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991.
Amber L. Annett Damien S. Carson Xavier Crosta Andrew Clarke Raja S. Ganeshram 《Polar Biology》2010,33(1):13-29
Phytoplankton assemblages from seasonally sea-ice covered Ryder Bay (Adelaide Island, Antarctica) were studied over three
austral summers (2004–2007), to link sea-ice variability and environmental conditions with algal speciation. Typical of near-shore
Antarctic waters, biomass was dominated by large diatoms, although the prymnesiophyte Phaeocystis antarctica was numerically dominant. Although there was considerable interannual variability between main diatom species, high biomass
of certain species or species groups corresponded consistently to certain phases of seasonal progression. We present the first
documentation of an extensive bloom of the late-season diatom Proboscia inermis in February 2006, accounting for over 90% of diatom biomass. At this time, water column stratification and nutrient drawdown
were high relative to other periods of the study, although carbon export was relatively low. Melt water flux in this region
promotes well-stratified surface waters and high chlorophyll levels, but not necessarily concurrent increases in export production
relative to seasons with lower freshwater inputs. 相似文献
992.
993.
994.
The pancreas in the marine lizard fish Saurida tumbil (Bloch) encircles the pyloric region of the gastro-intestinal canal. The islets of Langerhans are ovoidal usually with a central cluster of β cells and the α cells in the periphery. In contrast to the β cells, the α cells have larger nuclei. Saurida tumbil is heavily parasitized by cestodes, nematodes and trematodes which infect the pancreas displacing or replacing much of the tissue. 相似文献
995.
Ryosuke Shirasaki Geoffrey M. Matthews Sara Gandolfi Ricardo de Matos Simoes Dennis L. Buckley Joseline Raja Vora Quinlan L. Sievers Johanna B. Brüggenthies Olga Dashevsky Haley Poarch Huihui Tang Megan A. Bariteau Michal Sheffer Yiguo Hu Sondra L. Downey-Kopyscinski Paul J. Hengeveld Brian J. Glassner Eugen Dhimolea Constantine S. Mitsiades 《Cell reports》2021,34(1):108532
996.
Segmentation of Extrapulmonary Tuberculosis Infection Using Modified Automatic Seeded Region Growing
Iman Avazpour M. Iqbal Saripan Abdul Jalil Nordin Raja Syamsul Azmir Raja Abdullah 《Biological procedures online》2009,11(1):241-252
In the image segmentation process of positron emission tomography combined with computed tomography (PET/CT) imaging, previous
works used information in CT only for segmenting the image without utilizing the information that can be provided by PET.
This paper proposes to utilize the hot spot values in PET to guide the segmentation in CT, in automatic image segmentation
using seeded region growing (SRG) technique. This automatic segmentation routine can be used as part of automatic diagnostic
tools. In addition to the original initial seed selection using hot spot values in PET, this paper also introduces a new SRG
growing criterion, the sliding windows. Fourteen images of patients having extrapulmonary tuberculosis have been examined
using the above-mentioned method. To evaluate the performance of the modified SRG, three fidelity criteria are measured: percentage
of under-segmentation area, percentage of over-segmentation area, and average time consumption. In terms of the under-segmentation
percentage, SRG with average of the region growing criterion shows the least error percentage (51.85%). Meanwhile, SRG with
local averaging and variance yielded the best results (2.67%) for the over-segmentation percentage. In terms of the time complexity,
the modified SRG with local averaging and variance growing criterion shows the best performance with 5.273 s average execution
time. The results indicate that the proposed methods yield fairly good performance in terms of the over- and under-segmentation
area. The results also demonstrated that the hot spot values in PET can be used to guide the automatic segmentation in CT
image. 相似文献
997.
998.
