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41.
42.
Characterization of WiDr: A human colon carcinoma cell line 总被引:1,自引:0,他引:1
P. Noguchi R. Wallace J. Johnson E. M. Earley S. O'Brien S. Ferrone M. A. Pellegrino J. Milstien C. Needy W. Browne J. Petricciani 《In vitro cellular & developmental biology. Plant》1979,15(6):401-408
Summary We describe the establishment and characterization of WiDr, a cell line derived from a human colon carcinoma. It produces
carcinoembryonic antigen in culture, and has a doubling time of 15 hr with plating efficiency of 51%. The HLA antigenic profile
and the allozyme genetic signature (composed of eight gene-enzyme systems) of WiDr cells are different from those of HeLa
cells. Furthermore, WiDr cells possess three marker chromosomes, again distinct from the HeLa marker chromosomes. Finally,
it is highly tumorigenic in four different xenogeneic animal models. Based on these studies, WiDr represents a useful model
cell line for tumor cell biology investigations. 相似文献
43.
E. Y. Lasfargues W. G. Coutinho A. S. Dion 《In vitro cellular & developmental biology. Plant》1979,15(9):723-729
Summary A human breast tumor cell line BT-474 derived from an invasive ductal carcinoma was experimentally infected in vitro with
a mouse mammary tumor virus from the RIII strain (RIII-MuMTV). The virus that replicated in the human cells was characterized
as a mouse virus by immunofluorescence, electron microscopy and the presence of a specific RNA-directed DNA polymerase. The
cells themselves were human as per the karyotype and isoenzyme migration patterns. It is concluded that human cells are susceptible
to the mouse mammary tumor virus and can, eventually, support its replication.
This work was supported by USPHS Grant CA-08515 from the National Cancer Institute and by NIH Contract N01-CP-81003. 相似文献
44.
Summary Two stable epithelial-like cell lines, the pig kidney strain (LLC-PK1) and a Wilms' tumor line (TuWi), previously established in other laboratories, were found to exhibit a number of properties
characteristic of kidney proximal tubular epithelium. Electron micrographs of LLC-PK1 monolayers revealed cells forming rosettes reminiscent of tubules. Numerous elongated microvilli and an amorphous basal laminar
material surrounded the cell membranes. Cell junctions were located between cell membranes at regions adjacent to the patent
lumens. Wilms' cells in culture were similar in appearance to the pig kidney cells; they exhibited numerous microvilli, a
thin basal laminar coating on the membrane, and desmonsomes between cells. No rosette formation was evident. Neither cell
line was found to produce extracellular reticulin fibers when grown in the presence ofl-ascorbic acid for 1 week. Absence of stainable reticulin in cell monolayer culture after ascorbicacid treatment has been
noted only in cell lines of apparent epithelial origin. Histochemically, both lines reacted positively for activities of a
number of enzymes found in high amounts in normal kidney tubular epithelium. Pig kidney cells were highly positive for γ-glutamyl
transpeptidase activity and moderately active for acid phosphatase and leucine aminopeptidase activities. Wilms' tumor cells
were markedly active for γ-glutamyl transpeptidase, 5′-nucleotidase, ATPase, glucose-6-phosphatase, and acid phosphatase activities.
These findings in conjunction with the ultrastructural observations indicate that these two lines in culture maintain many
of the properties typical of proximal kidney tubular epithelium. 相似文献
45.
Peter Adamietz Reinhard Bredehorst Helmuth Hilz 《Biochemical and biophysical research communications》1978,81(4):1377-1383
(3H)poly(ADP-ribose) synthesized from nuclei by incubation with (3H)NAD was released from protein by alkaline treatment and electrophoresed in dodecyl sulfate gels. Individual polymers up to at least 33 units were completely separated according to their chain length. Size distribution was visualized by fluorography of the gels, and quantified by radioactivity determination of sliced gels The method could be applied to crude nuclear extracts. It showed that nuclei of Ehrlich ascites tumor cells produced a poly(ADP-ribose) pattern distinctly different from that of rat liver nuclei. 相似文献
46.
Molecular changes in cell surface membranes resulting from trypsinization of sarcoma 180 tumor cells
John W. Huggins Robert W. Chestnut Norman N. Durham Kermit L. Carraway 《生物化学与生物物理学报:生物膜》1976,426(4):630-637
Sarcoma-180 tumor cells in culture or grown as an ascites form in the CD-1 mouse have been subjected to mild trypsinization procedures in order to study morphological and molecular changes resulting from proteolysis. The cells attached to a substratum become rounded within 20 min and most undergo cell division, but they do not detach from the substratum. Removal of trypsin permits the cells to go back to their original spindle shape over an 8–20 h period.Surface membranes were isolated from trypsinized ascites and cultured cells and subjected to dodecyl sulfate-acrylamide gel electrophoresis. Both cell types showed the same two kinds of changes in electrophoretic patterns. First, there was a loss of glycoproteins from both cell types, even though they show different complements of cell surface glycoproteins. Second, there is a loss of high molecular weight polypeptides, which have previously been suggested to play a role in membrane stabilization and cell shape. These results further implicate these polypeptides in the control of cell morphology and offer circumstantial evidence for transmembrane interactions of surface glycoproteins with the high molecular weight polypeptides as a factor in controlling cell morphology. 相似文献
47.
D. L. Fine L. O. Arthur L. J. T. Young 《In vitro cellular & developmental biology. Plant》1976,12(10):693-701
Summary Several cell culture factors were found to influence in vitro expression of mouse mammary tumor virus (MMTV) in the mouse
adenocarcinoma cell line Mm5mt/c1. Cells were propagated in a variety of commercially available cell culture media to which dexamethasone (DXM) was added as
a stimulator of MMTV production. Culture seeding density, culture medium type, and glucose concentration each influenced MMTV
production when expressed on a per cell basis. Maximum cell growth occurred in cultures grown in RPMI-1640 medium containing
insulin. Those media which provided good cell growth were not necessarily optimal for virus expression. Addition of insulin
did not stimulate MMTV synthesis although dexamethasone alone was stimulatory in all media used; however, maximum MMTV expression
was obtained when dexamethasone and insulin were used in concert. Equivalent levels of MMTV-specific cell membrane antigen,
MMTV-specific protein, and virus particles were produced at incubation temperatures of 32°, 34° or 37° C; however, higher
levels of virus-related RNA-dependent DNA polymerase (RDDP) activity were recovered from cultures incubated at 32° and 34°
C than at 37° C. Decreased levels of RDDP were attributed to enzyme thermolability at 37° C incubation.
Research sponsored by the National Cancer Institute under Contract No. N01-CO-25423 with Litton Bionetics, Inc., and Contract
No. N01-CP-33253 with the University of California. 相似文献
48.
49.
Jonathan W. Yewdell 《Molecular & cellular proteomics : MCP》2022,21(7):100230
In the 35 years since the revelation that short peptides bound to major histocompatibility complex class I and II molecules are the secret of the major histocompatibility complex–restricted nature of T-cell recognition, there has been enormous progress in characterizing the immunopeptidome, the repertoire of peptide presented for immunosurveillance. Here, the major milestones in the journey are marked, the contribution of proteasome-mediated splicing to the immunopeptidome is discussed, and exciting recent findings relating the immunopeptidome to the translatome revealed by ribosome profiling (RiboSeq) is detailed. Finally, what is needed for continued progress is opined about, which includes the infusion of talented young scientists into the antigen-processing field, currently undergoing a renaissance; thanks in part to the astounding success of T-cell–based cancer immunotherapy. 相似文献
50.