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排序方式: 共有151条查询结果,搜索用时 171 毫秒
31.
James R. Fuchs Bulbul Pandit Deepak Bhasin Jonathan P. Etter Nicholas Regan Dalia Abdelhamid Chenglong Li Jiayuh Lin Pui-Kai Li 《Bioorganic & medicinal chemistry letters》2009,19(7):2065-2069
Two series of curcumin analogues, a total of twenty-four compounds, were synthesized and evaluated. The most potent compound, compound 23, showed potent growth inhibitory activities on both prostate and breast cancer lines with IC50 values in sub-micromolar range, fifty times more potent than curcumin. Curcumin analogues might be potential anti-tumor agents for breast and prostate cancers. 相似文献
32.
Kamiri M Stift M Srairi I Costantino G El Moussadik A Hmyene A Bakry F Ollitrault P Froelicher Y 《Plant cell reports》2011,30(8):1415-1425
Artificial tetraploid somatic hybrids have been developed for sterile triploid citrus breeding by sexual hybridization between
diploid and tetraploid somatic hybrids. The genetic structure of diploid gametes produced by tetraploid genotypes depends
on the mode of chromosome association at meiosis. In order to evaluate tetraploid inheritance in a tetraploid interspecific
somatic hybrid between mandarin and lemon, we performed segregation studies using cytogenetic and single sequence repeat molecular
markers. Cytogenetic analysis of meiosis in the somatic hybrid revealed 11% tetravalents and 76% bivalents. Inheritance of
the tetraploid hybrid was analyzed by genotyping the triploid progeny derived from a cross between a diploid pummelo and the
tetraploid somatic hybrid, in order to derive genotypes of the meiospores produced by the tetraploid. A likelihood-based approach
was used to distinguish between disomic, tetrasomic, and intermediate inheritance models and to estimate the double reduction
rate. In agreement with expectations based the cytogenetic data, marker segregation was largely compatible with tetrasomic
and inheritance intermediate between disomic and tetrasomic, with some evidence for preferential pairing of homoeologous chromosomes.
This has important implications for the design of breeding programs that involve tetraploid hybrids, and underscores the need
to consider inheritance models that are intermediate between disomic and tetrasomic. 相似文献
33.
Jan Christian Habel Marc Meyer Abdelhamid El Mousadik Thomas Schmitt 《Organisms Diversity & Evolution》2008,8(2):121-129
Climatic oscillations influence the distribution of species in time. Thermophilic species survived the ice ages in refugia around the Mediterranean. Northern Africa is one of the possibly important refugia. In this study we test the genetic differentiation between northern African and European populations, using the marbled white butterfly species complex, Melanargia galathea/M. lachesis, as a model. We studied 18 allozyme loci in 876 individuals from 23 populations representing a major part of Europe (northern Spain to Romania) and the western part of northern Africa (Atlas Mountains). The African populations resemble the European ones in allelic richness; their genetic diversity is higher than in Europe. Cluster analysis discriminated five European genetic groups: M. lachesis, a western European lineage, and three eastern European lineages. However, the African samples did not form a separate cluster within this phenogram, but clustered randomly within the Balkan/southeastern European groups. The genetic differentiation among the African populations (FST 8.8%) was higher than that within any of the European lineages (FST 2.6–5.5%). The high genetic diversity and the relatively strong differentiation of the four African populations sampled in a comparatively limited area of the Atlas Mountains indicate that the most probable origin of M. galathea is northern Africa, with its sibling species, M. lachesis, evolving in parallel in Iberia. Most probably, M. galathea colonised Europe first during the Eem interglacial, some 130 ky ago. Since M. lachesis must have existed on the Iberian peninsula during that period already, M. galathea should have reached Europe via Italy. The genetic differentiation to distinct groups in Europe most probably evolved during the following Würm glacial period. 相似文献
34.
This article examines whether media portrayals of Islam and Muslims are overwhelmingly negative, whether they have evolved over time, and what factors most consistently affect their tone. We analyse every fourth New York Times headline about Islam or Muslims between 1985 and 2013. We find that headlines have not been predominantly negative. In addition, New York Times headlines about Islam and Muslims have become more positive over the long term, even after the 9/11 attacks. Most counter-intuitively, we find that terrorist attacks have had a systematic positive effect on headline tone. During the first four weeks after each Islamist terrorist attack on an American target, the tone of New York Times headlines became significantly more positive compared to the four weeks prior to the attack. However, over the subsequent few months, coverage reverted back toward the tone that prevailed during the weeks before the event. 相似文献
35.
