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121.
The rates at which birds use energy may have profound effects on fitness, thereby influencing physiology, behavior, ecology and evolution. Comparisons of standardized metabolic rates (e.g., lower and upper limits of metabolic power output) present a method for elucidating the effects of ecological and evolutionary factors on the interface between physiology and life history in birds. In this paper we review variation in avian metabolic rates [basal metabolic rate (BMR; minimum normothermic metabolic rate), ... 相似文献
122.
环境光对哺乳动物昼夜节律和大脑功能的影响 总被引:1,自引:0,他引:1
昼夜循环对人类和其他动物的生理和行为有着巨大的影响。光照条件能影响动物的视觉成像,并通过向大脑中的生物钟中心发送信号来调整生理和行为的节律。环境光向生物钟传递信号的系统包含了一个复杂的神经递质复合体-受体-第二信使系统。在夜间曝光能迅速启动下丘脑视交叉上核中大量相关的早期基因。此外,许多白天活动的物种,通常都是在光照条件下获得认知。本文综述了环境光对哺乳动物睡眠、生物节律、大脑认知能力和基因表达等生理和行为方面的影响。 相似文献
123.
Hajo Grundmann David M. Aanensen Cees C. van den Wijngaard Brian G. Spratt Dag Harmsen Alexander W. Friedrich the European Staphylococcal Reference Laboratory Working Group? 《PLoS medicine》2010,7(1)
Background
Staphylococcus aureus is one of the most important human pathogens and methicillin-resistant variants (MRSAs) are a major cause of hospital and community-acquired infection. We aimed to map the geographic distribution of the dominant clones that cause invasive infections in Europe.Methods and Findings
In each country, staphylococcal reference laboratories secured the participation of a sufficient number of hospital laboratories to achieve national geo-demographic representation. Participating laboratories collected successive methicillin-susceptible (MSSA) and MRSA isolates from patients with invasive S. aureus infection using an agreed protocol. All isolates were sent to the respective national reference laboratories and characterised by quality-controlled sequence typing of the variable region of the staphylococcal spa gene (spa typing), and data were uploaded to a central database. Relevant genetic and phenotypic information was assembled for interactive interrogation by a purpose-built Web-based mapping application. Between September 2006 and February 2007, 357 laboratories serving 450 hospitals in 26 countries collected 2,890 MSSA and MRSA isolates from patients with invasive S. aureus infection. A wide geographical distribution of spa types was found with some prevalent in all European countries. MSSA were more diverse than MRSA. Genetic diversity of MRSA differed considerably between countries with dominant MRSA spa types forming distinctive geographical clusters. We provide evidence that a network approach consisting of decentralised typing and visualisation of aggregated data using an interactive mapping tool can provide important information on the dynamics of MRSA populations such as early signalling of emerging strains, cross border spread, and importation by travel.Conclusions
In contrast to MSSA, MRSA spa types have a predominantly regional distribution in Europe. This finding is indicative of the selection and spread of a limited number of clones within health care networks, suggesting that control efforts aimed at interrupting the spread within and between health care institutions may not only be feasible but ultimately successful and should therefore be strongly encouraged. Please see later in the article for the Editors'' Summary 相似文献124.
Jeffrey A. Anderson Li-Hua Ping Oliver Dibben Cassandra B. Jabara Leslie Arney Laura Kincer Yuyang Tang Marcia Hobbs Irving Hoffman Peter Kazembe Corbin D. Jones Persephone Borrow Susan Fiscus Myron S. Cohen Ronald Swanstrom and the Center for HIV/AIDS Vaccine Immunology 《PLoS pathogens》2010,6(8)
HIV-1 is present in anatomical compartments and bodily fluids. Most transmissions occur through sexual acts, making virus in semen the proximal source in male donors. We find three distinct relationships in comparing viral RNA populations between blood and semen in men with chronic HIV-1 infection, and we propose that the viral populations in semen arise by multiple mechanisms including: direct import of virus, oligoclonal amplification within the seminal tract, or compartmentalization. In addition, we find significant enrichment of six out of nineteen cytokines and chemokines in semen of both HIV-infected and uninfected men, and another seven further enriched in infected individuals. The enrichment of cytokines involved in innate immunity in the seminal tract, complemented with chemokines in infected men, creates an environment conducive to T cell activation and viral replication. These studies define different relationships between virus in blood and semen that can significantly alter the composition of the viral population at the source that is most proximal to the transmitted virus. 相似文献
125.
