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41.
42.
Attracting friends to feast on foes: engineering terpene emission to make crop plants more attractive to herbivore enemies 总被引:3,自引:0,他引:3
When attacked by herbivorous insects or mites, some plant species call on other arthropods for help. They emit mixtures of volatile compounds, dominated by terpenes, to attract carnivorous arthropods that prey on or parasitise herbivores and so reduce further damage. This fascinating defence strategy offers a new, environmentally friendly approach to crop protection. Using recent advances in the biochemistry and molecular genetics of terpene biosynthesis, it should now be possible to engineer crop plants that release terpenes for attracting herbivore enemies. By introducing or selectively altering the existing rate of terpene emission and composition, plant breeders could enable attacked plants to attract enemies and reduce additional herbivory, without compromising the effectiveness of other modes of defence. 相似文献
43.
Clinical Efficacy and Compatibility of Allogeneic Avital Tissue Transplants Sterilized with a Peracetic Acid/Ethanol Mixture 总被引:1,自引:1,他引:0
Pruss A Perka C Degenhardt P Maronna U Büttner-Janz K Paul B Müller K Klumpp C Bruck JC Von Versen R 《Cell and tissue banking》2002,3(4):235-243
In the course of the past 20 years a quantity of approximately 60,000 allogeneic avital tissue grafts sterilized with the
peracetic acid–ethanol method (PES) were transplanted successfully. Based on a retrospective report of clinical experience
of the years 1997–2001 on the overall scope of tissue grafts manufactured by the Tissue Banks of the University Hospital Charité
and the German Institute for Cell and Tissue Replacement, the clinical efficacy and side effects of 18.3% (3.087/16.823) of
all transplants were studied. Cancellous (1.601/3.087) and cortical (291/3.087) bone transplants as well as amnion (1.027/3.087)
constituted the greatest part. In 91% of the examined patients (2.369/2.592) tissue integration ratios ranging from good up
to very well could be observed. The transplant function of defect replacement or of a spacer respectively could be obtained
for all types of tissue. The clinical effect caused by the transplant resulted in more than 99% of the transplants in primary
integration or in the desired aim of the therapy (defect replacement, stabilization in case of palliative operations, etc.).
In less than 1% (9/2.592) of cases a secondary healing occurred for cancellous bone transplantations or, revisional operations
became necessary. In all cases severe side effects, in particular transmission of infectious diseases or transplant rejections,
were not observed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
44.
45.
LEFULESELE N. LEBESA ZEYAUR R. KHAN AHMED HASSANALI JOHN A. PICKETT TOBY J. A. BRUCE MATTHEW SKELLERN KERSTIN KRÜGER 《Physiological Entomology》2011,36(3):220-229
Insect attraction to host plants may be partly mediated by visual stimuli. In the present study, the responses of adult Hycleus apicicornis (Guér.) (Coleoptera: Meloidae) to plant models of different colours, different combinations of two colours, or three hues of blue of different shapes are compared. Single‐colour models comprised the colours sky blue, bright green, yellow, red, white and black. Sky blue (reflecting light in the 440–500 nm region) is the most attractive, followed by white, which reflects light over a broader range (400–700 nm). On landing on sky blue targets, beetles exhibit feeding behaviour immediately. When different hues of blue (of different shapes) are compared, sky blue is preferred over turquoise, followed by dark blue, indicating that H. apicicornis is more attracted to lighter hues of blue than to darker ones. No significant differences are found between the three shapes (circle, square and triangle) tested, suggesting that reflectance associated with colour could be a more important visual cue than shape for host location by H. apicicornis. The preference of H. apicicornis for sky blue can be exploited in designing an attractive trap for its management. 相似文献
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47.
