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1.

Background

Hypertension is one of the main risk factors of cardiovascular diseases. In Madagascar, studies on hypertension in urban and rural communities are scarce.

Objectives

The aim of this study was to determine the prevalence of hypertension and identify associated risk factors in adults living in a health and demographic system in Moramanga, Madagascar.

Methods

The study included people aged 15 years old and above living in a health and demographic system in Moramanga. A household census was performed in 2012 to enumerate the population in 3 communities in Moramanga. In addition to the questionnaire used in the initial census, a standardized questionnaire and blood pressure were taken twice after 5 and 10 minutes of rest. In urban areas, heights and weights were also measured to calculate the body mass index.

Results

There were 3621 and 4010 participants respectively in rural and urban areas. Prevalence of hypertension in rural population was 27.0% (IC95% [25.6–28.5]) and 29.7% (IC95% [28.3–31.1]) in urban population. Among hypertensive subjects, 1.7% (17/979) and 5.3% (64/1191) were on antihypertensive treatment for at least 1 month before the survey in rural and urban population, respectively. In rural areas, increasing age (65 years and older vs 18–25 years OR = 11.81, IC95% [7.79–18.07]), giving more than 3 positive responses to the usual risks factors of hypertension (OR = 1.67, IC95% [1.14–2.42]) and singles in comparison with married people (OR = 1.61, IC95% [1.20–2.17]) were associated to hypertension in a logistic regression model. In urban areas, increasing age (65 years and older vs 18–25 years OR = 37.54, IC95% [24.81–57.92]), more than 3 positive responses to the usual risks of hypertension (OR = 3.47, IC95% [2.58–4.67]) and obesity (OR = 2.45, IC95% [1.56–3.87]) were found as risk factors.

