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111.
U Raab P Lastres M A Arévalo J M López-Novoa C Caba?as E J de la Rosa C Bernabéu 《FEBS letters》1999,459(2):249-254
Endoglin is a component of the transforming growth factor beta (TGF-beta) receptor complex, highly expressed by endothelial cells. Mutations in the endoglin gene are responsible for hereditary hemorrhagic telangiectasia type 1 (HHT1), an autosomal dominant vascular disorder caused by a haploinsufficiency mechanism. Vascular lesions (telangiectasia and arteriovenous malformations) in HHT1 are associated with loss of the capillary network, suggesting the involvement of endoglin in vascular repair processes. Using the chick chorioallantoic membrane (CAM) as an angiogenic model, we have analyzed the expression and function of chicken endoglin. A pan-specific polyclonal antibody (pAb) recognized chicken endoglin as demonstrated by immunostaining and Western blot analysis. In ovo treatment of chicken embryos with this pAb resulted in a significantly increased area of CAM. This effect was likely mediated by modulation of the ligand binding to endoglin as this pAb was able to inhibit TGF-beta1 binding. These results support the involvement of endoglin in the angiogenic process. 相似文献
112.
Phytoplankton biomass and productivity were measured during two cruises in the Bransfield Strait in December 1991 (D91) and
January/February 1993 (J93). Strong seasonal variability in productivity values was observed due to differences in the physiological
response of phytoplankton. However, although the photosynthetic capacity of phytoplankton was markedly lower in D91 [P
m
B
=0.61 ± 0.25 mg C (mg Chla)−1 h−1] than in J93 [P
m
B
=2.18 ± 0.91 mg C (mg Chla)−1 h−1], average water column chlorophyll values in different areas of the strait were approximately similar in D91 (49–78 mg Chla
m−2) and J93 (22–76 mg Chla m−2). The spatial distribution of chlorophyll was patchy and generally associated with the influence of the different water masses
that meet together in the Bransfield Strait. No correlation was found between the mixed layer depth and either the integrated
chlorophyll or the productivity. Our results suggest that major phytoplankton blooms in the Bransfield Strait are advected
from the nearby Gerlache Strait or Bellingshausen Sea following the main eastward surface currents.
Accepted: 5 July 1998 相似文献
113.
114.
Namazi M Karbasi-Afshar R Safi M Serati A 《Indian pacing and electrophysiology journal》2008,8(2):133-136
We report a 48 year old male who presented with diaphragmatic stimulation. The biventricular implantable cardioverter and defibrillator (CRT-D) was implanted two weeks before admission and active fixation lead caused perforation of the right atrial wall. Echocardiography did not demonstrate pericardial effusion but Chest X-ray and computed tomography (CT) visualized the atrial screw helix outside the right atrial wall, penetrating through the right lung middle lobe. There was no atrial capture. After changing the pace mode DDDR to VVIR, diaphragmatic stimulation was disappeared. The atrial lead was repositioned and fixed again. During the hospital admission and after that the patient was well and free of any symptoms. 相似文献
115.
Multiple models for Rosaceae genomics 总被引:5,自引:0,他引:5
Shulaev V Korban SS Sosinski B Abbott AG Aldwinckle HS Folta KM Iezzoni A Main D Arús P Dandekar AM Lewers K Brown SK Davis TM Gardiner SE Potter D Veilleux RE 《Plant physiology》2008,147(3):985-1003
The plant family Rosaceae consists of over 100 genera and 3,000 species that include many important fruit, nut, ornamental, and wood crops. Members of this family provide high-value nutritional foods and contribute desirable aesthetic and industrial products. Most rosaceous crops have been enhanced by human intervention through sexual hybridization, asexual propagation, and genetic improvement since ancient times, 4,000 to 5,000 B.C. Modern breeding programs have contributed to the selection and release of numerous cultivars having significant economic impact on the U.S. and world markets. In recent years, the Rosaceae community, both in the United States and internationally, has benefited from newfound organization and collaboration that have hastened progress in developing genetic and genomic resources for representative crops such as apple (Malus spp.), peach (Prunus spp.), and strawberry (Fragaria spp.). These resources, including expressed sequence tags, bacterial artificial chromosome libraries, physical and genetic maps, and molecular markers, combined with genetic transformation protocols and bioinformatics tools, have rendered various rosaceous crops highly amenable to comparative and functional genomics studies. This report serves as a synopsis of the resources and initiatives of the Rosaceae community, recent developments in Rosaceae genomics, and plans to apply newly accumulated knowledge and resources toward breeding and crop improvement. 相似文献
116.
