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1.
S Afele G D Bryant-Greenwood W A Chamley E M Dax 《Journal of reproduction and fertility》1979,56(2):451-457
One sow bled at 30--60-min intervals for 48 h at 5 and 4 days before parturition had mean +/- s.e.m. relaxin levels of 5.0 +/- 0.48 ng/ml and 5.5 +/- 0.44 ng/ml for each 24-h period respectively. This sow and another were bled at frequent intervals during parturition; both showed considerable fluctuations in their relaxin levels but no consistent peaks in relation to each birth. Mean levels during parturition were 10.7 +/- 0.46 ng/ml and 13.4 +/- 0.81 ng/ml respectively, both significantly higher than the levels at 4 and 5 days before birth. Relaxin levels in two lactating sows rose acutely during nursing, showing a 3-fold rise in one animal and an 8-fold rise in the other. Results from a third sow during an extended period of nuzzling and sucking by the piglets showed multiple peaks of relaxin immunoactivity associated with each nuzzling/sucking stimulus. 相似文献
2.
Jurgen Vercauteren Gertjan Beheydt Mattia Prosperi Pieter Libin Stijn Imbrechts Ricardo Camacho Bonaventura Clotet Andrea De Luca Zehava Grossman Rolf Kaiser Anders S?nnerborg Carlo Torti Eric Van Wijngaerden Jean-Claude Schmit Maurizio Zazzi Anna-Maria Geretti Anne-Mieke Vandamme Kristel Van Laethem 《PloS one》2013,8(4)
Introduction
Clinically evaluating genotypic interpretation systems is essential to provide optimal guidance in designing potent individualized HIV-regimens. This study aimed at investigating the ability of the latest Rega algorithm to predict virological response on a short and longer period.Materials & Methods
9231 treatment changes episodes were extracted from an integrated patient database. The virological response after 8, 24 and 48 weeks was dichotomized to success and failure. Success was defined as a viral load below 50 copies/ml or alternatively, a 2 log decrease from the baseline viral load at 8 weeks. The predictive ability of Rega version 8 was analysed in comparison with that of previous evaluated version Rega 5 and two other algorithms (ANRS v2011.05 and Stanford HIVdb v6.0.11). A logistic model based on the genotypic susceptibility score was used to predict virological response, and additionally, confounding factors were added to the model. Performance of the models was compared using the area under the ROC curve (AUC) and a Wilcoxon signed-rank test.Results
Per unit increase of the GSS reported by Rega 8, the odds on having a successful therapy response on week 8 increased significantly by 81% (OR = 1.81, CI = [1.76–1.86]), on week 24 by 73% (OR = 1.73, CI = [1.69–1.78]) and on week 48 by 85% (OR = 1.85, CI = [1.80–1.91]). No significant differences in AUC were found between the performance of Rega 8 and Rega 5, ANRS v2011.05 and Stanford HIVdb v6.0.11, however Rega 8 had the highest sensitivity: 76.9%, 76.5% and 77.2% on 8, 24 and 48 weeks respectively. Inclusion of additional factors increased the performance significantly.Conclusion
Rega 8 is a significant predictor for virological response with a better sensitivity than previously, and with rules for recently approved drugs. Additional variables should be taken into account to ensure an effective regimen. 相似文献3.
4.
Tropical canopy dominance in lowland, well-drained forests by one plant species is a long-standing conundrum in tropical biology. Research now shows that dominance is not the result of one trait or mechanism. We suggest that the striking dominance of Gilbertiodendron dewevrei in the Ituri Forest of northeastern Congo is the result of a number of traits in adult trees that significantly modify the understory environment, making it difficult for other species to regenerate there. Adults cast deep shade that reduces light levels in the understory of the Gilbertiodendron forest to levels significantly lower than in the mixed-species forest. Moreover, the monodominant forest has deep leaf litter that could inhibit the establishment of small-seeded species, and the leaf litter is slow to decompose, potentially causing the low availability of nitrogen. We expect that juveniles of Gilbertiodendron may have an advantage in this environment over other species. In general, it appears that all tropical monodominant species share a similar suite of traits. 相似文献
5.
6.
