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101.
Haixian Zhan Guangrong Li Xiaojun Zhang Xin Li Huijuan Guo Wenping Gong Juqing Jia Linyi Qiao Yongkang Ren Zujun Yang Zhijian Chang 《PloS one》2014,9(11)
Powdery mildew (PM) is a very destructive disease of wheat (Triticum aestivum L.). Wheat-Thinopyrum ponticum introgression line CH7086 was shown to possess powdery mildew resistance possibly originating from Th. ponticum. Genomic in situ hybridization and molecular characterization of the alien introgression failed to identify alien chromatin. To study the genetics of resistance, CH7086 was crossed with susceptible genotypes. Segregation in F2 populations and F2:3 lines tested with Chinese Bgt race E09 under controlled conditions indicated that CH7086 carries a single dominant gene for powdery mildew resistance. Fourteen SSR and EST-PCR markers linked with the locus were identified. The genetic distances between the locus and the two flanking markers were 1.5 and 3.2 cM, respectively. Based on the locations of the markers by nullisomic-tetrasomic and deletion lines of ‘Chinese Spring’, the resistance gene was located in deletion bin 2BL-0.89-1.00. Conserved orthologous marker analysis indicated that the genomic region flanking the resistance gene has a high level of collinearity to that of rice chromosome 4 and Brachypodium chromosome 5. Both resistance specificities and tests of allelism suggested the resistance gene in CH7086 was different from previously reported powdery mildew resistance genes on 2BL, and the gene was provisionally designated PmCH86. Molecular analysis of PmCH86 compared with other genes for resistance to Bgt in the 2BL-0.89-1.00 region suggested that PmCH86 may be a new PM resistance gene, and it was therefore designated as Pm51. The closely linked flanking markers could be useful in exploiting this putative wheat-Thinopyrum translocation line for rapid transfer of Pm51 to wheat breeding programs. 相似文献
102.
103.
为阐释不同污染程度下城市绿化植物吸滞PM2.5机理、解析污染物来源,应用气溶胶再发生器定量测定长沙市常见的2种园林绿化树种(桂花和香樟)植物叶片PM2.5吸附量,同时应用原子力显微镜(AFM)观察了不同污染区(交通区、文教区、清洁区)植被的叶表面微形态特征,使用离子色谱仪测定样品中水溶性离子含量.结果表明: 污染程度与植物叶表面PM2.5吸附量呈正相关,不同植物单位叶面积PM2.5吸附量全年均值表现为交通区(0.56±0.04 μg·cm-2)>文教区(0.48±0.06 μg·cm-2)>清洁区(0.33±0.02 μg·cm-2),植物单位叶面积PM2.5吸附量季节变化为冬季(0.70±0.10 μg·cm-2)>春季(0.43±0.14 μg·cm-2)>秋季(0.39±0.12 μg·cm-2)>夏季(0.31±0.09 μg·cm-2),桂花的单位叶面积PM2.5吸附量大于香樟;污染程度轻的区域的植物叶片比较光滑,污染程度重的区域的叶片较粗糙,植物粗糙度排序为交通区(195.45±16.09 nm)>文教区(176.99±8.45 nm)>清洁区(131.88±12.98 nm);不同污染程度地区PM2.5离子含量均表现为冬季最大,其次是春季和秋季,夏季最低;3个污染区PM2.5离子成分均以Na+、NH4+、Cl-和Br-这4种离子为主,不同程度污染区PM2.5污染均以移动源污染为主. 相似文献
104.