Faten Mezni Arbia Labidi Mohamed Larbi Khouja Lucy Martine Olivier Berdeaux Abdelhamid Khaldi 《化学与生物多样性》2016,13(5):544-548
Pistacia lentiscus L. seed oil is used in some Mediterranean forest area for culinary and medicinal purposes. In this study, we aim to examine, for the first time, the effect of growing area on sterol content of Pistacia lentiscus seed oil. Fruits were harvested from 13 different sites located in northern and central Tunisia. Gas chromatography‐flame‐ionization detection (GC‐FID) was used to quantify sterols and gas chromatography/mass spectrometry (GC/MS) was used to identify them. The major sterol identified was β‐sitosterol with a value ranging from 854.12 to 1224.09 mg/kg of oil, thus making up more than 54% of the total sterols. The other two main sterols were cycloartenol (11%) and 24‐methylene‐cycloartenol (5%). Statistical results revealed that growing location significantly (P < 0.001) affected phytosterol levels in these oils. 相似文献
36.
Oxygen Reactions: Controlling the Active Sites of Sulfur‐Doped Carbon Nanotube–Graphene Nanolobes for Highly Efficient Oxygen Evolution and Reduction Catalysis (Adv. Energy Mater. 5/2016) 下载免费PDF全文
37.
Elkeilsh Amr Awad Yasser M. Soliman Mona H. Abu-Elsaoud Abdelghafar Abdelhamid Magdi T. El-Metwally Ibrahim M. 《Journal of plant research》2019,132(6):881-901
Journal of Plant Research - Water stress reduces crop production significantly, and climate change has further aggravated the problem mainly in arid and semi-arid regions. This was the first study... 相似文献
38.
Camille Taillé Armelle Guénégou Abdelhamid Almolki Marie Piperaud Bénédicte Leynaert Sandrine Vuillaumier Françoise Neukirch Jorge Boczkowski Michel Aubier Joëlle Benessiano Bruno Crestani 《BMC pulmonary medicine》2007,7(1):1-9
Background
Cardiopulmonary exercise testing (CPET) has become an important modality for the evaluation and management of patients with a diverse array of medical problems. However, interpreting these tests is often difficult and time consuming, requiring significant expertise.Methods
We created a computer software program (XINT) that assists in CPET interpretation. The program uses an integrative approach as recommended in the Official Statement of the American Thoracic Society/American College of Chest Physicians (ATS/ACCP) on Cardiopulmonary Exercise Testing. In this paper we discuss the principles behind the software. We also provide the detailed logic in an accompanying file (Additional File 1). The actual program and the open source code are also available free over the Internet at http://www.xint.org. For convenience, the required download files can also be accessed from this article.Results
To test the clinical usefulness of XINT, we present the computer generated interpretations of the case studies discussed in the ATS/ACCP document in another accompanying file (Additional File 2). We believe the interpretations are consistent with the document's criteria and the interpretations given by the expert panel.Conclusion
Computers have become an integral part of modern life. Peer-reviewed scientific journals are now able to present not just medical concepts and experimental studies, but actual functioning medical interpretive software. This has enormous potential to improve medical diagnoses and patient care. We believe XINT is such a program that will give clinically useful interpretations when used by the medical community at large. 相似文献39.
Heme oxygenase inhibits human airway smooth muscle proliferation via a bilirubin-dependent modulation of ERK1/2 phosphorylation 总被引:2,自引:0,他引:2
Taillé C Almolki A Benhamed M Zedda C Mégret J Berger P Lesèche G Fadel E Yamaguchi T Marthan R Aubier M Boczkowski J 《The Journal of biological chemistry》2003,278(29):27160-27168
The aim of this study was to investigate whether the heme oxygenase (HO) pathway could modulate proliferation of airway smooth muscle (ASM) and the mechanism(s) involved in this phenomenon. In cultured human ASM cells, 10% fetal calf serum or 50 ng/ml platelet-derived growth factor AB induced cell proliferation, extracellular and intracellular reactive oxygen species (ROS) production and ERK1/2 phosphorylation. Pharmacological HO-1 induction (by 10 microm hemin or by 20 microm cobalt-protoporphyrin) and HO inhibition (by 25 microm tin-protoporphyrin or by an antisense oligonucleotide), respectively, reduced and enhanced significantly both cell proliferation and ROS production. Neither the carbon monoxide scavenger myoglobin (5-20 microm) nor the guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one could reverse ASM proliferation induced by tin-protoporphyrin, making a role of the CO-cGMP pathway in HO-modulated proliferation unlikely. By contrast, bilirubin (1 microm) and the antioxidant N-acetyl-cysteine (1 mm) significantly reduced mitogen-induced cell proliferation, ROS production, and ERK1/2 phosphorylation. Furthermore, both bilirubin and N-acetyl-cysteine and the ERK1/2 inhibitor PD98059 significantly reversed the effects of HO inhibition on ASM proliferation. These results could be relevant to ASM alterations observed in asthma because activation of the HO pathway prevented the increase in bronchial smooth muscle area induced by repeated ovalbumin challenge in immunized guinea pigs, whereas inhibition of HO had the opposite effect. In conclusion, this study provides evidence for an antiproliferative effect of the HO pathway in ASM in vitro and in vivo through a bilirubin-mediated redox modulation of phosphorylation of ERK1/2. 相似文献
40.