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991.
The Use of Ferritin Labelled Antibodies in the Location of Spore and Vegetative Antigens of Bacillus cereus 总被引:5,自引:1,他引:4
P. D. Walker Ann Baillie R. O. Thomson Irene Batty 《Journal of applied microbiology》1966,29(3):512-518
S ummary . Ferritin labelled antibodies have been used to detect the presence of vegetative antigens in spores. The specificity of the labelled antibodies was demonstrated. Vegetative antigens were found along the core or cortical membrane in spore disintegrates, and after germination along the developing vegetative cell wall. The implications of these results are discussed in relation to morphological studies of ultra-thin sections. 相似文献
992.
Adelaida Sánchez Silvia Cenani Irene von Lawzewitsch 《Primates; journal of primatology》1991,32(1):93-103
A histochemical and immunocytochemical study was performed to describe the cellular localization of four hormones in pancreatic
tissue of the Callithricidae and Cebidae families belonging to Platyrrhini monkeys. Insulin, somatostatin, glucagon, and gastrin
immunoreactive cells were detected in the pancreatic islets at light microscope level. Beta cells (insulin positve) were distributed
in a peripheral mantle or in irregular clusters in a polar region of the islet. Also little groups (small islets) from three
to six beta cells distributed in the pancreatic stroma were observed in all the species. A constant feature was the presence
of neuroinsular complexes. The alpha cell population was composed of orangeophiles or phloxinophile cells and presented an
heterogeneous composition as the result of their granular type (difference in immunocytochemical affinity). Alpha 1 cells
(somatostatin) were scattered between the other cells or in the periphery of the islets, while alpha 2 cells (glucagon) were
distributed in three different ways: (1) occupying polar positions; (2) disseminated in small groups; or (3) arranged in cord-like
disposition. One or two G cells (gastrin) were found in few islets.
This work was supported by grants from the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Estudio Histológico
Comparado del Sistema de Glándulas Endócrinas (EHIGE) program.
Postgraduated Fellow from CONICET
Established Investigator and Director of EHIGE. 相似文献
993.
Single-Step Purification and Biological Activity of Human Nerve Growth Factor Produced from Insect Cells 总被引:3,自引:3,他引:0
Stephen Buxser Steven Vroegop Douglas Decker Jessica Hinzmann Roger Poorman Darrell R. Thomsen† Mike Stier† Irene Abraham Barry D. Greenberg† Nicole T. Hatzenbuhler Mary Shea Kim A. Curry† Che-Shen C. Tomich† 《Journal of neurochemistry》1991,56(3):1012-1018
Human nerve growth factor (NGF) was cloned and engineered for expression in a baculovirus-infected Spodoptera frugiperda (SF-9) insect cell system. Culture supernatants contained 2-3 mg/L of recombinant human NGF. The human NGF produced by this system was purified to apparent homogeneity with a single-step affinity chromatography procedure using a high-affinity monoclonal antibody originally raised against murine NGF. The purification procedure yielded 1-2 mg of pure, human NGF per liter of culture supernatant; i.e., approximately 60% recovery of the human NGF originally released into the culture medium. Although the gene transfected into the SF-9 cells coded for pro-NGF, the NGF recovered after purification was greater than 95% fully processed, mature protein. The KD for the affinity of the pure, recombinant human NGF for NGF receptor in PC12 membranes is 0.20 +/- 0.05 nM. Activation of neurite outgrowth in PC12 cells occurs with ED50 values of 85 +/- 20 pM and 9.6 +/- 1.5 pM for a 3-day primary response and a 1-day secondary response, respectively. The pure, recombinant human NGF also stimulates a significant increase in dopamine content of PC12 cells with an ED50 of 5.8 +/- 2.7 pM. These binding and biological activation properties are consistent with values observed using murine NGF purified from submaxillary glands. 相似文献
994.
N. Maggiano L. M. Larocca M. Piantelli F. O. Ranelletti L. Lauriola R. Ricci A. Capelli 《The Histochemical journal》1991,23(2):69-74
Summary A full-length cDNA clone encoding the constant region of T cell receptor chain was labelled by random priming DNA with digoxigenin-dUTP. The probe was used to estimate the relative amount of the receptor chain mRNA byin situ hybridization on frozen sections from human thymus and lymph nodes. The hybridization was visualized in blue using an anti-digoxigenin antibody conjugated with alkaline phosphatase and a subsequent enzyme-catalysed colour reaction. The distributions of the signal in tissue sections were as expected. Moreover, labelled cells showed hybrids both in the cytoplasm and in the nucleus, and strongly and weakly stained cells were clearly distinguishable. The results indicate that this method ofin situ hybridization should be useful in the detection of specific mRNA in frozen sections. 相似文献
995.
