crystalloid body. 相似文献
32.
In this paper Freud's work on animism and magic is elaborated. Those two subjects are presented mainly in his work "Totem and Taboo" (1913). The true motives, which lead primitive man to practice magic are, according to Freud, human whishes and his immense belief in their power. Importance attached to wishes and to the will has been extended from them to all those psychical acts, which are subjected to will. A general overvaluation has thus come about of all mental processes. Things become less important than ideas of things. Relations, which hold between the ideas of things, are equally hold between the things. The principle of governing magic or the technique of animistic way of thinking is one of the 'omnipotence of thoughts'. The overvaluation of psychic acts could be brought into relation with narcissism and megalomania, a belief in the thaumaturgic force of words and a technique for dealing with the external world--'magic'--which appears to be a logical application of these grandiose premises. Recent psychoanalytic authors dealing with the problem of magic emphasize that magic survived culturally to the present days and even in adults who are otherwise intellectually and scientifically 'modern'. Their explanations for that derive from Ferenczi's and especially Róheim's work that pointed out that magic facilitates adaptive and realistically effective endeavors. Balter pointed out that magic employs ego functioning, and conversely ego functioning includes magic. 相似文献
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34.
Transport of radioactive iodide 131I? in a black clay loam soil under spring barley in an early ontogenesis phase was monitored during controlled field irrigation experiment. It was found that iodide bound in the soil matrix could be mobilized by the surface leaching enhanced by mechanical impact of water drops and transported below the root zone of crops via soil cracks. The iodide transport through structured soil profile was simulated by the one-dimensional dual-continuum model, which assumes the existence of two inter-connected flow domains: the soil matrix domain and the preferential flow domain. The model predicted relatively deep percolation of iodide within a short time, in a good agreement with the observed vertical iodide distribution in soil. The dual-continuum approach proved to be an adequate tool for evaluation of field irrigation experiments conducted in structured soils. 相似文献
35.
36.
Mario Šlaus Mario Novak Vlasta Vyroubal Željka Bedić 《American journal of physical anthropology》2010,141(3):358-372
Excavation of the historic period cemetery in ?epin, Croatia revealed the presence of a large number of perimortem injuries distributed among males, females, and subadults. Archaeological and historical data suggest these individuals were victims of a raid carried out by Turkish akinji light cavalry in 1441. Comparisons with the frequencies of perimortem trauma in 12 other, temporally congruent skeletal series from the Balkans (n = 2,123 skeletons) support this assumption. The role of the akinji in the Ottoman army was twofold: to supply war captives, and to terrorize and disperse local populations before the advance of regular troops. This article tests the hypothesis that the purpose of the 1441 raid was the latter. To accomplish this, perimortem trauma in the series were analyzed by sex, age, location, and depth of the injury. A total of 82 perimortem injuries were recorded in 12 males, 7 females, and 3 subadults. The demographic profile of the victims suggests that young adults were specifically targeted in the attack. Significant sex differences are noted in the number, distribution, and pattern of perimortem trauma. Females exhibit significantly more perimortem injuries per individual, and per bone affected, than males. The morphology and pattern of perimortem trauma in females is suggestive of gratuitous violence. Cumulatively, analysis of the osteological data suggest that the objective of the 1441 akinji raid was to spread terror and panic in the ?epin area, either as revenge for recent military setbacks, or as part of a long‐term strategy intended to depopulate the area around Osijek. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
37.
Ian Oswald S. A. Lewis D. L. F. Dunleavy Vlasta Brezinova Marion Briggs 《BMJ (Clinical research ed.)》1971,3(5766):70-73
Measures of subjective feeling used by five patients indicated that depression of mood occurred about four days after fenfluramine withdrawal. An experiment in which another 11 patients took fenfluramine 80 mg for 28 days confirmed the depression, maximal on the fourth withdrawal day. It also indicated that in the first week of administration there was some mood elevation, but with feelings of impaired ability to concentrate. The drug reduced appetite and weight. A comparison is drawn with imipramine, which was found to induce initial and withdrawal changes of subjective experience (of dreaming) in six volunteers. It is suggested that certain mood-influencing drugs may not be drugs of abuse because of some unpleasant initial effects, though they can be drugs of dependence. 相似文献
38.
