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961.
Caroline Blondeau Annegret Pelchen-Matthews Petra Mlcochova Mark Marsh Richard S. B. Milne Greg J. Towers 《Journal of virology》2013,87(24):13124-13133
Tetherin is a broadly active antiviral effector that works by tethering nascent enveloped virions to a host cell membrane, thus preventing their release. In this study, we demonstrate that herpes simplex virus 1 (HSV-1) is targeted by tetherin. We identify the viral envelope glycoprotein M (gM) as having moderate anti-tetherin activity. We show that gM but not gB or gD efficiently removes tetherin from the plasma membrane and can functionally substitute for the human immunodeficiency virus type 1 (HIV-1) Vpu protein, the prototypic viral tetherin antagonist, in rescuing HIV-1 release from tetherin-expressing cells. Our data emphasize that tetherin is a broadly active antiviral effector and contribute to the emerging hypothesis that viruses must suppress or evade an array of host cell countermeasures in order to establish a productive infection. 相似文献
962.
Intrinsic factor (IF) was first identified as a component of the gastric mucosa that reacted with an extrinsic factor, later discovered to be vitamin B12 (VB12). IF has been extensively characterized, and its cloned cDNA used to produce sufficient IF to produce high quality antibodies, and to elucidate its 3-dimensional structure bound to cobalamin (Cbl, VB12). The absorption of the IF–Cbl complex involves internalization by endocytosis, incorporation into multivesicular/lysosomal bodies, release of Cbl by lysosomal proteolysis and pH effects, with subsequent binding to transcobalamin (TC). Hereditary IF deficiency is rare, consistent with the need for IF to absorb Cbl, a vitamin essential for cell replication. When mutations occur, they are most often associated with loss of function, but some mutations occur outside the coding region. The IF-mediated intestinal uptake of Cbl has been harnessed for use as a transporter for peptides, proteins and even nanoparticles. Nanoparticle (NP) technology has produced Cbl-coated NPs that can incorporate peptides (insulin, IgG) that can be absorbed orally to function as hormones and antibodies in rodent models, but these systems are not yet ready for clinical use. 相似文献
963.
Jim Waterhouse Laura Bailey Faye Tomlinson Benjamin Edwards Greg Atkinson Thomas Reilly 《Chronobiology international》2013,30(6):1069-1092
Some factors influencing food intake and subjective responses to meals were assessed in 2 groups (n=40 and n=36) of healthy university students. Both groups were studied for 6 days and included both “structured” and “unstructured” times. A questionnaire was completed by all subjects at 3 h intervals while awake. The questionnaires asked the subjects to state the factors that led them to choose to eat or not to eat a meal in the previous 3 h. If they ate a meal, they were required to describe the type of meal eaten and their responses to it—their hunger before it, their enjoyment of the meal itself, and their degree of satisfaction afterwards. Subjects were also asked to describe the type of meal that they would like to have eaten (the desired meal) in the absence of any restraints due to time pressure, cost, and so on. In the first group, 3 “structured” (working) and 3 “unstructured” (rest) days were chosen. Consistant with our previous studies, structured days, as compared to unstructured days, were associated with smaller meals and less positive subjective responses to them. Also, the meals that were eaten were often smaller than those that were desired, or were even missed altogether, due to time pressure. Not only were the meals eaten on unstructured days larger and rated, to by the subjects more positively, but also there was an additional positive effect if the meal played a social role. In the second group, 6 days were chosen, during which there were structured and unstructured 3 h periods. Many of the findings (with regard to reasons for eating or not eating a meal, and the effect of meal size upon subjective responses to it, for example) were the same as in the first group. However, the effect of structured vs. unstructured 3 h periods was significantly less marked than the effect of structured vs. unstructured days that had been found in the first group, and effects due to social factors and time pressure were less reliably present. The results indicate that food intake is affected by whether the whole or only part of the day is “structured” or “unstructured.” These findings might be relevant to some problems faced by the workforce, in general, and by night workers, in particular. 相似文献
964.