Irene Popiel Donato Cioli David A. Erasmus 《International journal for parasitology》1984,14(2):183-190
Popiel I., Cioli D. and Erasmus D. A. 1984. The morphology and reproductive status of female Schistosoma mansoni following separation from male worms. International Journal for Parasitology14: 183–190. Sexually mature females of Schistosoma mansoni were separated from their male partners and surgically transferred to Nile rats (Arvicanthis niloticus). Over a period of 35 days there was a significant decrease in size of these worms and regression of the reproductive system took place. Electron microscope observations of the vitelline gland and ovary provided details of and a time scale for the regressive changes which took the form of a cessation of cell differentiation and turnover, together with extensive cell death. Survival of cells within these organs was restricted to the undifferentiated cells and by day 35 the worms resembled immature females. It is concluded that regression of the female reproductive system was the result of discontinued male stimulation.The nature and implications of the obligatory relationship between male and female S. mansoni are discussed. 相似文献
996.
Irene Gander Renate Foeckler Lars Rogge Michael Meisterernst Rudolf Schneider Ronald Mertz Friedrich Lottspeich Ernst-Ludwig Winnacker 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1988,951(2-3)
The paper describes a potent purification method, preparative gel retention, for the purification of sequence-specific DNA-binding proteins. This procedure exploits the sequence-specific DNA-binding affinity of such proteins for their enrichment, comparable to recognition site DNA affinity chromatography. The method was employed to obtain a pure preparation of nuclear factor I (NFI) from porcine liver from which sequences of partial peptides could be obtained. Oligonucleotide probes derived from these amino-acid sequences were used to identify genomic and cDNA clones of NFI. 相似文献
997.
A study, conducted with 20 isolates of Microsporum ferrugineum and 12 isolates of Trichophyton soudanense, revealed that some of the discrepancies in the literature regarding their characteristics and differentiation were due to methodology, strain variation and the use of an insufficient number of isolates. We found all isolates of T. soudanense to be urease negative and gelatinase positive (usually by the first week); to produce brown to black colonies on Lowenstein-Jensen medium; to rapidly decompose casein and more slowly tyrosine; to grow well or better at 37°C as compared to room temperature; to produce reflexive branching on cornmeal Tween agar and abundant microconidia on casero medium and to exhibit no sexual reaction with either mating type of Arthroderma simii. All but one isolate demonstrated restricted growth on lactose agar and only three isolates perforated hair.In contrast, we found 18 of 20 isolates of M. ferrugineum to be urease positive in urea broth (most isolates were negative on urea agar); all produced light-colored colonies on Lowenstein-Jensen medium; spreading colonies on lactose agar and failed to perforate hair in vitro or to produce reflexive branching. Most isolates manifested poorer to no growth at 37°C compared to room temperature and all but one failed to decompose casein and tyrosine. A few strains produced macroconidia and/ or microconidia on casero medium and some reacted sexually with A. simii (a) or (–) mating type. Gelatin hydrolysis was variable.We suggest the following key tests to differentiate M. ferrugineum from T. soudanense: urease activity in urea broth; colony color on Lowenstein-Jensen medium; growth on lactose agar; growth at 37° C compared to room temperature; presence of reflexive branching on cornmeal Tween agar. 相似文献
998.
Irene Szumiel Danuta Włodek György Lustyik 《Radiation and environmental biophysics》1984,23(4):255-267
Summary We examined the response of L5178Y-S (radiosensitive, LY-S) and L517SY-R (radioresistant, LY-R) lymphoblasts to X-irradiation with concomittant treatment with divalent cation ionophore, A23187 (3 h or 5 h, 5 µg/ml). Cells treated with A23187 alone progressed through the cell cycle more slowly than the untreated cells and their cloning efficiency was reduced. In both cell strains the ionophore prolonged duration of the postirradiation mitotic delay. Radiation-induced inhibition of DNA synthesis was reversed by A23187 in LY-S but not in LY-R cells.Cells subjected to the ionophore treatment survived X-irradiation in almost the same way as untreated cells, as if the effect of A23187 treatment were reversed by irradiation. There was also a reversion in the ion content: A23187 caused a marked increase in Na+ content and a decrease in K+ content, irradiation itself did not change the ion content, whereas in the A23187-treated cells it restored almost the same pattern as that found in the control cells. We found less Mg2+ ions in LY-S cells after treatment with A23187 and A23187 + X than in LY-R cells, in relation to untreated (control) cells. These observations point to the possible importance of ion transport for recovery from radiation damage. 相似文献
999.
1000.
Neil Garton Nick Bailey Mark Bamford Emmanuel Demont Irene Farre-Gutierrez Gail Hutley Gianpaolo Bravi Paula Pickering 《Bioorganic & medicinal chemistry letters》2010,20(3):1049-1054
We report the identification of a novel biaryl template for H+/K+ ATPase inhibition. Evaluation of critical SAR features within the biaryl imidazole framework and the use of pharmacophore modelling against known imidazopyridine and azaindole templates suggested that the geometry of the molecule is key to achieving activity. Herein we present our work optimising the potency of the molecule through modifications and substitutions to each of the ring systems. In particular sub-micromolar potency is achieved with (4b) presumably through a proposed intramolecular hydrogen bond that ensures the required imidazole basic centre is appropriately located. 相似文献