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81.
Since its invasion of North America in 2000, the soybean aphid, Aphis glycines Matsumura (Homoptera: Aphididae) has notably changed the arthropod community of the soybean agroecosystem. The objectives
of this study were to characterize the foliar predatory fauna associated with A. glycines in commercial soybean fields in Québec, Canada, and to evaluate the suitability of A. glycines as prey for three coccinellid species: Harmonia axyridis Pallas, Propylea quatuordecimpunctata L. and Coleomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae). Field surveys showed that several predators responded rapidly to expanding and increasing
populations of the soybean aphid. Coccinellidae were the most important aphidophagous predators observed in 2002 (58.6%) and
2003 (44.8%), with mainly four native and naturalized species co-occurring with the soybean aphid throughout the growing season.
Measurement of fitness parameters under laboratory conditions (survival, development time, longevity, fecundity) indicated
that A. glycines is an excellent prey for the development and reproduction of all three of the coccinellid species studied. The intrinsic
rate of natural increase (rm) was highest for H. axyridis (0.238 d−1), intermediate for P. quatuordecimpunctata (0.215 d−1) and lowest for C. maculata (0.134 d−1). 相似文献
82.
Catherine Fabre Assou El Battari Catherine Bellan Eric Pasqualini Jacques Marvaldi Dominique Lombardo Jos Luis 《Peptides》1993,14(6):1331-1338
The human pancreatic cell line BxPC-3 displays two classes of binding sites with high and low affinity for VIP. The order of potency of VIP-related peptides in inhibiting either [125I]VIP or [125I]N-AcPACAP27 binding and in stimulating cAMP production was typical of the human VIP receptor. By combining affinity labeling with glycosidase treatments, we have characterized the VIP receptor as a Mr = 68,200 glycoprotein, consisting of a Mr = 39,300 polypeptide core with at least three N-linked oligosaccharide chains. In addition, our results revealed the presence of a low amount of sialic acid residues in the carbohydrate moiety of receptor. 相似文献
83.
Caberg JH Hubert P Herman L Herfs M Roncarati P Boniver J Delvenne P 《Cancer immunology, immunotherapy : CII》2009,58(1):39-47
Human papillomavirus (HPV) infection, particularly type 16, is causally associated with cancer of the uterine cervix. The
persistence or progression of cervical lesions suggests that viral antigens are not adequately presented to the immune system.
This hypothesis is reinforced by the observation that most squamous intraepithelial lesions (SILs) show quantitative and functional
alterations of Langerhans cells (LC). The infiltration of immature LC in the squamous epithelium is mainly controlled by Macrophage
Inflammatory Protein 3α/CCL20. After having shown that CCL20 production is altered in HPV-transformed keratinocytes (KC),
the possible role of HPV16 E6 and E7 viral oncoproteins in the reduced CCL20 levels observed in SILs was investigated by silencing
HPV16 E6 and E7 oncogenes by RNA interference (siRNA). This treatment not only increased CCL20 secretion but also resulted
in the modulation of NF-κB p50, p52 and p65 precursor localization. Moreover, silencing of E6 and E7 oncogenes in HPV16-transformed
KC induced a significantly higher migratory capacity of LC in a Boyden chamber assay and in an in vitro formed (pre)neoplastic
epithelium reminiscent of high-grade SILs. Anti-CCL20 neutralizing antibody experiments showed that the increased migration
of LC is due to the re-expression of CCL20 in E6 and E7 siRNA transfected KC. These data suggest that HPV16 E6/E7-induced
down-regulation of CCL20 observed during the cervical carcinogenesis may contribute to a diminished capacity of the immune
system to control HPV infection.
P. Hubert and J. H. Caberg contributed equally to this work. 相似文献
84.
Lou Yuting Kawaue Takumi Yow Ivan Toyama Yusuke Prost Jacques Hiraiwa Tetsuya 《Biomechanics and modeling in mechanobiology》2022,21(5):1511-1530
Biomechanics and Modeling in Mechanobiology - Tissue layers can generally slide at the interface, accompanied by the dissipation due to friction. Nevertheless, it remains elusive how force could... 相似文献
85.
Lutringer-Magnin D Girard N Cadranel J Leroux C Quoix E Cottin V Del Signore C Lebitasy MP Cordier G Vanhems P Mornex JF 《PloS one》2012,7(5):e37889
Pneumonic-type lung adenocarcinoma (P-ADC) represents a distinct subset of lung cancer with specific clinical, radiological, and pathological features. Given the weak association with tobacco-smoking and the striking similarities with jaagsiekte sheep retrovirus (JSRV)-induced ovine pulmonary adenocarcinoma, it has been suggested that a zoonotic viral agent infecting pulmonary cells may predispose to P-ADC in humans. Our objective was to explore whether exposure to domestic small ruminants may represent a risk factor for P-ADC. We performed a multicenter case-control study recruiting patients with P-ADC as cases and patients with non-P-ADC non-small cell lung cancer as controls. A dedicated 356-item questionnaire was built to evaluate exposure to livestock. A total of 44 cases and 132 controls were included. At multivariate analysis, P-ADC was significantly more associated with female gender (Odds-ratio (OR)?=?3.23, 95% confidence interval (CI): 1.32-7.87, p?=?0.010), never-smoker status (OR?=?3.57, 95% CI: 1.27-10.00, p?=?0.015), personal history of extra-thoracic cancer before P-ADC diagnosis (OR?=?3.43, 95% CI: 1.10-10.72, p?=?0.034), and professional exposure to goats (OR?=?5.09, 95% CI: 1.05-24.69, p?=?0.043), as compared to other subtypes of lung cancer. This case-control suggests a link between professional exposure to goats and P-ADC, and prompts for further epidemiological evaluation of potential environmental risk factors for P-ADC. 相似文献
86.
