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251.
Stenøien HK Shaw AJ Shaw B Hassel K Gunnarsson U 《Evolution; international journal of organic evolution》2011,65(4):1181-1194
Genetic and morphological similarity between populations separated by large distances may be caused by frequent long-distance dispersal or retained ancestral polymorphism. The frequent lack of differentiation between disjunct conspecific moss populations on different continents has traditionally been explained by the latter model, and has been cited as evidence that many or most moss species are extremely ancient and slowly diverging. We have studied intercontinental differentiation in the amphi-Atlantic peat moss Sphagnum angermanicum using 23 microsatellite markers. Two major genetic clusters are found, both of which occur throughout the distributional range. Patterns of genetic structuring and overall migration patterns suggest that the species probably originated in North America, and seems to have been established twice in Northern Europe during the past 40,000 years. We conclude that similarity between S. angermanicum populations on different continents is not the result of ancient vicariance and subsequent stasis. Rather, the observed pattern can be explained by multiple long-distance dispersal over limited evolutionary time. The genetic similarity can also partly be explained by incomplete lineage sorting, but this appears to be caused by the short time since separation. Our study adds to a growing body of evidence suggesting that Sphagnum, constituting a significant part of northern hemisphere biodiversity, may be more evolutionary dynamic than previously assumed. 相似文献
252.
Pikó B Kremer IM Rahoty P Bassam A Dimák S Kis A Csiffári M Rus-Gal P Szabó Z Veréb B Zsilak J 《Magyar onkologia》2011,55(3):164-169
The risk of venous thromboembolic events (VTE) in cancer patients is higher than in the general population. Treatment may also increase this risk in these patients. Based on the appropriate criteria (of which the most important are the current ministerial guidelines) thrombosis prophylaxis should be started (given that there is no contraindication) on these patients and be continued while they are at risk. In the event of permanent risk thrombosis prophylaxis should be given lifelong. The drug of choice is low-molecular-weight heparin (LMWH) which is safer and more effective than the oral vitamin K antagonists. Platelet aggregation inhibitors have proved unsuccessful in this patient group. The evidence so far suggests that LMWH (during VTE prophylaxis) can have a positive impact on the course of cancer and perhaps it will be registered under the indication section for cancer patients in the future. 相似文献
253.
Pikó B Rahóty P Krémer I Zsilák J Török E Bassam A Csiffári M Dimák S Kis A Rus-Gal P Szabó Z Veréb B Puskásné Szatmári K 《Magyar onkologia》2011,55(4):244-249
Recognition of the commonly encountered colorectal cancer (CRC) generally begins and takes place because of and based on symptoms and signs, due to the unsettled screening of this type of cancer. Sometimes, because of advanced stage cancer urgent surgical intervention could become necessary and, if this is the case, there is no time and possibility for searching for an eventual second tumor and perhaps the patient's status does not permit performing intraoperative investigations either. The incidence of multiple colon cancer is considered to be between 2.5 and 30% according to the literature. That is why one should exclude them even in the absence of pre- and intraoperative investigations and complaints. On the other hand, colonoscopy and perhaps irrigoscopy of seemingly healthy followed-up patients is mandatory. In the case of the presence of complaints/symptoms denoting impaired intestinal passage seen in a followed-up patient or during the adjuvant setting or metastatic/recurrent disease, treatment and even during hospice care we should evaluate the possibility of a second metachronous tumor. Moreover, if there is no urgency, the multidisciplinary team (oncoteam) should recommend the adequate treatment by balancing gain/utility and risk. 相似文献
254.
Clusia blattophila (Clusiaceae) is described as a new species. It is distinguished from related species in C. sect. Oedematopus by e.g. the relatively large and reflexed petals and from other Clusia spp. by having fewer (6–16) stamens and only four petals. Unique traits are the almost sessile inflorescence and the presence of a secretory pit at the floral apex in staminate flowers. The species grows epilithically and is known only from the Nouragues inselberg, a massive granite outcrop in eastern French Guiana. The name refers to its cockroach pollinators. 相似文献
255.
Drug-induced systemic lupus erythematosus (SLE) is a rare complication of therapies with some drugs. Breaking out after months or years of therapy with a certain drug, its occurrence is likely to increase with the duration of the medication and the cumulative quantity of the drug. The symptoms of this syndrome include, in particular, arthralgia, myalgia, fever, serositis, skin exanthema and production of antinuclear (ANA) antibodies. In contrast to SLE, its symptoms gradually abate after discontinuation of the inducing agent. The authors describe the case of a 43-year-old patient suffering from multiple sclerosis who experienced drug-induced SLE after 8-year application of interferon (IFN) beta-1b. 相似文献
256.
