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31.
MOTIVATION: High-throughput 'ChIP-chip' and 'ChIP-seq' methodologies generate sufficiently large data sets that analysis poses significant informatics challenges, particularly for research groups with modest computational support. To address this challenge, we devised a software platform for storing, analyzing and visualizing high resolution genome-wide binding data. GeneTrack automates several steps of a typical data processing pipeline, including smoothing and peak detection, and facilitates dissemination of the results via the web. Our software is freely available via the Google Project Hosting environment at http://genetrack.googlecode.com 相似文献
32.
Philippa A. West Natacha Protopopoff Alexandra Wright Zuhura Kivaju Robinson Tigererwa Franklin W. Mosha William Kisinza Mark Rowland Immo Kleinschmidt 《PLoS medicine》2014,11(4)
Background
Insecticide-treated nets (ITNs) and indoor residual spraying (IRS) of houses provide effective malaria transmission control. There is conflicting evidence about whether it is more beneficial to provide both interventions in combination. A cluster randomised controlled trial was conducted to investigate whether the combination provides added protection compared to ITNs alone.Methods and Findings
In northwest Tanzania, 50 clusters (village areas) were randomly allocated to ITNs only or ITNs and IRS. Dwellings in the ITN+IRS arm were sprayed with two rounds of bendiocarb in 2012. Plasmodium falciparum prevalence rate (PfPR) in children 0.5–14 y old (primary outcome) and anaemia in children <5 y old (secondary outcome) were compared between study arms using three cross-sectional household surveys in 2012. Entomological inoculation rate (secondary outcome) was compared between study arms.IRS coverage was approximately 90%. ITN use ranged from 36% to 50%. In intention-to-treat analysis, mean PfPR was 13% in the ITN+IRS arm and 26% in the ITN only arm, odds ratio = 0.43 (95% CI 0.19–0.97, n = 13,146). The strongest effect was observed in the peak transmission season, 6 mo after the first IRS. Subgroup analysis showed that ITN users were additionally protected if their houses were sprayed. Mean monthly entomological inoculation rate was non-significantly lower in the ITN+IRS arm than in the ITN only arm, rate ratio = 0.17 (95% CI 0.03–1.08).Conclusions
This is the first randomised trial to our knowledge that reports significant added protection from combining IRS and ITNs compared to ITNs alone. The effect is likely to be attributable to IRS providing added protection to ITN users as well as compensating for inadequate ITN use. Policy makers should consider deploying IRS in combination with ITNs to control transmission if local ITN strategies on their own are insufficiently effective. Given the uncertain generalisability of these findings, it would be prudent for malaria control programmes to evaluate the cost-effectiveness of deploying the combination.Trial registration
www.ClinicalTrials.gov Please see later in the article for the Editors'' Summary NCT01697852相似文献33.
Ritha JA Njau Don de Savigny Lucy Gilson Eleuther Mwageni Franklin W Mosha 《Malaria journal》2009,8(1):1-27
Background
In the past decade there has been increasing visibility of malaria control efforts at the national and international levels. The factors that have enhanced this scenario are the availability of proven interventions such as artemisinin-based combination therapy, the wide scale use of insecticide-treated nets (ITNs) and a renewed emphasis in indoor residual house-spraying. Concurrently, there has been a window of opportunity of financial commitments from organizations such as the Global Fund for HIV/AIDS, Tuberculosis and Malaria (GFATM), the President's Malaria Initiative and the World Bank Booster programme.Methods
The case study uses the health policy analysis framework to analyse the implementation of a public-private partnership approach embarked upon by the government of Tanzania in malaria control – 'The Tanzania National Voucher Scheme'- and in this synthesis, emphasis is on the challenges faced by the scheme during the pre-implementation (2001 – 2004) and implementation phases (2004 – 2005). Qualitative research tools used include: document review, interview with key informants, stakeholder's analysis, force-field analysis, time line of events, policy characteristic analysis and focus group discussions. The study is also complemented by a cross-sectional survey, which was conducted at the Rufiji Health Demographic Surveillance Site, where a cohort of women of child-bearing age were followed up regarding access and use of ITNs.Results
The major challenges observed include: the re-introduction of taxes on mosquito nets and related products, procurement and tendering procedures in the implementation of the GFATM, and organizational arrangements and free delivery of mosquito nets through a Presidential initiative.Conclusion
The lessons gleaned from this synthesis include: (a) the consistency of the stakeholders with a common vision, was an important strength in overcoming obstacles, (b) senior politicians often steered the policy agenda when the policy in question was a 'crisis event', the stakes and the visibility were high, (c) national stakeholders in policy making have an advantage in strengthening alliances with international organizations, where the latter can become extremely influential in solving bottlenecks as the need arises, and (d) conflict can be turned into an opportunity, for example the Presidential initiative has inadvertently provided Tanzania with important lessons in the organization of 'catch-up' campaigns. 相似文献34.
