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101.
Treatment with 60% hydrofluoric acid (HF) removed most of the phosphorus and small amounts of mannan, glucan and protein from walls of two non-flocculent strains (NCYC366 and NCYC1004) and two flocculent strains (NCYC1005 and NCYC1063) of Saccharomyces cerevisiae. Organisms of all strains showed increased flocculating ability following HF treatment. Flocculation of untreated organisms of NCYC1005 and NCYC1063, and of HF-treated organisms of all four strains, declined appreciably when they were washed in deionized water, with or without EDTA, and the flocculation was measured in deionized water instead of in 0-05 M-sodium acetate containing Ca2+. Treatment with 1,2-epoxypropane also caused a decrease in the flocculating ability of these organisms. Extracting the lipids from organisms of strains NCYC366 and NCYC1004 had no effect on their flocculating ability, but decreased the flocculating ability of organisms of strains NCYC1005 and NCYC1063. pH-electrophoretic mobility curves of untreated and HF-treated organisms confirmed the loss of wall phosphate by HF treatment, and indicated that HF treatment had little effect on the content of protein carboxyl groups in the outer wall layers. Mannose at 0-22 M completely prevented floc formation by organisms of strain NCYC1063; but, even at 0-33 M, it had very little effect on floc formation by HF-treated organisms of strains NCYC366 and NCYC1063. Organisms of all four strains bound fluorescein-conjugated concanavalin A to the same extent after treatment with HF as before, but this treatment led to a greatly diminished binding of of fluorescein-conjugated antiserum raised against organisms of strain NCYC366. The results indicate that phosphodiester linkages in yeast-wall mannan are not involved in bride formation through Ca2+ during floc formation and that this arises principally through carboxyl groups. 相似文献
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104.
We present 3 cases of carotid sinus compression with cardiac asystole which occurred in healthy patients undergoing routine rhytidectomies. The mechanism is discussed and suggestions are made regarding preoperative evaluation and operative management. 相似文献
105.
Aisha Sumbul Rizwan Ali Ansari Rose Rizvi Irshad Mahmood 《Saudi Journal of Biological Sciences》2020,27(12):3634-3640
Stressor (biotic as well as abiotic) generally hijack the plant growth and yield characters in hostile environment leading to poor germination of the plants and yield. Among the plant growth promoting rhizobacteria, Azotobacter spp. (Gram-negative prokaryote) are considered to improve the plant health. Various mechanisms are implicated behind improved plant health in Azotobacter spp. inoculated plants. For example, acceleration of phytohormone like Indole-3-Acetic Acid production, obviation of various stressors, nitrogen fixation, pesticides and oil globules degradation, heavy metals metabolization, etc. are the key characteristics of Azotobacter spp. action. In addition, application of this bacteria has also become helpful in the reclamation of soil suggesting to be a putative agent which can be used in the transformation of virgin land to fertile one. Application of pesticides of chemical origin are being put on suspension mode as the related awareness program is still on. As far as the limitations of this microbe is concerned, commercial level formulations availability is still a great menace. Present review has been aimed to appraise the researchers pertaining to utility of Azotobacter spp. in the amelioration of plant health in sustainable agroecosystem. The article has been written with the target to gather maximum information into single pot so that it could reach to the dedicated researchers. 相似文献
106.
Jacob A. Toth George M. Stack Ali R. Cala Craig H. Carlson Rebecca L. Wilk Jamie L. Crawford Donald R. Viands Glenn Philippe Christine D. Smart Jocelyn K. C. Rose Lawrence B. Smart 《Global Change Biology Bioenergy》2020,12(3):213-222
Hemp (Cannabis sativa L.) is an emerging dioecious crop grown primarily for grain, fiber, and cannabinoids. There is good evidence for medicinal benefits of the most abundant cannabinoid in hemp, cannabidiol (CBD). For CBD production, female plants producing CBD but not tetrahydrocannabinol (THC) are desired. We developed and validated high‐throughput PACE (PCR Allele Competitive Extension) assays for C. sativa plant sex and cannabinoid chemotype. The sex assay was validated across a wide range of germplasm and resolved male plants from female and monoecious plants. The cannabinoid chemotype assay revealed segregation in hemp populations, and resolved plants producing predominantly THC, predominantly CBD, and roughly equal amounts of THC and CBD. Cultivar populations that were thought to be stabilized for CBD production were found to be segregating phenotypically and genotypically. Many plants predominantly producing CBD accumulated more than the current US legal limit of 0.3% THC by dry weight. These assays and data provide potentially useful tools for breeding and early selection of hemp. 相似文献
107.
