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141.
Schistosoma mansoni: SmLIMPETin, a member of a novel family of invertebrate-only regulatory proteins
Furtado DR de Oliveira FM Morales FC Fantappié MR Rumjanek FD 《Experimental parasitology》2008,120(2):200-204
Eukaryotic LIM domain proteins contain zinc finger forming motifs rich in cysteine and histidine that enable them to interact with other proteins. A cDNA clone isolated from an adult schistosome cDNA library revealed a sequence that coded for a novel class of proteins bearing 6 LIM domains and an N-terminal PET domain, SmLIMPETin. Phylogeny reconstruction of SmLIMPETin and comparison of its sequence to invertebrate homologues and to the vertebrate four-and-a-half LIM domains protein family (FHLs), uncovered a novel LIM domain protein family, the invertebrate LIM and PET domain protein family (LIMPETin). Northern blots, RT-PCR and Western blot showed that SmLIMPETin gene was less expressed in sexually mature adult females compared to sexually immature adult females and sexually mature and immature adult males, and not expressed in schistosomula. 相似文献
142.
The gamma-secretase complex, composed by presenilin, nicastrin, APH-1 and PEN-2, is involved in intramembranous proteolysis of membrane proteins, such as amyloid precursor protein or Notch. Cleavage occurs in multiple cellular compartments. Here, nicastrin mutants containing targeting signals to the endoplasmic reticulum, trans-Golgi network, lysosomes, or plasma membrane have been shown to yield active gamma-secretase complexes with different activities and specificities: wild-type and plasma membrane nicastrin complexes yielded the highest amounts of secreted amyloid-beta peptide (Abeta), predominantly Abeta40, whereas intracellular targeted mutants produced intracellular Abeta, with a comparatively higher amount of Abeta42. These results suggest that compartmental microenvironments play a role in gamma-secretase activity and specificity. 相似文献
143.
p94/calpain 3, a skeletal muscle-specific member of calpain protease family, is characterized by apparent Ca(2+)-independence during exhaustive autolysis and concomitant proteolysis of non-self substrates. The purpose of our study was to comprehensively profile the structural basis of p94 enabling activation in the cytosol without an extra Ca(2+). Ca(2+)-dependent p94 mutants were screened using "p94-trapping", which is an application of yeast genetic reporter system called "proteinase-trapping". Several amino acids were revealed as critical for apparent Ca(2+)-independent p94 activity. These results highlight the importance of conserved amino acids in domain IIb as well as in the p94-specific IS2 region. 相似文献
144.
Holm-Nielsen JB Lomborg CJ Oleskowicz-Popiel P Esbensen KH 《Biotechnology and bioengineering》2008,99(2):302-313
A study of NIR as a tool for process monitoring of thermophilic anaerobic digestion boosted by glycerol has been carried out, aiming at developing simple and robust Process Analytical Technology modalities for on-line surveillance in full scale biogas plants. Three 5 L laboratory fermenters equipped with on-line NIR sensor and special sampling stations were used as a basis for chemometric multivariate calibration. NIR characterisation using Transflexive Embedded Near Infra-Red Sensor (TENIRS) equipment integrated into an external recurrent loop on the fermentation reactors, allows for representative sampling, of the highly heterogeneous fermentation bio slurries. Glycerol is an important by-product from the increasing European bio-diesel production. Glycerol addition can boost biogas yields, if not exceeding a limiting 5-7 g L(-1) concentration inside the fermenter-further increase can cause strong imbalance in the anaerobic digestion process. A secondary objective was to evaluate the effect of addition of glycerol, in a spiking experiment which introduced increasing organic overloading as monitored by volatile fatty acids (VFA) levels. High correlation between on-line NIR determinations of glycerol and VFA contents has been documented. Chemometric regression models (PLS) between glycerol and NIR spectra needed no outlier removals and only one PLS-component was required. Test set validation resulted in excellent measures of prediction performance, precision: r(2) = 0.96 and accuracy = 1.04, slope of predicted versus reference fitting. Similar prediction statistics for acetic acid, iso-butanoic acid and total VFA proves that process NIR spectroscopy is able to quantify all pertinent levels of both volatile fatty acids and glycerol. 相似文献
145.
Do changes in climate patterns in wintering areas affect the timing of the spring arrival of trans‐Saharan migrant birds? 总被引:8,自引:0,他引:8
The life cycles of plants and animals are changing around the world in line with the predictions originated from hypotheses concerning the impact of global warming and climate change on biological systems. Commonly, the search for ecological mechanisms behind the observed changes in bird phenology has focused on the analysis of climatic patterns from the species breeding grounds. However, the ecology of bird migration suggests that the spring arrival of long‐distance migrants (such as trans‐Saharan birds) is more likely to be influenced by climate conditions in wintering areas given their direct impact on the onset of migration and its progression. We tested this hypothesis by analysing the first arrival dates (FADs) of six trans‐Saharan migrants (cuckoo Cuculus canorus, swift Apus apus, hoopoe Upupa epops, swallow Hirundo rustica, house martin Delichon urbica and nightingale Luscinia megarhynchos), in a western Mediterranean area since from 1952 to 2003. By means of multiple regression analyses, FADs were analysed in relation to the monthly temperature and precipitation patterns of five African climatic regions south of the Sahara where species are thought to overwinter and from the European site from where FADs were collected. We obtained significant models for five species explaining 9–41% of the variation in FADs. The interpretation of the models suggests that: (1) The climate in wintering quarters, especially the precipitation, has a stronger influence on FADs than that in the species' potential European breeding grounds. (2) The accumulative effects of climate patterns prior to migration onset may be of considerable importance since those climate variables that served to summarize climate patterns 12 months prior to the onset of migration were selected by final models. (3) Temperature and precipitation in African regions are likely to affect departure decision in the species studied through their indirect effects on food availability and the build‐up of reserves for migration. Our results concerning the factors that affect the arrival times of trans‐Saharan migrants indicate that the effects of climate change are more complex than previously suggested, and that these effects might have an interacting impact on species ecology, for example by reversing ecological pressures during species' life cycles. 相似文献
146.
