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51.
应用酶联免疫吸附试验检测马铃薯卷叶病毒 总被引:2,自引:0,他引:2
以辣根过氧化物酶标记马铃薯卷叶病毒抗体,采用双抗体夹心ELISA方法鉴定了马铃薯和洋酸浆的茎、叶、根及马铃薯块茎中的马铃薯卷叶病毒(Potato Leafroll Virus,PLRV),结果表明,对提纯的PLRV可测出的最低浓度为25ng/ml,当包被抗体浓度为40μg/ml、酶标记抗体稀释度为1/120时,可测出马铃薯茎、叶和根汁液中的PLRV,感染PLRV的洋酸浆茎、叶和根汁液的消光值,均比无病对照者高二倍以上,虽然感染PLRV的马铃薯休眠块茎维管束组织汁液的消光值高于无病毒对照,且脐部维管束组织消光值高于顶端,但测定打破休眠的感病块茎顶端维管束组织的阳性结果更为可靠和明显。 相似文献
52.
Immunoaffinity purified Sm/RNP antigens from buffalo and goat liver were studied to determine the role of RNA and proteins
towards the antigenicity of Sm and RNP antigens. A more direct approach using enzyme-linked immunosorbent assay on nylon beads
has been utilized to look into the problem. The effect of enzyme treatment and the role of RNA and protein fractions in influencing
antigenicity have been described. RNA seems to be involved in the maintenance of RNP specific polypeptides in suitable conformation
so as to keep them in solution. Removal of RNA leads to insolubilization of RNP specific polypeptides. Antibodies to Sm and
RNP antigens have been shown to cross react with poly A containing heterogeneous nuclear ribonucleoprotein with no cross reactivity
with thymus RNA or DNA. 相似文献
53.
The observations that liveMycobacterium leprae after entry into cultured peritoneal macrophages from mice, reduced the EA rosetting macrophages, have been exploited to
determine the minimum inhibitory concentration of diamino diphenyl sulphone and rifampicin. Diamino diphenyl sulphone showed
a minimum inhibitory concentration of 0.028 μg/ml and rifampicin 0.11μg/ml when given externally. However, there was accumulation of diamino diphenyl sulphone inside the macrophages. At an external
concentration of 0.028 μg/ml the concentration inside the macrophage was 0.5μg/ml. The minimum inhibitory concentration for diamino diphenyl sulphone in this assay system is higher by several folds and
that for rifampicin is slightly lower, than what is reported earlier with mice foot pad experiments. The minimum inhibitory
concentration reported in this assay system is quite close to what is observed forin vitro inhibition ofMycobacterium lufu with both the drugs 相似文献
54.
Using a specific radioimmunoassay for gonadotropin releasing hormone, the presence of gonadotropin releasing hormone like
material in the first trimester human placenta has been demonstrated. The material has been partially characterized using
carboxy methyl cellulose chromatography, high pressure gel permeation chromatography and reverse phase C18 high pressure liquid
chromatographic analysis. Analysis for bioactivity revealed that placental gonadotropin releasing hormone is much more active
than synthetic gonadotropin releasing hormone inin vitro rat pituitary lutinising hormone release assay.In vitro biosynthetic studies using labelled precursors and immunoaffinity chromatography indicated that first trimester human placenta
synthesizes gonadotropin releasing hormone like material. 相似文献
55.
Monoclonal antibodies were prepared against two species of Methanomicrobiaceae. Antibody 1A is specific for Methanospirillum hungatei strain JF1 and the determinant it recognizes is expressed on the surface of JF1 cells, where it is exposed and accessible to antibody. The determinant is found in a polypeptide (MW<12,000) in the sheath that covers the bacterial cell; it is not present in Methanospirillum hungatei strain GP1; and it is not expressed on the surface of whole cells of the other 24 methanogenic bacteria tested. It is therefore a marker of strain JF1, consequently, antibody 1A is potentially useful for tracking JF1 and fragments thereof in a variety of samples. Antibody 7A is specific for Methanogenium cariaci JR1c. It did not react with any other methanogen tested, not even with Mg. marisnigri or Ms. hungatei JF1, although these cross-react with Mg. cariaci if tested with polyclonal antisera. Therefore antibody 7A recognizes specifically a marker of Mg. cariaci JR1c.Abbreviations SIA
slide immunoenzymatic assay
- SDS-PAGE
sodium dodecylsulfate polyacrylamide gel electrophoresis 相似文献
56.
57.
