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41.
Effects of age and physical performance capacity on distribution and composition of high-density lipoprotein subfractions in men 总被引:1,自引:0,他引:1
Ingrid Frey Aloys Berg Manfred W. Baumstark Klaus-Günther Collatz Josef Keul 《European journal of applied physiology and occupational physiology》1990,60(6):441-444
The influences of age and maximal aerobic capacity (VO2max) on serum lipoproteins with special regard to the concentration, composition and distribution of high density lipoprotein (HDL) subfractions were investigated in 51 healthy males of different characteristics: younger than 35 years, untrained (n = 14, mean age 28.2 years, SD 6.0; VO2max, 47.9 ml.kg-1.min-1, SD 5.8) and trained (n = 11, mean age 27.9 years, SD 4.3; VO2max, 61.1 ml.kg-1.min-1, SD 5.1), older than 50 years untrained (n = 14, mean age 58.9 years, SD 5.9, VO2max, 29.3 ml.kg-1.min-1, SD 5.3) and trained (n = 12, mean age 59.3 years, SD 7.2, VO2max, 45.7 ml.kg-1.min-1, SD 7.7). The fasting-state serum concentrations of total cholesterol, tri-acylglycerol and lipoprotein-cholesterol were measured. The HDL-subfractions were separated by density (rho) gradient ultracentrifugation. Concentrations of cholesterol, cholesterylester, tri-acylglycerol, phospholipids, apolipoprotein (apo) A-I and A-II were measured in the subfractions HDL2b: rho = 1.063-1.100 g.ml-1; HDL2al: rho = 1.00-1.110 g.ml-1; HDL2a2: rho = 1.110-1.150 g.ml-1; HDL3: rho = 1.150-1.210 g.ml-1. Elderly untrained subjects showed increased serum concentrations of total-, very low- and low density lipoprotein-cholesterol and elevated tri-acylglycerol levels. The HDL-cholesterol concentration was decreased, due to reduced concentrations of HDL2-subfractions. Significant changes in the composition of HDL2-subfractions were found in elderly untrained subjects. The HDL2-subfractions had more protein, a decreased apoA-I:A-II ratio and less phospholipids in comparison to HDL2-subfractions from younger untrained and trained, and elderly trained subjects.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
42.
Bacterial translocation is defined as the passage of viable bacteria from the gastrointestinal tract to the mesenteric lymph nodes and other extraintestinal sites. The translocation rate of a newly described species of indigenous bacteria,Lactobacillus murinus, was compared with the translocation rates of indigenousLactobacillus acidophilus and nonindigenousSalmonella enteritidis. Groups of germfree or antibiotic-decontaminated, specific pathogen-free mice were monoassociated with each of these bacterial strains and tested at various intervals for translocation to the mesenteric lymph nodes. The translocation rates of the various bacteria expressed in decreasing order as the numbers of translocating bacteria per gram mesenteric lymph node wereS. enteritidis, L. murinus, andL. acidophilus. The degree of histologic damage to the gastrointestinal mucosa after monoassociation with these strains followed the same pattern. Thus,L. murinus translocates from the GI tract at a surprisingly high rate for an indigenous bacterial strain, and its translocation appears to be associated with mucosal alterations. 相似文献
43.
A fast method for the screening of a large number of immobilized dyes for the purification or binding of proteins called dye-ligand centrifugal affinity chromatography, is described. The ease and speed of this method is demonstrated by screening 65 immobilized dyes for the binding of purified goat IgG. Two immobilized dyes (Drimarene Blue K-R and Drimarene Rubine R/K-5BL) with a high affinity for goat IgG were found to bind specifically the Fc-fragment of the IgG. 相似文献
44.
S. Bissbort H. W. Hitzeroth D. P. du Wentzel C. W. Van den Berg H. Senff T. F. Wienker K. Bender 《Human genetics》1988,79(3):289-290
Summary We describe a new rare allele for esterase D (EsD) occurring in a Portuguese family with retinoblastoma in two generations. 相似文献
45.
