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151.
Yeasts isolated from olive mill wastewaters from southern Italy: technological characterization and potential use for phenol removal 总被引:1,自引:0,他引:1
Milena Sinigaglia Nilde Di Benedetto Antonio Bevilacqua Maria Rosaria Corbo Angela Capece Patrizia Romano 《Applied microbiology and biotechnology》2010,87(6):2345-2354
Olive mill wastewater (OMW) samples from two traditional varieties (Peranzana and Ogliarola Garganica) of Apulian region (southern
Italy) and produced through continuous and traditional methods were microbiologically and chemically examined; thus, 104 yeasts
were isolated and selected for further analyses. The strains were identified as Candida boidinii, Pichia holstii, Pichia membranifaciens, and Saccharomyces cerevisiae and analyzed to assess their suitability to metabolize phenols. Based on phenol metabolism, 27 strains were selected and
inoculated into OMW aliquots to determine their ability to reduce phenols in vivo; then, five strains (identified with the
codes 682—C. boidinii and 625, 642, 647, and 941—P. holstii) were used as a cocktail in wastewaters for a final validation step. In this last experiment, the effects of the temperature
(10–30°C) and (NH4)2SO4 (0.0–6.0 g l−1) were studied through a central composite design approach, and the results highlighted that the cocktail was able to reduce
phenols by 40% at 10°C with 6.0 g l−1 of (NH4)2SO4 added. 相似文献
152.
Fusarium is a ubiquitous hyalohyphomycete isolated from food, widespread in the environment (plants, soil) and present at all latitudes.
Fusarium oxysporum and Fusarium solani are the most frequent pathogenic species, followed by F. moniliforme and F. chlamydosporum. Infections due to this mold may be disseminated or localized. Localized forms include cutaneous and subcutaneous infection,
onychomycosis, endophtalmitis, otitis, sinusitis, arthritis, osteomyelitis, and brain abscess. Disseminated forms are those
in which two or more noncontiguous sites may be involved. These latter are observed in patients with severe neutropenia. Wounds,
digital ulcers, onychomycosis, and paronychia are the typical cutaneous portal of entry. We report a case of primary localized
cutaneous infection due to Fusarium in a 29-year-old woman presenting with a nodular lesion, partially ulcerated, asymptomatic on the first finger of the left
hand, appeared 4 months earlier. Histological examination showed spongiosis and acanthosis in the stratum corneum, ulceration
and inflammation with prevalently mononucleate cells and septate and branched fungal structures in the epidermis and in dermis.
The fungus was identified as Fusarium oxysporum by culture of biopsy fragments on Sabouraud dextrose agar with chloramphenicol. The culture was deposited in the culture
collection of the mycology section of IHEM, Brussels (IHEM21984 col no. 125). The patient had normal immune status and was
successfully treated with surgical excision. Recovery was confirmed at follow-up 8 months later. 相似文献
153.
Pantaleoni RA Baratti M Barraco L Contini C Cossu CS Filippelli MT Loru L Romano M 《Parasite (Paris, France)》2010,17(4):349-355
Recently, in the province of Trapani (Western Sicily), some overwintering specimens of the argasid tick Argos (Persicargas) persicus (Oken, 1818) were observed and collected. Morphological and genetic analysis were utilized in order to reach a definitive identification. The species was found in two semi-natural sites where, having been found repeatedly, its presence does not appear accidental. Moreover the characteristics of the Sicilian findings seem to exclude a human-induced spread. This record, the first regarding Sicily and South Italy, is discussed together with the previous doubtful citations for Italy. These findings revalue not only all the old citations for Italy but also the hypothesis that the Mediterranean distribution of this argasid is of a natural origin. 相似文献
154.
Laura Vannini Silvia Ciolfi Giacomo Spinsanti Cristina Panti Francesco Frati Romano Dallai 《Archives of insect biochemistry and physiology》2010,73(2):106-117
Farnesoic acid O‐methyl transferase (FAMeT) is the enzyme involved in the penultimate step of insect juvenile hormone (JH) biosynthesis and is thus a key regulator in insect development and reproduction. We report the characterization of the putative‐FAMeT in the medfly or Mediterranean fruit fly, Ceratitis capitata. This gene was identified by suppressive subtractive hybridization and completely sequenced by the screening of a medfly cDNA library. The obtained sequence was analyzed for conserved protein domain identification and its expression profile was evaluated by quantitative Real‐Time PCR in medfly pre‐imaginal life. The tissue expression of the isolated gene was verified by in situ hybridization on third instar larvae sections. The characterization of the isolated gene pointed out several typical features of methyl transferase genes. The pre‐imaginal putative‐FAMeT expression levels were consistent with JH titer change in Diptera. As recognized in some crustaceans, this gene seems to be widely expressed in the medfly as well. Ceratitis capitata is one of the most relevant agricultural pests against which insecticides and the sterile insect technique (SIT) are extensively used in spite of the well‐known limitations of these approaches. Although results are not conclusive for the physiological role of the isolated gene, they suggest the characterization of a new gene in the Mediterranean fruit fly potentially involved in JH biosynthesis and may, therefore, have implications for pest control. © 2010 Wiley Periodicals, Inc. 相似文献
155.
