全文获取类型
收费全文 | 111篇 |
免费 | 3篇 |
出版年
2023年 | 1篇 |
2021年 | 2篇 |
2018年 | 1篇 |
2017年 | 4篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 6篇 |
2011年 | 2篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 6篇 |
2007年 | 2篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 5篇 |
1999年 | 6篇 |
1998年 | 3篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1976年 | 1篇 |
1974年 | 3篇 |
1972年 | 2篇 |
排序方式: 共有114条查询结果,搜索用时 15 毫秒
21.
22.
T. B. Vree A. J. Lagerwerf C. P. Bleeker P. M. R. M. de Grood 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1999,721(2):71
Propofol (P) is metabolized in humans by oxidation to 1,4-di-isopropylquinol (Q). P and Q are in turn conjugated with glucuronic acid to the respective glucuronides, propofol glucuronide (Pgluc), quinol-1-glucuronide (Q1G) and quinol-4-glucuronide (Q4G). Propofol and quinol with their glucuronide conjugates can be measured directly by gradient high-performance liquid chromatographic analysis without enzymic hydrolysis. The glucuronide conjugates were isolated by preparative HPLC from human urine samples. The glucuronides of P and Q were present in plasma and urine, P and Q were present in plasma, but not in urine. Quinol in plasma was present in the oxidised form, the quinone. Calibration curves of the respective glucuronides were constructed by enzymic deconjugation of isolated samples containing different concentrations of the glucuronides. The limit of quantitation of P and quinone in plasma are respectively 0.119 and 0.138 μg/ml. The limit of quantitation of the glucuronides in plasma are respectively: Pgluc 0.370 μg/ml, Q1G 1.02 μg/ml and Q4G 0.278 μg/ml. The corresponding values in urine are: Pgluc 0.264 μg/ml, Q1G 0.731 μg/ml and Q4G 0.199 μg/ml. A pharmacokinetic profile of P with its metabolites is shown, and some preliminary pharmacokinetic parameters of P and Q glucuronides are given. 相似文献
23.
24.
Anne S Rasmussen Henrik Lauridsen Christoffer Laustsen Bjarke G Jensen Steen F Pedersen Lars Uhrenholt Lene WT Boel Niels Uldbjerg Tobias Wang Michael Pedersen 《BMC physiology》2010,10(1):3
Background
In biomedical sciences, ex vivo angiography is a practical mean to elucidate vascular structures three-dimensionally with simultaneous estimation of intravascular volume. The objectives of this study were to develop a magnetic resonance (MR) method for ex vivo angiography and to compare the findings with computed tomography (CT). To demonstrate the usefulness of this method, examples are provided from four different tissues and species: the human placenta, a rice field eel, a porcine heart and a turtle. 相似文献25.
26.
Paralogous origin of the red- and green-sensitive visual pigment genes in vertebrates 总被引:1,自引:0,他引:1
The nucleotide sequence of the red-sensitive visual pigment gene, R007Af,
in the fish Astyanax fasciatus, from the initiation codon to the stop codon
of this gene, including introns, is 1,592 bp, making it the shortest visual
pigment gene known in vertebrates. Analysis of this and other homologous
sequence data suggests that vertebrates initially had two duplicate genes
and that each ancestor of Astyanax, human, and chicken independently
duplicated the gene in the process of developing their red-green color
vision. Furthermore, many extant red-green colorblind organisms may be
explained simply by the failure of achieving very specific nucleotide
substitutions at the three codon positions 180, 277, and 285, rather than
by the lack of duplicate loci.
相似文献
27.
Unusual molecular evolution of an Adh pseudogene in Drosophila 总被引:2,自引:0,他引:2
Sullivan DT; Starmer WT; Curtiss SW; Menotti-Raymond M; Yum J 《Molecular biology and evolution》1994,11(3):443-458
28.
Characterization of Ehrlich ascites tumor cell messenger RNA specifying ribosomal proteins by translation in vitro 总被引:2,自引:0,他引:2
We have examined the messenger RNA which codes for the ribosomal proteins in Ehrlich ascites tumor cells. Poly(A)-containing mRNA was isolated from polysomes and fractionated into 11 size classes whose average molecular weights were between 1.8 × 105 and 24 × 105. These mRNAs were used to direct protein synthesis in a fractionated translational system that was derived completely from Ehrlich ascites tumor cells. More than 90% of the ribosomal proteins which we could identify were coded for by mRNAs averaging in size between Mr = 180 × 103 and 320 × 103. The small size of these mRNAs indicates that the cytoplasmic mRNAs which specify the ribosomal proteins are monocistronic. We could detect the synthesis of 36 of 48 ribosomal reference proteins as well as 20 additional polypeptides which had characteristics similar to ribosomal protein. The ribosomal proteins were identified on the basis of their positive charge, small size, electrophoretic properties on two-dimensional polyacrylamide gels and chromatographic characteristics on carboxymethyl-cellulose. 相似文献
29.
Alteration of the Intracellular Energetic and Ionic Conditions by Mengovirus Infection of Ehrlich Ascites Tumor Cells and Its Influence on Protein Synthesis in the Midphase of Infection 下载免费PDF全文
Mengovirus infection of Ehrlich ascites tumor cells caused a change of the intracellular ATP concentration. It increased by 35% within the first 3 h postinfection and then declined to zero within the next 5 h. The decrease in the ATP concentration was due, at least in part, to leakage of ATP into the medium, where it could be demonstrated by the luciferin-luciferase assay. Gross leakage of ATP was observed at 4.5 h postinfection, concomitant with the production of the first intracellular, infectious virus particles. A similar concentration decrease was detected for Mg(2+), the polyamines, and K(+), whereas an increase in the Na(+) concentration was observed. The intracellular Mg(2+) concentration varied synchronously with the ATP level, rising by 16% during the first 3 h postinfection and then progressively falling to lower values in the late period of the infectious cycle. After an initial slight enhancement, the putrescine, spermidine, and spermine concentrations declined at about 1.5 h postinfection. Wherease the intracellular K(+) concentration increased by 17% during the first hour postinfection, the Na(+) concentration diminished by the same value within the same time period, leaving the internal ionic strength unchanged early in infection. Three hours after the beginning of virus infection, there was a rapid decline of K(+) and enhancement of Na(+) within the cell. These alterations of the intracellular energetic and ionic conditions seem to be, at least in part, responsible for the cessation of virus-specific protein synthesis in mengovirus-infected Ehrlich ascites tumor cells commencing 3 to 3.5 h postinfection. 相似文献
30.
When tested in a poly(U)-dependent polyphenylalanine synthesizing system and in a postnuclear supernatant, both derived from Ehrlich ascites tumor cells, 2(3),5-ADP did not affect chain elongation of polypeptide synthesis. In a cell-free system which was dependent on initiation and programmed by natural mRNA, however, the amino acid incorporating activity was suppressed to about 10% of the control in the presence of 1 mM 2(3),5-ADP. The inhibitor was shown not to interfere with the attachment of poly(U) to the small ribosomal subunit and with the formation of mRNA-80S ribosome complexes in a complete protein synthesizing system. The subsequent attachment of a 40S ribosomal subunit to the mRNA-80S ribosome complex and the formation of polysomes, however, was depressed by the inhibitor. The experimental results suggest that 2(3),5-ADP inhibits initiation-dependent protein synthesis between monosome formation and the formation of the first peptide bond(s). 相似文献