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131.
Cerebrospinal fluid biomarkers as a measure of disease activity and treatment efficacy in relapsing‐remitting multiple sclerosis 下载免费PDF全文
132.
133.
Dirk Raiser Stephanie Mildner Benedikt Ifland Mohsen Sotoudeh Peter Blöchl Simone Techert Christian Jooss 《Liver Transplantation》2017,7(12)
Understanding and controlling the relaxation process of optically excited charge carriers in solids with strong correlations is of great interest in the quest for new strategies to exploit solar energy. Usually, optically excited electrons in a solid thermalize rapidly on a femtosecond to picosecond timescale due to interactions with other electrons and phonons. New mechanisms to slow down thermalization will thus be of great significance for efficient light energy conversion, e.g., in photovoltaic devices. Ultrafast optical pump–probe experiments in the manganite Pr0.65Ca0.35MnO3, a photovoltaic, thermoelectric, and electrocatalytic material with strong polaronic correlations, reveal an ultraslow recombination dynamics on a nanosecond‐time scale. The nature of long living excitations is further elucidated by photovoltaic measurements, showing the presence of photodiffusion of excited electron–hole polaron pairs. Theoretical considerations suggest that the excited charge carriers are trapped in a hot polaron state. Escape from this state is possible via a slow dipole‐forbidden recombination process or via rare thermal fluctuations toward a conical intersection followed by a radiation‐less decay. The strong correlation between the excited polaron and the octahedral dynamics of its environment appears to be substantial for stabilizing the hot polaron. 相似文献
134.
Nourbakhsh Fatemeh Mohsennia Mohsen Pazouki Mohammad 《Bioprocess and biosystems engineering》2017,40(11):1669-1677
Bioprocess and Biosystems Engineering - A novel nickel oxide/carbon nanotube/polyaniline (NCP) nanocomposite has been prepared and used to modify the electrocatalytic properties of carbon cloth... 相似文献
135.
Ammari M Jeljeli M Jeljeli M Maaroufi K Roy V Sakly M Abdelmelek H 《Electromagnetic biology and medicine》2008,27(2):185-196
The present work investigated the behavioral effects of a moderate exposure (1 h per day for 5 consecutive days) to a static magnetic field (SMF, 128 mT) in male rats. SMF effects were evaluated in two sets of control and SMF-exposed rats. One set of animals was used for evaluation of SMF potential effects on emotional behaviors in the elevated plus maze and in the open field. The other set of animals was tested for learning and memory abilities in different procedures of the Morris water maze task. We found no significant difference between control and SMF-exposed rats in anxiety tests. However, the ratio of open arms time in the plus maze was reduced by half in SMF-exposed rats. In the Morris water maze, SMF-exposed rats were partially impaired during the initial learning task as well as in the retention task at one week. We conclude that static magnetic field exposure altered emotional behaviors in the plus maze and led to cognitive impairments, or at least to substantial attention disorders, in the Morris water maze. 相似文献
136.
V A McCormack I dos Santos Silva B L De Stavola R Mohsen D A Leon H O Lithell 《BMJ (Clinical research ed.)》2003,326(7383):248
ObjectiveTo investigate whether size at birth and rate of fetal growth influence the risk of breast cancer in adulthood.DesignCohort identified from detailed birth records, with 97% follow up.SettingUppsala Academic Hospital, Sweden.Participants5358 singleton females born during 1915-29, alive and traced to the 1960 census.ResultsSize at birth was positively associated with rates of breast cancer in premenopausal women. In women who weighed ⩾4000 g at birth rates of breast cancer were 3.5 times (95% confidence interval 1.3 to 9.3) those in women of similar gestational age who weighed <3000 g at birth. Rates in women in the top fifths of the distributions of birth length and head circumference were 3.4 (1.5 to 7.9) and 4.0 (1.6 to 10.0) times those in the lowest fifths (adjusted for gestational age). The effect of birth weight disappeared after adjustment for birth length or head circumference, whereas the effects of birth length and head circumference remained significant after adjustment for birth weight. For a given size at birth, gestational age was inversely associated with risk (P=0.03 for linear trend). Adjustment for markers of adult risk factors did not affect these findings. Birth size was not associated with rates of breast cancer in postmenopausal women.ConclusionsSize at birth, particularly length and head circumference, is associated with risk of breast cancer in women aged <50 years. Fetal growth rate, as measured by birth size adjusted for gestational age, rather than size at birth may be the aetiologically relevant factor in premenopausal breast cancer.
