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61.
The relative influence of in situ and neighborhood factors on reptile recolonization in post‐mining restoration sites 下载免费PDF全文
Maggie D. Triska Michael D. Craig Vicki L. Stokes Roger P. Pech Richard J. Hobbs 《Restoration Ecology》2016,24(4):517-527
Restoration can be important in slowing, or reducing, rates of biodiversity loss, but needs to consider the factors influencing fauna recolonization as part of the recovery process. Although many studies of factors influencing faunal recolonization have examined the influence of in situ site factors, fewer have examined the influence of neighborhood landscape factors, especially in landscapes with permeable matrices. To assess the relative influence of landscape and site factors on reptile recolonization in a production landscape with a permeable matrix, we surveyed reptiles at intact reference sites and post‐mining restoration sites (3–20 years post‐mining [YPM]) in a forest ecosystem in southwestern Australia. Reptile assemblages in restoration sites never converged on those in reference habitat. Reptile species composition and individual species abundances (>20 detections) in restoration sites were primarily influenced by site factors such as canopy height, litter cover, and coarse woody debris volume, and not by landscape factors. We suggest that the most common reptile species in our study area are primarily influenced by site factors, not landscape factors, and most reptiles detected in restoration sites were present by 3–4 YPM. Therefore, it is likely that habitat suitability is the main barrier to most species' recolonization of restoration sites in landscapes with permeable matrices. Management should continue to focus on restoring microhabitats and vegetation structure, which is similar to reference habitat to promote recolonization of restoration sites by reptiles. 相似文献
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Summary
B. subtilis strains carrying plasmids pBDA 318, pUBA 10, pUBA 11 and pUBA 20 were cultivated for up to 50 generations without antibiotic selection and then screened for the presence of the plasmid and -amylase gene. The plasmid pUBA 11 proved stable for industrial production, the other plasmids showed structural and segregational instability. 相似文献
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Gladis Magnarelli María S. Souza Ana M. Pechén de D'Angelo 《Journal of biochemical and molecular toxicology》2009,23(3):185-192
Organochlorine pesticides have been detected in placenta. The ability of heptachlor (HC) and 1,1,1‐tricholoro‐2‐(2‐chlorophenyl)‐2‐4‐chlorophenyl)ethane (o‐p′DDT) to interfere with protein phosphorylation was evaluated. In vitro incubations of cell‐free placental villi homogenates with a concentration range 1–100 µM were performed. In particulate fractions, total serine/threonine kinase activity was increased by 10 µM HC and o‐p′ DDT (59% and 82%, respectively). Maximum eightfold increase was observed with 10 µM o‐p′ DDT on protein kinase A activity. By contrast, protein kinase C activity was reduced by 10 µM HC and o‐p′ DDT (40% and 52%, respectively). Endogenous substrate phosphorylation studies demonstrated that slight but significant increase in 24‐kDa band labeling was produced in nuclear samples with 1, 10, and 100 µM HC and 100 µM o‐p′ DDT. Exposition to 100 µM HC increased 85‐kDa band labeling. In mitochondrial fractions, 10 µM HC and o‐p′ DDT increased 24‐ and 65‐kDa bands' labeling. These data indicate that both pesticides affect protein kinase activities in particulate fraction. Nuclear compartmentalization of these compounds, insertion in membranes, and chemical stress production may be associated to the observed effects, thus suggesting deleterious consequences in signaling pathways. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:185–192, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20277 相似文献
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Ferrari A Venturino A Pechén de D'Angelo AM 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,146(3):308-313
The organophosphate azinphos methyl (AzMe) and the carbamate carbaryl are the insecticides mostly used in the irrigated valley of Río Negro and Neuquén, Patagonia, Argentina. Juvenile rainbow trout were exposed to AzMe and carbaryl and the sensitivity of skeletal muscular cholinesterase (ChE) and the time course of inhibition and recovery were evaluated. EC50 values demonstrated that AzMe was a stronger in vivo inhibitor of muscular ChE (1.05+/-0.23 microg/L) than carbaryl (270+/-62.23 microg/L). Muscular ChE was significantly less sensitive to both insecticides than brain ChE. EC50 values obtained for muscular ChE were closer than those for brain ChE to the respective pesticide lethal concentrations, pointing out the relevance of the muscular enzyme in determining acute toxicity. The recovery process of ChE activity after carbaryl exposure (500 microg/L) was fast, whereas no significant recovery was observed with AzMe (1 microg/L) after 21 days in uncontaminated media. Brain and muscular ChE were inhibited and showed a significant but not complete recovery after three consecutive 48-h exposures to AzMe (1 microg/L) followed by a recovery period of 7 days. This scheme mimics the periodical application of the insecticides in the region and suggests a certain probability of a sustained ChE inhibition under field conditions, affecting fish development and survival. 相似文献
