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101.
We report on the use of infrared‐triggered cameras as an effective tool to survey phasianid populations in Wanglang and Wolong Nature Reserves, China. Surveys at 183 camera‐trapping sites recorded 30 bird species, including nine phasianids (one grouse and eight pheasant species). Blood Pheasant Ithaginis cruentus and Temminck’s Tragopan Tragopan temminckii were the phasianids most often detected at both reserves and were found within the mid‐elevation range (2400–3600 m asl). The occupancy rate and detection probability of both species were examined using an occupancy model relative to eight sampling covariates and three detection covariates. The model estimates of occupancy for Blood Pheasant (0.30) and Temminck’s Tragopan (0.14) are close to the naïve estimates based on camera detections (0.27 and 0.13, respectively). The estimated detection probability during a 5‐day period was 0.36 for Blood Pheasant and 0.30 for Temminck’s Tragopan. The daily activity patterns for these two species were assessed from the time/date stamps on the photographs and sex ratios calculated for Blood Pheasant (152M : 72F) and Temminck’s Tragopan (48M : 21F). Infrared cameras are valuable for surveying these reclusive species and our protocol is applicable to research or monitoring of phasianids. 相似文献
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Juha Heijari Minna Kivimäenpää Helinä Hartikainen Riitta Julkunen-Tiitto Anu Wulff 《Plant and Soil》2006,282(1-2):27-39
In greenhouse experiments, selenium (Se) has been shown to defend plants against detrimental effects of heavy UV-B radiation
stress. The aim of this study was to investigate whether this positive effect can be found in open-field conditions with enhancement
of UV-B radiation. In the experiment, conducted with strawberry (Fragaria×ananassa, cultivars “Jonsok” and “Polka”) over two growing seasons, plants were exposed to UV-B radiation (including UV-A) and cultivated
without Se or supplied with Se added at two levels (0.1 and 1.0 mg kg−1). The plants were monitored for growth, flavonoids, chlorophyll fluorescence, net photosynthesis as well as tissue and cell
structure. Photosystem II was observed to be sensitive to UV-B stress under field conditions. In the leaves, a decrease in
Fv/Fm was seen at the end of the growing season, implying a cumulative effect of UV-B stress. Several parameters, especially cell
and tissue structures, were affected by UV-B and UV-A treatments, which proves the need for UV-A control in outdoor UV-B supplementation
studies. Addition of Se did not ameliorate the harmful effects of UV-B but the lower Se-increment level increased leaf growth.
The effects of UV-B and Se differed during the two experimental years, indicating the need to repeat experiments during several
growing seasons. 相似文献
104.
The bHLH transcription factor MdbHLH3 promotes anthocyanin accumulation and fruit colouration in response to low temperature in apples 总被引:1,自引:0,他引:1
105.
Kandiba L Aitio O Helin J Guan Z Permi P Bamford DH Eichler J Roine E 《Molecular microbiology》2012,84(3):578-593
VP4, the major structural protein of the haloarchaeal pleomorphic virus, HRPV‐1, is glycosylated. To define the glycan structure attached to this protein, oligosaccharides released by β‐elimination were analysed by mass spectrometry and nuclear magnetic resonance spectroscopy. Such analyses showed that the major VP4‐derived glycan is a pentasaccharide comprising glucose, glucuronic acid, mannose, sulphated glucuronic acid and a terminal 5‐N‐formyl‐legionaminic acid residue. This is the first observation of legionaminic acid, a sialic acid‐like sugar, in an archaeal‐derived glycan structure. The importance of this residue for viral infection was demonstrated upon incubation with N‐acetylneuraminic acid, a similar monosaccharide. Such treatment reduced progeny virus production by half 4 h post infection. LC‐ESI/MS analysis confirmed the presence of pentasaccharide precursors on two different VP4‐derived peptides bearing the N‐glycosylation signal, NTT. The same sites modified by the native host, Halorubrum sp. strain PV6, were also recognized by the Haloferax volcanii N‐glycosylation apparatus, as determined by LC‐ESI/MS of heterologously expressed VP4. Here, however, the N‐linked pentasaccharide was the same as shown to decorate the S‐layer glycoprotein in this species. Hence, N‐glycosylation of the haloarchaeal viral protein, VP4, is host‐specific. These results thus present additional examples of archaeal N‐glycosylation diversity and show the ability of Archaea to modify heterologously expressed proteins. 相似文献
106.
CD36 is recognized as a lipid and fatty acid receptor and plays an important role in the metabolic syndrome and associated cardiac events. The pleiotropic activity and the multiple molecular associations of this scavenger receptor with membrane associated molecules in different cells and tissues have however questioned its potential as a therapeutic target. The present study shows that it is possible to identify low molecular weight chemicals that can block the CD36 binding and uptake functions. These inhibitors were able to reduce arterial lipid deposition, fatty acid intestinal transit, plasma concentration of triglycerides and glucose, to improve insulin sensitivity, glucose tolerance and to reduce the plasma concentration of HbAc1 in different and independent rodent models. Correlation between the anti-CD36 activity of these inhibitors and the known pathophysiological activity of this scavenger receptor in the development of atherosclerosis and diabetes were observed at pharmacological doses. Thus, CD36 might represent an attractive therapeutic target. 相似文献
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109.
In this study, we aimed to investigate the distribution pattern of ubiquitin and p97/VCP in the rat retina during postnatal
development. Eyeballs from 1-, 4-, 10-, 36- and 72-week-old rats were examined by immunohistochemistry, and protein colocalization
was determined by immunofluorescence microscopy. In the 1-week-old rat retina, p97/VCP was strongly expressed in the neuroblast
layer, however no ubiquitin immunoreactivity was observed. p97/VCP immunoreactivity was present in the ganglion cell layer
(GCL), inner nuclear layer (INL), outer nuclear layer (ONL), inner segment (IS) of the photoreceptor layer, and retinal pigment
epithelium in the 4- and 10-week-old rat retinas. p97/VCP immunoreactivity increased significantly in the 10-week-old rat
retinas. Ubiquitin was barely seen in the 4-week-old rat retinas, and ubiquitin expression was weak in the GCL and the IPL
of the 10-week-old rat retinas. In the 36- and 72-week-old rats, the presence of ubiquitin was remarkable in the IS, INL,
IPL and GCL, however, p97/VCP immunoreactivity was significantly decreased. Colocalization of ubiquitin and p97/VCP was also
observed in the INL, IS, GCL and ONL of 36- and 72-week-old rat retinas. Our results indicate that p97/VCP immunoreactivity
in the retina significantly decreases after rats reach 10 weeks of age, whereas ubiquitin immunoreactivity increases with
aging. These results suggest that an altered expression pattern of p97/VCP and ubiquitin in the developing rat retina may
associate with age-related retinal degeneration. 相似文献
110.
报道在江西和河南发现的浮姬蜂属Phobetes F(o)rster,1869的种类,其中有2新种:白环浮姬蜂Ph.albiannularis sp.nov.和河南浮姬蜂Ph.henanensis sp.nov.;中国1新纪录种:北海道浮姬蜂Ph.sapporensis( Uchida,1930).指出了新种与近似种的鉴别特征,并附彩色特征图.编制了该属中国已知种的检索表. 相似文献