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排序方式: 共有1210条查询结果,搜索用时 281 毫秒
11.
Rita Businaro Evandro Fioretti Lorenzo Fumagalli Gennaro Citro Gabriella De Renzis Franca Ascoli 《The Histochemical journal》1988,20(4):187-193
Summary In addition to bovine pancreatic trypsin inhibitor (BPTI), three BPTI-related molecular forms (isoinhibitors I, II and III) were isolated from bovine lung by affinity chromatography on immobilized trypsin and subsequently purified by Fast Protein Liquid Chromatography. These inhibitors are identical to the isoinhibitors previously isolated from bovine spleen. Their localization in bovine lung was studied by immunohistochemical techniques, using two different immunoglobulin preparations, selectively recognizing BPTI or the other molecular forms.BPTI-related immunoreactivity was found to be restricted to isolated cells, often identified as mast cells by Toluidine Blue staining. In contrast, isoinhibitor-related immunoreactivity, which also occurs in the mast cells, is present in a number of other cell types. These types include: (i) the smooth muscle cells of different calibre vessels, (ii) the ciliated cells of the bronchial epithelium and the related mucus, and (iii) many cells at alveolar level.Comparison of these data with previous results obtained for bovine spleen suggest multiple physiological roles for these inhibitors. 相似文献
12.
Isolation and characterization of an extrachromosomal element from Nocardia mediterranei 总被引:10,自引:0,他引:10
Strain LBG A3136 of Nocardia mediterranei (ETH Collection) was found to contain a low-copy-number covalently closed circular extrachromosomal element, pMEA 100, which could only be isolated from mycelium grown on agar plates. pMEA 100 could not be isolated from the closely related strain ATCC 13685. Hybridization experiments showed that pMEA 100 is present in strain LBG A3136 in the free as well as in the integrated form whereas in strain ATCC 13685 only an integrated form was detected. Excision and reintegration in strain LBG A3136 seemed to be site specific. pMEA100 was found to be self-transmissible, eliciting the lethal zygosis phenotype, and is possibly involved in fertility in N. mediterranei. 相似文献
13.
Edgardo R. A. Moretti Beatriz Basso Elsa Vottero-Cima 《The Journal of eukaryotic microbiology》1985,32(1):150-153
ABSTRACT Exoantigens of Trypanosoma cruzi were produced in experimentally infected BALB/c mice. The exoantigens were detected by the counterimmunoelectrophoresis method (CIE), with antisera raised in rabbits by immunization with total homogenates of culture forms of ***T. cruzi in plasma from ***field animals obtained by centrifugation and filtration. Control experiments indicated that exoantigens are not somatic components of T. cruzi leaked during the preparative procedure. Exoantigens were detected in male and female mice, 11-90 days old, between 6 and 60 days of infection, and in all mice with patent parasitemia. After 13 days of infection, mice developed antibodies to exoantigens; by CIE up to three populations of antibodies were revealed in different groups of animals. In mice between 13 and 60 days of infection, the coexistence of exoantigens and homologous antibodies was also observed. The exoantigens are not strain specific since a cross reactivity between antigens from three strains of T. cruzi (Tulahuén, Higueras, and Alejandro) was seen. Finally, the presence of antibodies to exoantigens in humans with chronic Chagas’ disease was demonstrated. 相似文献
14.
Annarosa Selli Franca Crociani Diego Matteuzzi Giorgio Crisetig 《Current microbiology》1986,13(1):33-38
Feedback inhibition of crude and purified extracts of homoserine dehydrogenase and threonine deaminase activities in the genusBifidobacterium was studied. Homoserine dehydrogenase was partially or completely inhibited byl-threonine, and a marked inhibitory effect byl-isoleucine on threonine deaminase was observed. In the speciesBifidobacterium cuniculi high levels ofl-valine reversed the inhibitory effect ofl-isoleucine. The -aminobutyric acid-resistant mutant Ru 326/106 of the speciesB. ruminale, overproducer ofl-isoleucine, had a derepressed homoserine dehydrogenase and a lesser feedback inhibition byl-threonine. Homoserine dehydrogenase appeared to be in bifids specifically NAD dependent. The regulatory mechanisms of aspartate family amino acid biosynthesis in bifidobacteria was discussed. 相似文献
15.
16.
Gianni Bonadonna Silvio Monfardini Mario de Lena Franca Fossati-Bellani 《BMJ (Clinical research ed.)》1969,3(5669):503-506
Adriamycin, a new antitumour antibiotic of the anthracycline group with a structural formula very similar to daunorubicin, has proved to have potent tumour-growth-inhibiting properties, and to be particularly effective in childhood malignancies. Though adriamycin produces a higher percentage of side-effects than daunorubicin—namely, stomatitis and alopecia—a lower dosage may be used for therapy. 相似文献
17.