Indomethacin inhibits cholera toxin-induced cyclic AMP accumulation in Chinese hamster ovary cells 总被引:1,自引:0,他引:1
Abstract Indomethacin was examined for its capacity to inhibit increases in adenosine-3',5'-monophosphate (cAMP) concentrations in Chinese hamster ovary (CHO) cells treated with cholera toxin. When added to the culture medium 1 h prior to cholera toxin (100 ng/ml), indomethacin (500 μg/ml) exhibited maximum protection against the typical increase in cAMP. Application of indomethacin at the same time as cholera toxin or up to 3 h after the toxin progressively decreased the drug's capacity to block further increases in cAMP. The drug appeared to block adenylate cyclase activity because addition of forskolin to drug-treated cells did not elicit a cAMP response. Binding of 125 I-labeled cholera toxin to indomethacin-treated cells was also reduced by at least 50%. These data indicate that indomethacin's inhibitory effect on cAMP formation in cholera toxin-treated cells could be explained by its capacity to alter adenylate cyclase activity and cholera toxin binding. 相似文献
46.
Abstract Ibuprofen, an inhibitor of prostaglandin synthesis in eukaryotic cells, was shown to inhibit the accumulation of 3',5'-cyclic adenosine monophosphate (cyclic AMP) in Chinese hamster ovary (CHO) cells exposed to cholera toxin. The inhibition was dose dependent, with a dose of 100 μg/ml reducing the cholera toxin response by approximately 50%, and maximal inhibition was observed when the drug was applied to the cells simulataneously with or 1 h before the toxin. Although ibuprofen also inhibited adenylate cyclase stimulation by forskolin, suggesting a nonspecific effect, the drug had no effect on cholera toxin-induced cyclic AMP accumulation when added to the culture medium 15 min or more after the toxin. 相似文献
47.
Summary We present a method that allows positive selection and rapid analysis of mutations in Enterobacteriaceae. Mutations are detected in a 2630 bp selection cartridge inserted in two different bacterial mutlicopy plasmid vectors. Spontaneous mutations in Escherichia coli, Enterobacter cloacae and Citrobacter freundii include insertions, deletions and point mutations. The small size of the target sequence facilitates rapid analysis of DNA rearrangements by cleavage with restriction enzymes and of any type of mutation by DNA sequence analysis. While in E. coli insertions of the mobile elements IS1, IS2 and IS5 were readily found, insertions of putative new transposable elements were detected in Enterobacter cloacae. The selection cartridge can thus serve as a tool for studying the spectrum of insertion mutations in Enterobacteriaceae and probably other Gramnegative bacteria, and the dependency of this spectrum on physiological and environmental factors and the host's genetic background can be investigated. 相似文献
48.
Selection of DNA binding sites by regulatory proteins 总被引:15,自引:0,他引:15
49.
50.
The m gamma delta-1 element, a small gamma delta (Tn1000) derivative useful for plasmid mutagenesis, allele replacement and DNA sequencing. 总被引:9,自引:0,他引:9
C M Berg N B Vartak G Wang X Xu L Liu D J MacNeil K M Gewain L A Wiater D E Berg 《Gene》1992,113(1):9-16
Transposon gamma delta (Tn1000), a 6-kb member of the Tn3 family, is widely used for plasmid mutagenesis. A 1.8-kb derivative of gamma delta was constructed that contains the kan gene from Tn5 and the resolution (res) site from gamma delta cloned between 40-bp inverted repeats of gamma delta's delta (delta) end. This element, named m gamma delta-1, lacks the genes encoding transposase and resolvase, and therefore depends on its host to supply transposition and resolution functions. Thus, in strains lacking gamma delta, m gamma delta-1 will not transpose. The m gamma delta-1 element is shown to be useful for mutagenesis of plasmids, DNA sequencing, and allele replacement (in Streptomyces avermitilis). 相似文献