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991.
Hamacher M  Meyer HE 《Proteomics》2005,5(2):334-336
More than 1200 attendees came together at the 3(rd) HUPO World Congess in Beijing, October 25-27, 2004. In numerous different sessions the wide range of proteomic areas became visible. The HUPO Brain Proteome Project (HUPO BPP) organized an evening session on October 23, presenting the first results of two pilot studies as well as the newest, very positive international development in this field. The rising importance became even more apparent in the plenary presentation of all HUPO initiatives and the following congress activities.  相似文献   
992.
Vector abundance is an important factor governing disease risk and is often employed when modelling disease transmission. The longevity of the aquatic stages of mosquitoes (Diptera: Culicidae) dictates the rate of production of adults and hence the intensity of disease transmission. We examined how temperature influences the survival of larval stages (larvae and pupae) of Anopheles gambiae Giles sensu stricto and subsequent adult production of this most efficient malaria vector. Groups of 30 mosquitoes were reared at constant temperatures (from 10 to 40 degrees C) from the first instar and observed until death or metamorphosis of the last individual. Larvae developed into adults at temperatures ranging from 16 to 34 degrees C. Larval survival was shortest (< 7 days) at 10-12 degrees C and 38-40 degrees C, and longest (> 30 days) at 14-20 degrees C. Within the temperature range at which adults were produced, larval mortality was highest at the upper range 30-32 degrees C, with death (rather than adult emergence) representing over 70% of the terminal events. The optimal survival temperatures were lower than the temperatures at which development was quickest, suggesting a critical relationship between temperature and the life cycle of the insect. These data provide fundamental information about An. gambiae s.s. adult productivity at different temperatures, which may facilitate the construction of process-based models of malaria risk in Africa and the development of early warning systems for epidemics.  相似文献   
993.
Current knowledge of flower visitors and pollination in the Oriental Region is summarised. Much less is known about pollination than seed dispersal and the coverage of habitats and taxa in the region is very uneven. The available evidence suggests that pollination in lowland forests is dominated by highly social bees (mainly Trigona and Apis species), with beetles probably the next most important group, followed by other bees and flies. In comparison with the better-studied Neotropics, large solitary bees, moths, Lepidoptera and vertebrates are relatively less important. These differences are greatest in the canopy of the lowland dipterocarp forests of Southeast Asia, where they probably reflect the unique temporal pattern of floral resource availability resulting from 'general flowering' at supra-annual intervals. Apis bees (but not Trigona species) are also important in most montane, subtropical and non-forest habitats. Apart from the figs (Ficus spp.), there are few well-documented examples of plant species visited by a single potential pollinator and most plant-pollinator relationships in the region appear to be relatively generalised. The small sizes of most pollinators and the absence of direct human exploitation probably make pollination mutualisms less vulnerable to failure as a result of human impacts than dispersal mutualisms, but more subtle impacts, as a result of altered gene flows, are likely to be widespread. On current evidence, pollination systems in the Oriental Region do not require any specific conservation action, but this review reinforces arguments for making the preservation (or restoration) of habitat connectivity the major focus of Oriental conservation.  相似文献   
994.
The Escherichia coli rpoS gene encodes an RNA polymerase sigma factor (sigma S or S) required for the expression of stationary-phase genes. In the first published rpoS sequence from E. coli K-12 codon 33 is given as CAG. However, several subsequent independent studies found the amber codon TAG at this position ( rpoSAm). Besides this amber codon, other codons such as TAT have also been found at this location in rpoS. Comparative genome analysis now leads us to propose TAG as the parental codon 33 in rpoS in E. coli K-12. Five different stocks of the strain W3110, which differ in the levels of S protein they express, were investigated. We sequenced the rpoS gene from these, and found a T at nucleotide position 97 in four out of the five stocks and a G at position 99 in three out of the five. W1485, a parental strain of W3110, and W3350, a derivative of W3110, are also rpoSAm mutants. Such rpoSAm mutants would be expected to show no RpoS activity. The retention of partial or intermediate S activity by suppressor-free rpoSAm mutants is therefore puzzling. We propose that a functional, N-terminally truncated, S (1–53S) can be translated from a Secondary Translation Initiation Region (STIR) located downstream of the amber codon 33. It has recently been reported that a fragment of RpoS (1–53S) that lacks the first 53 amino acids is functional when synthesized in vivo. Taken together, our results support the hypothesis that the original codon 33 of the rpoS gene in E. coli K-12 strains is the amber codon TAG.Communicated by W. Goebel  相似文献   
995.
鸟鹏颖  时磊 《四川动物》2022,41(1):42-51
趾长比是指动物不同趾长的比值,常被认为是早期雄激素或雌激素暴露的标记物之一.本文通过测量新疆敏麻蜥Eremias arguta 3个地理种群的雌雄成体各趾长并计算趾长比,探究不同地理种群趾长及趾长比的两性差异.结果表明,伊犁地区雄性后肢的第2趾显著大于雌性(P<0.05);富蕴县雄性前肢、后肢的第2、3、4、5趾长均显...  相似文献   
996.
We revise the four species of Kaszabister Mazur, 1972, one of which, Kaszabister barrigaisp. n., is described as new. The other species in the genus are Kaszabister rubellus (Erichson, 1834), Kaszabister ferrugineus (Kirsch, 1873) and Kaszabister carinatus (Lewis, 1888). The species are principally known from the subtropics of South America, with one in Central America. Lectotypes are designated for Kaszabister rubellus and Kaszabister ferrugineus, and a key is provided for all the species. Ants of the genus Solenopsis Westwood, mainly Solenopsis invicta Buren and Solenopsis saevissima (Smith), are documented as hosts of three of the four species.  相似文献   
997.