What is already known on this topic
There is some evidence that birth weight is related to risk of breast cancerThe exact nature of any association and whether it differs at premenopausal and postmenopausal ages is unclearFew studies have examined the effect of other measures of birth size and of gestational ageWhat this study adds
There are strong positive associations between measures of birth size and rates of breast cancer at premenopausal ages that persisted after adjustment for adult risk factorsFor a given birth size, gestational age was inversely associated with risk, suggesting that the rate of fetal growth may be aetiologically relevant to premenopausal breast cancerThere was no association between birth characteristics and rates of breast cancer at postmenopausal ages 相似文献137.
Mohsen Mohamed Selim Asker Youssri Mohamed Ahmed Mohamed Fawzy Ramadan 《Carbohydrate polymers》2009,77(3):563-567
The Gram-positive bacterial strain isolated from soil was identified as the non-pathogenic Microbacterium terregens. The exopolysaccharide (CPS) produced from M. terregens was obtained by isopropanol precipitation (13.72 g L?1 growth medium), The resulted exopolysaccharide was purified by chromatography on DEAE-cellulose and Sephacryl S-200 columns, when two polysaccharide fractions termed CPSI and CPSII were obtained. Structure features of CPSI and CPSII were investigated by a combination of chemical and chromatographic analyses, such as acid hydrolysis, methylation analysis, periodate oxidation–Smith degradation, HPLC, GC–MS, and IR. The results indicated that CPSI and CPSII were composed of glucose: mannose in a ratio of 2.7:1 and 3.2:1 with molecular weights 80 and 150 kDa, respectively. It has a backbone of (1 → 4)-linked β-glucose residues, which occasionally branches at O-6. The branches were composed of (1 → 4)-linked β-mannose residues. The antioxidant activity of the CPS, CPSI and CPSII was evaluated in-vitro by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay (RSA). CPSI fraction showed the highest antioxidant activity among the three fractions, with an IC50 value of 230 μg mL?1. The effect of molecular weight of the polysaccharide on the improvement of the antioxidant potential seems to be significant. 相似文献
138.
Parvin Salehi Shanjani Mohsen Mardi Leila Pazouki Marianna Hagidimitriou Damiano Avanzato S. Mostafa Pirseyedi Mohammad Reza Ghaffari S. Mojtaba Khayam Nekoui 《Tree Genetics & Genomes》2009,5(3):447-458
Knowledge of pistachio genetic diversity is necessary for the formulation of appropriate management strategies for the conservation
of these species. We analysed amplified fragment length polymorphisms in a total of 216 pistachio accessions, which included
seven populations from three wild species (Pistacia vera, Pistacia khinjuk and Pistacia atlantica subsp. kurdica) and most of the important cultivars from Iran, together with some foreign cultivars. High levels of genetic diversity were
detected within the Iranian cultivars, and they showed a clear separation from foreign cultivars, as revealed by unweighted
pair group method with arithmetic averaging and supported by analysis of molecular variance. The lowest amount of polymorphism
was observed in P. atlantica subsp. kurdica, which showed the lowest number of total bands as compared to the other species. This revealed strong genetic erosion of
P. atlantica subsp. kurdica, which reflected a severe decline in habitat and over-exploitation. Based on these findings, strategies are proposed for
the genetic conservation and management of pistachio species and cultivars. 相似文献
139.
Saeed Keyvanshokooh Behrouz Vaziri Ahmad Gharaei Fereidoun Mahboudi Abbas Esmaili-Sari Mohsen Shahriari-Moghadam 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2009,4(4):243-248
Methylmercury (MeHg) is the most toxic form of mercury which is bioaccumulated in the aquatic food chain. It has been shown that one of the main targets of MeHg toxicity is the brain, but there is little knowledge of the molecular mechanisms of its toxic effects. In this work we used a proteomics analysis to determine the changes in the brain proteome of juvenile beluga (Huso huso) exposed to dietary MeHg. The juvenile beluga were fed the diet containing 0.8 ppm MeHg for 70 days. Proteins of the brain tissue were analyzed using two-dimensional electrophoresis and MALDI-TOF/TOF mass spectrometry. We found eight proteins with significant altered expression level in the fish brain exposed to MeHg. These proteins are involved in different cell functions including cell metabolism, protein folding, cell division, and signal transduction. Our results support the idea that MeHg exerts its toxicity through oxidative stress induction and apoptotic effects. They also suggest that chronic MeHg exposure would induce an important metabolic deficiency in the brain. These findings provide basic information to understand possible mechanisms of MeHg toxicity in aquatic ecosystems. 相似文献
140.
Farah Idali Jan Wahlstr?m Benita Dahlberg Mohsen Khademi Tomas Olsson Anders Eklund Johan Grunewald 《Respiratory research》2009,10(1):42