Tourette Syndrome Association International Consortium for Genetics 《American journal of human genetics》2007,80(2):265-272
Tourette disorder (TD) is a neuropsychiatric disorder with a complex mode of inheritance and is characterized by multiple waxing and waning motor and phonic tics. This article reports the results of the largest genetic linkage study yet undertaken for TD. The sample analyzed includes 238 nuclear families yielding 304 "independent" sibling pairs and 18 separate multigenerational families, for a total of 2,040 individuals. A whole-genome screen with the use of 390 microsatellite markers was completed. Analyses were completed using two diagnostic classifications: (1) only individuals with TD were included as affected and (2) individuals with either TD or chronic-tic (CT) disorder were included as affected. Strong evidence of linkage was observed for a region on chromosome 2p (-log P = 4.42, P = 3.8 x 10(-5) in the analyses that included individuals with TD or CT disorder as affected. Results in several other regions also provide moderate evidence (-log P >2.0) of additional susceptibility loci for TD. 相似文献
126.
127.
Hawkey CJ Talley NJ Scheiman JM Jones RH Långström G Naesdal J Yeomans ND;NASA/SPACE author group 《Arthritis research & therapy》2007,9(1):R17
Non-steroidal anti-inflammatory drugs (NSAIDs), including selective cyclo-oxygenase-2 (COX-2) inhibitors, cause upper gastrointestinal
(GI) symptoms that are relieved by treatment with esomeprazole. We assessed esomeprazole for maintaining long-term relief
of such symptoms. Six hundred and ten patients with a chronic condition requiring anti-inflammatory therapy who achieved relief
of NSAID-associated symptoms of pain, discomfort, or burning in the upper abdomen during two previous studies were enrolled
and randomly assigned into two identical, multicentre, parallel-group, placebo-controlled studies of esomeprazole 20 mg or
40 mg treatment (NASA2 [Nexium Anti-inflammatory Symptom Amelioration] and SPACE2 [Symptom Prevention by Acid Control with
Esomeprazole] studies; ClinicalTrials.gov identifiers NCT00241514 and NCT00241553, respectively) performed at various rheumatology,
gastroenterology, and primary care clinics. Four hundred and twenty-six patients completed the 6-month treatment period. The
primary measure was the proportion of patients with relapse of upper GI symptoms, recorded in daily diary cards, after 6 months.
Relapse was defined as moderate-to-severe upper GI symptoms (a score of more than or equal to 3 on a 7-grade scale) for 3
days or more in any 7-day period. Esomeprazole was significantly more effective than placebo in maintaining relief of upper
GI symptoms throughout 6 months of treatment. Life-table estimates (95% confidence intervals) of the proportion of patients
with relapse at 6 months (pooled population) were placebo, 39.1% (32.2% to 46.0%); esomeprazole 20 mg, 29.3% (22.3% to 36.2%)
(p = 0.006 versus placebo); and esomeprazole 40 mg, 26.1% (19.4% to 32.9%) (p = 0.001 versus placebo). Patients on either non-selective NSAIDs or selective COX-2 inhibitors appeared to benefit. The frequency
of adverse events was similar in the three groups. Esomeprazole maintains relief of NSAID-associated upper GI symptoms in
patients taking continuous NSAIDs, including selective COX-2 inhibitors. 相似文献
128.