Interferon tau (IFNT), the pregnancy recognition signal in ruminants, abrogates the uterine luteolytic mechanism to ensure maintenance of function for the corpora lutea to produce progesterone (P4). IFNT also suppresses expression of classical IFN-stimulated genes by uterine lumenal epithelium (LE) and superficial glandular (sGE) epithelium but, acting in concert with progesterone, affects expression of a multitude of genes critical to growth and development of the conceptus. The LE and sGE secrete proteins and transport nutrients into the uterine lumen necessary for conceptus development, pregnancy recognition signaling, and implantation. Secretions include arginine and secreted phosphoprotein 1 (SPP1). Arginine can be metabolized to nitric oxide and to polyamines or act directly to activate the mechanistic target of rapamycin cell signaling pathway to stimulate proliferation, migration, and mRNA translation in trophectoderm cells. SPP1 binds alphavbeta3 and alpha5beta1 integrins to induce focal adhesion assembly, adhesion, and migration of conceptus trophectoderm cells during implantation. Thus, arginine and SPP1 mediate growth, migration, cytoskeletal remodeling, and adhesion of trophectoderm essential for pregnancy recognition signaling and implantation. This minireview focuses on components of histotroph that affect conceptus development in the ewe. 相似文献
965.
966.
A comparison of various mating disruption technologies for control of two internally feeding Lepidoptera in apples 总被引:1,自引:0,他引:1
Eric Bohnenblust Larry A. Hull Greg Krawczyk 《Entomologia Experimentalis et Applicata》2011,138(3):202-211
Sex pheromone mating disruption (MD) is an approach used to control several moth pest species of pome fruit by disrupting the ability of the males to find females and consequently prevent mating. The following experiments were performed to determine the effectiveness of several new and experimental sex pheromone MD technologies, and dispenser densities for simultaneous control of the codling moth (CM), Cydia pomonella (L.), and the oriental fruit moth (OFM), Grapholita molesta (Busck) (both Lepidoptera: Tortricidae), in Pennsylvania apple orchards. In one study, three MD approaches to control CM and oriental fruit moth – CM and OFM Disrupt Micro‐Flakes, Isomate CM/OFM TT, and both a CideTrak OFM and a CideTrak CM dispenser containing both codlemone and pear ester – and an insecticides‐only treatment were compared over the course of 2 years. In the other studies, the efficacy of several CheckMate Duel dispenser densities (i.e., 250, 375, 425, and 500 dispensers ha?1) were compared against Isomate CM/OFM TT, and an insecticides‐only treatment. The CideTrak CM/pear ester combination and Isomate CM/OFM TT treatments both substantially reduced CM captures in traps in 2007 and 2008. Meanwhile, OFM trap shutdown was highest in the CheckMate Duel densities of 375 (99.9 ± 0.08%) and 500 dispensers ha?1 (98.9 ± 0.07%) and the Isomate CM/OFM TT treatment (98.0 ± 1.13%), and lowest in the 250 dispensers ha?1 density treatment (94.3 ± 3.23%). In orchards where OFM is the dominant pest species, a CheckMate Duel dispenser density of 375 ha?1 is necessary for effective control, whereas higher densities are needed to control CM. 相似文献
967.
Alireza Houshmandfar Noboru Ota Garry J. O'Leary Bangyou Zheng Yang Chen Sabine Tausz‐Posch Glenn J. Fitzgerald Richard Richards Greg J. Rebetzke Michael Tausz 《Global Change Biology》2020,26(7):4056-4067
Reducing the number of tillers per plant using a t iller in hibition (tin) gene has been considered as an important trait for wheat production in dryland environments. We used a spatial analysis approach with a daily time‐step coupled radiation and transpiration efficiency model to simulate the impact of the reduced‐tillering trait on wheat yield under different climate change scenarios across Australia's arable land. Our results show a small but consistent yield advantage of the reduced‐tillering trait in the most water‐limited environments both under current and likely future conditions. Our climate scenarios show that whilst elevated [CO2] (e[CO2]) alone might limit the area where the reduced‐tillering trait is advantageous, the most likely climate scenario of e[CO2] combined with increased temperature and reduced rainfall consistently increased the area where restricted tillering has an advantage. Whilst long‐term average yield advantages were small (ranged from 31 to 51 kg ha?1 year?1), across large dryland areas the value is large (potential cost‐benefits ranged from Australian dollar 23 to 60 MIL/year). It seems therefore worthwhile to further explore this reduced‐tillering trait in relation to a range of different environments and climates, because its benefits are likely to grow in future dry environments where wheat is grown around the world. 相似文献
968.