18.
Duplication of an Xp segment that includes the ZFX locus causes sex inversion in man 总被引:6,自引:6,他引:0
Gerd Scherer Werner Schempp Carlo Baccichetti Elisabetta Lenzini Franca Dagna Bricarelli Laura Doria Lamba Carbone Ulrich Wolf 《Human genetics》1989,81(3):291-294
Summary Two 46,XY females with tandem duplications of an X short arm segment were studied by cytogenetic and Southern blot analysis. The results show that the duplicated segment in each case included the Xp21.2–Xp22.2 interval, resulting in a double dose of ZFX on the single active X chromosome. The results from our two cases, in conjunction with those reported by other workers, lead us to conclude that the duplication is the reason for the sex inversion. If ZFY and ZFX are indeed sex-determining gene loci, these findings favour a model of sex determination characterized by antagonistic interaction between these genes. 相似文献
19.
G. Benzi A. Gorini B. Ghigini A. Moretti F. Dagani R. F. Villa 《Neurochemical research》1996,21(1):7-18
The changes in the Mg2+-dependent V-type ATPase activity and the Mg2+-ATP-dependent H+ pumping activity of the synaptic vesicles from the cerebral cortex of rats submitted to intermittent chronic (4 weeks) mild
or severe hypoxia were evaluated. The adaptation to the chronic severe hypoxia increases both the ATPase and the H+ pumping activities which are inhibited by NEM with an exponential relationship between the IC50 values and the in vivo O2 concentration. The Mg2+-dependent increase in H+ pumping activity of synaptic vesicles from the rats subjected to in vivo chronic hypoxia may be antagonized by nigericin
(dissipating ΔpH) and by FCCP (dissipating ΔpH and ΔΨSV). In contrast, valinomycin (dissipating the ΔΨSV and facilitating an enhancement in ΔpH) increases in vitro the H+ pumping activity that is inhibited by the addition of high concentration of K gluconate (reducing the rate of K+ efflux). The preincubation of vesicles from hypoxic rats with FCCP, but not with nigericin, inhibits the valinomycin-increased
H+ pumping activity.l-glutamate increases the H+ pumping activity in synaptic vesicles from the cerebral cortex of chronic hypoxic rats, whereas other amino acids (i.e.,l-aspartate andl-homocysteate) and glutamate analogs (i.e., quisqualate and ibotenate) are ineffective. The adaptation to both chronic intermittent
severe hypoxia and in vivo treatment with posatireline causes a decrease in the Mg2+-ATPase activity consistent with the decrease in the H+ pumping one of the synaptic vesicles. The addition of nigericin into incubation medium magnifies the decrease in the H+ pumping activity, while the addition of FCCP is ineffective, suggesting that the treatment with posatireline interferes with
the ΔΨSV component in the
of the synaptic vesicles from rats submitted to chronic hypoxia. The results of the in vivo and in vitro experiments suggest
that in the synaptic vesicles from hypoxic rats the ΔΨSV component in
may be most effective in increasing the Mg2+-ATP-dependent H+ pumping activity. 相似文献
20.
Fusaproliferin production by Fusarium subglutinans and its toxicity to Artemia salina, SF-9 insect cells, and IARC/LCL 171 human B lymphocytes.
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A Logrieco A Moretti F Fornelli V Fogliano A Ritieni M F Caiaffa G Randazzo A Bottalico L Macchia 《Applied microbiology》1996,62(9):3378-3384
Fusarium subglutinans is an important pathogen of maize and other commodities worldwide. We examined MRC-115 and 71 other F. subglutinans strains from various geographic areas for their ability to synthesize fusaproliferin, a novel toxic sesterterpene recently isolated from F. proliferatum. Fusaproliferin production ranged from 30 to 1,500 micrograms/g of dried ground substrate, with 33 strains producing more than 500 micrograms/g. In particular, strain MRC-115 produced as much as 1,100 to 1,300 micrograms/g. In toxicity studies of two invertebrate models, fusaproliferin was toxic to Artemia salina (50% lethal dose, 53.4 microM) and to the lepidopteran cell line SF-9 (50% cytotoxic concentration, approximately 70 microM, after a 48-h exposure). Fusaproliferin was also toxic to the human nonneoplastic B-lymphocyte cell line IARC/LCL 171 (50% cytotoxic concentration, approximately 55 microM in culture in stationary phase after a 48-h exposure). Experiments performed will cells exposed at seeding suggested a possible cytostatic effect at subtoxic concentrations. 相似文献