Esmail K. Shubber David Jacobson-Kram Dr. Jerry R. Williams 《Cell biology and toxicology》1986,2(3):379-399
Seven antischistosomal drugs, two antimalarial drugs, and one antiamoebic drug were tested in all five Ames strains for induction of mutation, as well as for induction of cytotoxicity, inhibition of cellular progression, and the induction of sister chromatid exchanges in two cultured mammalian cell lines. We found that two agents shown to be negative in the Ames test were positive for sister chromatid exchange induction. Based on qualitative and quantitative evaluation, we find that all but three of the pharmaceuticals should be considered to be potential human carcinogens.Abbreviations AA
2-aminoanthracene
- 9AACC
9-aminoacridine
- AM
amoscanate
- BrdUU
bromodeoxyuridine
- CA
chloroquine diphosphate
- CHO
Chinese hamster ovary
- CQ
chloroquine
- DAPI
46-diamidino-2-phenylindole
- DHY
dehydroemetine
- DMSO
dimethyl sulfoxide
- EB
ethidium bromide
- FCS
fetal calf serum
- FN
4-fluoro-3-nitrophenyl azide
- HY
hycanthone
- ICP
inhibiting cell progression
- LU
lucanthone
- MEM
minimal essential medium
- 2NF
2-nitrofurantoin
- 4NPD
4-nitro-O-phenylenediamine
- NZ
niridazole
- OL
oltipraz
- OX
oxaminiquine
- PBS
phosphate buffered saline
- PQ
primaquine
- PZ
praziquantel
- SA
sodium azide
- SCE
sister chromatid exchange 相似文献
58.
Aerobic ferrisiderophore reductase assay and activity stain for native polyacrylamide gels 总被引:4,自引:0,他引:4
The reduction of ferric iron from microbial iron-binding compounds (siderophores) releases the iron from the siderophore so that it may be utilized by the microorganism. A method to detect aerobic ferrisiderophore reductase activity using ferrozine as a ferrous iron trap is shown to be applicable to cytoplasmic fractions from Rhodopseudomonas sphaeroides and four other different species of bacteria. The ferrisiderophore reductase uses reduced nicotinamide cofactors as reducing agents, and activity is stimulated by flavins. This assay has been adapted as a staining method to locate ferrisiderophore reductase activity in native polyacrylamide gels. 相似文献
59.
M Krieger 《Analytical biochemistry》1983,135(2):383-391
Pores formed in the membranes of animal cells by complexes of sterols and the polyene antibiotic amphotericin B can efficiently kill the cells. Thus, in the absence of exogenous sources of cholesterol, inhibitors of enzymes in the cholesterol biosynthetic pathway render cells resistant to amphotericin B. Preincubation of Chinese hamster ovary cells with compactin or 25-hydroxycholesterol, inhibitors of the synthesis of the key intermediate mevalonate, protected cells from amphotericin B killing and this protection was reversed by the addition of exogenous mevalonate. The ability of compactin to confer amphotericin B resistance on normal cells was abolished when cells were provided exogenous cholesterol by the receptor-mediated endocytosis of low density lipoprotein. Low density lipoprotein receptor-defective Chinese hamster ovary cells were not subject to this low density lipoprotein-dependent amphotericin B killing. Exogenous mevalonate did not prevent 4,4,10 beta-trimethyl-trans-decal-3 beta-ol, an inhibitor of mevalonate conversion to sterols, from protecting cells from amphotericin B. A simple two-step protocol in which cells are preincubated (15-24 h) with potential inhibitors and then treated (3-6 h) with amphotericin B was devised to provide a sensitive method for detecting direct (e.g., competitive) and regulatory inhibitors of cholesterol biosynthesis. This protocol may prove useful in detecting potential antihypercholesterolemia drugs and is currently being used to isolate mutants in receptor-mediated endocytosis. 相似文献
60.
A method is presented for the rapid enzymatic determination of acetate in spent bacterial culture supernatants. The assay is based on a previously published assay for acetate kinase [Bergmeyer et al. (1974) in Methods of Enzymatic Analysis (Bergmeyer, H. V., ed.), Vol. 1, pp. 425-426, Verlag Chemie-Academic Press, New York/London], and is sufficiently sensitive to detect acetate levels of 50 microM. The assay is cheaper than commercially available assays and is particularly useful for occasional use by laboratories not equipped for routine acetate analysis using gas chromatography. The application of the assay to the measurement of acetate in bacterial cultures is described, though it should also be applicable to other biological fluids and foodstuffs. 相似文献