Cimato AN Piehl LL Facorro GB Torti HB Hager AA 《Free radical biology & medicine》2004,37(12):2042-2051
Liposomes are today useful tools in different fields of science and technology. A lack of stability due to lipid peroxidation is the main problem in the extension of the use of these formulations. Recent investigative works have reported the protective effects of stable nitroxide radicals against oxidative processes in different media and under different stress conditions. Our group has focused its attention on the natural aging of liposomes and the protection provided by the water- and lipid-soluble nitroxide radicals 2,2,6,6-tetramethylpiperdine-1-oxyl (TEMPO) and doxylstearic acids (5-DSA, 12-DSA, and 16-DSA), respectively. Unilamellar liposomes were incubated under air atmosphere at 37°C, both in the absence and in the presence of these radicals. Conjugated dienes, lipid hydroperoxides, TBARS, membrane fluidity, and nitroxide ESR signal intensity were followed as a function of time. Our results demonstrated that doxylstearic acids were more efficient than TEMPO in retarding lipid peroxidation at all the concentrations tested. The inhibition percentages, depending on the total nitroxide concentration, were not proportional to the lipid–water partition coefficient. Furthermore, time-course ESR signals showed a slower decrease for doxylstearic acids than for TEMPO. No significant differences were found among 5-DSA, 12-DSA, and 16-DSA. We concluded that the nitroxide radical efficiency as antioxidant directly depends on both nitroxide concentration and lipophilicity. 相似文献
7.
Jablonowski JA Chai W Li X Rudolph DA Murray WV Youngman MA Dax SL Nepomuceno D Bonaventure P Lovenberg TW Carruthers NI 《Bioorganic & medicinal chemistry letters》2004,14(5):1239-1242
Through SAR studies of a piperidinylindoline cinnamide HTS lead, the first potent, non-peptide, low molecular weight selective Neuropeptide Y Y2 (NPY Y2) antagonists have been synthesized. The SAR studies around the piperidinyl, the indolinyl, and the cinnamyl moieties are discussed. 相似文献
8.
Planalp RP Przyborowska AM Park G Ye N Lu FH Rogers RD Broker GA Torti SV Brechbiel MW 《Biochemical Society transactions》2002,30(4):758-762
To achieve cellular iron deprivation by chelation, it is important to develop chelators with selective metal-binding properties. Selectivity for iron has long been the province of certain oxygen-donor chelators such as desferrioxamine, which target Fe(III) and exploit the strength of a relatively ionic Fe(III)-O interaction. We have been studying novel chelators that possess mechanisms to selectively chelate +2 biometals, particularly tachpyr [N,N',N"-tris(2-pyridylmethyl)-1,3,5-cis,cis-triaminocyclohexane] and derivatives from N,N',N"-trialkylation and pyridine ring alkylation. Metal-exchange and metal-binding competition reactions have been conducted at pH 7.4, 37 degrees C and time periods until no further change was observed (generally 24-48 h). Under anaerobic conditions, tachpyr is strongly selective for iron, binding 95+/-5% Fe(II) versus 5+/-5% Zn(II) in the forms [Fe(tachpyr)](2+) and [Zn(tachpyr)](2+) respectively. Under aerobic conditions, tachpyr complexes Fe(II) more effectively than Fe(III), forming iminopyridyl complexes [Fe(tachpyr-ox-n)](2+) (n=2, 4) by O(2)-induced and iron-mediated oxidative dehydrogenation. Complexes [Fe(tachpyr-ox-n)](2+) are also strongly bound forms of iron that are unaffected by an excess of Zn(II) (75 mol zinc:1 mol iron complex). The preference of tachpyr for iron over zinc under aerobic conditions appears to be hindered by oxidation of Fe(II) to Fe(III), such that the proportions bound are 44+/-10% Fe(II) versus 56+/-10% Zn(II), in the respective forms [Fe(tachpyr-ox-n)](2+) and [Zn(tachpyr)](2+). However, upon addition of the reducing agent Na(2)S(2)O(4) that converts Fe(III) to Fe(II), the binding proportions shift to 76+/-10% Fe(II) versus 24+/-10% Zn(II), demonstrating a clear preference of tachpyr for Fe(II) over Zn(II). Iron(II) is in the low-spin state in [Fe(tachpyr)](2+) and [Fe(tachpyr-ox-n)](2+) (n=2, 4), which is a likely cause of the observed selectivity. N-methylation of tachpyr [giving (N-methyl)(3)tachpyr] results in the loss of selectivity for Fe(II), which is attributed to the steric effect of the methyl groups and a resulting high-spin state of Fe(II) in [Fe(N-methyl)(3)tachpyr)](2+). The relationship of chelator selectivity to cytotoxicity in the tach family will be discussed. 相似文献
9.
