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981.
982.
983.
《Molecular & cellular proteomics : MCP》2020,19(7):1132-1144
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- •Proteomes measured from human heart biopsies collected in-vivo covers >7000 cardiac proteins and highlight hundreds of chamber-specific molecular signatures that meaningfully reflect the specialized functions of the respective chambers.
- •Protein quantification from freshly collected biopsies is preferential to necropsy samples because of unspecific post-mortem protein degradation in the latter.
- •Increased abundances of proteins associated with sustained atrial fibrillation are not a sufficient condition to generate the disease state.
- •Protein abundance differences between atria and ventricle primarily originate at the level of gene regulation and reflect a functional need.
984.
985.
Hughes Colin R.; Queller David C.; Strassmann Joan E.; Davis Scott K. 《Behavioral ecology》1993,4(2):128-137
Genetic relatedness is expected to play a crucial role in theevolution of altruistic behaviors such as worker behavior inthe social insects. If individuals sacrifice their own reproduction,then the genes for this sacrifice will be lost unless theseindividuals aid the reproduction of others who share the genes.This leads to the prediction that altruism should be most commonin species with high relatedness among potential beneficiaries.Here we report an attempt to test for such an association. Weestimated both the incidence of altruism and the relatednessto potential beneficiaries in foundresses of seven species ofpaper wasps. The predicted positive correlation was not found,and we conclude that factors other than relatedness are moreimportant in determining interspecific differences in the incidenceof altruism. 相似文献
986.
Host preference and offspring performance are linked in three congeneric hyperparasitoid species
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JEFFREY A. HARVEY RIETA GOLS HELEN SNAAS MIRIAMA MALCICKA BERTANNE VISSER 《Ecological Entomology》2015,40(2):114-122
1. The optimisation theory predicts that insect mothers should oviposit on resources on which they attain the highest exclusive fitness. The development of parasitoid wasps is dependent on limited host resources that are often not much larger than the adult parasitoid. 2. In the present study preference and development in three congeneric species of secondary hyperparasitoids attacking cocoons of two congeneric primary parasitoids that differ significantly in size were compared. Gelis agilis (Fabricius) and G. acarorum (L.) are wingless hyperparasitoids that forage in grassy habitats, whereas G. areator (Panzer) is fully winged and forages higher in the canopy of forbs. 3. The three species were reared on cocoons containing pupae of a small gregarious endoparasitoid, Cotesia glomerata (L.), and a larger solitary species, C. rubecula (Marshall), both of which develop in the caterpillars of pierid butterflies. 4. Adult mass was correlated with initial cocoon mass in all three species, whereas development time was unaffected. Wasps were larger when developing in C. rubecula. However, for a given host mass, wasps were larger when developing on the smaller host, C. glomerata. This suggests that there is a physiological limit to hyperparasitoid size that was exceeded when C. rubecula served as host. 5. All three hyperparasitoids strongly preferred to attack cocoons of the larger species, C. rubecula, often avoiding cocoons of C. glomerata entirely. 6. Preference and performance are correlated in the three Gelis species. However, owing to variation in the distribution and thus abundance of their hosts, it is argued that cumulative fitness may be still higher in the smaller host species. 相似文献
987.
DANIEL H. NUSSEY MICHELLE N. CLEMENTS FIONA E. GUINNESS ALISON MORRIS SEAN MORRIS JOSEPHINE M. PEMBERTON LOESKE E. B. KRUUK TIM H. CLUTTON‐BROCK 《Global Change Biology》2011,17(7):2455-2469
Most evidence for advances in phenology of in response to recent climate warming in wild vertebrate populations has come from long‐term studies of birds. Few studies have either documented phenological advances or tested their climatic causes and demographic consequences in wild mammal systems. Using a long‐term study of red deer on the Isle of Rum, Scotland, we present evidence of significant temporal trends in six phenological traits: oestrus date and parturition date in females, and antler cast date, antler clean date, rut start date and rut end date in males. These traits advanced by between 5 and 12 days across a 28‐year study period. Local climate measures associated with plant growth in spring and summer (growing degree days) increased significantly over time and explained a significant amount of variation in all six phenological traits, largely accounting for temporal advances observed in some of the traits. However, there was no evidence for temporal changes in key female reproductive performance traits (offspring birth weight and offspring survival) in this population, despite significant relationships between these traits and female phenology. In males, average antler weights increased over time presumably as a result of improved resource availability and physiological condition through spring and summer. There was no evidence for any temporal change in average male annual breeding success, as might be expected if the timing of male rutting behaviour was failing to track advances in the timing of oestrus in females. Our results provide rare evidence linking phenological advances to climate warming in a wild mammal and highlight the potential complexity of relationships between climate warming, phenology and demography in wild vertebrates. 相似文献
988.
