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981.
Alicia R. Pérez de Rosas Elsa L. Segura Octavio Fusco Adolfo L. Bareiro Guiñazú Beatriz A. García 《Genetica》2013,141(1-3):107-117
Fine scale patterns of genetic structure and dispersal in Triatoma infestans populations from Argentina was analysed. A total of 314 insects from 22 domestic and peridomestic sites from the locality of San Martín (Capayán department, Catamarca province) were typed for 10 polymorphic microsatellite loci. The results confirm subdivision of T. infestans populations with restricted dispersal among sampling sites and suggest inbreeding and/or stratification within the different domestic and peridomestic structures. Spatial correlation analysis showed that the scale of structuring is approximately of 400 m, indicating that active dispersal would occur within this distance range. It was detected difference in scale of structuring among sexes, with females dispersing over greater distances than males. This study suggests that insecticide treatment and surveillance should be extended within a radius of 400 m around the infested area, which would help to reduce the probability of reinfestation by covering an area of active dispersal. The inferences made from fine-scale spatial genetic structure analyses of T. infestans populations has demonstrated to be important for community-wide control programs, providing a complementary approach to help improve vector control strategies. 相似文献
982.
Very close similarities between the fossil genera Callimothallus Dilcher, 1965 and Microthallites Dilcher, 1965 and recent representatives of the green algae Ulvella P. L. &; H. M. Crouan, 1859, seem to rule out the assumption that fossil, disciform and radiate palynomorph microfossils are representatives of microthyrioaceous fungi. On the basis of the morphology of fossil Ulvella, a model of the general morpohlogy of encrusting, palynomorph algae is constructed. The model includes 5 morphological characters that may only be applied to encrusting life-forms and in particular not to planktonic algae. These characters, therefore, in future palynological research may serve to distinguish benthic algae from planktonic algae. A new fossil alga, Ulvella nannae sp. nov. is described. 相似文献
983.
Laura Espin Mercedes Almela Vanesa Hidalgo Carolina Villada Alicia Salvador Jesus Gomez-Amor 《Hormones and behavior》2013,63(5):759-765
This study explores the influence of pre-learning stress on performance on declarative memory tasks in healthy young adults in relation to sex and menstrual cycle phase. The sample was composed of 119 students (32 men and 87 women) from 18 to 25 years of age. The women were tested in different hormonal stages (30 in follicular phase, 34 in luteal phase, and 23 using oral contraceptives). The participants were exposed to the Trier Social Stress Test (TSST) or a control condition. Afterwards, their memory performance was measured using a standardized memory test (Rey's Auditory Verbal Learning Test). In the control condition, all groups of women recalled more words than men, but these differences disappeared in the group exposed to TSST because men's performance on the memory test improved, but only to the level of women. In addition, our data suggest that in women the relationship between cortisol and memory can be modulated by sex hormone levels, since in luteal women a negative relationship was found between memory performance and peak cortisol level. These results confirm that sex differences need to be considered in the relationship between pre-learning stress and memory performance. 相似文献
984.
985.
Alicia Álvarez S. Ivan Perez Diego H. Verzi 《Biological journal of the Linnean Society. Linnean Society of London》2013,110(4):898-913
Caviomorph rodents represent an excellent model to explore morphological diversification on a macroevolutionary scale, as they are ecologically and morphologically diverse. We analysed cranial shape variation using geometric morphometrics and phylogenetic comparative methods. Most variation involved the shape of the rostrum, basicranium, and cranial vault, and clearly matched the phylogenetic structure. At the same time, a strong allometric pattern was associated with the length of the rostrum and cranial vault, size of the auditory bulla, and depth of the zygomatic arch. After accounting for size influence, and taking phylogenetic structure into account, shape variation was significantly associated with habitat. Our results highlight the presence of complex relationships between morphological, phylogenetic, and ecological dimensions in the diversification of the caviomorph cranium. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 898–913. 相似文献
986.