Nucleotide variation,haplotype structure,and association with end-stage renal disease of the human interleukin-1 gene cluster 总被引:3,自引:0,他引:3
Bensen JT Langefeld CD Hawkins GA Green LE Mychaleckyj JC Brewer CS Kiger DS Binford SM Colicigno CJ Allred DC Freedman BI Bowden DW 《Genomics》2003,82(2):194-217
A dense gene-based SNP map was constructed across a 360-kb region containing the interleukin-1 gene cluster (IL1A, IL1B, and IL1RN), focusing on IL1RN. In total, 95 polymorphisms were confirmed or identified primarily by direct sequencing. Polymorphisms were precisely mapped to completed BAC and genomic sequences spanning this region. The polymorphisms were typed in 443 case-control subjects from Caucasian and African American groups. Consecutive pair-wise marker linkage disequilibrium was not strictly correlated with distance and ranged from D'=0.0079 to 1.000 and D'=0.0521 to 1.0000 in Caucasians and African Americans, respectively. Single markers and haplotypes in IL1 cluster genes were evaluated for association with end-stage renal disease (ESRD). Eleven SNPs show some evidence of association with ESRD, with the strongest associations in two IL1A variants, one SNP, rs1516792-3, in intron 5 (p=0.0015) and a 4-bp insertion/deletion within the 3'UTR, rs16347-2 (p=0.0024), among African Americans with non-T2DM-associated ESRD. 相似文献
10.
Gruber HJ Hahn CD Kada G Riener CK Harms GS Ahrer W Dax TG Knaus HG 《Bioconjugate chemistry》2000,11(5):696-704
This study provides a critical examination of protein labeling with Cy3, Cy5, and other Cy dyes. Two alternate situations were tested. (i) Antibodies were covalently labeled with Cy dye succinimidyl ester at various fluorophore/protein ratios and the fluorescence of the labeled antibodies was compared to that of free Cy dye. (ii) Fluorescent biotin derivatives were synthesized by derivatizing ethylenediamine with one biotin and one Cy3 (or Cy5) residue. The fluorescence properties of these biotin-Cy dye conjugates were examined at all ligand/(strept)avidin ratios (0 = n = 4). The results showed an astounding discrepancy between Cy3 and Cy5: Cy3-labeled antibodies fluoresced very well, even at high Cy3/protein ratios, and the same applied to (strept)avidin with up to four bound biotin-Cy3 conjugates. In contrast, antibodies with six covalently bound Cy5 labels (obtained with the recommended procedure) were almost nonfluorescent, only at 2-3 Cy5 labels/IgG some moderate fluorescence was obtained. By analogy, the biotin-Cy3 conjugate fluoresced intensely, even at high ligand/avidin ratio, in contrast to the weakly fluorescing biotin-Cy5 conjugate. Three mechanisms are responsible for the discrepancy between Cy3 and Cy5. (i) Attachment of Cy3 to a protein's surface causes an anomalous enhancement in fluorescence (by 2-3-fold) while no enhancement occurs with Cy5. (ii) Mutual quenching of IgG-bound Cy dyes by resonance energy transfer is much more pronounced for Cy5 labels than for Cy3. (iii) In IgG with six bound Cy5 labels, about one-third of the labels adopt a nonfluorescent state which is characterized by a large UV-vis absorption maximum at 600 nm instead of at 650 nm. Cy3.5 was found to mimick the properties of Cy3, while Cy7, and to some extent also Cy5.5, were similar to Cy5. In conclusion the Cy dye series is divided into two groups: Antibodies with multiple Cy3 or Cy3.5 labels yield bright fluorescence while extensive quenching occurs in antibodies labeled with Cy5 and Cy7. 相似文献