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31.
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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Brendan J. Humphries Peter J. Abernethy Kirsten D. Blake Robert U. Newton 《European journal of applied physiology and occupational physiology》1997,75(6):532-536
The relative content of myosin heavy chain (MHC) isoforms IIb, IIa and I in human skeletal muscle taken from the m. vastus
lateralis of 30 healthy male subjects was analysed using mini-gel electrophoresis. Repeated electrophoretic gels utilizing
the same methods were produced for all subjects and the determination of MHC protein bands was performed using a digital scanner
and National Institutes of Health (NIH) Image software and laser densitometry. A comparison between the NIH Image processing
technique and laser densitometry revealed differences of 6.47%, 6.35% and 6.84% between these measurement techniques for MHC-IIb,
-IIa and -I isoforms, respectively. The percentage technical error of measurement (TEM%) between electrophoretic gels was
shown to be 19.1%, 17.8% and 14.2%, with regard to percentage of occurrence of MHC-IIb, -IIa and -I isoforms respectively.
The variation in electrophoretic gel analyses was shown to be 5.7%, 7.3% and 5.5%, with regard to the percentage of MHC-IIb,
-IIa and -I isoforms respectively. Intra-class correlations comparing NIH Image and laser densitometry produced r values in the range 0.38–0.63. Comparisons between and within gel analyses produced r values in the range 0.59–0.94 and 0.93–0.98, respectively. Analyses of variance revealed no significant differences (P < 0.05) between analysis techniques, between␣gels or within gels for the measurement of MHC-IIb, -IIa and -I isoforms. The inter-gel
error between fibre subgroups was moderate for the two type-II MHC populations and less for type-I MHC; the intra-individual
error in the measuring technique used for classifying the MHC-IIb, -IIa and -I protein bands was small. The results obtained
in this investigation showed consistent trends which may reflect a false classification of the type-II MHC populations for
the inter-gel and intra-individual analyses. The NIH Image software and digitizing process was shown to be a valid and reliable
method for distinguishing between MHC protein bands of human skeletal tissue as separated by mini-gel electrophoretic techniques.
Accepted: 6 January 1997 相似文献
35.
Goring DR Banks P Fallis L Baszczynski CL Beversdorf WD Rothstein SJ 《The Plant journal : for cell and molecular biology》1992,2(6):999-1003
We have previously described a developmentally regulated mRNA in maize that accumulates in mature embryos and is involved in a variety of stress responses in the plant. The sequence of the encoded 16 kDa protein (MA16) predicts that it is an RNA-binding protein, since it possesses a ribonucleoprotein consensus sequence-type RNA-binding domain (CS-RBD). To assess the predicted RNA binding property of the protein and as a starting point to characterize its function we have used ribohomopolymer-binding assays. Here we show that the MA16-encoded protein binds preferentially to uridine- and guanosine-rich RNAs. In light of these results a likely role for this protein in RNA metabolism during late embryogenesis and in the stress response is discussed. 相似文献
36.
