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961.
Edda Bjork Thordardottir Li Yin Arna Hauksdottir Ellenor Mittendorfer-Rutz Anna-Clara Hollander Christina M. Hultman Paul Lichtenstein Weimin Ye Filip K. Arnberg Fang Fang Emily A. Holmes Unnur Anna Valdimarsdottir 《PLoS medicine》2020,17(12)
BackgroundIn recent decades, millions of refugees and migrants have fled wars and sought asylum in Europe. The aim of this study was to quantify the risk of mortality and major diseases among migrants during the 1991–2001 Balkan wars to Sweden in comparison to other European migrants to Sweden during the same period.Methods and findingsWe conducted a register-based cohort study of 104,770 migrants to Sweden from the former Yugoslavia during the Balkan wars and 147,430 migrants to Sweden from 24 other European countries during the same period (1991–2001). Inpatient and specialized outpatient diagnoses of cardiovascular disease (CVD), cancer, and psychiatric disorders were obtained from the Swedish National Patient Register and the Swedish Cancer Register, and mortality data from the Swedish Cause of Death Register. Adjusting for individual-level data on sociodemographic characteristics and emigration country smoking prevalence, we used Cox regressions to contrast risks of health outcomes for migrants of the Balkan wars and other European migrants. During an average of 12.26 years of follow-up, being a migrant of the Balkan wars was associated with an elevated risk of being diagnosed with CVD (HR 1.39, 95% CI 1.34–1.43, p < 0.001) and dying from CVD (HR 1.45, 95% CI 1.29–1.62, p < 0.001), as well as being diagnosed with cancer (HR 1.16, 95% CI 1.08–1.24, p < 0.001) and dying from cancer (HR 1.27, 95% CI 1.15–1.41, p < 0.001), compared to other European migrants. Being a migrant of the Balkan wars was also associated with a greater overall risk of being diagnosed with a psychiatric disorder (HR 1.19, 95% CI 1.14–1.23, p < 0.001), particularly post-traumatic stress disorder (HR 9.33, 95% CI 7.96–10.94, p < 0.001), while being associated with a reduced risk of suicide (HR 0.68, 95% CI 0.48–0.96, p = 0.030) and suicide attempt (HR 0.57, 95% CI 0.51–0.65, p < 0.001). Later time period of migration and not having any first-degree relatives in Sweden at the time of immigration were associated with greater increases in risk of CVD and psychiatric disorders. Limitations of the study included lack of individual-level information on health status and behaviors of migrants at the time of immigration.ConclusionsOur findings indicate that migrants of the Balkan wars faced considerably elevated risks of major diseases and mortality in their first decade in Sweden compared to other European migrants. War migrants without family members in Sweden or with more recent immigration may be particularly vulnerable to adverse health outcomes. Results underscore that persons displaced by war are a vulnerable group in need of long-term health surveillance for psychiatric disorders and somatic disease.Edda Bjork Thordardottir and co-workers study health outcomes among migrants from the former Yugoslavia to Sweden. 相似文献
962.
Coarse-grained (CG) models in molecular dynamics (MD) are powerful tools to simulate the dynamics of large biomolecular systems on micro- to millisecond timescales. However, the CG model, potential energy terms, and parameters are typically not transferable between different molecules and problems. So parameterizing CG force fields, which is both tedious and time-consuming, is often necessary. We present RedMDStream, a software for developing, testing, and simulating biomolecules with CG MD models. Development includes an automatic procedure for the optimization of potential energy parameters based on metaheuristic methods. As an example we describe the parameterization of a simple CG MD model of an RNA hairpin. 相似文献
963.
Mark S. Tichenor John M. Keith William M. Jones Joan M. Pierce Jeff Merit Natalie Hawryluk Mark Seierstad James A. Palmer Michael Webb Mark J. Karbarz Sandy J. Wilson Michelle L. Wennerholm Filip Woestenborghs Dominiek Beerens Lin Luo Sean M. Brown Marlies De Boeck Sandra R. Chaplan J. Guy Breitenbucher 《Bioorganic & medicinal chemistry letters》2012,22(24):7357-7362
The structure–activity relationships for a series of heteroaryl urea inhibitors of fatty acid amide hydrolase (FAAH) are described. Members of this class of inhibitors have been shown to inactivate FAAH by covalent modification of an active site serine with subsequent release of an aromatic amine from the urea electrophile. Systematic Ames II testing guided the optimization of urea substituents by defining the structure–mutagenicity relationships for the released aromatic amine metabolites. Potent FAAH inhibitors were identified having heteroaryl amine leaving groups that were non-mutagenic in the Ames II assay. 相似文献
964.
965.
Filip Moučka 《Molecular simulation》2013,39(8):660-672
Various technical aspects affecting the efficiency of a recently proposed novel Monte Carlo (MC) simulation scheme based on biased simultaneous displacements/rotations of all particles of the system are investigated using two polarisable models of water, the Chialvo–Cummings and Brodholt–Sampoli–Vallauri models, as a test case. Necessary expressions for polarisable site–site interaction models are derived along with a novel smoothing of the potential at the cut-off distance. In addition to the common thermodynamic and structural properties, the mean-squared displacements, rotation relaxation, speed of equilibration (translational order parameter, TOP) and autocorrelation coefficients have been computed as well, in order to assess the efficiency of the method. Gain in speed by parallelisation has also been examined. Performance of the method is coumpared with both the standard one-particle move method and the available approximate methods. It is shown that the multi-particle move (MPM) method performs about by a factor of 10 faster for the systems considered when compared with the common MC scheme, and several times faster when compared with the approximate methods. Parallelised codes of the MPM method may then perform about 70 times faster than the conventional MC. These conclusions hold true for the system size simulated (N = 256) because the efficiency of the multi-particle method depends on the size of the system: its efficiency even increases with increasing number of particles. 相似文献
966.