David Nanchen Nicolas Rodondi Jacques Cornuz Teresa Hillier Kristine E. Ensrud Jane A. Cauley Douglas C. Bauer Study of Osteoporotic Fractures Research Group 《PloS one》2012,7(11)
Background
Current guidelines for the prevention of cardiovascular disease (CVD) recommend diabetes as a CVD risk equivalent. However, reports that have examined the risk of diabetes in comparison to pre-existing CVD are lacking among older women. We aimed to assess whether diabetes was associated with a similar risk of total and cause-specific mortality as a history of CVD in older women.Methodology/Principal Findings
We studied 9218 women aged 68 years or older enrolled in a prospective cohort study (Study of Osteoporotic Fracture) during a mean follow-up period of 11.7 years and compared all-cause, cardiovascular and coronary heart disease mortality among 4 groups: non-diabetic women with and without existing CVD, diabetic women with and without existing CVD. Mean (SD) age of the participants was 75.2 (5.3) years, 3.5% reported diabetes and 6.8% reported existing CVD. During follow-up, 5117 women died with 36% from CVD. The multivariate adjusted risk of cardiovascular mortality was increased among both non-diabetic women with CVD (hazard ratio (HR) 2.32, 95% CI: 1.97–2.74, P<0.001) and diabetic women without CVD (HR 2.06, CI: 1.62–2.64, P<0.001) compared to non-diabetic women without existing CVD. All-cause, cardiovascular and coronary mortality of non-diabetic women with CVD were not significantly different from diabetic women without CVD.Conclusions/Significance
Older diabetic women without CVD have a similar risk of cardiovascular mortality compared to non-diabetic women with pre-existing CVD. The equivalence of diabetes and CVD seems to extend to older women, supporting current guidelines for cardiovascular prevention. 相似文献87.
Changes in Human Immunodeficiency Virus Type 1 Populations after Treatment Interruption in Patients Failing Antiretroviral Therapy 总被引:7,自引:0,他引:7 下载免费PDF全文
88.
Analysis of phytochrome- and ABA-deficient mutants suggests that ABA degradation is controlled by light in Nicotiana plumbaginifolia 总被引:4,自引:2,他引:4
Yvan Kraepiel Philippe Rousselin Bruno Sotta Lucien Kerhoas Jacques Einhorn Michel Caboche Emile Miginiac 《The Plant journal : for cell and molecular biology》1994,6(5):665-672
The phytochrome chromophore-deficient mutant, pew1, of Nicotiana plumbaginifolia exhibited decreased germination and slower dehydration of detached leaves during water stress as compared with the wild-type. These physiological processes are controlled by abscisic acid (ABA) and we examined, therefore, whether phytochrome plays a specific role in the regulation of ABA metabolism using the pew1 mutant. The ABA contents of mature seeds and young leaves were analysed and in both cases mutant material was found to contain higher amounts of ABA as compared with the wild-type. This indicates that the phytochrome activation can lead to a decrease of the ABA level in the wild-type plant. The role of phytochromes was investigated in greater detail using the ABA-deficient mutant aba1 of N. plumbaginifolia exhibiting an early and synchronous germination. This mutant accumulates at very high levels a metabolite derived from a precursor (ABA-aldehyde) in the ABA biosynthetic pathway. The first biochemical characterization of this molecule, which corresponds to the glucose-conjugated ABA-alcohol (ABA-AG) is described. A pew1-aba1 double mutant exhibiting both an etiolated growth and early germination was also obtained. The comparable accumulation of ABA-AG in the pew1-aba1 double mutant as compared with the aba1 mutant allowed the proposition that, in a wild-type plant, the phytochrome-mediated light signal enhances ABA degradation rather than inhibits its biosynthesis. 相似文献
89.
90.
Sarah E. McClain Heath M. Hagy Christopher S. Hine Aaron P. Yetter Christopher N. Jacques John W. Simpson 《Restoration Ecology》2019,27(1):168-177
Modifications of the Illinois River and associated tributaries have resulted in altered hydrologic cycles and persistent river‐floodplain connections during the growing season that frequently impede the establishment of hydrophytic vegetation and have reduced value for migratory waterfowl and other waterbirds. To help guide floodplain restoration, we compared energetic carrying capacity for waterfowl in two wetland complexes along the Illinois River under different management regimes during 2012–2015. The south pool of Chautauqua National Wildlife Refuge (CNWR) was seasonally flooded due to a partial river connection and managed for moist‐soil vegetation. Emiquon Preserve was hydrologically isolated from the Illinois River by a high‐elevation levee and managed as a semipermanently flooded emergent marsh. Semipermanent emergent marsh management at Emiquon Preserve produced 5,495 energetic use‐days (EUD)/ha for waterfowl and other waterbirds across wetland cover types and years, and seasonal moist‐soil management at CNWR produced 6,199 EUD/ha in one of 4 years. At Emiquon Preserve, the aquatic bed cover type produced 9,660 EUD/ha, followed by 5,261 EUD/ha in moist‐soil, 1,398 EUD/ha in persistent emergent, 1,185 EUD/ha in hemi‐marsh, and 12 EUD/ha in open water cover types. At CNWR, the annual grass and sedge cover type produced 7,031 EUD/ha, followed by 5,618 EUD/ha in annual broadleaf and 1,305 EUD/ha in perennial grass cover types. Restoration of floodplain wetlands in isolation from frequent flood pulses during the growing season can produce hemi‐marsh and aquatic bed vegetation communities that provide high‐quality habitat for waterfowl and which have been mostly eliminated from large river systems in the Midwest, U.S.A. 相似文献