Masha T. van der Sande Helge Bruelheide Wayne Dawson Jürgen Dengler Franz Essl Richard Field Sylvia Haider Mark van Kleunen Holger Kreft Joern Pagel Jan Pergl Oliver Purschke Petr Pyek Patrick Weigelt Marten Winter Fabio Attorre Isabelle Aubin Erwin Bergmeier Milan Chytrý Matteo Dainese Michele De Sanctis Jaime Fagundez Valentin Golub Greg R. Guerin Alvaro G. Gutirrez Ute Jandt Florian Jansen Borja Jimnez‐Alfaro Jens Kattge Elizabeth Kearsley Stefan Klotz Koen Kramer Marco Moretti Ülo Niinemets Robert K. Peet Josep Penuelas Petr Petík Peter B. Reich Brody Sandel Marco Schmidt Maria Sibikova Cyrille Violle Timothy J. S. Whitfeld Thomas Wohlgemuth Tiffany M. Knight 《Global Ecology and Biogeography》2020,29(2):281-294
969.
Zhi Zhang Benjamin Hsieh Amy Poe Julie Anderson Karen Ocorr Greg Gibson Rolf Bodmer 《PloS one》2013,8(4)
Natural populations of the fruit fly, Drosophila melanogaster, segregate genetic variation that leads to cardiac disease phenotypes. One nearly isogenic line from a North Carolina peach orchard, WE70, is shown to harbor two genetically distinct heart phenotypes: elevated incidence of arrhythmias, and a dramatically constricted heart diameter in both diastole and systole, with resemblance to restrictive cardiomyopathy in humans. Assuming the source to be rare variants of large effect, we performed Bulked Segregant Analysis using genomic DNA hybridization to Affymetrix chips to detect single feature polymorphisms, but found that the mutant phenotypes are more likely to have a polygenic basis. Further mapping efforts revealed a complex architecture wherein the constricted cardiomyopathy phenotype was observed in individual whole chromosome substitution lines, implying that variants on both major autosomes are sufficient to produce the phenotype. A panel of 170 Recombinant Inbred Lines (RIL) was generated, and a small subset of mutant lines selected, but these each complemented both whole chromosome substitutions, implying a non-additive (epistatic) contribution to the “disease” phenotype. Low coverage whole genome sequencing was also used to attempt to map chromosomal regions contributing to both the cardiomyopathy and arrhythmia, but a polygenic architecture had to be again inferred to be most likely. These results show that an apparently simple rare phenotype can have a complex genetic basis that would be refractory to mapping by deep sequencing in pedigrees. We present this as a cautionary tale regarding assumptions related to attempts to map new disease mutations on the assumption that probands carry a single causal mutation. 相似文献
970.
Pablo Tsukayama Jorge H. Nú?ez Maxy De Los Santos Valeria Soberón Carmen M. Lucas Greg Matlashewski Alejandro Llanos-Cuentas Marianela Ore G. Christian Baldeviano Kimberly A. Edgel Andres G. Lescano Paul C. F. Graf David J. Bacon 《PLoS neglected tropical diseases》2013,7(1)
In South America, various species of Leishmania are endemic and cause New World tegumentary leishmaniasis (NWTL). The correct identification of these species is critical for adequate clinical management and surveillance activities. We developed a real-time polymerase chain reaction (PCR) assay and evaluated its diagnostic performance using 64 archived parasite isolates and 192 prospectively identified samples collected from individuals with suspected leishmaniasis enrolled at two reference clinics in Lima, Peru. The real-time PCR assay was able to detect a single parasite and provided unambiguous melting peaks for five Leishmania species of the Viannia subgenus that are highly prevalent in South America: L. (V.) braziliensis, L. (V.) panamensis, L. (V.) guyanensis, L. (V.) peruviana and L. (V.) lainsoni. Using kinetoplastid DNA-based PCR as a gold standard, the real-time PCR had sensitivity and specificity values of 92% and 77%, respectively, which were significantly higher than those of conventional tests such as microscopy, culture and the leishmanin skin test (LST). In addition, the real-time PCR identified 147 different clinical samples at the species level, providing an overall agreement of 100% when compared to multilocus sequence typing (MLST) data performed on a subset of these samples. Furthermore, the real-time PCR was three times faster and five times less expensive when compared to PCR - MLST for species identification from clinical specimens. In summary, this new assay represents a cost-effective and reliable alternative for the identification of the main species causing NWTL in South America. 相似文献