Spatial patterns of trees and juveniles in a laurel forest of Tenerife, Canary Islands 总被引:5,自引:0,他引:5
Spatial patterns are important characteristics of the forest and theycan reveal such things as successional status and ecological characteristics ofthe species. We tested the hypothesis that spatial distribution will bedifferent, depending on whether the species is intolerant or tolerant to shade.We assessed the spatial distribution of trees (> 4 cm dbh) andjuveniles in eight laurel forest plots. A univariate spatial analysis(performed with Ripley's K1) showed that all tree species havesignificantaggregation at short distances (2 m). Nevertheless, two groups ofspecies could be differentiated: Erica scoparia,Myrica faya and Ilex canariensisshowed a tendency for aggregation at large distances (larger than 6m)while L. azorica and Prunuslusitanicashowed aggregation only at shorter distances. Ripley's BivariateK1,2 analyses showed no significant differences in the spatialdistribution ofanalyzed species pairs from a null model. Only Laurusazoricahad a sufficient sample size for analysis of juvenile distribution. Aunivariateanalysis revealed thatL. azorica seedlings (stems < 50 cm high)were clumped in some plots up to 5 m, but this was not consistent.Saplings (stems > 50 cm high and < 4 cm dbh)didnot show strong clumping even at short distances. L.azoricasaplings had no significant aggregation with, nor repulsionfrom, adults of the same or different species. Spatial patterns of the speciesshould be considered in the development of restoration plans of the laurelforest 90%of which has disappeared or been intensively disturbed on Tenerife Island. 相似文献
117.
Eloisa Berman Arévalo Mirjam A. F. Ros-Tonen 《Human ecology: an interdisciplinary journal》2009,37(6):733-747
While much research on forest partnerships hitherto has been focused mainly on the drivers behind their formation, the kind
of actors and deals involved, and the factors that promote or hinder their success, much less attention has been paid to the
dynamic relationships and processes inherent in these partnerships. Based on the study of a partnership process in an indigenous
reservation in Colombian Amazonia covering a variety of projects, this paper seeks to fill part of this lacuna by analyzing
the partnership as a dynamic ‘discursive battlefield,’ in which objectives and actions are being constantly negotiated. Actors
in the Matavén partnership strategically incorporate discursive elements in order to pursue their own interests while also
endorsing those that ensure the continuation of collaboration. We conclude that discourses are embedded in partnership micro-politics.
On the one hand, discursive shifts occur as a reflection of power balances at given moments. On the other hand, discourses
constitute indispensable resources with the potential to both enhance individual actor’s negotiating power and to create opportunities
for compromise. Within an ongoing discursive tension between ‘conservation’ and ‘indigenous autonomy,’ flexible notions such
as ‘territorial ordering’ prove to be successful in allowing space for manoeuvre and granting conceptual coherence to shifts
occurring ‘on the ground.’ 相似文献
118.
Savvas Genitsaris Konstantinos Ar. Kormas & Maria Moustaka-Gouni 《FEMS microbiology ecology》2009,69(1):75-83
The morphological and phylogenetic diversity of the microscopic eukaryotes of the Lake Koronia water column was investigated during a mass kill of birds and fish in August–September 2004. The dominant morphospecies corresponded to the known toxin-producing species Prymnesium parvum , followed by Amoebidium sp., a taxon belonging to the group of parasitic Mesomycetozoea , and the common chlorophyte Pediastrum boryanum. Prymnesium exhibited heteromorphic life-cycle stages (flagellate and nonmotile coccoid cells). Phylogenetic analysis with 18S rRNA gene suggested that these heteromorphic stages belonged to the Platychrysis – Prymnesium monophyletic group. The most abundant phylotype was almost identical to P. boryanum . The fungal phylotypes were related to the Chytridiomycota , and the ciliate-like ones were closely related to Enchelys polynucleata and Pattersoniella vitiphila . Two phylotypes representing novel members belonging to the Jakobida and the Apicomplexa were also found. The microscopic eukaryotes of Lake Koronia include several organisms that are related to parasitic life modes. 相似文献
119.
Raul Zamora-Ros Mireia Urpí-Sardà Rosa M. Lamuela-Raventós Ramon Estruch Miguel Ángel Martínez-González Mònica Bulló Fernando Arós Antonio Cherubini Cristina Andres-Lacueva 《Free radical biology & medicine》2009,46(12):1562-1566
Several clinical and epidemiological studies have shown that moderate wine consumption may exert a protective effect against oxidative stress involved in several diseases, such as cardiovascular and neurodegenerative disorders. However, the epidemiological assessment of wine consumption has usually been obtained using self-reported questionnaires containing less reliable information for assessing total intake than nutritional biomarkers. A reliable biomarker for wine consumption is, therefore, needed. To validate urinary resveratrol metabolites (RMs) as a biomarker of wine consumption in a large cohort of free-living subjects, 1000 consecutive subjects entering a substudy of the PREDIMED trial (Prevención con Dieta Mediterránea) were evaluated. Data were collected in a validated semiquantitative food frequency questionnaire. RMs were measured in morning urine by LC-MS/MS. Urinary RM values correlated directly with reported daily amounts of wine consumed (r = 0.895; p < 0.001). One drink of wine per week can be detected. Using a cut-off of 411.4 nmol/g creatinine, the measurement of urinary RMs could discriminate wine consumers from non-wine consumers with a sensitivity of 93.3% (95% confidence interval (CI) 91.5–94.7%) and a specificity of 92.1% (CI 90.2–93.7%). Urinary RMs fulfill the criteria to be considered as a nutritional biomarker of wine consumption in a large sample of free-living subjects. This biomarker would provide an additional tool for investigating more precisely the relationship between wine consumption and health benefits. 相似文献
120.