Conclusion

Hypertension is highly prevalent in rural areas although it is significantly less treated. As a result, a major epidemic of cardiovascular diseases is at risk in Madagascar’s progressively aging society.  相似文献   
2.
Investigatory behavior with novel, inanimate objects by two groups of four juvenile greater bushbabies (Otolemur garnettii) was examined in the laboratory. Substantial investigatory behavior was shown by all subjects. In the first study, subjects showed interest in a wide variety of nonfood stimulus objects. In the second, subjects displayed sustained interest in and investigation of non-food stimulus objects over three sessions. Bushbabies showed preferences for larger, more manipulable objects and variations in total contact over days. Individual differences were observed in the duration and types of contact with objects. These observations contradict earlier reports that prosimians show little interest in inanimate, non-food objects.  相似文献   
3.
Expression of the green fluorescent protein gene in conifer tissues   总被引:6,自引:2,他引:4  
The gene coding for the green fluorescent protein (GFP) from jellyfish was introduced into conifer tissues by microprojectile bombardment and its transient expression was detected. Two versions of the GFP gene, wild-type GFP and modified GFP with a cryptic intron removed, were directly compared for their expression in black spruce pollen. While the wild-type GFP gene resulted in a low level of expression, the modified GFP gene gave a dramatic increase in amount of expression (>100 times). The expression of GFP was detected in all the tissues tested : pollen, embryonal masses, suspension culture, and somatic embryos. Also, the GFP gene was introduced and expressed in three different conifer species (black spruce, white spruce, and white pine). The successful expression of the GFP gene in various tissues and different species suggests that it will be a useful reporter/marker gene for conifers.Abbreviations GUS -glucuronidase - NOS nopaline synthase - NPTII neomycin phosphotransferase - CaMV cauliflower mosaic virus Communicated by S. Gleddie  相似文献   
4.
5.
Since the beginning of taxonomy, species have been described based on morphology, but the advent of using semio-chemicals and genetics has led to the discovery of cryptic species (i.e. morphologically similar species). When a new cryptic species is described, earlier type specimens have to be re-evaluated, although this process can be challenging as only nondestructive methods ought to be used in order to preserve the integrity of the type specimens. Methods should allow comparison with recently collected specimens clustered based on chemical, ethological and/or genetic traits with old specimens (i.e. type specimens) where only morphological traits are available. Here we develop a method based on geometric morphometric analyses of wing shape for a taxonomically challenging group of bumblebees, the subgenus Alpinobombus Skorikov. We consider nine monophyletic taxa (including several cryptic species) to assess the accuracy of this method to discriminate the taxa based on their wing shape and then to attribute type specimens using a leave-one-out cross-validation procedure. We show that, for these bees, wing shape is taxon-specific, except for two sister taxa for which the species status is still debated. Moreover, for most of the taxa, type specimens were correctly attributed with high posterior probabilities of attribution, except for a few type specimens corresponding to the same two sister taxa where taxa delimitation based on wing shape was previously the subject of discussion. Our study highlights the potential of geometric morphometric analyses to help in the re-attribution of type specimens when the existence of cryptic species is revealed.  相似文献   
6.
We recently reported genomic regions associated with resistance to four wheat diseases and insensitivity to three Pyrenophora tritici-repentis toxins in an association mapping panel consisting of 81 diverse Canadian western spring wheat (Triticum aestivum L.) cultivars. Here, we report genomic regions and SNPs associated with days to heading, plant maturity, plant height, test weight (grain volume weight), grain yield, and grain protein content in the same population using genome-wide association studies (GWAS). The 81 spring wheat cultivars were evaluated for the above six traits across six environments and genotyped with 19,919 polymorphic SNPs and 14 gene-specific markers. Using mixed liner model and a threshold of p ≤ 3.1 × 10?4, we identified a total of 139 significant marker-trait associations that were mapped at 19 genomic regions on 11 chromosomes for heading (3 regions), maturity (2), plant height (3), test weight (3), grain yield (6), and grain protein (2). Each region consisted of clusters of markers ranging from 2 to 33 and individually explained from 4.5 to 26.1% of the phenotypic variation averaged over six environments. Some the genomic regions identified in the present study are novel, while others, such as the regions for grain protein on 1B, days to heading on 5A, plant height on 4B, and test weight on 7A, were located close to either known genes or QTLs reported in previous studies, but direct comparisons in some cases were challenging due to lack of common set of markers and reliable physical positions among the different studies. Results from this study provide additional information to wheat researchers developing improved spring wheat cultivars.  相似文献   
7.
8.
Transforming growth factor-β (TGF-β) signaling has been prominently implicated in the pathogenesis of vascular remodeling, especially the initiation and progression of flow-induced vascular remodeling. Smooth muscle cells (SMCs) are the principal resident cells in arterial wall and are critical for arterial remodeling. However, the role of TGF-β signaling in SMC for flow-induced vascular remodeling remains unknown. Therefore, the goal of our study was to determine the effect of TGF-β pathway in SMC for vascular remodeling, by using a genetical smooth muscle-specific (SM-specific) TGF-β type II receptor (Tgfbr2) deletion mice model. Mice deficient in the expression of Tgfbr2 (MyhCre.Tgfbr2f/f) and their corresponding wild-type background mice (MyhCre.Tgfbr2WT/WT) underwent partial ligation of left common carotid artery for 1, 2, or 4 weeks. Then the carotid arteries were harvested and indicated that the disruption of Tgfbr2 in SMC provided prominent inhibition of vascular remodeling. And the thickening of carotid media, proliferation of SMC, infiltration of macrophage, and expression of matrix metalloproteinase (MMP) were all significantly attenuated in Tgfbr2 disruption mice. Our study demonstrated, for the first time, that the TGF-β signaling in SMC plays an essential role in flow-induced vascular remodeling and disruption can prevent this process.  相似文献   
9.
Chikungunya virus (CHIKV) is a reemerging, ordinarily mosquito-transmitted, alphavirus that occasionally produces hemorrhagic manifestations, such as nose bleed and bleeding gums, in human patients. Interferon response factor 3 and 7 deficient (IRF3/7-/-) mice, which are deficient for interferon α/β responses, reliably develop hemorrhagic manifestations after CHIKV infection. Here we show that infectious virus was present in the oral cavity of CHIKV infected IRF3/7-/- mice, likely due to hemorrhagic lesions in the olfactory epithelium that allow egress of infected blood into the nasal, and subsequently, oral cavities. In addition, IRF3/7-/- mice were more susceptible to infection with CHIKV via intranasal and oral routes, with IRF3/7-/- mice also able to transmit virus mouse-to-mouse without an arthropod vector. Cynomolgus macaques often show bleeding gums after CHIKV infection, and analysis of saliva from several infected monkeys also revealed the presence of viral RNA and infectious virus. Furthermore, saliva samples collected from several acute CHIKV patients with hemorrhagic manifestations were found to contain viral RNA and infectious virus. Oral fluids can therefore be infectious during acute CHIKV infections, likely due to hemorrhagic manifestations in the oral/nasal cavities.  相似文献   
10.
The marine cave‐dwelling mysid Hemimysis margalefi is distributed over the whole Mediterranean Sea, which contrasts with the poor dispersal capabilities of this brooding species. In addition, underwater marine caves are a highly fragmented habitat which further promotes strong genetic structuring, therefore providing highly informative data on the levels of marine population connectivity across biogeographical regions. This study investigates how habitat and geography have shaped the connectivity network of this poor disperser over the entire Mediterranean Sea through the use of several mitochondrial and nuclear markers. Five deeply divergent lineages were observed among H. margalefi populations resulting from deep phylogeographical breaks, some dating back to the Oligo‐Miocene. Whether looking at the intralineage or interlineage levels, H. margalefi populations present a high genetic diversity and population structuring. This study suggests that the five distinct lineages observed in H. margalefi actually correspond to as many separate cryptic taxa. The nominal species, H. margalefi sensu stricto, corresponds to the westernmost lineage here surveyed from the Alboran Sea to southeastern Italy. Typical genetic breaks such as the Almeria‐Oran Front or the Siculo‐Tunisian Strait do not appear to be influential on the studied loci in H. margalefi sensu stricto. Instead, population structuring appears more complex and subtle than usually found for model species with a pelagic dispersal phase. The remaining four cryptic taxa are all found in the eastern basin, but incomplete lineage sorting is suspected and speciation might still be in process. Present‐day population structure of the different H. margalefi cryptic species appears to result from past vicariance events started in the Oligo‐Miocene and maintained by present‐day coastal topography, water circulation and habitat fragmentation.  相似文献   
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