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481.
CJ Cooksey 《Biotechnic & histochemistry》2018,93(3):211-219
The long history of eosin Y, eosin B and the methyl and ethyl eosins is recounted as well as their synthesis, the variety of their molecular species and some of the myriad applications of these dyes. Chromatographic techniques are described that reveal the purity or lack of it in commercial samples. Toxicological studies are discussed that suggest that the eosins are virtually non toxic, but efforts to remove them from the environment imply that there may be some risk. 相似文献
482.
The association between a large molecular mass plasmid and virulence in a strain of Salmonella pullorum 总被引:9,自引:0,他引:9
Eight strains of Salmonella pullorum isolated from epidemiologically independent cases of pullorum disease (bacillary white diarrhoea) in young chickens possessed at least one large molecular mass plasmid in addition to smaller molecular mass plasmids. The 85 kb large plasmid, designated pBL001, of one of these strains was 'tagged' with an ampicillin resistance marker by the insertion of transposon Tn3. The plasmid was eliminated by passage in nutrient broth containing acridine orange. It was reintroduced into the strain from which it had been eliminated by mobilization using the F plasmid. Following oral inoculation of newly hatched Rhode Island Red chickens, the parent strain produced a high level of mortality (71%) with characteristic signs of pullorum disease. Following intramuscular inoculation of chickens of the same age, the bacterial LD50 was (log10 c.f.u.) 3.38 +/- 0.43 (mean +/- SEM). The derivative lacking pBL001 produced no mortality or morbidity when inoculated orally and the bacterial LD50 value increased to (log10 c.f.u.) 5.54 +/- 0.28. This increase was statistically significant (chi 2 = 13.6, P less than 0.01). Reintroduction of pBL001 restored virulence as gauged by oral inoculation of chickens (62% mortality) and by the intramuscular bacterial LD50 value (log10 c.f.u. = 3.78 +/- 0.25). These values were not significantly different to those produced by the parent strain (chi 2 = 0.59, P = 0.4 and chi 2 = 0.66, P = 0.5, respectively). Following oral inoculation, the pBL001-cured derivative was less invasive than the parent strain and following intramuscular inoculation it persisted for a shorter period than the parent strain in the liver, spleen and the leg muscle into which it had been inoculated. In addition, the parent strain, but not the pBL001-cured derivative, localized in large numbers in the myocardium where it produced lesions typical of pullorum disease. Both the parent strain and the pBL001-cured derivative were serum resistant in the presence of rabbit serum and grew equally well in chick serum and broth. 相似文献
483.
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485.
E. A. Kingsley Teresa E. Carter Kevin D. Barrow Pamela J. Russell 《Cancer immunology, immunotherapy : CII》1995,41(5):317-323
A monoclonal antibody, BLCA-8, was raised against the human bladder cancer cell line, UCRU-BL-17CL. By flow cytometry and
immunoperoxidase staining, this antibody was found to possess high specificity for bladder tumours, some reactivity with fetal
tissues, and no reactivity with normal bladder, or any normal or malignant tissue. This high specificity and the stability
of the antigen to the urinary environment suggest that BLCA-8 may have potential for use as an anti-bladder-cancer therapeutic
agent. By thin-layer chromatography and autoradiography, BLCA-8 was found to bind four components within the neutral lipid
fraction of a bladder cancer cell line, UCRU-BL-17/23α. These components had R
F values of 0.22, 0.16/0.15 (doublet), 0.12 and 0.08, and migrated below globoside, indicating the presence of more than four
sugars. By enzyme-linked immunosorbant assay and thin-layer chromatography it was found that the binding of BLCA-8 to the
lipid extract was increased by both mild alkaline hydrolysis and enzymatic treatments, indicating that adjacent phospholipids
and glycolipids interfere with the accessibility of the antibody-binding site. Full biochemical characterisation of the BLCA-8
antigen is currently underway.
Received: 24 April 1995 / Accepted: 11 July 1995 相似文献
486.
487.
Determination of hopanoid levels in bacteria using high-performance liquid chromatography 总被引:1,自引:0,他引:1
A reverse-phase HPLC method to detect and quantify levels of hopanoids in bacteria has been developed. Chromophores have been introduced by derivatization and the levels of the C35 hopanoids and their conjugates can be measured in bacterial lipid extracts down to picomole levels. Some structural variations of the complex lipids were detected after derivatization and were easily purified using the same HPLC system. Zymomonas mobilis and Rhodospirillum rubrum extracts were examined using this system and different structural examples of the lipids were detected. The relative levels of the different triterpenes were very dependent on the growth conditions. 相似文献