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101.
A novel human retrovirus (HTLV-II) was previously found associated with a T-cell variant of hairy-cell leukaemia. Molecular cloning demonstrates that the complete provirus genome is 8.8 kilobase pairs in size and is transmissible to uninfected cells. Two types of infectious deleted provirus were also characterized. The sequences of HTLV-II are distinct from those of HTLV-I. 相似文献
102.
M. G. Clark J. F. Williams G. Kolos J. B. Hickie 《Cellular and molecular life sciences : CMLS》1972,28(5):613-615
Zusammenfassung Methodenvergleich zur Transketolase-Analyse in Rattenherzen. Die neue Methode benützt als Substrat Hydroxypyruvat und Erythrose-4-Phosphat und bestimmt das Verhältnis der Transketolaseaktivität an der Bildung von Fructose-6-Phosphat. Der Wechsel der Myocard-Transketolaseaktivität während Hypertrophie wird beschrieben.
M.G.C. acknowledges the support of an Imperial Chemical Industries of Australia and New Zealand Postgraduate Fellowship. J.F.W. and J.B.H. acknowledge the financial support of the National Heart Foundation of Australia and J.F.W. acknowledges the financial support of the Australian Research Grants Committee. G.K. is a Postgraduate Medical Scholar of the National Heart Foundation of Australia. 相似文献
M.G.C. acknowledges the support of an Imperial Chemical Industries of Australia and New Zealand Postgraduate Fellowship. J.F.W. and J.B.H. acknowledge the financial support of the National Heart Foundation of Australia and J.F.W. acknowledges the financial support of the Australian Research Grants Committee. G.K. is a Postgraduate Medical Scholar of the National Heart Foundation of Australia. 相似文献
103.
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105.
Babesia microti and Plasmodium berghei yoelii infections in nude mice 总被引:23,自引:0,他引:23
106.
Catherine M. Clark Jennifer A. Steele G. A. J. Goodlad 《Cellular and molecular life sciences : CMLS》1971,27(2):216-217
Résumé Chez la rate gravide, la réduction du corticosterone, exprimé par gramme de foie fut augmentée les douzièmes et quatorzième jours de gestation. L'activité du foie entier augmenta à partir du douzième jour. 相似文献
107.
Primary carbonatite melt from deeply subducted oceanic crust 总被引:2,自引:0,他引:2
Walter MJ Bulanova GP Armstrong LS Keshav S Blundy JD Gudfinnsson G Lord OT Lennie AR Clark SM Smith CB Gobbo L 《Nature》2008,454(7204):622-625
Partial melting in the Earth's mantle plays an important part in generating the geochemical and isotopic diversity observed in volcanic rocks at the surface. Identifying the composition of these primary melts in the mantle is crucial for establishing links between mantle geochemical 'reservoirs' and fundamental geodynamic processes. Mineral inclusions in natural diamonds have provided a unique window into such deep mantle processes. Here we provide experimental and geochemical evidence that silicate mineral inclusions in diamonds from Juina, Brazil, crystallized from primary and evolved carbonatite melts in the mantle transition zone and deep upper mantle. The incompatible trace element abundances calculated for a melt coexisting with a calcium-titanium-silicate perovskite inclusion indicate deep melting of carbonated oceanic crust, probably at transition-zone depths. Further to perovskite, calcic-majorite garnet inclusions record crystallization in the deep upper mantle from an evolved melt that closely resembles estimates of primitive carbonatite on the basis of volcanic rocks. Small-degree melts of subducted crust can be viewed as agents of chemical mass-transfer in the upper mantle and transition zone, leaving a chemical imprint of ocean crust that can possibly endure for billions of years. 相似文献
108.