Chisholm James S. Quinlivan Julie A. Petersen Rodney W. Coall David A. 《Human nature (Hawthorne, N.Y.)》2005,16(3):233-265
Life history theory suggests that in risky and uncertain environments the optimal reproductive strategy is to reproduce early
in order to maximize the probability of leaving any descendants at all. The fact that early menarche facilitates early reproduction
provides an adaptationist rationale for our first two hypotheses: that women who experience more risky and uncertain environments
early in life would have (1) earlier menarche and (2) earlier first births than women who experience less stress at an early
age. Attachment theory and research provide the rationale for our second two hypotheses: that the subjective early experience
of risky and uncertain environments (insecurity) is (3) part of an evolved mechanism for entraining alternative reproductive
strategies contingent on environmental risk and uncertainty and (4) reflected in expected lifespan. Evidence from our pilot
study of 100 women attending antenatal clinics at a large metropolitan hospital is consistent with all four hypotheses: Women
reporting more troubled family relations early in life had earlier menarche, earlier first birth, were more likely to identify
with insecure adult attachment styles, and expected shorter lifespans. Multivariate analyses show that early stress directly
affected age at menarche and first birth, affected adult attachment in interaction with expected lifespan, but had no effect
on expected lifespan, where its original effect was taken over by interactions between age at menarche and adult attachment
as well as age at first birth and adult attachment. We discuss our results in terms of the need to combine evolutionary and
developmental perspectives and the relation between early stress in general and father absence in particular.
This work was supported by The University of Melbourne Department of Obstetrics and Gynaecology.
James S. Chisholm is Professor in the School of Anatomy and Human Biology at the University of Western Australia. He is an
anthropologist whose interests lie in the fields of human behavioral biology, evolutionary ecology, life history theory, and
parental investment theory, where he focuses on infant social-emotional development, the development of reproductive strategies,
and the integration of evolutionary, developmental, and cultural psychology and public health.
Julie A. Quinlivan is Associate Professor in Obstetrics and Gynaecology at the University of Melbourne and Head of the Maternity
Care Program at the Royal Women’s Hospital, Melbourne. Her interests are teenage pregnancy, domestic violence, child abuse
prevention, and high-risk pregnancy.
Rodney W. Petersen is Senior Lecturer in Obstetrics and Gynaecology at the University of Melbourne and Senior Consultant in
Obstetrics and Gynaecology at the Royal Women’s Hospital and Sunshine Hospital in Melbourne. His interests are in psychosocial
aspects of women’s health and cancer.
David A. Coall is a Ph.D. student in the School of Anatomy and Human Biology at the University of Western Australia. His main
interest lies in the application of evolutionary theory within an epidemiological framework. He is currently working on the
synthesis of life history theory, parental investment theory, and parent-offspring conflict theory in exploring factors that
influence variation in human birth weight and placental weight. 相似文献
147.
The first finding of the hydromedusa Hydractinia minima (Trinci, 1903) in plankton of Peter the Great Bay (Sea of Japan) is reported. The hydromedusae are 0.24–0.51 mm in bell diameter and 0.25–0.53 mm in height. The size characteristics of the nematocysts of this species (desmonemes and microbasic euryteles) are given. H. minima is present in the plankton of Peter the Great Bay from June through October at water temperatures of 16.4 to 22°C with the highest mean monthly density of 151 ind./m3. The finding of H. minima in Peter the Great Bay extends the area of this species in the North Pacific to the low-boreal subzone.Original Russian Text Copyright © 2005 by Biologiya Morya, Chaplygina, Dautova. 相似文献
148.
Zaidi N Hermann C Herrmann T Kalbacher H 《Biochemical and biophysical research communications》2008,377(2):327-330
Cathepsin E is an intracellular aspartic protease of the endolysosomal pathway. It has been implicated in several physiological and pathological processes however, its exact functional role is yet to be elucidated. The present review gives an account of the major physiological functions that are associated to cathepsin E by various research groups and highlights the conditions developed in cathepsin E deficiency or the conditions where overexpression of cathepsin E is observed. 相似文献
149.
柴达木盆地西伯利亚白刺和唐古特白刺的氨基酸含量及其营养评价 总被引:17,自引:0,他引:17
对柴达木盆地的西伯利亚白刺和唐古特白刺不同部位中氨基酸含量作了分析比较 ,并进行了营养评价。白刺中富含蛋白质 ,含有 18种氨基酸 ,其中有人体必需的 8种氨基酸 ,白刺果汁中的必需氨基酸含量远高于沙棘果汁。两种白刺的蛋白质和各氨基酸在各部位中含量分布相似 ,但因种的差异 ,第一限制性氨基酸稍有差别。 相似文献
150.
Robert M. Mazo 《Cell biochemistry and biophysics》1987,11(1):19-24
The Green’s function of a random walk on a lattice is defined as the inverse of the operatorK-z1, whereK is the matrix of transition rates and z is an arbitrary complex parameter. The Green’s function for a symmetrical random
walk in one dimension is here explicitly given in closed form for reflecting, periodic, and absorbing boundaries, and also
for an infinite lattice. 相似文献