Coccolith dissolution together with post-mortem morphological features are immensely important phenomena that can affect assemblage compositions, complicate taxonomic identification as well as provide valuable palaeoenvironmental insights. This study summarizes the effects of pH oscillations on post-mortem coccolith morphologies and the abundances and compositions of calcareous nannoplankton assemblages in three distinct types of material—(i) Cretaceous chalk, (ii) Miocene marls, and (iii) late Holocene calcareous ooze. Two independent experimental runs within a semi-enclosed system setting were realized to observe assemblage alterations. One experiment was realized with the presence of bacteria and, in contrast, the second one inhibited their potential effect on the studied system. The pH was gradually decreased within the range of 8.3–6.4 using a reaction of CO2 with H2O forming weak carbonic acid (H2CO3), thereby affecting []. Further, a subsequent overgrowth study was carried out during spontaneous degassing accompanied by a gradual pH rise. The experiment revealed that the process and intensity of coccolith corrosion and subsequent overgrowth build-ups are influenced by a plethora of different factors such as (i) pH and associated seawater chemistry, (ii) mineral composition of the sediment, (iii) the presence of coccoliths within a protective substrate (faecal pellets, pores, pits), and (iv) the presence/absence of bacteria. Nannoplankton assemblages with corroded coccoliths or with coccoliths with overgrowth build-ups showed that the observed relative abundances of taxa experienced alteration from the original compositions. Additionally, extreme pH oscillations may result in enhanced morphological changes that make coccoliths unidentifiable structures, and might even evoke the absence of coccoliths in the fossil record. 相似文献
967.
Anurag Chaturvedi Joost A. M. Raeymaekers Filip A. M. Volckaert 《Molecular ecology resources》2014,14(4):768-777
An intriguing question in biology is how the evolution of gene regulation is shaped by natural selection in natural populations. Among the many known regulatory mechanisms, regulation of gene expression by microRNAs (miRNAs) is of critical importance. However, our understanding of their evolution in natural populations is limited. Studying the role of miRNAs in three‐spined stickleback, an important natural model for speciation research, may provide new insights into adaptive polymorphisms. However, lack of annotation of miRNA genes in its genome is a bottleneck. To fill this research gap, we used the genome of three‐spined stickleback to predict miRNAs and their targets. We predicted 1486 mature miRNAs using the homology‐based miRNA prediction approach. We then performed functional annotation and enrichment analysis of these targets, which identified over‐represented motifs. Further, a database resource (GAmiRdb) has been developed for dynamically searching miRNAs and their targets exclusively in three‐spined stickleback. Finally, the database was used in two case studies focusing on freshwater adaptation in natural populations. In the first study, we found 44 genomic regions overlapping with predicted miRNA targets. In the second study, we identified two SNPs altering the MRE seed site of sperm‐specific glyceraldehyde‐3‐phosphate gene. These findings highlight the importance of the GAmiRdb knowledge base in understanding adaptive evolution. 相似文献
968.
969.
Effect of adrenalectomy and corticosterone on cocaine-induced sensitization in rats. 总被引:5,自引:0,他引:5
E Przegaliński M Filip J Siwanowicz E Nowak 《Journal of physiology and pharmacology》2000,51(2):193-204
Effects of adrenalectomy (ADX) and corticosterone (CORT) on the development and expression of sensitization to the locomotor effect of cocaine (COC) were studied in rats. Sensitization was evoked by 5 daily injections of COC (10 mg/kg) and measured after a challenge dose of the drug (10 mg/kg) after a 5-day withdrawal (on day 10 of the experiment). ADX, performed before the start of COC administration, completely blocked the manifestation of COC-induced sensitization. In contrast, ADX performed on animals already sensitized to COC did not affect the sensitized locomotor activity response to a challenge dose of COC (on day 18). Pretreatment with CORT, 10 mg/kg, but not 5 mg/kg, before each of the 5 daily COC injections facilitated the development of COC sensitization, tested after a 5-day withdrawal. When pretreated with CORT alone (10 mg/kg), the challenge dose of COC administered on day 10 induced cross-sensitization to CORT. CORT (10 mg/kg) injected acutely before COC on day 10, potentiated the expression of COC sensitization. When given alone, on day 10 CORT (5-10 mg/kg) induced an increase in the locomotor activity of rats pretreated daily (5 injections) with COC. No drug treatment induced conditioned locomotion, as measured after saline challenge on day 8. Our results indicate that CORT facilitates the development and expression of COC sensitization, while ADX blocks the initiation of the behavioral phenomenon only. Moreover, there takes place cross-sensitization between CORT and COC, which indicates a close relationship between the drug-related mechanism and behavioral sensitization. 相似文献
970.
J L Valentine W S Yamanashi A A Patil R Paulsen D L Hill P D Lester O F Filip 《Physiological chemistry and physics and medical NMR》1986,18(2):103-108
A magnetic resonance (MR) imaging scanner operated at 0.5 T with a specially constructed receiving coil was used to measure volumes of primary spontaneous tumors in rats and guinea pigs. The coil was used to improve the signal to noise ratio (S/N) of the MR images of tumors in these small animals. The tumor volume was determined by the summation of the volume of contiguous slices or ellipsoid approximation. The accuracy of the volume measurement was better when the numerical integration was used in calculating the slice volume. The open sided saddle (OSS) coil used as the receiving coil gave better S/N than that of the standard head coil. 相似文献