Single‐nucleotide polymorphism discovery and panel characterization in the African forest elephant 下载免费PDF全文
Stéphanie Bourgeois Helen Senn Jenny Kaden John B. Taggart Rob Ogden Kathryn J. Jeffery Nils Bunnefeld Katharine Abernethy Ross McEwing 《Ecology and evolution》2018,8(4):2207-2217
The continuing decline in forest elephant (Loxodonta cyclotis) numbers due to poaching and habitat reduction is driving the search for new tools to inform management and conservation. For dense rainforest species, basic ecological data on populations and threats can be challenging and expensive to collect, impeding conservation action in the field. As such, genetic monitoring is being increasingly implemented to complement or replace more burdensome field techniques. Single‐nucleotide polymorphisms (SNPs) are particularly cost‐effective and informative markers that can be used for a range of practical applications, including population census, assessment of human impact on social and genetic structure, and investigation of the illegal wildlife trade. SNP resources for elephants are scarce, but next‐generation sequencing provides the opportunity for rapid, inexpensive generation of SNP markers in nonmodel species. Here, we sourced forest elephant DNA from 23 samples collected from 10 locations within Gabon, Central Africa, and applied double‐digest restriction‐site‐associated DNA (ddRAD) sequencing to discover 31,851 tags containing SNPs that were reduced to a set of 1,365 high‐quality candidate SNP markers. A subset of 115 candidate SNPs was then selected for assay design and validation using 56 additional samples. Genotyping resulted in a high conversion rate (93%) and a low per allele error rate (0.07%). This study provides the first panel of 107 validated SNP markers for forest elephants. This resource presents great potential for new genetic tools to produce reliable data and underpin a step‐change in conservation policies for this elusive species. 相似文献
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During the initial 9 to 12 hours of imbibition, the imbibing wheat (Triticum aestivum L.) seed was found to exhibit substantial tolerance to high temperature relative to later times of imbibition. Tolerance was assessed by seed viability and seedling growth. This initial high temperature tolerance gradually declines with increasing time of seed imbibition. A range of 2 hour heat pretreatments (38-42°C) prior to imposition of a 2 hour heat shock (51-53°C) during this same 9 to 12 hour interval was unable to increase survival or seedling growth over that of seed that did not receive a pretreatment. However, after 9 to 12 hours of imbibition the pretreatment provided both increased survival and increased seedling growth, measured 120 hours later, i.e., classical thermotolerance could be acquired. This response is called a `thermotolerance transition.' Isolated embryos responded in a similar manner using a 2,3,5-triphenyltetrazolium chloride assay for viability determination following heat treatments. The high temperature tolerance during early imbibition indicates that the thermotolerance transition involves the loss of an existing thermotolerance coincident with acquiring the ability to become thermotolerant following heat pretreatment. Despite the inability to acquire thermotolerance, heat shock protein synthesis was induced by heat shock immediately upon imbibition of wheat seed or isolated embryos. Developmentally regulated heat shock proteins of 58 to 60, 46, 40, and 14 kilodaltons were detected at 1.5 hours of imbibition following heat shock, but were absent or greatly reduced by 12 hours. Constitutive synthesis of 70 and 90 kilodalton hsp groups appeared to be greater at 1.5 hours of imbibition than at 12 hours of imbibition. 相似文献
39.
Bovine erythrocyte superoxide dismutase. Complete amino acid sequence 总被引:15,自引:0,他引:15
H M Steinman V R Naik J L Abernethy R L Hill 《The Journal of biological chemistry》1974,249(22):7326-7338
40.
J Abernethy 《Journal of theoretical biology》1973,39(3):589-600
A change in the electrolyte concentration in a multicomponent system will in general change the activity of non-electrolyte species, a particular example being the salting-out of dissolved gases (although for some solutes a salting-in effect occurs). It follows that countercurrent multiplication of sodium ions in the renal medulla will inevitably be associated with change in activity of non-electrolytes since this process is characterized by two orthogonal [Na +] gradients in the multiplier loop, the one longitudinal, the other transverse. Using a single loop model we show that the two [Na+] gradients act independently to produce opposing effects on activity so that given, say, a salting-out effect, the longitudinal gradient effects an increase in activity and the transverse a decrease, both being dependent on the magnitude of the interaction. In the latter case, since attenuation results from direct involvement of the solute in the countercurrent multiplication process, the diffusion coefficient of necessity also has a positive influence. In the non-steady state we show that a measure of the time taken to reach equilibrium varies with the square of the transit time of tubular fluid. This means that there are likely to be transient activity differences between the two countercurrent systems, active and passive, in the medulla. Urine appears to be in equilibrium with the inner medulla and so will reflect these activity changes in the steady and non-steady state. This analysis is consistent with previous experimental findings on urinary inert gases. These results could suggest an indirect method of monitoring countercurrent multiplication of sodium. There are also implications for clinical studies since it is often assumed that urine reflects blood concentrations of biologically inert solutes. 相似文献