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991.
Xianfang Wu Viet Loan Dao Thi Yumin Huang Eva Billerbeck Debjani Saha Hans-Heinrich Hoffmann Yaomei Wang Luis A. Vale Silva Stephanie Sarbanes Tony Sun Linda Andrus Yingpu Yu Corrine Quirk Melody Li Margaret R. MacDonald William M. Schneider Xiuli An Brad R. Rosenberg Charles M. Rice 《Cell》2018,172(3):423-438.e25
992.
Cations‐induced DNA aggregation can modify the local structure of oligonucleotides and has potential applications in medicine and biotechnology. Here, we used atomic force microscopy to investigate λ‐DNA aggregation on Mg2+‐treated glass (Mg2+/glass) and in Mg2+ solution. Atomic force microscopy topography images showed that some DNA fragments were slightly stacked together on 10 mM Mg2+/glass and stacked stronger on ≥50 mM Mg2+/glass. They also showed that DNA aggregated stronger in Mg2+ solution than on Mg2+/glass, ie, DNAs are strongly stacked and twisted at 10 mM Mg2+, rolled together at 50 mM Mg2+, and slightly aggregated to form small particles at 100 mM Mg2+. At a specific condition, ie, heating λ‐DNA to 92°C, cooling down to 75°C, adding Mg2+, and vortexing the resulting solution, DNA strongly aggregated and formed pancake‐like shapes at 10 and 50 mM or a large aggregate at 100 mM Mg2+ solutions. Our results may be helpful for medical applications and gene therapy using cation‐DNA technology. 相似文献
993.
Quynh-Mai Thi Ngo Thao Quyen Cao Phi-Long Tran Jeong Ah Kim Sang-Tae Seo Jin-Cheol Kim Mi Hee Woo Jeong Hyung Lee Byung Sun Min 《Bioorganic & medicinal chemistry letters》2018,28(11):2109-2115
Five new lactones, litsenolide F1 (1), lisealactone H1 (10), lisealactone H2 (11), akolactone D (13), and akolactone E (14), along with thirteen known compounds were isolated from the pericarps of Litsea japonica (Thunb.) Jussieu. Their chemical structures were elucidated by extensive spectroscopic analyses, including 1D and 2D NMR, HRMS, and chemical methods. The isolated compounds were evaluated for their inhibitory effects on NO production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Among them, 2-alkylidene-3-hydroxy-4-methylbutanolide derivatives (compounds 1–9) exhibited the most potent activity, with IC50 values in the range of 2.9–12.8?μM. In additon, compounds 1, 3, 4, and 6 showed inhibition of iNOS and COX-2 expression in concentration-dependent manner. Compound 3 suppresses mRNA expression of iNOS, COX-2, IL-6, and TNF-α in LPS-stimulated RAW264.7 cells. Based on these evidence, the isolated lactones from L. japonica could be promissing candidates for the development of new anti-inflammatory agents. 相似文献
994.
Physiological role of urothelial cancer‐associated one long noncoding RNA in human skeletogenic cell differentiation 下载免费PDF全文
995.
Nguyen Anh Tuan Bui Hong Quang Nguyen Quang Hung Akihiko Sasamoto 《Nordic Journal of Botany》2018,36(3)
A new species, Asarum yentuense N. Tuan & Sasamoto (Aristolochiaceae), is described from Quang Ninh Province, Vietnam. This species belongs to A. subgen. Heterotropa sect. Longistylis and is most similar to Asarum petelotii, A. glabrum, A. reticulatum and A. magnificum var. dinghuense, but is differentiated by morphology, including the length of the calyx tube and lobes, and phenology. 相似文献
996.
New taxa and taxonomic notes in Aspidistra (Convallariaceae s.s.) in China,Laos and Vietnam 下载免费PDF全文
997.