Kucejova B Peña-Llopis S Yamasaki T Sivanand S Tran TA Alexander S Wolff NC Lotan Y Xie XJ Kabbani W Kapur P Brugarolas J 《Molecular cancer research : MCR》2011,9(9):1255-1265
mTOR complex 1 (mTORC1) is implicated in cell growth control and is extensively regulated. We previously reported that in response to hypoxia, mTORC1 is inhibited by the protein regulated in development and DNA damage response 1 (REDD1). REDD1 is upregulated by hypoxia-inducible factor (HIF)-1, and forced REDD1 expression is sufficient to inhibit mTORC1. REDD1-induced mTORC1 inhibition is dependent on a protein complex formed by the tuberous sclerosis complex (TSC)1 and 2 (TSC2) proteins. In clear-cell renal cell carcinoma (ccRCC), the von Hippel-Lindau (VHL) gene is frequently inactivated leading to constitutive activation of HIF-2 and/or HIF-1, which may be expected to upregulate REDD1 and inhibit mTORC1. However, mTORC1 is frequently activated in ccRCC, and mTORC1 inhibitors are effective against this tumor type; a paradox herein examined. REDD1 was upregulated in VHL-deficient ccRCC by in silico microarray analyses, as well as by quantitative real-time PCR, Western blot, and immunohistochemistry. Vhl disruption in a mouse model was sufficient to induce Redd1. Using ccRCC-derived cell lines, we show that REDD1 upregulation in tumors is VHL dependent and that both HIF-1 and HIF-2 are, in a cell-type-dependent manner, recruited to, and essential for, REDD1 induction. Interestingly, whereas mTORC1 is responsive to REDD1 in some tumors, strategies have evolved in others, such as mutations disrupting TSC1, to subvert mTORC1 inhibition by REDD1. Sequencing analyses of 77 ccRCCs for mutations in TSC1, TSC2, and REDD1, using PTEN as a reference, implicate the TSC1 gene, and possibly REDD1, as tumor suppressors in sporadic ccRCC. Understanding how ccRCCs become refractory to REDD1-induced mTORC1 inhibition should shed light into the development of ccRCC and may aid in patient selection for molecular-targeted therapies. 相似文献
257.
Marija Bošković Tomaž Vovk Marko Saje Katja Goričar Vita Dolžan Blanka Kores Plesničar Iztok Grabnar 《Neurochemical research》2013,38(2):433-442
There is a growing body of evidence confirming the involvement of oxidative stress and inflammation in pathogenesis of schizophrenia. Inter-individual variation in antioxidant capacity caused by different genetic profile could potentially influence patient’s susceptibility to oxidative damage. In this study we evaluated the polymorphisms of manganese superoxide dismutase SOD2Val16Ala, glutathione peroxidase GPX1Pro200Leu, catalase CAT-262C>T and CATc.66+78C>T, and tumour necrosis factor-alpha TNF-308G>A by assessing their association with biomarkers of oxidative stress, neurochemistry, psychopathology of schizophrenia and extrapyramidal symptoms in Caucasian schizophrenia patients treated with haloperidol depot. TNF-308G>A was associated with the increased risk of parkinsonism. No major role of polymorphism of SOD2Val16Ala, CAT-262C>T nor GPX1Pro200Leu in psychopathology of schizophrenia or extrapyramidal symptoms was observed. SOD2Val16Ala polymorphism was associated with dopamine plasma concentration and blood concentration ratio between reduced and oxidised form of glutathione, while GPX1Pro200Leu was related with concentration of reduced glutathione. CATc.66+78C>T was associated with noradrenaline plasma concentration and PANSS negative score. PANSS positive and general scores, were associated with the increased risk of tardive dyskinesia. PANSS positive, negative, and general scores, and GAF score were all associated with the increased risk of akathisia. 相似文献
258.
259.
In spite of Slovenia’s very high biodiversity, it has only a few animal groups that have been significantly investigated and are well known in this area. Slovenian researchers have studied only about half of the species known to be living in the country (Mršić 1997), but among well investigated species are centipedes. All available data about centipedes in Slovenia collected from 1921 to 2014 have been consolidated and constitute a general electronic database called “CHILOBIO”, which was created to provide an easy overview of the Slovenian centipede fauna and to allow entry and interpretation of new data collected in future research. The level of investigation has been studied with this database, in conjunction with a geographic information system (GIS). In the study period, 109 species were identified from 350 localities in 109 of the 236 UTM 10 × 10 km quadrants which cover the study area. The south-central part of the country has been the subject of the best investigations, whereas there is an absence of data from the south-eastern, eastern and north-eastern regions The highest number of species (52) has been recorded near the Iška valley (Central Slovenia, quadrant VL68). In 48% of the UTM quadrants investigated fewer than 10 species were recorded and just 5 species were found in one locality. Seventeen species were reported only in the Dinaric region, 4 in the Prealpine-subpannonian region and 7 in the Primorska-submediterranean region. 相似文献
260.
Ondřej Koukol Blanka Beňová Magda Vosmanská Tomáš Frantík Miroslav Vosátka Marcela Kovářová 《Plant and Soil》2008,303(1-2):151-159
Different components of functional biodiversity, such as functional type richness and composition, have been reported to affect
the decomposition of litter mixtures. In spite of the numerous reports of these effects, mechanisms underlying patterns of
decomposition in litter mixtures are still unclear. We analyzed whether mixture decomposition was affected by: (a) the number
of species in the mixture (mixture richness); and (b) the mixture’s functional composition (% of fast- vs. slow-decomposing
species included in the mixture). We then tested if variation between observed and expected values of decomposition in mixtures
was associated to: (c) the initial litter characteristics of the component species (initial nitrogen, lignin, cellulose and
hemicellulose content of litters); and (d) the chemical heterogeneity of the mixtures (variation in the same chemical compounds
between the components in each mixture). When up to 5 species representing different functional types were included, both
species richness and functional composition showed statistically significant non-additive, and in general positive, effects
on litter mixture decomposition. The positive effect of mixture richness on decomposition did not disappear, but was much
less marked, when considering mixture with slow-decomposing species only. Although the main driver of decomposition in a mixture
is still the average decomposability of the component species (itself largely determined by litter quality), the species interactions
in a mixture add a consistent source of variability that is worth considering when predicting the decomposability of a given
mixture. We showed that a greater positive difference between observed decomposition rates and that expected from its component
species alone was found in mixtures with higher mean nitrogen content and a higher heterogeneity in non-labile compounds.
Our results offer quantitative proof that litter chemical heterogeneity, as well as the mean quality of the mixture, can affect
the decomposability in litter mixtures. 相似文献