35.
Linam Franklin Limmer Matt A. Tappero Ryan Seyfferth Angelia L. 《Plant and Soil》2022,477(1-2):135-152
Plant and Soil - Rice is a staple crop worldwide and a silicon (Si) hyperaccumulator with Si levels reaching 5–10% of its mass; this can result in desilication and Si-deficiency if plant... 相似文献
36.
Higgins JD Buckling EF Franklin FC Jones GH 《The Plant journal : for cell and molecular biology》2008,54(1):152-162
Meiotic crossovers/chiasmata, that are required to ensure chromosome disjunction, arise via the class I interference-dependent pathway or via the class II interference-free pathway. The proportions of these two classes vary considerably between different organisms. In Arabidopsis, about 85% of chiasmata are eliminated in Atmsh4 mutants, denoting that these are class I events. In budding and fission yeasts Msh4-independent crossovers arise largely or entirely via a Mus81-dependent pathway. To investigate the origins of the 15% residual (AtMSH4-independent) chiasmata in Arabidopsis we conducted a cytological and molecular analysis of AtMUS81 meiotic expression and function. Although AtMUS81 functions in somatic DNA repair and recombination, it is more highly expressed in reproductive tissues. The protein is abundantly present in early prophase I meiocytes, where it co-localizes, in a double-strand break-dependent manner, with the recombination protein AtRAD51. Despite this, an Atmus81 mutant shows normal growth and has no obvious defects in reproductive development that would indicate meiotic impairment. A cytological analysis confirmed that meiosis was apparently normal in this mutant and its mean chiasma frequency was similar to that of wild-type plants. However, an Atmsh4 / Atmus81 double mutant revealed a significantly reduced mean chiasma frequency (0.85 per cell), compared with an Atmsh4 single mutant (1.25 per cell), from which we conclude that AtMUS81 accounts for some, but not all, of the 15% AtMSH4-independent residual crossovers. It is possible that other genes are responsible for these residual chiasmata. Alternatively the AtMUS81 pathway coexists with an alternative parallel pathway that can perform the same functions. 相似文献
37.
M.J. Dring A. Wagner L.A. Franklin R. Kuhlenkamp K. Lüning 《Helgoland Marine Research》2001,55(1):3-11
Ultraviolet (UV) radiation at four wavelengths (305, 320, 340 and 380 nm) and photosynthetically active radiation (PAR) were
measured from May 1994 to October 1999 using Biospherical UV radiometers. A surface reference sensor located on the roof of
the Marine Station at Helgoland recorded values every 5 min, and an equivalent profiling underwater sensor was used for measurements
in the sea at approximately monthly intervals. The ratio of 305-nm radiation to PAR varied seasonally, with a 14-fold increase
from winter to summer. A much weaker seasonal trend (ca. 1.5-fold) was apparent in the ratio of 320-nm radiation to PAR, but
there was no seasonal trend in the ratios of 340- or 380-nm radiation to PAR. The year-to-year variations in 305-nm radiation
were also much greater relative to PAR than for the other UV wavelengths, but there was no evidence of a change in the 305 nm:PAR
ratio over the study period. The ratios of both 305- and 320-nm radiation to PAR increased from dawn to midday, but those
of 340- and 380-nm radiation were almost constant through the day, except shortly before sunrise and after sunset when the
proportions of 340- and 380-nm radiation increased. Underwater measurements of PAR and UV suggest that the 1% depth for 305-nm
radiation was little more than 1 m, but this estimate is valid only for summer and autumn because, in other seasons, few reliable
readings for 305-nm radiation could be obtained underwater, and no attenuation coefficient could be calculated. The 1% depths
recorded for the other UV wavelengths in the middle 6 months of the year were 2.0 m for 320 nm, 2.6 m for 340 nm and 4.6 m
for 380 nm, compared with 12 m for PAR, but the attenuation of all wavebands increased sharply in October and remained higher
until March. An analysis of the influence of sun angle, total column ozone concentration, the proportion of skylight, and
cloud cover on the ratio of UV wavelengths to PAR in surface irradiance demonstrated that solar angle has a greater influence
than ozone concentration on the irradiance at 305 nm, and that the typical occurrence of ozone "holes" in spring may not result
in higher UV-B irradiances than occur under higher ozone concentrations in summer. The implications of the data for attempts
to model the biological effects of natural UV radiation on marine organisms are considered.
