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991.
A total of 74 Streptococcus thermophilus isolates collected between 1948 and 2005 from different environments were investigated to assess erythromycin, clindamycin,
streptomycin, gentamicin, tetracycline and ampicillin susceptibility by means of microdilution, Etest and disk diffusion methods.
For this purpose a new S. thermophilus Susceptibility test Medium (SSM) was developed. This medium allowed a better identification of strains with atypical tetracycline
resistance. The recipe is a mixed formulation of Iso-Sensitest medium (90% v/v) and M17 medium (10% v/v) supplemented with
lactose (0.5% w/v). The overall agreement of the techniques was good with exception of tetracycline, for which Etest provided
lower MICs than the microdilution method. Most strains were susceptible to all the antibiotics tested while a few erythromycin,
tetracycline and streptomycin resistant strains were detected. 相似文献
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A Real‐World Multicentre Retrospective Study of Paclitaxel‐Bevacizumab and Maintenance Therapy as First‐Line for HER2‐Negative Metastatic Breast Cancer
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Teresa Gamucci Lucia Mentuccia Clara Natoli Isabella Sperduti Alessandra Cassano Andrea Michelotti Luigi Di Lauro Domenico Sergi Alessandra Fabi Maria G. Sarobba Paolo Marchetti Maddalena Barba Emanuela Magnolfi Marcello Maugeri‐Saccà Ernesto Rossi Valentina Sini Antonino Grassadonia Domenica Pellegrini Antonino Astone Cecilia Nisticò Franco Angelini Angela Vaccaro Arianna Pellegrino Claudia De Angelis Michela Palleschi Luca Moscetti Ilaria Bertolini Simonetta Buglioni Antonio Giordano Laura Pizzuti Patrizia Vici 《Journal of cellular physiology》2017,232(6):1571-1578
Bevacizumab in combination with taxanes in HER2‐negative metastatic breast cancer (MBC) patients has shown improved progression‐free survival (PFS), despite the lack of clear overall survival (OS) benefit. We performed a retrospective analysis to evaluate the impact of paclitaxel‐bevacizumab and of maintenance therapy with bevacizumab (BM) and endocrine therapy (ET) in the real‐world practice. We identified 314 HER2‐negative MBC patients treated in 12 cancer centers. Overall, the median PFS and OS were 14 and 40 months, respectively. Among the 254 patients potentially eligible for BM, 183 received BM after paclitaxel discontinuation until progression/toxicity. PFS and OS were improved in patients who had received BM in comparison with those potentially eligible but who did not receive BM (P< 0.0001 and P = 0.001, respectively). Results were confirmed when adjusting for propensity score. Among the 216 hormone‐receptor positive patients eligible for BM, a more favorable PFS and OS were observed when maintenance ET was administered (P < 0.0001). Multivariate analysis showed that PS, BM, number of disease sites and maintenance ET were related to PFS, while response and maintenance ET were related to OS. In hormone‐receptor positive patients, BM produced a significant PFS and a trend towards OS benefit only in absence of maintenance ET (P = 0.0007 and P = 0.06, respectively). In the triple‐negative subgroup, we observed a trend towards a better OS for patients who received BM (P = 0.06), without differences in PFS (P = 0.21). Our results confirmed the efficacy of first‐line paclitaxel‐bevacizumab in real‐world practice; both BM and maintenance ET significantly improved PFS and OS compared to no maintenance therapies. J. Cell. Physiol. 232: 1571–1578, 2017. © 2016 Wiley Periodicals, Inc. 相似文献
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Giuseppe Mazza Francesco Paoli Agostino Strangi Giulia Torrini Leonardo Marianelli Giuseppino Sabbatini Peverieri Francesco Binazzi Giovanni Bosio Stefano Sacchi Claudia Benvenuti Davide Venanzio Emanuela Giacometto Pio F. Roversi George O. PoinarJr. 《Systematic parasitology》2017,94(8):915-926
A new species of mermithid nematode, Hexamermis popilliae n. sp. (Nematoda: Mermithidae) is described from the Japanese beetle Popillia japonica Newman in Italy, an area of new introduction for this invasive pest. The combination of the following characters separates H. popilliae from other members of the genus Hexamermis Steiner, 1924: adult head obtuse; amphidial pouches slightly posterior to lateral head papillae in female but adjacent to lateral head papillae in males; amphidial openings large, well developed; amphidial pouches elliptical in females and oblong in males; cuticular vulvar cone well developed, vulvar lips greatly reduced or lacking, vagina curved at tip where meeting uteri, without reverse bend (not S-shaped), spicules slightly curved, with a slight bend in the basal portion, approximately equal to body width at cloaca. This is the first record of a species of Hexamermis parasitizing the Japanese beetle Popillia japonica. The only previous mention of mermithid nematodes from P. japonica was an undescribed species of Psammomermis in North America. Hexamermis popilliae will be evaluated as a potential biological control agent in an integrated control program of the Japanese beetle in Italy. 相似文献
997.