Huong Thi Mai Nguyen Gilles Billen Josette Garnier Thi Phuong Quynh Le Quoc Long Pham Sylvain Huon Emma Rochelle-Newall 《Biogeochemistry》2018,138(3):277-295
The Red River, draining a 169,000 km2 watershed, is the second largest river in Viet Nam and constitutes the main source of water for a large percentage of the population of North Viet Nam. Here we present the results of an investigation into the spatial distribution and temporal dynamics of particulate and dissolved organic carbon (POC and DOC, respectively) in the Red River Basin. POC concentrations ranged from 0.24 to 5.80 mg C L?1 and DOC concentrations ranged from 0.26 to 5.39 mg C L?1. The application of the Seneque/Riverstrahler model to monthly POC and DOC measurements showed that, in general, the model simulations of the temporal variations and spatial distribution of organic carbon (OC) concentration followed the observed trends. They also show the impact of high population densities (up to 994 inhab km?2 in the delta area) on OC inputs in surface runoff from the different land use classes and from urban point sources. A budget of the main fluxes of OC in the whole river network, including diffuse inputs from soil leaching and runoff and point sources from urban centers, as well as algal net primary production and heterotrophic respiration was established using the model results. It shows the predominantly heterotrophic character of the river system and provides an estimate of CO2 emissions from the river of 330 Gg C year?1. This value is in reasonable agreement with the few available direct measurements of CO2 fluxes in the downstream part of the river network. 相似文献
998.
Franz Thiébaut Jon B. Reitan Kari Feren Jean Paul Rigaut Albrecht Reith 《Cell and tissue research》1986,246(1):1-6
Summary The simultaneous use of a silver-staining technique, backscattered electron imaging and stereo-tilts has made it possible to visualize the spatial distribution of cell nuclei in the stretched epithelium of the bladder of mice. This study has led to the observation that a structural organization resembling the epidermal proliferative unit, previously found in the skin exists also in bladder epithelium. However, the proliferative unit in the bladder was different in that it contained a higher number of cells per unit, and an absence of columns of inactive squamous cells. These findings may indicate that epidermal proliferative unit-like structures represent a common form of organization in some epithelia. 相似文献
999.
S Dufour J L Duband J P Thiéry 《Biology of the cell / under the auspices of the European Cell Biology Organization》1986,58(1):1-13
Fibronectins are multifunctional glycoproteins involved in the embryogenesis and in multiple physiological processes. Most of their functions derive from interactions of these glycoproteins with the cell surface. Fibronectin and their cell surface receptor constitute the major cell-substratum adhesion that plays a key role in cell adhesion, cell spreading and cell motility, particularly during embryonic development. Additionally, other functions of fibronectins are due to their ability to ban a great variety of macromolecules contained in an extracellular matrix and in plasma. In particular, the interaction of fibronectins with the cell surface, collagen, fibrin and fibrinogen are involved in physiological processes such as hemostasis, wound healing and phagocytosis. 相似文献
1000.
Interactions between inhibin, oestradiol and progesterone in the control of gonadotrophin secretion in the ewe 总被引:2,自引:0,他引:2
Experiments were carried out to test the hypothesis that inhibin and oestradiol act synergistically to inhibit the secretion of FSH, to test for effects of progesterone, and to compare the FSH and LH responses to ovarian feedback. In Exp. 1, with 11 ovariectomized and 12 intact Romanov ewes during the anoestrous season, doses of oestradiol (administered by means of subcutaneous implants) that restored normal LH pulse frequencies were insufficient to restore normal concentrations of FSH. In Exp. 2, with 48 ovariectomized Welsh Mountain ewes during the breeding season, a factorial design with 4 ewes per cell was used to assess the responses in LH and FSH to 3 doses of oestradiol (s.c. implants) and 4 doses of bovine follicular fluid ('inhibin', 0.2-1.6 ml s.c. every 8 h). This was done initially in the absence of progesterone and then after 7 days of treatment with progesterone (s.c. implants). Analysis of variance revealed a significant synergistic interaction between oestradiol and inhibin on the plasma concentrations of FSH. Progesterone had little effect. In contrast, there was a significant synergistic interaction between oestradiol and progesterone on the concentrations of LH. 'Inhibin' also inhibited LH secretion but this effect was independent of the two steroids. We conclude that there are basic differences in the way that ovarian feedback acts to control the secretion of LH and FSH in the ewe. FSH secretion appears to be primarily controlled by the synergistic action of oestradiol and inhibin on the anterior pituitary gland, while the secretion of LH is inhibited during the follicular phase by an effect of oestrogen at pituitary level and during the luteal phase by the synergistic action of oestradiol and progesterone at the hypothalamic level. Inhibin, or another non-steroidal factor in follicular fluid, may also play a minor role in the control of LH secretion. 相似文献