Received in revised form: 3 July 2000
Electronic Publication 相似文献
38.
39.
Osman A. Gutiérrez Arin F. Robinson Johnie N. Jenkins Jack C. McCarty Martin J. Wubben Franklin E. Callahan Robert L. Nichols 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(2):271-280
The identification of molecular markers that are closely linked to gene(s) in Gossypium barbadense L. accession GB713 that confer a high level of resistance to reniform nematode (RN), Rotylenchulus reniformis Linford & Oliveira, would be very useful in cotton breeding programs. Our objectives were to determine the inheritance of
RN resistance in the accession GB713, to identify SSR markers linked with RN resistance QTLs, and to map these linked markers
to specific chromosomes. We grew and scored plants for RN reproduction in the P1, P2, F1, F2, BC1P1, and BC1P2 generations from the cross of GB713 × Acala Nem-X. The generation means analysis using the six generations indicated that
one or more genes were involved in the RN resistance of GB713. The interspecific F2 population of 300 plants was genotyped with SSR molecular markers that covered most of the chromosomes of Upland cotton (G. hirsutum L.). Results showed two QTLs on chromosome 21 and one QTL on chromosome 18. One QTL on chromosome 21 was at map position
168.6 (LOD 28.0) flanked by SSR markers, BNL 1551_162 and GH 132_199 at positions 154.2 and 177.3, respectively. A second
QTL on chromosome 21 was at map position 182.7 (LOD 24.6) flanked by SSR markers BNL 4011_155 and BNL 3279_106 at positions
180.6 and 184.5, respectively. Our chromosome 21 map had 61 SSR markers covering 219 cM. One QTL with smaller genetic effects
was localized to chromosome 18 at map position 39.6 (LOD 4.0) and flanked by SSR markers BNL 1721_178 and BNL 569_131 at positions
27.6 and 42.9, respectively. The two QTLs on chromosome 21 had significant additive and dominance effects, which were about
equal for each QTL. The QTL on chromosome 18 showed larger additive than dominance effects. Following the precedent set by
the naming of the G. longicalyx Hutchinson & Lee and G. aridum [(Rose & Standley) Skovsted] sources of resistance, we suggest the usage of Ren
barb1
and Ren
barb2
to designate these QTLs on chromosome 21 and Ren
barb3
on chromosome 18. 相似文献
40.
Effects of clothianidin on Bombus impatiens (Hymenoptera: Apidae) colony health and foraging ability
We conducted laboratory experiments to investigate the lethal and sublethal effects of clothianidin on bumble bee, Bombus impatiens Cresson, colony health and foraging ability. Bumble bee colonies were exposed to 6 ppb clothianidin, representing the highest residue levels found in field studies on pollen, and a higher dose of 36 ppb clothianidin in pollen. Clothianidin did not effect pollen consumption, newly emerged worker weights, amount of brood or the number of workers, males, and queens at either dose. The foraging ability of worker bees tested on an artificial array of complex flowers also did not differ among treatments. These results suggest that clothianidin residues found in seed-treated canola and possibly other crops will not adversely affect the health of bumble bee colonies or the foraging ability of workers. 相似文献