Marina Stein Laura Zalazar Juana Alicia Willener Francisco Ludue?a Almeida Walter Ricardo Almirón 《Memórias do Instituto Oswaldo Cruz》2013,108(5):563-571
Studies were conducted to determine the selection of humans, chickens
and rabbits by Culicidae in three different environments in the province of
Chaco, Argentina. Mosquitoes were collected fortnightly using cylindrical metal
traps containing animal bait (chickens and rabbits). The mosquitoes were
collected between June 2001-May 2002. During the same period and with the same
frequency, mosquitoes biting the human operators of the traps were collected
during the first 15 min of exposure within different time intervals: from 09:00
am-11:00 am, 01:00 pm-03:00 pm, 05:00 pm-07:00 pm and 09:00 pm-10:00 pm. A total
of 19,430 mosquitoes of 49 species belonging to 10 genera were collected.
Culex species mainly selected chicken bait and
Wyeomyia species selected rabbit bait.
Ochlerotatus and Psorophora species were
more abundant in rabbit-baited traps. Anopheles triannulatus,
Coquillettidia nigricans, Ochlerotatus
scapularis, Mansonia titillans and
Psorophora albigenu showed a strong attraction for human
bait. The Anopheles, Coquillettidia,
Culex and Mansonia species were more
active between 05:00 pm-09:00 pm, while Ochlerotatus,
Psorophora, Haemagogus and
Wyeomyia were most active from 09:00 am-07:00 pm. This
study provides additional information about the biology and ecology of arbovirus
vectors in Chaco. 相似文献
987.
Gilbert J. Kersh Kelly A. Fitzpatrick Joshua S. Self Rachael A. Priestley Aubree J. Kelly R. Ryan Lash Nicola Marsden-Haug Randall J. Nett Adam Bjork Robert F. Massung Alicia D. Anderson 《Applied and environmental microbiology》2013,79(5):1697-1703
Q fever is a zoonotic disease caused by inhalation of the bacterium Coxiella burnetii. Ruminant livestock are common reservoirs for C. burnetii, and bacteria present in aerosols derived from the waste of infected animals can infect humans. The significance of infection from material deposited in the environment versus transmission directly from infected animals is not known. In 2011, an outbreak of Q fever cases on farms in Washington and Montana was associated with infected goats. A study was undertaken to investigate the quantity and spatial distribution of C. burnetii in the environment of these goat farms. Soil, vacuum, and sponge samples collected on seven farms epidemiologically linked to the outbreak were tested for the presence of C. burnetii DNA by quantitative PCR. Overall, 70.1% of the samples were positive for C. burnetii. All farms had positive samples, but the quantity of C. burnetii varied widely between samples and between farms. High quantities of C. burnetii DNA were in goat housing/birthing areas, and only small quantities were found in samples collected more than 50 m from these areas. Follow-up sampling at one of the farms 1 year after the outbreak found small quantities of C. burnetii DNA in air samples and large quantities of C. burnetii persisting in soil and vacuum samples. The results suggest that the highest concentrations of environmental C. burnetii are found in goat birthing areas and that contamination of other areas is mostly associated with human movement. 相似文献
988.
Marisol López Pedro Dorado Alberto Ortega Eva Peñas-Lledó Nancy Monroy Irma Silva-Zolezzi Jesús Cobaleda Alicia Gallego-Aguilera María Elisa Alonso Adrián LLerena 《Molecular biology reports》2013,40(4):3187-3192
UDP-glucuronosyltransferase 1A4 (UGT1A4) is a phase II drug-metabolizing enzyme that catalyzes the glucuronidation of many clinically-important drugs. Interethnic differences in the genetic polymorphism of UGT1A4 have been reported; however, there is no information in Mexican Mestizos (MMs) and Spaniards (SPs). Furthermore, MM is an admixed population with 26 % of Caucasian genes mainly from Spain. Therefore, this study aimed to investigate the potential differences between 318 SPs and 248 MMs healthy individuals regarding UGT1A4*1b, UGT1A4*2 and UGT1A4*3 alleles and to compare the observed frequencies with those previously reported in different populations. The allelic frequencies of the three UGT1A4 polymorphisms showed interethnic differences between MMs and SPs (p < 0.05). The analyzed SNPs variants in this genetic region were not in linkage disequilibrium (LD) for the MM population, suggesting that these mutations have arisen independently in the same genetic background. In contrast, UGT1A4*2 and UGT1A4*3 were in LD in the SP population. Comparison of present data with other in different ethnic groups revealed that the frequencies of UGT1A4*2 and UGT1A4*3 in SP were similar to other Caucasians and higher than in Asians, whereas in MMs were lower than in Caucasians and higher than in Asians only for UGT1A4*2. Present results could be helpful to improve the use of UGT1A4 drug substrates in order to adjust them to the ethnic background of a given population, specifically for Hispanics. 相似文献
989.