W S Cook S Jain Y Jia W Q Cao A V Yeldandi J K Reddy M S Rao 《Experimental cell research》2001,268(1):70-76
Mice deficient in fatty acyl-CoA oxidase (AOX(-/-)), the first enzyme of the peroxisomal beta-oxidation system, develop specific morphological and molecular changes in the liver characterized by microvesicular fatty change, increased mitosis, spontaneous peroxisome proliferation, increased mRNA and protein levels of genes regulated by peroxisome proliferator-activated receptor alpha (PPARalpha), and hepatocellular carcinoma. Based on these findings it is proposed that substrates for AOX function as ligands for PPARalpha. In this study we examined the sequential changes in morphology and gene expression in the liver of wild-type and AOX(-/-) mice at Embryonic Day 17.5, and during postnatal development up to 2 months of age. In AOX(-/-) mice high levels of expression of PPARalpha-responsive genes in the liver commenced on the day of birth and persisted throughout the postnatal period. We found no indication of PPARalpha activation in the livers of AOX(-/-) mice at embryonic age E17.5. In AOX(-/-) mice microvesicular fatty change in liver cells was evident at 7 days. At 2 months of age livers showed extensive steatosis and the presence in the periportal areas of clusters of hepatocytes with abundant granular eosinophilic cytoplasm rich in peroxisomes. These results suggest that the biological ligands for PPARalpha vis a vis substrates for AOX either are not functional in fetal liver or do not cross the placental barrier during the fetal development and that postnatally they are likely derived from milk and diet. 相似文献
105.
Shi Q Luo S Jin H Cai J Jia H Feng L Lu X 《Applied microbiology and biotechnology》2012,94(2):479-486
We successfully differentiated human adipose tissue-derived mesenchymal stem cells (haMSCs) into insulin-producing cells (IPCs)
in vitro and did not use any insulin which might be absorbed by cells during in vitro culture. Expression of insulin gene
was massively increased by 28,000-fold at day 12 compared with haMSCs (P < 0.05). IPCs could secrete insulin after glucose was stimulated. The higher the concentration of glucose, the more production
of insulin was noted. We reported AFM images of IPCs for the first time. AFM images showed that the sizes of cells were similar
to each other, and all IPC surface had a porous structure in the cytoplasm area. In sugar-free group, the size of holes was
similar (diameter, 1,086.98 ± 156.70 nm; depth, 185.22 ± 52.14 nm). In higher sugar-stimulated group, there were more holes
with bigger diameter and smaller depth. (diameter, 3,183.65 ± 2,229.18 nm; depth 109.42 ± 56.26 nm, P < 0.05). We found that the hole diameter and depth could change with the concentration of glucose in media. Concurrently,
laser scanning confocal microscopy images indicated that cortical actin network beneath plasma membrane in IPCs was dense
and continuous. After glucose stimulation, we found the actin web depolymerized and became discontinuous in IPCs. We speculated
that diameter augmentation of holes located in the cytoplasm area in IPCs was one manifestation of excytosis increase. 相似文献
106.
Reproductive and Developmental Toxicity of Orally Administered Botanical Composition,UP446‐Part III: Effects on Fertility and Early Embryonic Development to Implantation in Sprague Dawley Rats 下载免费PDF全文
Mesfin Yimam Young‐Chul Lee Eu‐Jin Hyun Qi Jia 《Birth defects research. Part B, Developmental and reproductive toxicology》2015,104(4):166-176
In recent years, high prevalence of adverse effects associated to the use of traditional medicines during pregnancy is becoming alarming due to the self‐medication of oral supplements by expecting mothers without supervision. Many expectant mothers use alternative and complementary medicines as a supplement to conventional pregnancy management with an inherent belief of considering herbal remedies as harmless. To the contrary, herbal remedies could incur a potential teratogenic risk both to the child bearing mother and the developing fetuses when consumed before or at the time of gestation. Here, we describe the potential adverse effects of orally administered UP446, a standardized bioflavonoid composition from the roots of Scutellaria baicalensis and the heartwoods of Acacia catechu, on fertility and early embryonic development to implantation in Sprague Dawley rats at doses of 250, 500, and 1000 mg/kg. Besides body weight and food consumption, reproductive functions, sperm motility and morphology, estrus cycle, and fertility rate were monitored. There were no statistically significant differences in reproductive function in all UP446 treated groups in both genders. Test substance impacts on reproductive parameters were very minimal. Neither sperm motility nor morphology was affected as a result of oral UP446 administrations in males. There were no treatment‐related effects on estrus cycle stages in females. No significant changes in necropsy or histopathology were observed for all the groups. Therefore, the no observed adverse effect level (NOAEL) of UP446 was considered to be 1000 mg/kg, the highest dose tested, in both genders 相似文献
107.
