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121.
Michele I. Van Dyke Susan L. Gulley Hung Lee Jack T. Trevors 《Journal of industrial microbiology & biotechnology》1993,11(3):163-170
Summary Several microbially produced biosurfactants were evaluated for their ability to remove hydrophobic compounds from soil. The biosurfactants produced byPseudomonas aeruginosa UG2 andAcinetobacter calcoaceticus RAG-1 displayed the best results, with recovery of [14C]hexachlorobiphenyl from soil slurries of 48.0 and 41.9%, respectively.P. aeruginosa UG2 produced higher levels of extracellular biosurfactants than four otherP. aeruginosa strains.P. aeruginosa UG2 culture filtrate containing biosurfactants enhanced the recovery of several other individual hydrocarbons and polychlorinated biphenyl compounds, as well as several hydrocarbons in a mixture, from soil. The results, suggest that biosurfactants produced byP. aeruginosa UG2 have the potential for remediation of hydrophobic pollutants in soil environments. 相似文献
122.
Niraj Shrestha Pallavi Chaturvedi Xiaoyun Zhu Michael J. Dee Varghese George Christopher Janney Jack O. Egan Bai Liu Mark Foster Lynne Marsala Pamela Wong Celia C. Cubitt Jennifer A. Foltz Jennifer Tran Timothy Schappe Karin Hsiao Gilles M. Leclerc Lijing You Christian Echeverri Catherine Spanoudis Ana Carvalho Leah Kanakaraj Crystal Gilkes Nicole Encalada Lin Kong Meng Wang Byron Fang Zheng Wang Jin-an Jiao Gabriela J. Muniz Emily K. Jeng Nicole Valdivieso Liying Li Richard Deth Melissa M. Berrien-Elliott Todd A. Fehniger Peter R. Rhode Hing C. Wong 《Aging cell》2023,22(5):e13806
123.
Lawrence Cris W.; Little Pamela A.; Little Brian W.; Glushka John; van Halbeek Herman; Alhadeff Jack A. 《Glycobiology》1993,3(3):249-259
The N-glylycans have been removed by peptide-N-glycosidase F(PNGase F) from purified human non-secretory RNases derivedfrom kidney, liver and spleen. The spleen RNase was purifiedby two procedures, one of which did not include the usual acidtreatment step (0.25 M H2SO4, 45 min, 4C), to determine ifacid treatment alters the carbohydrate moieties. TheN-glycansof the RNases were fractionated by Bio-Gel P-4 chromatographyand analysed by 600 MHz 1H-NMR spectroscopy and electrospraymass spectrometry. All four non-secretory RNase preparationscontained the following structures: The relative amounts of the trisaccharide, pentasaccharide andhexasaccharide appeared to vary slightly in the different tissueRNases. The overall results indicate: (i) that acid treatmentduring purification does not alter the N-glycans of non-secretoryRNases; (ii) that the N-glycans from kidney, liver and spleennon-secretory RNases are very similar, if not identical, toone another, but different from the N-glycan structures reportedfor secretory RNase. N-glycans non-secretory RNases 相似文献
124.
Michael A. Poss Joyce A. Reid Charles A. Free W. Lynn Rogers Helen Weber Denis E. Ryono Tamara Dejneka Jack M. DeForrest Thomas L. Waldron Russell J. Brittain Harold N. Weller Maria P. Cimarusti Edward W. Petrillo 《Bioorganic & medicinal chemistry letters》1993,3(12):2739-2744
The syntheses and pharmacological activity of a series of diol sulfonamides which function as inhibitors of human renin are described. The most potent compound in this series, compound 20 (SQ 33,800), is a subnanomolar inhibitor of human renin (IC50 = 0.35 × 10−9 M). 相似文献
125.
Michael A. Simpkins David E. Withrow Jack C. Cesarone Peter L. Boveng 《Marine Mammal Science》2003,19(4):791-805
We monitored the haul-out behavior of 68 radio-tagged harbor seals ( Phoca vitulina ) during the molt season at two Alaskan haul-out sites (Grand Island, August-September 1994; Nanvak Bay, August-September 2000). For each site, we created a statistical model of the proportion of seals hauled out as a function of date, time of day, tide, and weather covariates. Using these models, we identified the conditions that would result in the greatest proportion of seals hauled out. Although those "ideal conditions" differed between sites, the proportion of seals predicted to be hauled out under those conditions was very similar (81.3% for Grand Island and 85.7% for Nanvak Bay). The similar estimates for both sites suggest that haul-out proportions under locally ideal conditions may be constant between years and geographic regions, at least during the molt season. 相似文献
126.
Timothy Wachs Robin L. Sheppard Jack Henion 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,685(2):548
A simple self-aligning liquid junction-electrospray interface for coupling a capillary electrophoresis (CE) system to an atmospheric pressure ionization (API) mass spectrometer (CE-MS) was developed. In contrast to previous liquid junction interfaces, the self-aligning liquid junction interface simplifies the precise alignment of the CE capillary and the sprayer needle and uses a positive make-up flow. Several capillary CE-MS applications were run using both the self-aligning liquid junction interface and the widely used sheath flow interface for comparison purposes. The electrospray stability of the self-aligning liquid junction interface is consistently better even when non-volatile electrolyte solutions are used. At first, some band broadening was obtained with the self-aligning liquid junction interface. Experiments with different CE buffer systems suggested that this band broadening was caused by the materials used in constructing the interface. By using a more inert material for the sprayer needle, the self-aligning liquid junction exhibits excellent electrophoretic resolution, comparable sensitivity, and higher signal-to-noise ratios when run under the same conditions as the sheath flow interface. 相似文献
127.