Yan V. Sun Alicia K. Smith Karen N. Conneely Qiuzhi Chang Weiyan Li Alicia Lazarus Jennifer A. Smith Lynn M. Almli Elisabeth B. Binder Torsten Klengel Dorthie Cross Stephen T. Turner Kerry J. Ressler Sharon L. R. Kardia 《Human genetics》2013,132(9):1027-1037
Cigarette smoking is an environmental risk factor for many chronic diseases, and disease risk can often be managed by smoking control. Smoking can induce cellular and molecular changes, including epigenetic modification, but the short- and long-term epigenetic modifications caused by cigarette smoking at the gene level have not been well understood. Recent studies have identified smoking-related DNA methylation (DNAm) sites in Caucasians. To determine whether the same DNAm sites associate with smoking in African Americans, and to identify novel smoking-related DNAm sites, we conducted a methylome-wide association study of cigarette smoking using a discovery sample of 972 African Americans, and a replication sample of 239 African Americans with two array-based methods. Among 15 DNAm sites significantly associated with smoking after correction for multiple testing in our discovery sample, 5 DNAm sites are replicated in an independent cohort, and 14 sites in the replication sample have effects in the same direction as in the discovery sample. The top two smoking-related DNAm sites in F2RL3 (factor II receptor-like 3) and GPR15 (G-protein-coupled receptor 15) observed in African Americans are consistent with previous findings in Caucasians. The associations between the replicated DNAm sites and smoking remain significant after adjusting for genetic background. Despite the distinct genetic background between African Americans and Caucasians, the DNAm from the two ethnic groups shares common associations with cigarette smoking, which suggests a common molecular mechanism of epigenetic modification influenced by environmental exposure. 相似文献
990.
Catherine R. Armbruster Terri S. Forster Rodney M. Donlan Heather A. O'Connell Alicia M. Shams 《Biofouling》2013,29(10):1129-1139
Water in healthcare environments can be a source for healthcare-associated infections (HAI). However, information on the exposure risk to opportunistic pathogens in potable water distribution systems (PWDS) is lacking. Laboratory studies characterizing the interaction of opportunistic pathogens with biofilms are needed to understand their role in water systems within healthcare facilities. A stable, repeatable, PWDS multi-species biofilm model comprising Sphingomonas paucimobilis, Methylobacterium sp., Delftia acidovorans, and Mycobacterium mucogenicum was developed in the CDC Biofilm Reactor (CBR), reaching 6 log10 CFU cm?2 within 6 days. The model was used to investigate the interaction of the opportunistic pathogen M. mucogenicum with the other species, and to determine the efficacy of monochloramine (NH2Cl) as a disinfectant against 2-week-old biofilms. Addition of 1 or 2 mg l?1 NH2Cl resulted in the same or an increased log density of viable M. mucogenicum in the biofilm while inactivating some of the Proteobacteria. Although M. mucogenicum preferentially resided in the biofilm, NH2Cl exposure caused release of viable M. mucogenicum from the biofilm into the water. Additional studies with this model should determine if sodium hypochlorite has a comparative effect and if other nontuberculous mycobacteria (NTM) respond to NH2Cl similarly. 相似文献