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871.
872.
Pawel Fedurek Robin I. M. Dunbar† & for the British Academy Centenary Research Project 《Ethology : formerly Zeitschrift fur Tierpsychologie》2009,115(6):566-575
Grooming might be a resource that is offered in exchange for some benefit (e.g. access to a feeding site or coalitionary support) or it might be a mechanism for building and servicing social relationships, whose function, in turn, is to facilitate the exchange of resources and services. Bi-directional (or simultaneous mutual) grooming is unusually common among chimpanzees (though rare in other primates) and we suggest that this might be because it is an especially strong indicator of social bonding. Because the bonding role of bi-directional grooming offers substantially different predictions from the interpretation offered by the models based on reciprocal altruism (RA), we use a critical tests methodology (i.e. tests that unequivocally support one hypothesis at the expense of the other) to differentiate between the bonding and RA hypotheses. We use data on the dynamics of grooming interactions from a captive group of chimpanzees ( Pan troglodytes ) to show that dominant individuals tolerated the individuals with whom they performed bi-directional grooming more than they did those who typically provided them unidirectional grooming. Dominants rejected and terminated grooming sessions more often with the individuals who provided them with mostly unidirectional grooming than with those with whom they groomed bi-directionally. In addition, animals engaged in bi-directional grooming more often with both relatives and those with whom they were often in proximity. These results support the bonding model of mutually reciprocated grooming at the expense of the RA model, and suggest that, at least in chimpanzees, simultaneous mutual grooming may play a particularly important role in social bonding. 相似文献
873.
874.
Akira Shibanuma Evelyn Korkor Ansah Kimiyo Kikuchi Francis Yeji Sumiyo Okawa Charlotte Tawiah Keiko Nanishi Sheila Addei John Williams Kwaku Poku Asante Abraham Oduro Seth Owusu-Agyei Margaret Gyapong Gloria Quansah Asare Junko Yasuoka Abraham Hodgson Masamine Jimba the Ghana EMBRACE Implementation Research Project Team 《PLoS medicine》2021,18(6)
BackgroundIn low- and middle-income countries (LMICs), the continuum of care (CoC) for maternal, newborn, and child health (MNCH) is not always complete. This study aimed to evaluate the effectiveness of an integrated package of CoC interventions on the CoC completion, morbidity, and mortality outcomes of woman–child pairs in Ghana.Methods and findingsThis cluster-randomized controlled trial (ISRCTN: 90618993) was conducted at 3 Health and Demographic Surveillance System (HDSS) sites in Ghana. The primary outcome was CoC completion by a woman–child pair, defined as receiving antenatal care (ANC) 4 times or more, delivery assistance from a skilled birth attendant (SBA), and postnatal care (PNC) 3 times or more. Other outcomes were the morbidity and mortality of women and children. Women received a package of interventions and routine services at health facilities (October 2014 to December 2015). The package comprised providing a CoC card for women, CoC orientation for health workers, and offering women with 24-hour stay at a health facility or a home visit within 48 hours after delivery. In the control arm, women received routine services only. Eligibility criteria were as follows: women who gave birth or had a stillbirth from September 1, 2012 to September 30, 2014 (before the trial period), from October 1, 2014 to December 31, 2015 (during the trial period), or from January 1, 2016 to December 31, 2016 (after the trial period). Health service and morbidity outcomes were assessed before and during the trial periods through face-to-face interviews. Mortality was assessed using demographic surveillance data for the 3 periods above. Mixed-effects logistic regression models were used to evaluate the effectiveness as difference in differences (DiD). For health service and morbidity outcomes, 2,970 woman–child pairs were assessed: 1,480 from the baseline survey and 1,490 from the follow-up survey. Additionally, 33,819 cases were assessed for perinatal mortality, 33,322 for neonatal mortality, and 39,205 for maternal mortality. The intervention arm had higher proportions of completed CoC (410/870 [47.1%]) than the control arm (246/620 [39.7%]; adjusted odds ratio [AOR] for DiD = 1.77; 95% confidence interval [CI]: 1.08 to 2.92; p = 0.024). Maternal complications that required hospitalization during pregnancy were lower in the intervention (95/870 [10.9%]) than in the control arm (83/620 [13.4%]) (AOR for DiD = 0.49; 95% CI: 0.29 to 0.83; p = 0.008). Maternal mortality was 8/6,163 live births (intervention arm) and 4/4,068 live births during the trial period (AOR for DiD = 1.60; 95% CI: 0.40 to 6.34; p = 0.507) and 1/4,626 (intervention arm) and 9/3,937 (control arm) after the trial period (AOR for DiD = 0.11; 95% CI: 0.11 to 1.00; p = 0.050). Perinatal and neonatal mortality was not significantly reduced. As this study was conducted in a real-world setting, possible limitations included differences in the type and scale of health facilities and the size of subdistricts, contamination for intervention effectiveness due to the geographic proximity of the arms, and insufficient number of cases for the mortality assessment.ConclusionsThis study found that an integrated package of CoC interventions increased CoC completion and decreased maternal complications requiring hospitalization during pregnancy and maternal mortality after the trial period. It did not find evidence of reduced perinatal and neonatal mortality.Trial registrationThe study protocol was registered in the International Standard Randomised Controlled Trial Number Registry (90618993).Akira Shibanuma and co-workers study a package of maternal and child health interventions in a cluster-randomized trial done in Ghana. 相似文献
875.
