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121.
Tillering in cereals is a complex process in the regulation of which also signals from the roots in the form of strigolactones
play an important role. The strigolactones are signalling molecules that are secreted into the rhizosphere where they act
as germination stimulants for root parasitic plants and hyphal branching factors for arbuscular mycorrhizal fungi. On the
other hand, they are also transported from the roots to the shoot where they inhibit tillering or branching. In the present
study, the genetic variation in strigolactone production and tillering phenotype was studied in twenty rice varieties collected
from all over the world and correlated with S. hermonthica infection. Rice cultivars like IAC 165, IAC 1246, Gangweondo and Kinko produced high amounts of the strigolactones orobanchol,
2′-epi-5-deoxystrigol and three methoxy-5-deoxystrigol isomers and displayed low amounts of tillers. These varieties induced
high S. hermonthica germination, attachment, emergence as well as dry biomass. In contrast, rice cultivars such as Super Basmati, TN 1, Anakila
and Agee displayed high tillering in combination with low production of the aforementioned strigolactones. These varieties
induced only low S. hermonthica germination, attachment, emergence and dry biomass. Statistical analysis across all the varieties confirmed a positive correlation
between strigolactone production and S. hermonthica infection and a negative relationship with tillering. These results show that genetic variation in tillering capacity is
the result of genetic variation in strigolactone production and hence could be a helpful tool in selecting rice cultivars
that are less susceptible to S. hermonthica infection. 相似文献
122.
123.
In vitro antibiofilm and anti‐adhesion effects of magnesium oxide nanoparticles against antibiotic resistant bacteria 下载免费PDF全文
Sumreen Hayat Saima Muzammil Muhammad Hidayat Rasool Zonaira Nisar Syed Zajif Hussain Anjum Nasim Sabri Saba Jamil 《Microbiology and immunology》2018,62(4):211-220
124.
Kamran Mohamad Reza Zargan Jamil alikhani Hani Keshavarz Hajinoormohamadi Ashkan 《International journal of peptide research and therapeutics》2020,26(4):1819-1828
International Journal of Peptide Research and Therapeutics - Bee venom (BV) has variety of properties, such as anti-inflammatory potential and anti-cancer activity.It has been shown that BV has... 相似文献
125.
In year 2007, a survey was conducted in the Sultanate of Oman in order to evaluate the current environmental awareness of the Omani general public and their willingness to protect the environment. The focus of the survey was to explore the role played by demographic factors (sex, age, and education level) in determining the environmental awareness of the Omani public. The survey was administered to 425 respondents among all areas of the entire Muscat governorate in Oman. The results of the survey revealed that the environmental awareness of the Omani public was related to gender, age, and education level. Males were found to have a higher level of knowledge about environmental issues than females. Males were also more environmentally concerned and tended to engage in more environmental behaviors than females. Younger and more educated respondents tended to be more knowledgeable and concerned about the environment than older and less educated respondents. 相似文献
126.
Miguel A. Chávez-Fumagalli Mariana A.F. Costa Dulcilene M. Oliveira Laura Ramírez Lourena E. Costa Mariana C. Duarte Vivian T. Martins Jamil S. Oliveira Carlos C. Olortegi Pedro Bonay Carlos Alonso Carlos A.P. Tavares Manuel Soto Eduardo A.F. Coelho 《Microbes and infection / Institut Pasteur》2010,12(12-13):967-977
Leishmania chagasi and Leishmania amazonensis are the etiologic agents of different clinical forms of human leishmaniasis in South America. In an attempt to select candidate antigens for a vaccine protecting against different Leishmania species, the efficacy of vaccination using Leishmania ribosomal proteins and saponin as adjuvant was examined in BALB/c mice against challenge infection with both parasite species. Mice vaccinated with parasite ribosomal proteins purified from Leishmania infantum plus saponin showed a specific production of IFN-γ, IL-12 and GM-CSF after in vitro stimulation with L. infantum ribosomal proteins. Vaccinated mice showed a reduction in the liver and spleen parasite burdens after L. chagasi infection. After L. amazonensis challenge, vaccinated mice showed a decrease of the dermal pathology and a reduction in the parasite loads in the footpad and spleen. In both models, protection was correlated to an IL-12-dependent production of IFN-γ by CD4+ and CD8+ T cells that activate macrophages for the synthesis of NO. In the protected mice a decrease in the parasite-mediated IL-4 and IL-10 responses was also observed. In mice challenged with L. amazonensis, lower levels of anti-parasite-specific antibodies were detected. Thus, Leishmania ribosomal proteins plus saponin fits the requirements to compose a pan-Leishmania vaccine. 相似文献
127.
Curtis SL Zambanini A Mayet J McG Thom SA Foale R Parker KH Hughes AD 《American journal of physiology. Heart and circulatory physiology》2007,293(1):H557-H562
In human heart failure the role of wave generation by the ventricle and wave reflection by the vasculature is contentious. The aim of this study was to compare wave generation and reflection in normal subjects with patients with stable compensated heart failure. Twenty-nine normal subjects and 67 patients with heart failure (New York Heart Association class II or III) were studied by noninvasive techniques applied to the common carotid artery. Data were analyzed by wave intensity analysis to determine the nature and direction of waves during the cardiac cycle. The energy carried by an early systolic forward compression wave (S wave) generated by the left ventricle and responsible for acceleration of flow in systole was significantly reduced in subjects with heart failure (P < 0.001), and the timing of the peak of this wave was delayed. In contrast, reflection of this wave was increased in subjects with heart failure (P < 0.001), but the timing of reflections with respect to the S wave was unchanged. The energy of an expansion wave generated by the heart in protodiastole was unaffected by heart failure. The carotid artery wave speed and the augmentation index did not significantly differ between subjects with heart failure compared with normal individuals. The ability of the left ventricle to generate a forward compression wave is markedly impaired in heart failure. Increased wave reflection serves to maintain systolic blood pressure but also places an additional load on cardiac function in heart failure. 相似文献
128.
Asad S Mukhtar Z Nazir F Hashmi JA Mansoor S Zafar Y Arshad M 《Molecular biotechnology》2008,40(2):161-169
A silicon carbide whisker-mediated gene transfer system with recovery of fertile and stable transformants was developed for
cotton (Gossypium hirsutum L.) cv. Coker-312. Two-month-old hypocotyl-derived embryogenic/non-embryogenic calli at different days after subculture were
treated with silicon carbide whiskers for 2 min in order to deliver pGreen0029 encoding GUS gene and pRG229 AVP1 gene, encoding Arabidopsis vacuolar pyrophosphatase, having neomycin phosphotransferaseII (nptII) genes as plant-selectable markers. Three crucial transformation parameters, i.e., callus type, days after subculture and
selection marker concentration for transformation of cotton calli were evaluated for optimum efficiency of cotton embryogenic
callus transformation giving upto 94% transformation efficiency. Within six weeks, emergence of kanamycin-resistant (kmr) callus colonies was noted on selection medium. GUS and Southern blot analysis showed expression of intact and multiple transgene
copies in the transformed tissues. Kanamycin wiping of leaves from T1, T2, and T3 progeny plants revealed that transgenes were inherited in a Mendelian fashion. Salt treatment of T1
AVP1 transgenic cotton plants showed significant enhancement in salt tolerance as compared to control plants. Thus far, this is
first viable physical procedure after particle bombardment available for cotton that successfully can be used to generate
fertile cotton transformants. 相似文献
129.
130.
Strigolactone biosynthesis in Medicago truncatula and rice requires the symbiotic GRAS-type transcription factors NSP1 and NSP2 总被引:1,自引:0,他引:1