Summary One of the factors giving rise to soil sickness in apple orchards is the rhizosphere microflora. The composition of the microbial
coenosis in the rhizosphere changes with increasing age of the apple trees. An increase in the counts of micromycetes and
actinomycetes and a decrease in bacterial counts was found in agreement with the decreasing pH of the rhizosphere soil. The
presence of fluorescent pseudomonads in the rhizosphere of old apple trees was rare, but the planting of apple seedling into
sick soil induced their proliferation. The relative proportion of individual genera of micromycetes changed according to the
tree age; fungi of the genus Mucor were more often found in the rhizosphere of younger trees than in that of older ones while
fungi of the genus Penicillium had an opposite trend. Biological tests showed that Penicillium fungi form the majority of
the phytotoxic microflora. The amount of phytotoxic micromycetes was higher in ‘sick’ soil as compared with control soil in
which apple trees had not been grown for at least 15 years. Higher numbers of phytotoxic micromycetes were isolated also from
the rhizosphere of apple seedlings grown in ‘sick’ soil as compared with those growing in control soil. An increase in the
amount of phytotoxic micromycetes in apple tree rhizosphere could be induced by mere addition of 5% (w/w) ‘sick’ soil to the
soil in which apple trees were grown for the first time. By adding sterilized ‘sick’ soil, the amount of phytotoxic micromycetes
in the apple seedling rhizosphere was not affected. Increased numbers of phytotoxic micromycetes affected negatively the growth
of apple trees and the morphology of apple tree roots. This demonstrated the possibility of transfer of a factor participating
in the etiology of soil sickness in apple orchards. 相似文献
39.
Fatty acid transport in Saccharomyces cerevisiae. Directed mutagenesis of FAT1 distinguishes the biochemical activities associated with Fat1p 总被引:1,自引:0,他引:1
The fatty acid transport protein Fat1p functions as a component of the long-chain fatty acid transport apparatus in the yeast Saccharomyces cerevisiae. Fat1p has significant homologies to the mammalian fatty acid transport proteins (FATP) and the very long-chain acyl-CoA synthetases (VLACS). In order to further understand the functional roles intrinsic to Fat1p (fatty acid transport and VLACS activities), a series of 16 alleles carrying site-directed mutations within FAT1 were constructed and analyzed. Sites chosen for the construction of amino acid substitutions were based on conservation between Fat1p and the mammalian FATP orthologues and included the ATP/AMP and FATP/VLACS signature motifs. Centromeric and 2 mu plasmids encoding mutant forms of Fat1p were transformed into a yeast strain containing a deletion in FAT1 (fat1Delta). For selected subsets of FAT1 mutant alleles, we observed differences between the wild type and mutants in 1) growth rates when fatty acid synthase was inhibited with 45 microm cerulenin in the presence of 100 microm oleate (C(18:1)), 2) levels of fatty acid import monitored using the accumulation of the fluorescent fatty acid 4,4-difluoro-5-methyl-4-bora-3a,4a-diaza-S-indacene-3-dodecanoic acid and [(3)H]oleate, 3) levels of lignoceryl (C(24:0)) CoA synthetase activities, and 4) fatty acid profiles monitored using gas chromatography/mass spectrometry. In most cases, there was a correlation between growth on fatty acid/cerulenin plates, the levels of fatty acid accumulation, very long-chain fatty acyl-CoA synthetase activities, and the fatty acid profiles in the different FAT1 mutants. For several notable exceptions, the fatty acid transport and very long-chain fatty acyl-CoA synthetase activities were distinguishable. The characterization of these novel mutants provides a platform to more completely understand the role of Fat1p in the linkage between fatty acid import and activation to CoA thioesters. 相似文献
40.
Racek J Trefil L Rajdl D Mudrová V Hunter D Senft V 《Biological trace element research》2006,109(3):215-230
The aim of this study was to determine the effect of chromium (Cr)-enriched yeast on blood glucose and insulin variables,
blood lipids, and blood markers of oxidative stress in persons with type 2 diabetes mellitus (median duration: 3.0 yr). Thirty-six
subjects (9 men, 27 women; mean age: 61.3 yr; mean body mass index: 34.33 kg/m2) were supplemented with 400 μg Cr/d as Cr-enriched yeast (n=19) or placebo (n=17) for 12 wk in a randomized, double-blind study. The most interesting results were obtained by comparison of the change
in the placebo group to the change in the Cr group. The Cr group showed a significantly greater increase in serum Cr compared
to the placebo group (p<0.05). Supplementation with Cr-enriched yeast was associated with a significant decrease in fasting serum glucose compared
to placebo (p<0.01). Blood markers of oxidative stress glutathione peroxidase activity and levels of reduced glutathione were essentially
unchanged in the Cr group after 12 wk, but decreased significantly in the placebo group (p<0.05, p<0.01, respectively), Serum HbA1c and glycated protein (fructosamine) were essentially unchanged in the Cr group, whereas HbA1c tended to increase in the placebo group (from 6.94% to 7.11%). Fasting serum insulin decreased in both groups, with a greater
tendency in the Cr group (−16.5% vs −9.5%). These data suggest that supplementation of well-controlled type 2 diabetics with
Cr-enriched yeast is safe and can result in improvements in blood glucose variables and oxidative stress. 相似文献