Human and animal mesenchymal progenitor cells from bone marrow: Identification of serum for optimal selection and proliferation 总被引:14,自引:0,他引:14
Donald P. Lennon Stephen E. Haynesworth Scott P. Bruder Neelam Jaiswal Arnold I. Caplan 《In vitro cellular & developmental biology. Animal》1996,32(10):602-611
Summary An undifferentiated subset of cells within the stromal cell population of bone marrow in postnatal mammals retains the capacity
to differentiate along osteogenic, adipogenic, fibroblastic, and chondrogenic lines. These cells, which are referred to as
mesenchymal stem cells (MSCs), can be maintainedin vitro and expanded in number through a process of subculturing. MSCs are maintained in culture in medium supplemented with 10%
fetal bovine serum (FBS). It is believed that certain, as yet unidentified, serum components play critical roles in the attachment
and proliferation of MSCs. Commercially available FBS is poorly characterized and may vary in composition and quality from
lot to lot. This study describes a method for the selection of lots of FBS that best support maintenance of the undifferentiated
state, mitotic expansion of MSCsin vitro, and retention of multilineage developmental potential in response to appropriate cues. 相似文献
128.
Vera V. Lozovaya Ximing Luo Jack M. Widholm 《In vitro cellular & developmental biology. Plant》1996,32(4):295-298
Summary Seven suspension-cultured lines of five different species (Amaranthus powellii Datura innoxia, Glycine max, Gossypium hirsutum, andNicotiana tabacum × Nicotiana glutinosa fusion hybrid), which had been grown under photomixotrophic conditions, were placed under heterotrophic conditions (darkness
and media with 3% sucrose or starch) where the chlorophyll levels declined to near zero. After three transfers over a 70-d
period, the cells were placed back into photomixotrophic or photoautotrophic conditions where regreening occurred rapidly
and continued growth was observed. This rapid adaptation to photosynthetic conditions contrasts with the original initiation
process for these cultures, which required many months and an apparent selection since many of the original cells died. Thus,
these seven photosynthetic cell suspension cultures appear to be different from the original cultures due possible to genetic
or adaptive changes. 相似文献
129.
Dimitri S. Monos Eszter Czanky Santa J. Ono Susan F. Radka Dietmar Kappes Jack L. Strominger 《Immunogenetics》1995,42(3):172-180
cDNAs coding for the HLA class II DR and DQ and chains of the diabetogenic haplotypes DR3 and DR4 were introduced into a mammalian expression vector and transfected into L-cell mouse fibroblasts to produce cells expressing individual human class II molecules. Stable L transfectants were generated expressing each of the DR or DQ isotypes of the cis-encoded and chains of the DR3 or DR4 haplotypes, as well as the trans-encoded and chains of the DQ molecules of the two haplotypes. However, isotype mismatched combinations (DR/DQ or DQ/DR) did not result in any stable transfectants. The stable DQ L-cell transfectants obtained, along with homozygous B-cell lines expressing the DQ2 and DQ8 specificities, were tested against a large panel of twentyone anti-HLA class II monoclonal antibodies (mAbs). Their unusual reactivity patterns are described including the failure of most pan-DQ mAbs to react with all DQ expressing L-cell transfectants. Interestingly, some mAbs react with certain heterodimers expressed on B-LCL but fail to recognize the same heterodimers expressed on the transfectants. This is suggestive of minor structural modifications that class II molecules undergo depending on the cells they are expressed on.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number U07848. The name DQB1
*
0202 was officially assigned by the WHO Nomenclature Committee in April 1994. This follows the agreed policy that, subject to the conditions stated in the most recent Nomenclature Report (Bodmer et al. 1992), names will be assigned to new sequences as they are identified. Lists of such new names will be published in the following WHO Nomenclature Report 相似文献
130.
The cut locus encodes a homeobox protein that is localized in the nuclei of a variety of tissues and is required for proper morphogenesis of those tissues. Cut protein is required in embryonic and adult external sensory organs, where its absence results in conversion of the organs to chordotonal organs. Expression of cut also occurs in the Malpighian tubules, spiracles, central nervous system, and a number of other tissues. Gypsy transposon insertions upstream of the cut promoter block expression in subsets of these tissues. The effect of the gypsy insertions is polar, with those farthest from the promoter affecting the fewest tissues. The hypothesis that gypsy insertions block a series of tissue-specific enhancer elements that are distributed over a region of 80 kb upstream of the promoter predicts the location of the enhancers for cut expression in each of the tissues in which it is active in embryos. DNA fragments from this region drive expression of a reporter gene in each of the embryonic tissues in which endogenous cut gene is expressed. Each tissue has its own enhancer, and none of the enhancers require the activity of the endogenous cut gene to function. 相似文献