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11.
12.
Summary This paper presents the preliminary observations on the interstitial fauna of the south-west coast of India, made during the course of 1963–1964. Observations were made at four stations representing different ecological habitats. The influence of some factors, such as wave action, grain size, temperature and salinity on the fauna was studied. The occurrence, seasonal abundance and the nature of distribution of the different groups on the intertidal zone, were also studied at the four stations. 相似文献
13.
Effect of soil solarization on nodulation,infection by mycorrhizal fungi and yield of cowpea 总被引:1,自引:1,他引:0
S. K. Nair C. K. Peethambaran D. Geetha Kamala Nayar K. I. Wilson 《Plant and Soil》1990,125(1):153-154
Solarization of soil was found beneficial for plant growth in cowpea under field conditions. Root nodulation, infection by
mycorrhizal fungi and yield were higher in plants grown in solarized soil. These increases were to the extent of 104.7, 20.0
and 23.7 per cent respectively when compared to control treatment without solarization. 相似文献
14.
Hisao Kurazono Shinji Yamasaki Orn-anong Ratchtrachenchai G. Balakrish Nair Yoshifumi Takeda 《Microbiology and immunology》1996,40(4):303-305
Vibrio cholerae O139 isolated from different countries, as well as from different locations within a country, were examined using macrorestriction DNA analysis to determine the clonality of the O139 strains. NotI digests of genomic DNA of representative strains from Nepal, India, Bangladesh, China, Thailand, and Malaysia revealed very similar but not identical patterns. Examinations of the banding patterns generated by pulsed-field gel electrophoresis of strains isolated within countries revealed complete homogeneity. These results further reiterate the spread of an identical clone of V. cholerae O139 although it appears that genetic polymorphism among the O139 strains is becoming apparent. 相似文献
15.
Two major problems associated with biofouling studies are the lack of broad scale testing and failure to use consistent standards among different assays or studies. To address these issues the activity of two biologically active natural products, elatol and deschloroelatol, isolated from the marine red alga Laurencia rigida, and three commonly used biocides, Nopcocide N-96?, Irgarol 1051? and Sea-Nine 211?, was compared, in a broad spectrum of bioassays. The activity of the different compounds varied substantially among different bioassay tests. Elatol and deschloroelatol had a narrow range of activity with strongest effects against invertebrate larvae. Both compounds were highly toxic. However, neither compound had strong activity against marine bacteria or the common epiphyte Ulva lactuca. Irgarol 1051 also had a narrow range of activity, only affecting algal settlement strongly. Nopcocide N-96 and Sea-Nine 211 had moderate to strong activity across the spectrum of bioassays, viz. growth of marine bacteria (Vibrio fischeri, Serratia sp.), inhibition of settlement of macroalgae (Ulva lactuca), toxicity (Balanus amphitrite), and inhibition of settlement of invertebrate larvae (Balanus amphitrite, Bugula neritina). Based on the results it is proposed that Sea-Nine 211, because of its broad spectrum activity, be used as a standard for comparative assessments of the antifouling activity of marine natural products and analogues. 相似文献
16.
The synthesis of pectinase is investigated using six species of Aspergillus, with five media differing either in their carbon sources or level of carbon source(s). Five of the six species used, synthesized appreciable amounts of pectinase in the media containing sugars. Pectinase synthesis was highest for A. niger, NCIM 548, with all the sugar containing media. A. foetidus, NCIM 510, was the only one among the organisms studied, that responded well to the medium containing pectin in the absence of additional sugars supplied in the medium. 相似文献
17.
Xanthomonas campestris pv. glycines , (Xcg), the causative agent of the bacterial pustule disease of soybean was isolated and characterized. On susceptible soybean the pathogenic isolates displayed characteristic chlorotic lesions around the site of infection within 48 h of inoculation. The pathogenic isolates were found to contain two cryptic plasmids. A smaller plasmid of 1.5 kb and a larger one of size about 25 kb. SDS-PAGE profile of the soluble proteins of the pathogenic isolatess, howed a different pattern compared to that of the non-pathogenic isolates. 相似文献
18.
The anti-inflammatory effect of a small molecular weight antagonist of P- and E-selectin-dependent cell adhesion was examined. The glycolipid sulphatide was shown to block the adherence of thrombin-activated rat platelets to HL-60 cells. This interaction is known to be dependent on P-selectin. The rat dermal reverse passive Arthus reaction was used to assess the effect of sulphatide on a neutrophil dependent inflammatory response. Sulphatide dosedependently blocked both the vascular permeability increase and cell infiltration after intraperitoneal administration. These results show that a small molecular weight compound which blocks P- and E-selectin dependent adhesion in vitro can effectively block the inflammation due to immune complex deposition. A compound with this type of profile may have therapeutic potential in the treatment of immune complex mediated diseases. 相似文献
19.
A. Jayakumaran Nair G. S. Khatri I. M. Santha S. L. Mehta 《Journal of plant biochemistry and biotechnology.》1994,3(2):103-106
A gene responsible for the degradation of ß-N-Oxalyl diaminopropionic acid (ODAP) was fused to the maIE gene, which codes for maltose binding protein, by cloning into an expression vector pMAL c2. The gene has been expressed as fusion protein of mol wt approximately 62 kD. It has been purified by affinity chromatography. The fusion protein has been cleaved by an endoprotease factor Xa and the presence of maltose binding protein and the product of the cloned gene confirmed. SDS-PAGE has shown that the product of the ODAP degrading gene is a single polypeptide of mol wt of about 20.7 kD. 相似文献
20.
Epidemic isolates of Vibrio cholerae 0139 express antigenically distinct types of colonization pili 总被引:2,自引:0,他引:2
T.K. Sengupta D.K. Sengupta G. Balakrish Nair Asoke C. Ghose 《FEMS microbiology letters》1994,118(3):265-271
Abstract Vibrio cholerae belonging to the recently described serogroup 0139, which are responsible for the current cholera epidemics in India and Bangladesh, were shown to express pilus-like structures partially cross-reacting with the toxin-coregulated pilus of V. cholerae strain (0395) belonging to the 01 serogroup and classical biotype. The 0139 pili were composed of 20 kDa subunit proteins which were antigenically related to the 20 kDa pilus protein of another diarrhoeagenic non-01 V. cholerae strain (serogroup 034) isolated earlier. The pili described in this study were found to be involved in the intestinal colonization process and, therefore, may contribute towards the virulence of the 0139 epidemic isolates. 相似文献