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C Allard V Desgagné J Patenaude M Lacroix L Guillemette MC Battista M Doyon J Ménard JL Ardilouze P Perron L Bouchard MF Hivert 《Epigenetics》2015,10(4):342-351
Leptin is an adipokine that acts in the central nervous system and regulates energy balance. Animal models and human observational studies have suggested that leptin surge in the perinatal period has a critical role in programming long-term risk of obesity. In utero exposure to maternal hyperglycemia has been associated with increased risk of obesity later in life. Epigenetic mechanisms are suspected to be involved in fetal programming of long term metabolic diseases. We investigated whether DNA methylation levels near LEP locus mediate the relation between maternal glycemia and neonatal leptin levels using the 2-step epigenetic Mendelian randomization approach. We used data and samples from up to 485 mother-child dyads from Gen3G, a large prospective population-based cohort. First, we built a genetic risk score to capture maternal glycemia based on 10 known glycemic genetic variants (GRS10) and showed it was an adequate instrumental variable (β = 0.046 mmol/L of maternal fasting glucose per additional risk allele; SE = 0.007; P = 7.8 × 10−11; N = 467). A higher GRS10 was associated with lower methylation levels at cg12083122 located near LEP (β = −0.072 unit per additional risk allele; SE = 0.04; P = 0.05; N = 166). Direction and effect size of association between the instrumental variable GRS10 and methylation at cg12083122 were consistent with the negative association we observed using measured maternal glycemia. Lower DNA methylation levels at cg12083122 were associated with higher cord blood leptin levels (β = −0.17 log of cord blood leptin per unit; SE = 0.07; P = 0.01; N = 170). Our study supports that maternal glycemia is part of causal pathways influencing offspring leptin epigenetic regulation. 相似文献
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Ingrid Žitňanová Silvia Ranostajová Hana Sobotová Denisa Demelová Ivan Pecháň Zdeňka Ďuračková 《Biologia》2006,61(3):279-284
Recent studies have demonstrated that dietary plants are rich source of antioxidants and can contribute to the protection
from age-related diseases. The aim of our study was to determine the total antioxidant capacity of extracts from different
kinds of fruits and vegetables, and to examine their inhibitory effect on the oxidative damage to proteins in vitro. For determination of antioxidant capacity we used two direct methods. Among the food materials chosen for the present study,
blueberries and red beets gave the maximum antioxidant activity. The lowest activity was determined in pears and green beans.
Some extracts were more active in one method, while their activity was lower using the other method. To investigate inhibitory
effects of fruits and vegetables extracts on the oxidative damage to proteins in vitro, we induced the oxidative damage to plasma proteins by sodium hypochlorite leading to formation of carbonyl compounds detected
by spectrophotometric method. All extracts of fruits and vegetables showed inhibitory activity on the oxidative damage to
proteins with raspberries and leek as most effective. Results of this study will be useful as an aid for dietary choices to
increase antioxidant intake and will allow the investigation of the relation between dietary antioxidants and oxidative stress-induced
diseases. 相似文献
70.
EM Tazi I Lalya MF Tazi Y Ahellal H M'rabti H Errihani 《World journal of surgical oncology》2010,8(1):1-3
Goblet cell carcinoid of the large intestine is a rare neoplasm, usually located in ascending colon and rectum. A 60-year-old male patient underwent surgery after the diagnosis of acute abdomen. Exploratory laparotomy revealed perforation with a diameter of 1 cm at the site of the previously performed gastroenterostomy and dilatation of the right colic flexure, secondary to a solid obstructive mass located in the mid-portion of transverse colon. Histopathological investigation of the biopsies, taken from the gastroenterostomy site and the tumor, revealed mixed carcinoid-adenocarcinoma with carcinoid component, predominantly composed of goblet cells. Three cycles of FOLFOX-4 protocol was administered. Following respiratory distress secondary to pulmonary metastasis, the patient's condition deteriorated and subsequently died in the fourth postoperative month. Our aim with this paper is to point out that more cases should be reported for more effective diagnosis, histopathological study, clinical investigation, treatment and prognosis of this specific neoplasm. 相似文献