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141.
142.
Monensin blocks endocytosis of vesicular stomatitis virus 总被引:8,自引:0,他引:8
R Schlegel M Willingham I Pastan 《Biochemical and biophysical research communications》1981,102(3):992-998
Monensin inhibits the infection of mouse cells by Vesicular Stomatitis Virus (VSV). At low drug concentrations (0.5 μM), endocytosis of VSV is inhibited whereas viral binding is unaffected. Monensin may be useful for analyzing the internalization of other viruses as well as soluble ligands. 相似文献
143.
144.
Harry K. Kaya 《Journal of invertebrate pathology》1980,35(1):20-25
High pH values (>11.0) cause the dissolution of occlusion bodies of the granulosis virus (GV) of Pseudaletia unipuncta and subsequent inactivation of the virus within 24 hr. The GV is also inactivated within 48 hr by 0.04% formaldehyde. The GV is found in the intestinal lumen of infective third stage nematodes (dauer juveniles) of Neoaplectana carpocapsae when development occurs in GV-infected hosts. The GV in these dauer juveniles retains its infectivity even when the nematodes are placed into an alkaline solution with pH values of 11.1 or 12.1 or in 0.04% formaldehyde up to 336 hr. However, significant loss of infectivity of GV occurs when the nematodes are in formaldehyde but not at high pH values. The dauer juveniles are ensheathed by the second stage cuticle. This cuticle probably protects the GV in the intestinal lumen of the nematode from the high pH and formaldehyde. 相似文献
145.
Takeshi Kawarabata Masako Funakoshi Yoshinobu Aratake 《Journal of invertebrate pathology》1980,35(1):34-42
Occluded virions of the Bombyx mori nuclear polyhedrosis virus were efficiently liberated from polyhedra by dissolution with the silkworm gut juice. The liberated virions were purified by sucrose density gradient centrifugation and the bands of enveloped virions were observed in the gradients. There was no functional difference between the gut juice-liberated and the carbonate-liberated virions. Disruption of enveloped virions by the gut juice was observed, but the formation of nucleocapsids from the degradation of the occluded virions was not detected. High yields of the enveloped virions from the polyhedra dissolved by the gut juice was obtained by separating the virions through sucrose density gradient centrifugation immediately after the dissolution of the polyhedra. Many factors, e.g., rearing seasons, silkworm strains, and rearing conditions, affect the polyhedra-dissolving property of the larval gut juice. 相似文献
146.
Lois K. Miller Scott G. Franzblau Hugh W. Homan Leslie P. Kish 《Journal of invertebrate pathology》1980,36(2):159-165
A variant of the baculovirus, Autographa californica nuclear polyhedrosis virus, has been isolated in Idaho during an epizootic disease in a field population of A. californica. Genotypic characterization indicates that the virus is distinct from variants previously characterized. Analysis of five clones, derived by plaque purification in cell culture, indicates relative homogeneity of the original virus isolate. Further exploration of the factors involved in natural genetic variability of baculoviruses is appropriate. 相似文献
147.
148.
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
149.
E De Clercq A Billiau V G Edy K L Kirk L A Cohen 《Biochemical and biophysical research communications》1978,82(3):840-846
2-Fluoro-L-Histidine inhibits protein synthesis in various cell cultures, as measured by 3H-leucine incorporation. This histidine analog also inhibits the cytopathogenicity of a number of RNA and DNA viruses in primary and continuous cell cultures; it blocks the transformation of normal mouse (MO) cells by murine sarcoma virus, and partially suppresses the release of murine leukemia virus by a continuously infected mouse cell line (JLSV5). In human skin fibroblasts, it reduces the interferon-inducing capacity of poly(I)·poly(C). Inhibition of cell protein synthesis may be the common cause of the various effects. 4-Fluoro-L-histidine is essentially inert in all of the test systems examined. 相似文献
150.
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