Mustard JF Murchie SL Pelkey SM Ehlmann BL Milliken RE Grant JA Bibring JP Poulet F Bishop J Dobrea EN Roach L Seelos F Arvidson RE Wiseman S Green R Hash C Humm D Malaret E McGovern JA Seelos K Clancy T Clark R Marais DD Izenberg N Knudson A Langevin Y Martin T McGuire P Morris R Robinson M Roush T Smith M Swayze G Taylor H Titus T Wolff M 《Nature》2008,454(7202):305-309
Phyllosilicates, a class of hydrous mineral first definitively identified on Mars by the OMEGA (Observatoire pour la Mineralogie, L'Eau, les Glaces et l'Activitié) instrument, preserve a record of the interaction of water with rocks on Mars. Global mapping showed that phyllosilicates are widespread but are apparently restricted to ancient terrains and a relatively narrow range of mineralogy (Fe/Mg and Al smectite clays). This was interpreted to indicate that phyllosilicate formation occurred during the Noachian (the earliest geological era of Mars), and that the conditions necessary for phyllosilicate formation (moderate to high pH and high water activity) were specific to surface environments during the earliest era of Mars's history. Here we report results from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) of phyllosilicate-rich regions. We expand the diversity of phyllosilicate mineralogy with the identification of kaolinite, chlorite and illite or muscovite, and a new class of hydrated silicate (hydrated silica). We observe diverse Fe/Mg-OH phyllosilicates and find that smectites such as nontronite and saponite are the most common, but chlorites are also present in some locations. Stratigraphic relationships in the Nili Fossae region show olivine-rich materials overlying phyllosilicate-bearing units, indicating the cessation of aqueous alteration before emplacement of the olivine-bearing unit. Hundreds of detections of Fe/Mg phyllosilicate in rims, ejecta and central peaks of craters in the southern highland Noachian cratered terrain indicate excavation of altered crust from depth. We also find phyllosilicate in sedimentary deposits clearly laid by water. These results point to a rich diversity of Noachian environments conducive to habitability. 相似文献
109.
Pain A Böhme U Berry AE Mungall K Finn RD Jackson AP Mourier T Mistry J Pasini EM Aslett MA Balasubrammaniam S Borgwardt K Brooks K Carret C Carver TJ Cherevach I Chillingworth T Clark TG Galinski MR Hall N Harper D Harris D Hauser H Ivens A Janssen CS Keane T Larke N Lapp S Marti M Moule S Meyer IM Ormond D Peters N Sanders M Sanders S Sargeant TJ Simmonds M Smith F Squares R Thurston S Tivey AR Walker D White B Zuiderwijk E Churcher C Quail MA Cowman AF Turner CM Rajandream MA Kocken CH 《Nature》2008,455(7214):799-803
Plasmodium knowlesi is an intracellular malaria parasite whose natural vertebrate host is Macaca fascicularis (the 'kra' monkey); however, it is now increasingly recognized as a significant cause of human malaria, particularly in southeast Asia. Plasmodium knowlesi was the first malaria parasite species in which antigenic variation was demonstrated, and it has a close phylogenetic relationship to Plasmodium vivax, the second most important species of human malaria parasite (reviewed in ref. 4). Despite their relatedness, there are important phenotypic differences between them, such as host blood cell preference, absence of a dormant liver stage or 'hypnozoite' in P. knowlesi, and length of the asexual cycle (reviewed in ref. 4). Here we present an analysis of the P. knowlesi (H strain, Pk1(A+) clone) nuclear genome sequence. This is the first monkey malaria parasite genome to be described, and it provides an opportunity for comparison with the recently completed P. vivax genome and other sequenced Plasmodium genomes. In contrast to other Plasmodium genomes, putative variant antigen families are dispersed throughout the genome and are associated with intrachromosomal telomere repeats. One of these families, the KIRs, contains sequences that collectively match over one-half of the host CD99 extracellular domain, which may represent an unusual form of molecular mimicry. 相似文献
110.
Millennial-scale trends in west Pacific warm pool hydrology since the Last Glacial Maximum 总被引:2,自引:0,他引:2
Models and palaeoclimate data suggest that the tropical Pacific climate system plays a key part in the mechanisms underlying orbital-scale and abrupt climate change. Atmospheric convection over the western tropical Pacific is a major source of heat and moisture to extratropical regions, and may therefore influence the global climate response to a variety of forcing factors. The response of tropical Pacific convection to changes in global climate boundary conditions, abrupt climate changes and radiative forcing remains uncertain, however. Here we present three absolutely dated oxygen isotope records from stalagmites in northern Borneo that reflect changes in west Pacific warm pool hydrology over the past 27,000 years. Our results suggest that convection over the western tropical Pacific weakened 18,000-20,000 years ago, as tropical Pacific and Antarctic temperatures began to rise during the early stages of deglaciation. Convective activity, as inferred from oxygen isotopes, reached a minimum during Heinrich event 1 (ref. 10), when the Atlantic meridional overturning circulation was weak, pointing to feedbacks between the strength of the overturning circulation and tropical Pacific hydrology. There is no evidence of the Younger Dryas event in the stalagmite records, however, suggesting that different mechanisms operated during these two abrupt deglacial climate events. During the Holocene epoch, convective activity appears to track changes in spring and autumn insolation, highlighting the sensitivity of tropical Pacific convection to external radiative forcing. Together, these findings demonstrate that the tropical Pacific hydrological cycle is sensitive to high-latitude climate processes in both hemispheres, as well as to external radiative forcing, and that it may have a central role in abrupt climate change events. 相似文献