Rose Seth Cacho Frances Wiersma Lenny Magdaleno Anthony Anderson Nicholas Statler Traci 《Applied psychophysiology and biofeedback》2021,46(2):205-214
Applied Psychophysiology and Biofeedback - Biofeedback (BF) training has been utilized with performers for years. Previous literature highlights the effectiveness of multi-week intervention... 相似文献
108.
Gregory J. Buda William J. Barnes Eric A. Fich Sungjin Park Trevor H. Yeats Lingxia Zhao David S. Domozych Jocelyn K.C. Rose 《The Plant cell》2013,25(10):4000-4013
The plant cuticle is thought to be a critical evolutionary adaptation that allowed the first plants to colonize land, because of its key roles in regulating plant water status and providing protection from biotic and abiotic stresses. Much has been learned about cuticle composition and structure through genetic and biochemical studies of angiosperms, as well as underlying genetic pathways, but little is known about the cuticles of early diverging plant lineages. Here, we demonstrate that the moss Physcomitrella patens, an extant relative of the earliest terrestrial plants, has a cuticle that is analogous in both structure and chemical composition to those of angiosperms. To test whether the underlying cuticle biosynthetic pathways were also shared among distant plant lineages, we generated a genetic knockout of the moss ATP binding cassette subfamily G (ABCG) transporter Pp-ABCG7, a putative ortholog of Arabidopsis thaliana
ABCG transporters involved in cuticle precursor trafficking. We show that this mutant is severely deficient in cuticular wax accumulation and has a reduced tolerance of desiccation stress compared with the wild type. This work provides evidence that the cuticle was an adaptive feature present in the first terrestrial plants and that the genes involved in their formation have been functionally conserved for over 450 million years. 相似文献
109.
William B. Parker Sue C. Shaddix Lucy M. Rose Phuong T. Pham Mei Hua Robert Vince 《Nucleosides, nucleotides & nucleic acids》2013,32(4):795-804
Abstract The metabolism of O6-propyl-carbovir and N6-propyl-carbovir, two selective inhibitors of HIV replication, has been evaluated in CEM cells. Both compounds were phosphorylated in intact cells to carbovir-5′-triphosphate. The metabolism of these two agents was inhibited by deoxycoformycin and mycophenolic acid, but not erythro-9-(2-hydroxy-3-nonyl)adenine. No evidence of the 5′-triphosphate of either compound was detected in CEM cells. 相似文献
110.
The orphan receptor ROS1 is a human proto‐oncogene, mutations of which are found in an increasing number of cancers. Little is known about the role of ROS1, however in vertebrates it has been implicated in promoting differentiation programs in specialized epithelial tissues. In this study we show that the C. elegans ortholog of ROS1, the receptor tyrosine kinase ROL‐3, has an essential role in orchestrating the morphogenesis and development of specialized epidermal tissues, highlighting a potentially conserved function in coordinating crosstalk between developing epithelial cells. We also provide evidence of a direct relationship between ROL‐3, the mucin SRAP‐1, and BCC‐1, the homolog of mRNA regulating protein Bicaudal‐C. This study answers a longstanding question as to the developmental function of ROL‐3, identifies three new genes that are expressed and function in the developing epithelium of C. elegans, and introduces the nematode as a potentially powerful model system for investigating the increasingly important, yet poorly understood, human oncogene ROS1. genesis 51:545–561. © 2013 Wiley Periodicals, Inc. 相似文献