Methane yield of biomass from extensive grassland is affected by compositional changes induced by order of arrival
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Philipp von Gillhaussen Emanuela W. A. Weidlich Heike Sträuber Hauke Harms Vicky M. Temperton 《Global Change Biology Bioenergy》2017,9(10):1555-1562
Low‐input grassland biomass from marginal and other slightly more fertile sites can be used for energy production without competing with food or fodder production. The effect of grassland diversity on methane yield has received some attention, but we do not know how community assembly may affect methane yield from grassland biomass. However, methane yields determine the potential economic value of a bioenergy substrate. Hence, a better understanding of how plant community assembly affects methane yield would be important. We measured biomass production and methane yield in the second year of a grassland field experiment which manipulated the order of arrival of different plant functional groups (forbs, grasses or legumes sown first and all sown simultaneously) and sown diversity (9 vs. 21 species). The order of arrival of the plant functional groups significantly determined the relative dominance of each group which in turn mainly explained the variance in aboveground biomass production. Differences in area‐specific methane yields were driven by differences in biomass production and which plant functional groups dominated a plot. When grasses were sown first, legumes and grasses codominated a plot and the highest area‐specific methane yield was obtained. Overall, the results indicate that altering the order of arrival affected the community functional and species composition (and hence methane yields) much more than sown diversity. Our study shows that a combined use of positive biodiversity effects and guided plant community assembly may be able to optimize methane yields under field conditions. This may allow a guided, sustainable, and lucrative use of grassland biomass for biogas production in the future. 相似文献
998.
A novel synthetic chemical CGA 245704 [benzo (1,2,3) thiadiazole-7-carbothioic acid S methyl ester (acibenzolar-S-methyl) (BTH)] applied as a soil drench and foliar spray was shown to provide good protection against Plasmopara helianthi in sunflower plants. Soil drenches at the rates of 150 and 200 mg/kg soil, were applied 3 days before the inoculation and induced high levels of protection (80–82%) against downy mildew. At the highest concentrations (up to 300 mg/kg soil) about 90% protection was observed but at these rates phytotoxic symptoms were noted. This compound also provided good protection against P. helianthi when applied 1 day before the inoculation as well as when applied 1 day post-inoculation. The chemical had no antifungal activity in vitro against P. helianthi . In addition the combination of CGA 245704 and metalaxyl, as a seed dressing at low rates, provided a high level of control against the disease; however, the activity of this combination was not significantly different from metalaxyl alone. CGA 245704 applied as a soil drench and foliar spray also protected sunflower plants from P. helianthi foliar infection. 相似文献
999.
Michael Kemp Emanuela Handman Kåre Kemp Ahmed Ismail Mustafa D Mustafa Anuar Y Kordofani Klaus Bendtzen Arsalan Kharazmi Thor G Theander 《FEMS immunology and medical microbiology》1998,20(3):209-218
The promastigote surface antigen-2 (PSA-2) is a Leishmania parasite antigen, which can induce Th1-mediated protection against murine leishmaniasis when used as a vaccine. To evaluate PSA-2 as a human vaccine candidate the specific T-cell response to PSA-2 was characterised in individuals immune to cutaneous leishmaniasis. Peripheral blood mononuclear cells from Sudanese individuals with a past history of self-healing cutaneous leishmaniasis proliferated vigorously in response to PSA-2 isolated from Leishmania major, whereas the antigen did not activate cells from presumably unexposed Danes. Peripheral blood mononuclear cells from individuals with previous L. major infection had varying proliferative responses to PSA-2 derived from L. donovani promastigotes. Peripheral blood mononuclear cells activated by PSA-2 from L. major produced high amounts of interferon-γ and tumour necrosis factor-β, and little interleukin-4, thereby showing a Th1 cytokine pattern. Parallel cultures showed clear Th1 and Th2 response patterns to purified protein derivative of tuberculin or tetanus toxoid, respectively. Flow cytometric analysis revealed that PSA-2 induced blastogenesis in the CD3 positive population and that these cells were the major source of interferon-γ. The results show that Th1-like cells recognising PSA-2 are expanded during infection by L. major and that they maintain their Th1-like cytokine profile upon reactivation in vitro. Since immunity to cutaneous leishmaniasis is mediated by antigen-specific Th1-like cells, PSA-2 might be considered a vaccine candidate for human leishmaniasis. 相似文献
1000.