J. Simpore S. Pignatelli P. Melis S. Musumeci 《International Journal of Anthropology》2002,17(2):77-89
We have studied To study the incidence of hemoglobinopathies (Hb C and Hb S) we have examined in 15,367 students, aged 11.4+/−4.64
years (median 11; range 1–26), living in Burkina Faso (12,019 were students of 23 public schools of Ouagadougou and 3348 students
of 7 public schools situated in six villages about 12–35 Km from Ouagadougou).
In all groups studied, β S and β C gene frequencies were age dependent there was an age dependency of the β S and β C gene
frequencies, since the advantage of HbS carriers in a malarial region is prevalently expressed in the first years of life.
In fact, β C the gene frequency of β C increases, and the β S decreases with age. The Mossi, living prevalently mainly in
Ouagadougou, show a gene frequency which is similar to the Bissa ethnic groups, where the C gene frequencies (0.116 and 0.118)
wereare more higher than the S (0.049 and 0.044 respectively). On the contrary in the Peuhl ethnic group the β C and β S gene
frequencies (0.049 and 0.049) were are the same, while in the Yorouba ethnic group immigrated from Nigeria a prevalence of
β S gene frequency is higher (0.117) than over the β C (0.068)gene frequencies was found in the Yorouba ethnic group, who
is immigrated from Nigeria, showing that different gene frequencies are found in different ethniae ethnic groupscorrespond
to different gene frequencies. 相似文献
989.
990.
Stephan Rssner Lars Sjstrm Rudolf Noack A. Edo Meinders Giorgio Noseda 《Obesity (Silver Spring, Md.)》2000,8(1):49-61
Objective: To determine the effect of orlistat, a new lipase inhibitor, on long‐term weight loss, to determine the extent to which orlistat treatment minimizes weight regain in a second year of treatment, and to assess the effects of orlistat on obesity‐related risk factors. Research Methods and Procedures: This was a 2‐year, multicenter, randomized, double‐blind, placebo‐controlled study. Obese patients (body mass index 28 to 43 kg/m2) were randomized to placebo or orlistat (60 or 120 mg) three times a day, combined with a hypocaloric diet during the first year and a weight maintenance diet in the second year of treatment to prevent weight regain. Changes in body weight, lipid profile, glycemic control, blood pressure, quality of life, safety, and tolerability were measured. Results: Orlistat‐treated patients lost significantly more weight (p < 0.001) than placebo‐treated patients after Year 1 (6.6%, 8.6%, and 9.7% for the placebo, and orlistat 60 mg and 120 mg groups, respectively). During the second year, orlistat therapy produced less weight regain than placebo (p = 0.005 for orlistat 60 mg; p < 0.001 for orlistat 120 mg). Several obesity‐related risk factors improved significantly more with orlistat treatment than with placebo. Orlistat was generally well tolerated and only 6% of orlistat‐treated patients withdrew because of adverse events. Orlistat leads to predictable gastrointestinal effects related to its mode of action, which were generally mild, transient, and self‐limiting and usually occurred early during treatment. Discussion: Orlistat administered for 2 years promotes weight loss and minimizes weight regain. Additionally, orlistat therapy improves lipid profile, blood pressure, and quality of life. 相似文献