T. Nguyen-Dumont M. Mahmoodi F. Hammet T. Tran H. Tsimiklis Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer G.G. Giles J.L. Hopper Australian Breast Cancer Family Registry M.C. Southey D.J. Park 《Analytical biochemistry》2015
Many genetic epidemiology resources have collected dried blood spots (predominantly as Guthrie Cards) as an economical and efficient means of archiving sources of DNA, conferring great value to genetic screening methods that are compatible with this medium. We applied Hi-Plex to screen the breast cancer predisposition gene PALB2 in 93 Guthrie Card-derived DNA specimens previously characterized for PALB2 genetic variants via DNA derived from lymphoblastoid cell lines, whole blood, and buffy coat. Of the 93 archival Guthrie Card-derived DNAs, 92 (99%) were processed successfully and sequenced using approximately half of a MiSeq run. From these 92 DNAs, all 59 known variants were detected and no false-positive variant calls were yielded. Fully 98.13% of amplicons (5417/5520) were represented within 15-fold of the median coverage (2786 reads), and 99.98% of amplicons (5519/5520) were represented at a depth of 10 read-pairs or greater. With Hi-Plex, we show for the first time that a High-Plex amplicon-based massively parallel sequencing (MPS) system can be applied effectively to DNA prepared from dried blood spot archival specimens and, as such, can dramatically increase the scopes of both method and resource. 相似文献
129.
Elena Ciani Emiliano Lasagna Mariasilvia D’Andrea Ingrid Alloggio Fabio Marroni Simone Ceccobelli Juan V. Delgado Bermejo Francesca M. Sarti James Kijas Johannes A. Lenstra Fabio Pilla the International Sheep Genomics Consortium 《遗传、选种与进化》2015,47(1)
Background
Merino and Merino-derived sheep breeds have been widely distributed across the world, both as purebred and admixed populations. They represent an economically and historically important genetic resource which over time has been used as the basis for the development of new breeds. In order to examine the genetic influence of Merino in the context of a global collection of domestic sheep breeds, we analyzed genotype data that were obtained with the OvineSNP50 BeadChip (Illumina) for 671 individuals from 37 populations, including a subset of breeds from the Sheep HapMap dataset.Results
Based on a multi-dimensional scaling analysis, we highlighted four main clusters in this dataset, which corresponded to wild sheep, mouflon, primitive North European breeds and modern sheep (including Merino), respectively. The neighbor-network analysis further differentiated North-European and Mediterranean domestic breeds, with subclusters of Merino and Merino-derived breeds, other Spanish breeds and other Italian breeds. Model-based clustering, migration analysis and haplotype sharing indicated that genetic exchange occurred between archaic populations and also that a more recent Merino-mediated gene flow to several Merino-derived populations around the world took place. The close relationship between Spanish Merino and other Spanish breeds was consistent with an Iberian origin for the Merino breed, with possible earlier contributions from other Mediterranean stocks. The Merino populations from Australia, New Zealand and China were clearly separated from their European ancestors. We observed a genetic substructuring in the Spanish Merino population, which reflects recent herd management practices.Conclusions
Our data suggest that intensive gene flow, founder effects and geographic isolation are the main factors that determined the genetic makeup of current Merino and Merino-derived breeds. To explain how the current Merino and Merino-derived breeds were obtained, we propose a scenario that includes several consecutive migrations of sheep populations that may serve as working hypotheses for subsequent studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12711-015-0139-z) contains supplementary material, which is available to authorized users. 相似文献130.
Lisa Langsetmo Tuan V. Nguyen Nguyen D. Nguyen Christopher S. Kovacs Jerilynn C. Prior Jacqueline R. Center Suzanne Morin Robert G. Josse Jonathan D. Adachi David A. Hanley John A. Eisman the Canadian Multicentre Osteoporosis Study Research Group 《CMAJ》2011,183(2):E107-E114