Our study describes basic ecological properties of Steinernema siamkayai Tiruchirappalli strain from India. The effect of temperature on nematode infectivity and development, laboratory host range
and foraging behaviour were determined. The data showed that S. siamkayai is a warm-adapted nematode species with larval mortality observed between 15°C and 37.5°C and nematode reproduction occurring
between 20°C and 35°C. All insect species used in this study were susceptible to S. siamkayai under laboratory conditions. Sixty infective juveniles (IJs) per insect were used and the lepidopterans, Galleria mellonella (100%) and Spodoptera exigua (85%), were the most susceptible species followed by the dipteran, Ceratitis capitata (60%), and lepidopteran, Cydia splendana (55%), and the coleopteran, Tenebrio molitor (45%), whereas the coleopteran, Curculio elephas (25%), was the least susceptible species. S. siamkayai infective juveniles (IJs) stood on their tails and jumped and could also attach to a mobile host at a rate of 27 IJs larvae−1 out of 1000 IJs in 10 min. Larval mortality of G. mellonella by S. siamkayai on different substrates (sand, filter paper, filter paper sprinkled with sand) was 100% on all substrates. Number of IJs
out of 100 IJs that penetrated into a G. mellonella host at different soil depths was the highest at the surface (44 IJs larva−1) and the lowest at 5 cm depth (13 IJs larva−1) with no larval mortality observed at 10 cm depth. In addition, the symbiotic bacterium of S. siamkayai was identified as Xenorhabdus stockiae based on genotypic and phenotypic characterisation. Bacterial growth was observed between 15°C and 41°C. 相似文献
999.
1000.
Gold nanoparticles–conjugated quercetin induces apoptosis via inhibition of EGFR/PI3K/Akt–mediated pathway in breast cancer cell lines (MCF‐7 and MDA‐MB‐231) 下载免费PDF全文
Solaimuthu Balakrishnan Sudip Mukherjee Sourav Das Firdous Ahmad Bhat Paulraj Raja Singh Chitta Ranjan Patra Jagadeesan Arunakaran 《Cell biochemistry and function》2017,35(4):217-231
Epidermal growth factor plays a major role in breast cancer cell proliferation, survival, and metastasis. Quercetin, a bioactive flavonoid, is shown to exhibit anticarcinogenic effects against various cancers including breast cancer. Hence, the present study was designed to evaluate the effects of gold nanoparticles–conjugated quercetin (AuNPs‐Qu‐5) in MCF‐7 and MDA‐MB‐231 breast cancer cell lines. Borohydride reduced AuNPs were synthesized and conjugated with quercetin to yield AuNPs‐Qu‐5. Both were thoroughly characterized by several physicochemical techniques, and their cytotoxic effects were assessed by MTT assay. Apoptotic studies such as DAPI, AO/EtBr dual staining, and annexin V‐FITC staining were performed. AuNPs and AuNPs‐Qu‐5 were spherical with crystalline nature, and the size of particles range from 3.0 to 4.5 nm. AuNPs‐Qu‐5 exhibited lower IC50 value compared to free Qu. There was a considerable increase in apoptotic population with increased nuclear condensation seen upon treatment with AuNPs‐Qu‐5. To delineate the molecular mechanism behind its apoptotic role, we analysed the proteins involved in apoptosis and epidermal growth factor receptor (EGFR)–mediated PI3K/Akt/GSK‐3β signalling by immunoblotting and immunocytochemistry. The pro‐apoptotic proteins (Bax, Caspase‐3) were found to be up regulated and anti‐apoptotic protein (Bcl‐2) was down regulated on treatment with AuNPs‐Qu‐5. Additionally, AuNPs‐Qu‐5 treatment inhibited the EGFR and its downstream signalling molecules PI3K/Akt/mTOR/GSK‐3β. In conclusion, administration of AuNPs‐Qu‐5 in breast cancer cell lines curtails cell proliferation through induction of apoptosis and also suppresses EGFR signalling. AuNPs‐Qu‐5 is more potent than free quercetin in causing cancer cell death, and hence, this could be a potential drug delivery system in breast cancer therapy. 相似文献