北京城市公园湿地的休憩吸引力评价   总被引:1,自引:0,他引:1  
以北京地区20个城市公园湿地为研究对象,从公园湿地的景观质量、区位条件、可达性3方面构建了城市公园湿地休憩吸引力评价指标体系,并基于层次分析法赋权的综合指数评价方法,对公园湿地的休憩吸引力进行评价,最后通过实地问卷调查数据对休憩吸引力评价结果进行验证,结果表明:具有高休憩吸引力的公园湿地依次为颐和园、奥林匹克公园、青龙湖公园、北海公园、圆明园、玉渊潭公园、十渡、金海湖风景区、陶然亭公园、野鸭湖湿地,稻香湖湿地和珍珠湖风景区的休憩吸引力最低,其余8个公园湿地休憩吸引力一般.休憩吸引力评价结果与实际调查数据相符,说明所建立的评价指标体系与评价方法是可行的.20个公园湿地按照其休憩吸引力可聚为4类,据此可制定不同的管理对策.通过城市公园湿地休憩吸引力评价,分析城市公园湿地景观在休闲游憩方面所发挥的作用,可以为城市湿地公园的优化与配置、提高人居环境质量、改善城市景观布局提供依据.  相似文献   
998.
The vegetation cover in Gadarif Region, Sudan, underwent drastic changes within the last 60 years because of the combined effect of anthropogenic and climatic factors. As a consequence, a large number of plant species are threatened or even became extinct, and vast areas are now deforested. The purpose of this study is to use the local knowledge as a tool to identify and describe patterns of vegetation changes associated with the introduction of mechanized rain‐fed agriculture in the southern Gadarif Region. Data were collected by interviewing 10 key informants and 41 large‐scale farmers. The results provided rich ethnobotanical knowledge and a clear historical perspective of vegetation changes including plant species which have disappeared, decreased and increased in the area. The main factors leading to changes in plant species composition and abundance were vegetation clearance, charcoal and firewood production, wood cuttings, grazing and recently herbicides application. Respondents acknowledged that grazing, duration of abandonment, length of cultivation period, amount and variability of rainfall, fire events and weed composition are the major factors determining succession on fallow land. Farmers showed interest to preserve some multi‐purpose woody species (e.g. Acacia senegal, Balanites aegyptiaca) in their land. Such species should be given priority in rehabilitation activities.  相似文献   
999.
Zhao H  Wang F  Wang J  Xie H  Guo J  Liu C  Wang L  Lu X  Bao Y  Wang G  Zhong R  Niu B  Zhang T 《Gene》2012,505(2):340-344
Protein-L-isoaspartate (D-aspartate) O-methyltransferase 1 (PCMT1) gene encodes for the protein repair enzyme L-isoaspartate (D-aspartate) O-methyltransferase (PIMT), which is known to protect certain neural cells from Bax-induced apoptosis. Previous study has shown that PCMT1 polymorphisms rs4552 and rs4816 of infant are associated with spina bifida in the Californian population. The association between maternal polymorphism and neural tube defects is still uncovered. A case-control study was conducted to investigate a possible association between maternal PCMT1 and NTDs in Lvliang high-risk area of Shanxi Province in China, using a high-resolution DNA melting analysis genotyping method. We found that increased risk for anencephaly in isolated NTDs compared with the normal control group was observed for the G (vs. A) allele (p=0.034, OR=1.896, 95% CI, 1.04-3.45) and genotypes GG+GA (p=0.025, OR=2.237, 95% CI, 1.09-4.57). Although the significance was lost after multiple comparison correction, the results implied that maternal polymorphisms in PCMT1 might be a potential genetic risk factor for isolated anencephaly in this Chinese population.  相似文献   
1000.
Zhang H  Wang J  Yi B  Zhao Y  Liu Y  Zhang K  Cai X  Sun J  Huang L  Liao Q 《Gene》2012,495(2):183-188
We investigated the relationship between BsmI/ApaI polymorphisms in vitamin D receptor gene and diabetic nephropathy in a Han Chinese population. PCR-restriction fragment length polymorphism was used to test the genotype and allele frequency of BsmI and ApaI polymorphisms in 304 patients with type 2 diabetes mellitus (DM group) and 100 control individuals (ND group). The DM group was further divided into DN0 (no diabetic nephropathy), DN1 (diabetes with small amount of albuminuria), DN2 (diabetes with large amount of albuminuria), L/NDN (late-onset DN after 5 years/no DN over the whole follow-up period of 5 years) and EDN (early-onset diabetic nephropathy occurring within first year) subgroup. We found that (1) genotype and allele frequency of BsmI polymorphism had significant difference between DM and ND group; BB+Bb genotype and B allele frequency were significantly higher in DN2 group than in ND and DN0 group; the ApaI polymorphism and allele frequency did not show any difference between DM and ND group; (2) BsmI BB+Bb genotype and B allele frequency were significantly higher in EDN group than in L/NDN group; (3) among patients with nephropathy, albumin excretion rate (AER) in 24-hour urine was significantly higher in those with BB+Bb phenotype than in those with bb phenotype (P<0.01), (4) unconditional logistic regression analysis showed that BsmI BB+Bb genotype was not only correlated with type 2 diabetic nephropathy, but also correlated with early-onset type 2 diabetic nephropathy. We conclude that the allele B (BB or Bb genotype) in vitamin D receptor gene is correlated with large amount albuminuria in the Han Chinese population with type 2 diabetes, and is probably a risk factor for early-onset diabetic nephropathy.  相似文献   
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