The diagnostic potential of MPT63‐derived HLA‐A*0201‐restricted CD8+T‐cell epitopes for active pulmonary tuberculosis 下载免费PDF全文
Zhiliang Duan Dezhou Li Qingjun Jia Juanjuan Xu Xinyu Chen Zhigang Xu Huifang Liu Bokun Chen Jinsheng Wen 《Microbiology and immunology》2015,59(12):705-715
MPT63 protein is found only in Mycobacterium tuberculosis complex, including M. tuberculosis and M. bovis. Detection of MPT63‐specific IFN‐γ‐secreting T cells could be useful for the diagnosis of tuberculosis (TB) diseases. In the present study, the HLA‐A*0201 restriction of ten predicted MPT63‐derived CD8 + T‐cell epitopes was assessed on the basis of T2 cell line and HLA‐A*0201 transgenic mice. The diagnostic potential of immunogenic peptides in active pulmonary TB patients was evaluated using an IFN‐γ enzyme‐linked immunospot assay. It was found that five peptides bound to HLA‐A*0201 with high affinity, whereas the remaining peptides exhibited low affinity for HLA‐A*0201. Five immunogenic peptides (MPT6318–26, MPT6329–37, MPT6320–28, MPT635–14 and MPT6310–19) elicited large numbers of cytotoxic IFN‐γ‐secreting T cells in HLA‐A*0201 transgenic mice. Each of the five immunogenic peptides was recognized by peripheral blood mononuclear cells from 45% to 73% of 40 HLA‐A*0201 positive TB patients. The total diagnostic sensitivity of the five immunogenic peptides was higher than that of a T‐SPOT.TB assay (based on ESAT‐6 and CFP‐10) (93% versus 90%). It is noticeable that the diagnostic sensitivity of the combination of five immunogenic peptides and T‐SPOT.TB assay reached 100%. These MPT63‐derived HLA‐A*0201‐restricted CD8 + T‐cell epitopes would likely contribute to the immunological diagnosis of M. tuberculosis infection and may provide the components for designing an effective TB vaccine. 相似文献
108.
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110.
Sen Jia Thomas Lansdall-Welfare Saatviga Sudhahar Cynthia Carter Nello Cristianini 《PloS one》2016,11(2)
Feminist news media researchers have long contended that masculine news values shape journalists’ quotidian decisions about what is newsworthy. As a result, it is argued, topics and issues traditionally regarded as primarily of interest and relevance to women are routinely marginalised in the news, while men’s views and voices are given privileged space. When women do show up in the news, it is often as “eye candy,” thus reinforcing women’s value as sources of visual pleasure rather than residing in the content of their views. To date, evidence to support such claims has tended to be based on small-scale, manual analyses of news content. In this article, we report on findings from our large-scale, data-driven study of gender representation in online English language news media. We analysed both words and images so as to give a broader picture of how gender is represented in online news. The corpus of news content examined consists of 2,353,652 articles collected over a period of six months from more than 950 different news outlets. From this initial dataset, we extracted 2,171,239 references to named persons and 1,376,824 images resolving the gender of names and faces using automated computational methods. We found that males were represented more often than females in both images and text, but in proportions that changed across topics, news outlets and mode. Moreover, the proportion of females was consistently higher in images than in text, for virtually all topics and news outlets; women were more likely to be represented visually than they were mentioned as a news actor or source. Our large-scale, data-driven analysis offers important empirical evidence of macroscopic patterns in news content concerning the way men and women are represented. 相似文献