876.
877.
Lianquan Zhang Li Zhang Yang Yen a Triticeae Research Institute Sichuan Agricultural University Wenjiang Sichuan China b Key Laboratory of Adaptation Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining China c 《Acta Genetica Sinica》2011,(2)
Doubled haploid(DH) populations are useful to scientists and breeders in both crop improvement and basic research.Current methods of producing DHs usually need in vitro culture for extracting haploids and chemical treatment for chromosome doubling.This report describes a simple method for synthesizing DHs(SynDH) especially for allopolyploid species by utilizing meiotic restitution genes.The method involves three steps:hybridization to induce recombination,interspecific hybridization to extract haploids,a... 相似文献
878.
An analysis of spontaneous human cortical EEG activity to odours 总被引:1,自引:1,他引:0
Toller S. Van; Behan J.; Howells P.; Kendal-Reed M.; Richardson A.; The Warwick Human Chemoreception Research Group 《Chemical senses》1993,18(1):1-16
Using single trial presentation of odours, mapping of spontaneousEEG was made in naive subjects. Systematic increases in EEGamplitudes for alpha (813 Hz) frequency were shown forthe odours used and discrimination of odours was shown by specificelectrodes. These were mainly in the area bounded by International10/20 scalp locations CP1, PZ, CP2, TCP2 and C4. It was alsoshown that EEG recordings from more anterior electrodes couldbe related to psychometric responses. The findings showed thatstatistically reliable electrical amplitudes to odour presentationswere discernible in the noisy EEG environment on the surfaceof the brain. 相似文献
879.
Dr. Shiriki K. Kumanyika Mark A. Espeland Judy L. Bahnson Juliene B. Bottom Jeanne B. Charleston Steve Folmar Alan C. Wilson Paul K. Whelton TONE Cooperative Research Group 《Obesity (Silver Spring, Md.)》2002,10(2):96-106
Objective: To compare weight loss in blacks and whites in the Trial of Nonpharmacologic Interventions in the Elderly (TONE). Research Methods and Procedures: TONE enrolled 421 overweight white and 164 overweight black adults, 60 to 79 years old, with blood pressure well-controlled on a single, antihypertensive drug. Drug therapy withdrawal was attempted 3 months after randomization to counseling for weight loss, sodium reduction, both weight loss and sodium reduction, or to usual care, with follow-up for 15 to 36 months after enrollment. Statistical procedures included repeated measures analysis of covariance and logistic and proportional hazards regression. Results: In the weight-loss condition, net weight change (in kilograms) was −2.7 in blacks and −5.9 in whites (p < 0.001; ethnic difference, p = 0.0002) at 6 months and −2.0 (p < 0.05) in blacks and −4.9 (p < 0.001) in whites at the end of follow-up (ethnic difference, p = 0.007). In weight/sodium, net weight change was −2.1 (p < 0.01) in blacks and −2.8 (p < 0.001) in whites at 6 months, and −1.9 in blacks and −1.7 in whites at the end of follow-up (p < 0.05; ethnic difference, p > 0.5). Exploratory analyses suggested a more favorable pattern of weight change in blacks than in whites from 6 months onward. There was no ethnic difference in blood pressure outcomes. Discussion: Whites lost more weight than blacks without, but not with, a concurrent focus on sodium reduction. 相似文献
880.