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171.
A mammary gland EST showing linkage disequilibrium to a milk production QTL on bovine Chromosome 14 总被引:10,自引:0,他引:10
Christian Looft Norbert Reinsch Christina Karall-Albrecht Sven Paul Maren Brink Hauke Thomsen Gudrun Brockmann Christa Kühn Manfred Schwerin Ernst Kalm 《Mammalian genome》2001,12(8):646-650
As part of a genome scan, ESTs derived from mammary gland tissue of a lactating cow were used as candidate genes for quantitative
trait loci (QTL), affecting milk production traits. Resource families were genotyped with 247 microsatellite markers and 4
polymorphic ESTs. It was shown by linkage analysis that one of these ESTs, KIEL_E8, mapped to the centromeric region of bovine
Chromosome (Chr) 14. Regression analysis revealed the presence of a QTL, with significant effect on milk production, in this
chromosome region, and analysis of variance showed no significant interaction of marker genotype and family. The estimated
significant differences between homozygous marker genotypes were 140 kg milk, −5.02 kg fat yield, and 2.58 kg protein yield
for the first 100 days of lactation. Thus, there was strong evidence for a complete or nearly complete linkage disequilibrium
between KIEL_E8 and the QTL. To identify the biological function of KIEL_E8, we extended the sequence for 869 bp by 5′-RACE.
A 560-bp fragment of this shows a 90.9% similarity to a gene encoding a cysteine- and histidine-rich cytoplasmic protein in
mouse. Although such a protein may have a regulatory function for lactation and a linkage disequilibrium between the EST marker
and the QTL has been observed, it remains to be elucidated whether they are identical or not. Nevertheless, KIEL_E8 will be
an efficient marker to perform marker-assisted selection in the Holstein-Friesian population.
Received 20 October 2000 / Accepted: 11 April 2001 相似文献
172.
Christa Kirberger 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1953,35(3):153-158
Zusammenfassung Bei einer raschen Temperatursteigerung wird die Leistungsfähigkeit des Blutes hinsichtlich der Sauerstoffaufladung durch eine Rechtsverschiebung der Dissotiationskurve herabgesetzt. Rana esculenta besitzt 2 Regulationen, um diesen Effekt zum Teil zu kompensieren. Überführt man kalt-angepaßte Tiere in mittlere Temperaturen und beläßt sie in diesen, so steigert sich durch einen langsam einsetzenden Anpassungsvorgang der Hämoglobingehalt des Blutes. Nach Umsetzen der Frösche in noch höhere Temperaturen wird durch einen weiteren Regulationsvorgang die Sauerstoffaffinität, d. h. der Sauerstoffgehalt, bezogen auf gleiche Hämoglobinmengen, gesteigert, wodurch die Rechtsverschiebung der Dissoziationskurve teilweise wieder rückgängig gemacht wird. Beide Regulationen sind reversibel.Dissertation bei der Philosophischen Fakultät der Universität Kiel, Teil II (Anregung und Anleitung: Prof. Dr. H. Precht). Die photometrischen Messungen wurden mit einem Pulfrich-Photometer ausgeführt, welches die Deutsche Forschungsgemeinschaft Herrn Prof. Precht zur Verfügung stellte. 相似文献
173.
Summary The frequency of sister chromatid exchanges (SCEs) in the centromere of chromosomes involved in a whole-arm translocation t(1;19) was evaluated in altogether 911 metaphases of translocation carriers (n=5) and of normal controls (n=6). Comparison of the two groups reveals no significant differences in the SCE rate (x
2=3.06, n
f
=1). The question as to whether the possible increase of the SCE rate at the translocation point could be detected by light microscopy is discussed. Parameters included in the discussion are the ratio of the SCE frequency at the translocation point to the SCE frequency at any of the possible breakage points in the centromeric region and the number of possible breakage points in the centromeric region. 相似文献
174.
175.
Multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) are highly influenced by changes in the microbiota and of microbiota-derived metabolites, including short chain fatty acids, bile acids, and tryptophan derivatives. This review will discuss the effects of microbiota-derived metabolites on neuroinflammation driven by central nervous system-resident cells and peripheral immune cells, and their influence on outcomes of EAE and MS. 相似文献
176.
Jens Baumert Christin Heidemann Rebecca Paprott Yong Du Christa Scheidt-Nave 《BMC endocrine disorders》2018,18(1):95
Background
Random glucose is widely measured in epidemiological studies and in the clinical setting when standardized fasting protocols and oral glucose tolerance testing or HbA1c measuring are not feasible. The relationship between random glucose and all-cause mortality has hardly been studied so far and was examined in the present study.Methods
We ascertained mortality status among 5955 persons aged 18–79?years and free of known diabetes when participating in the German National Health Interview and Examination Survey 1998 (mean observation time 11.7?years, 458 deaths). Cox regression was applied to analyze the association of random serum glucose with all-cause mortality taken potential confounders into account. Relative mortality risks were estimated as hazard ratios (HRs) with 95% confidence intervals (CIs) modeling random glucose as categorical or continuous variable.Results
Compared to random glucose levels of 4.3 -?<?5.3?mmol/L, HRs (95% CIs) were 1.94 (0.85–4.45) for levels <?4.3?mmol/L and 1.16 (0.89–1.50), 1.20 (0.91–1.58), 1.42 (0.88–2.29), 2.02 (1.26–3.25) and 4.71 (2.20–10.10) for levels 5.3 -?<?5.8, 5.8 -?<?6.8, 6.8 -?<?7.8, 7.8 -?<?11.1 and?≥?11.1?mmol/L, adjusted for age, sex, lifestyle, anthropometry and chronic diseases. An additional adjustment for fasting time or HbA1c yielded similar estimates. Modeling continuous random glucose by restricted cubic spline functions revealed comparable findings.Conclusions
In the present epidemiological study drawn from the general population, random glucose showed a significant association with all-cause mortality, independent of main potential confounders. Thus, random glucose measures are highly relevant to health risk assessment among people without known diabetes when fasting glucose or HbA1c are difficult to obtain.177.