Micheli F Antolini M Di Fabio R Pellacani A Pozzan A 《Bioorganic & medicinal chemistry letters》2010,20(22):6405-6407
A new class of selective orexin 2 antagonist was identified among commercial products. Initial SAR was obtained using commercial derivatives only prior to starting ad hoc medicinal chemistry activities. 相似文献
156.
Edson Romano Nucci Antonio J. G. Cruz Roberto C. Giordano 《Bioprocess and biosystems engineering》2010,33(5):557-564
The complexity of biological processes often makes impractical the development of detailed, structured phenomenological models
of the cultivation of microorganisms in bioreactors. In this context, data pre-treatment techniques are useful for bioprocess
control and fault detection. Among them, principal component analysis (PCA) plays an important role. This work presents a
case study of the application of this technique during real experiments, where the enzyme penicillin G acylase (PGA) was produced
by Bacillus megaterium ATCC 14945. PGA hydrolyzes penicillin G to yield 6-aminopenicilanic acid (6-APA) and phenyl acetic acid. 6-APA is used to
produce semi-synthetic β-lactam antibiotics. A static PCA algorithm was implemented for on-line detection of deviations from
the desired process behavior. The experiments were carried out in a 2-L bioreactor. Hotteling’s T
2 was the discrimination criterion employed in this multivariable problem and the method showed a high sensibility for fault
detection in all real cases that were studied. 相似文献
157.
158.
Nicholas Romano Chaoshu Zeng 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2010,151(2):222-228
Ammonia-N toxicity to early Portunus pelagicus juveniles at different salinities was investigated along with changes to haemolymph osmolality, Na+, K+, Ca2+ and ammonia-N levels, ammonia-N excretion and gill Na+/K+-ATPase activity. Experimental crabs were acclimated to salinities 15, 30 and 45‰ for one week and 25 replicate crabs were subsequently exposed to 0, 20, 40, 60, 80, 100 and 120 mg L− 1 ammonia-N for 96-h, respectively. High ammonia-N concentrations were used to determine LC50 values while physiological measurements were conducted at lower concentrations. When crabs were exposed to ammonia-N, anterior gill Na+/K+-ATPase activity significantly increased (p < 0.05) at all salinities, while this only occurred on the posterior gills at 30‰. For crabs exposed to 20 and 40 mg L− 1 ammonia-N, both posterior gill Na+/K+-ATPase activity and ammonia-N excretion were significantly higher at 15‰ than those at 45‰. Despite this trend, the 96-h LC50 value at 15‰ (43.4 mg L− 1) was significantly lower (p < 0.05) than at both 30‰ and 45‰ (65.8 and 75.2 mg L− 1, respectively). This may be due to significantly higher (p < 0.05) haemolymph ammonia-N levels of crabs at low salinities and may similarly explain the general ammonia-N toxicity pattern to other crustacean species. 相似文献
159.
R-cells are mouse embryo fibroblasts with a targeted disruption of the insulin-like growth factor I receptor (IGF-IR) genes. Because R-cells do not express the IGF-IR, they are ideal for studying the biological effects of the insulin receptor (IR), independently from any contribution by the IGF-IR. By stably transfecting R-cells with constructs expressing the IR, we show here the IR can protect cells from apoptosis induced by anoikis or by okadaic acid. The IR, however, is not as efficient as the IGF-IR in protecting mouse embryo fibroblasts from apoptosis, even when IRS-1, one of its major substrates, is over-expressed. In addition, the protection by the IGF-IR is resistant to inhibitors of phosphatidylinositol 3-kinase (PI 3-ki), while the anti-apoptotic effect of the IR is sensitive. These experiments suggest that the IGF-IR uses an alternative anti-apoptotic pathway, not shared with the IR, which is PI3-ki-independent. 相似文献
160.