Feng Chen Hani Al-Ahmad Blake Joyce Nan Zhao Tobias G. Köllner Jörg Degenhardt C. Neal Stewart 《Plant Physiology and Biochemistry》2009,47(11-12):1017-1023
Copaifera officinalis, the diesel tree, is known for massive production of oleoresin, mainly composed of sesquiterpene hydrocarbons. In this study, composition of these sesquiterpenes and their concentrations in leaves, stems and roots of C. officinalis at two developmental stages, including the three-week old (TW) seedlings and two-year old (TY) trees, were determined. The leaves of TW seedlings and TY trees contained similar number of sesquiterpenes, which also had comparable concentrations. The stems of TW seedlings had higher concentrations of sesquiterpenes than those of TY trees. In contrast, the number of sesquiterpene species and their concentrations in the roots of TW seedlings were much lower than those in the roots of TY trees. Cluster analysis of sesquiterpenes estimated that there are at least four terpene synthase genes involved in the production of sesquiterpenes in C. officinalis. Because sesquiterpenes are highly volatile, emissions of sesquiterpenes from healthy and wounded TW seedlings were examined using headspace analysis. Whereas very low emission of sesquiterpenes was detected from undamaged plants, the physically injured seedlings emitted a large number of sesquiterpenes, the quality and the relative quantity of which were similar to those in leaves determined using organic extraction. The implications of our findings to the biosynthetic pathways leading to the production of sesquiterpenes as well as their biological roles in C. officinalis are discussed. 相似文献
48.
Wip1-deficient mice are resistant to common cancer genes 总被引:1,自引:0,他引:1
PPM1D encodes WIP1, a serine-threonine phosphatase that had previously been shown to be the driver oncogene of a 17q23 amplicon that is present in approximately 15% of human breast tumors. However, it is unknown whether it has any role in the remaining 85% of breast tumors. A recent study using Wip1-deficient mice revealed that blocking its function significantly impaired RAS and ERBB2-induced breast tumor formation, suggesting that the inhibition of Wip1 could be a broad-spectrum treatment for breast cancer. However, because of the structure of Wip1, the development of small molecule inhibitors is a significant challenge. 相似文献
49.
Gourinath S Degenhardt M Eschenburg S Moore K Delucas LJ Betzel C Singh TP 《Indian journal of biochemistry & biophysics》2001,38(5):298-302
Proteinese K (PK) isolated from Tritirachium album Limber was crystallized with HgCl2 in excess, under microgravity conditions. The intensity data were collected at 4 degrees C to 1.8 A resolution and the final R-factor after refinement for all the reflections was 0.164. Mercury has been found at two sites with partial occupancies (0.4 and 0.6) which are at distances of 2.48 A and 2.58 A respectively from Cys-73 Sgamma. The Cys-73 in the enzyme structure is located close to the active site residue, His-69. This region is completely buried and is not accessible to the solvent. It is rather tightly packed. Therefore, the binding of mercury distorts the stereochemistry of the neighbouring residues including those belonging to the catalytic triad. As a result of this, the Ogamma of Ser-224 is displaced by 0.6 A which causes the inactivation of proteinase K by increasing the H-bond distance to 3.7 A between Ser-224 Ogamma and His-69 Nepsilon2. 相似文献
50.
Fiona J. Charlson Sandra Diminic Crick Lund Louisa Degenhardt Harvey A. Whiteford 《PloS one》2014,9(10)
The world is undergoing a rapid health transition, with an ageing population and disease burden increasingly defined by disability. In Sub-Saharan Africa the next 40 years are predicted to see reduced mortality, signalling a surge in the impact of chronic diseases. We modelled these epidemiological changes and associated mental health workforce requirements. Years lived with a disability (YLD) predictions for mental and substance use disorders for each decade from 2010 to 2050 for four Sub-Saharan African regions were calculated using Global Burden of Disease 2010 study (GBD 2010) data and UN population forecasts. Predicted mental health workforce requirements for 2010 and 2050, by region and for selected countries, were modelled using GBD 2010 prevalence estimates and recommended packages of care and staffing ratios for low- and middle-income countries, and compared to current staffing from the WHO Mental Health Atlas. Significant population growth and ageing will result in an estimated 130% increase in the burden of mental and substance use disorders in Sub-Saharan Africa by 2050, to 45 million YLDs. As a result, the required mental health workforce will increase by 216,600 full time equivalent staff from 2010 to 2050, and far more compared to the existing workforce. The growth in mental and substance use disorders by 2050 is likely to significantly affect health and productivity in Sub-Saharan Africa. To reduce this burden, packages of care for key mental disorders should be provided through increasing the mental health workforce towards targets outlined in this paper. This requires a shift from current practice in most African countries, involving substantial investment in the training of primary care practitioners, supported by district based mental health specialist teams using a task sharing model that mobilises local community resources, with the expansion of inpatient psychiatric units based in district and regional general hospitals. 相似文献