Targeted On‐line SPE‐LC‐MS/MS Assay for the Quantitation of 12 Apolipoproteins from Human Blood
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Julia Dittrich Melanie Adam Hilke Maas Max Hecht Madlen Reinicke L. Renee Ruhaak Christa Cobbaert Christoph Engel Kerstin Wirkner Markus Löffler Joachim Thiery Uta Ceglarek 《Proteomics》2018,18(3-4)
Laborious sample pretreatment of biological samples represents the most limiting factor for the translation of targeted proteomics assays from research to clinical routine. An optimized method for the simultaneous quantitation of 12 major apolipoproteins (apos) combining on‐line SPE and fast LC‐MS/MS analysis in 6.5 min total run time was developed, reducing the manual sample pretreatment time of 3 μL serum or plasma by 60%. Within‐run and between‐day imprecisions below 10 and 15% (n = 10) and high recovery rates (94–131%) were obtained applying the high‐throughput setup. High‐quality porcine trypsin was used, which outperformed cost‐effective bovine trypsin regarding digestion efficiency. Comparisons with immunoassays and another LC‐MS/MS assay demonstrated good correlation (Pearson's R: 0.81–0.98). Further, requirements on sample quality concerning sampling, processing, and long‐term storage up to 1 year were investigated revealing significant influences of the applied sampling material and coagulant on quantitation results. Apo profiles of 1339 subjects of the LIFE‐Adult‐Study were associated with lifestyle and physiological parameters as well as establish parameters of lipid metabolism (e.g., triglycerides, cholesterol). Besides gender effects, most significant impact was seen regarding lipid‐lowering medication. In conclusion, this novel highly standardized, high‐throughput targeted proteomics assay utilizes a fast, simultaneous analysis of 12 apos from least sample amounts. 相似文献
178.
The removal of Ca2+ from the medium by intact vacuoles and microsomes of Chenopodium album was investigated by measuring INDO-1 fluorescence emission at 400 and 480 nm and the response of Ca2+ -selective mini-electrodes. The removal of Ca2+ depended on the presence of MgATP, displaying an apparent K
mATP of about 50 μM, a K
mCa of 400–500 nM, and a nucleotide specificity (%) of ATP (100) > CTP (49) > GTP (28) > UTP (20) > ADP = AMP (0). In the presence
of saturating MgATP, the vacuoles reduced the [Ca2+] of the medium below 30 nM. Part of the Ca2+ removed from the medium was released again after adding micromolar concentrations of inositol-1,4,5-trisphosphate. This release
of Ca2+ was inhibited by heparin. Since digitonin caused the release of the entire amount of Ca2+ removed from the medium in the presence of MgATP, we argue that the Ca2+ is not bound to membranes or sequestered otherwise, but is transported into the vacuoles (or vesicles) and remains freely
mobile there. In accordance with the current literature, we conclude that the plant vacuole is an important store for mobile
Ca2+ to be released for purposes of signal transduction. Since changes in the trans-tonoplast ΔpH and inhibition of the H+-translocating pumps had no significant influence on the ATP-dependent removal of Ca2+ from the cytoplasmic side, we argue that in C. album ATP-driven Ca2+ transport is the predominant form of Ca2+ translocation into the vacuole.
Received: 11 July 1996 / Accepted: 18 October 1996 相似文献
179.
Ferdinand Bohlmann Christa Zdero Jasmin Jakupovic Laxmi N. Misra Shanta Banerjee Pahup Singh Robindra N. Baruah Mohamed A. Metwally Guillermo Schmeda-Hirschmann Leszek P.D. Vincent Robert M. King Harold Robinson 《Phytochemistry》1985,24(6):1249-1261
The investigation and reinvestigation respectively of 23 Senecio species afforded 11 further cacalol derivatives, a furoeremophilone, 17 eremophilanes, 4 bisabolene derivatives, a shikimic acid derivative, a bis-prenylated p-hydroxybenzaldehyde, menth-2-en- 1,7-diol and a cumol derivative. The configuration of some eremophilanes have been revised. Structures were elucidated by spectroscopic methods. The results are summarized in a table. The chemotaxonomic aspects agree with those of previous investigations. 相似文献
180.
Ferdinand Bohlmann Lievy Hartono Christa Zdero Jasmin Jakupovic 《Phytochemistry》1985,24(5):1111-1112
The aerial parts of Oxylobus arbutifolius and O. adscendens gave eudesmanolides and labdane derivatives as well as two new euparin derivatives. 相似文献