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41.
【目的】本试验从瘤胃中分离鉴定降解粗纤维产甲烷的厌氧真菌与甲烷菌共培养物,为深入探究甲烷菌对厌氧真菌代谢途径的影响及相关调节机制奠定基础。【方法】利用厌氧滚管技术从荷斯坦奶牛瘤胃内容物中分离厌氧真菌与甲烷菌共培养物,通过形态学观察和DAPI染色以及甲烷菌16S rRNA基因序列分析方法分别对厌氧真菌及甲烷菌进行鉴定。【结果】从荷斯坦奶牛瘤胃中共分离到28株厌氧真菌与甲烷菌共培养物。共培养物中的厌氧真菌均为单中心菌株,分别属于Piromyces,Neocallimastix和Caeomyces属,所占百分比为53.57%,42.86%及3.57%。甲烷菌16S rRNA基因序列分析结果表明,共培养物中的甲烷菌均为甲烷短杆菌。本研究共获得四种不同的厌氧真菌与甲烷菌组合,分别为Piromyces/类Methanobrevibacter olleyae菌株,Neocallimastix/类Methanobrevibacter olleyae菌株,Neocallimastix/类Methanobrevibacter thaueri菌株及Caecomyces/类Methanobrevibacter olleyae菌株,分别占总数的53.57%,39.29%,3.57%及3.57%。【结论】分离得到的28株厌氧真菌和甲烷菌共培养物中,占优势的为具有丰富丝状假根的厌氧真菌Piromyces和Neocallimastix以及类Methanobrevibacter olleyae属的甲烷短杆菌。本研究为进一步研究瘤胃内厌氧真菌与甲烷菌相互代谢关系奠定基础。 相似文献
42.
杂交水稻及其“三系”线粒体DNA的AP—PCR指纹图谱 总被引:22,自引:1,他引:22
为了研究水稻(Oryza sativa L.)细胞质雄性不育(CMS)与线粒体基因组的关系,应用AP-PCR 分析,用7 个任意单引物对6 种水稻品系线粒体DNA 进行了扩增。水稻线粒体DNA 的AP-PCR 产物可分为三种类型:(1)所有供试品系均能扩增的片段,它们代表了线粒体DNA 在进化上的保守性序列。有4 个引物检测到这类片段。(2)2 个以上水稻品系共同出现而在全部供试材料间存在差异的扩增片段,这类片段是检测水稻线粒体DNA多态性的主要来源。(3)一种细胞质类型所特有的扩增片段,从引物R2 和V5 的扩增产物中发现了这类片段,它们可能与CMS有关联。另外,WA型不育系珍汕97A 与其杂种之间在6 个引物的扩增图谱上均存在不同程度的差异,说明两者的线粒体DNA序列结构可能存在某种差别 相似文献
43.
Human serum albumin (HSA) is the major protein component of human plasma. To date, HSA for clinical uses is mostly produced
by fractionation of human whole blood, which is accompanied by a lot of limitations. To obtain long-term bioactive albumin,
we used hsa as a foreign gene and constructed a recombinant plasmid pJS700-HSA which carries a recombinant gene cotC-hsa under the control of cotC promoter. Plasmid pJS700-HSA was transformed into Bacillus subtilis by double cross-over and an amylase inactivated mutant was produced. After induction of spore formation, western blot and
fluorescence immunoassay were used to monitor HSA surface expression on spores. We estimated that HSA displayed on the spore
accounted for 0.135 % of the total spore proteins and about 0.023 fg HSA were exposed on the surface of each spore. Oral administration
to mice with spores displaying HSA implied that the recombinant spores may have potential ability to increase the serum albumin
level in vivo due to the resistant characters of spores. 相似文献
44.
hnRNP C and polypyrimidine tract-binding protein specifically interact with the pyrimidine-rich region within the 3'NTR of the HCV RNA genome 总被引:3,自引:0,他引:3
Gontarek RR Gutshall LL Herold KM Tsai J Sathe GM Mao J Prescott C Del Vecchio AM 《Nucleic acids research》1999,27(6):1457-1463
Like other members of the Flaviviridae family, the 3' non-translated region (NTR) of the hepatitis C virus (HCV) is believed to function in the initiation and regulation of viral RNA replication by interacting with components of the viral replicase complex. To inves-tigate the possibility that host components may also participate in this process, we used UV cross-linking assays to determine if any cellular proteins could bind specifically to the 3'NTR RNA. We demonstrate the specific interaction of two host proteins with the extensive pyrimidine-rich region within the HCV 3'NTR. One host protein migrates as a doublet with a molecular weight of 57 kDa and is immunoreactive with antisera specific for polypyrimidine tract-binding protein (PTB), and the other protein (35 kDa) is recognized by a monoclonal antibody specific for heterogeneous nuclear ribonucleoprotein C (hnRNP C). These results suggest that recognition of the large pyrimidine-rich region by PTB and hnRNP C may play a role in the initiation and/or regulation of HCV RNA replication. 相似文献
45.
Mao S Lee SJ Hwangbo H Kim YW Park KH Cha GS Park RD Kim KY 《Current microbiology》2006,53(5):358-364
A new antagonistic Burkholderia strain, designated MP-1 and producing antifungal activities against various filamentous plant pathogenic fungi, was isolated
from the rhizoshere in the Naju area. Cultural characteristic studies strongly suggested that this strain belongs to the genus
Burkholderia. The nucleotide sequence of the 16S rRNA gene (1491 pb) of strain MP-1 exhibited close similarity (99% to 100%) with other
Burkholderia 16S rRNA genes. Extraction of fermentation broth of Burkholderia sp. MP-1 and various separations and purification steps led to isolation of four pure active molecules. The chemical structure
of these four compounds—named phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid, and 4-hydroxyphenylacetate
methyl ester—was established on the basis on their gas chromatography–electron impact–mass spectrometry (GC-EI-MS) and trimethylsilation
GC-EI-MS data. The four isolated compounds inhibited filamentous fungal growth on potato dextrose agar medium supplemented
with 100 mg/L of phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid and 4-hydroxyphenylacetate methyl ester
individually. 相似文献
46.
Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells 总被引:7,自引:0,他引:7
Mao JW Wang LW Jacob T Sun XR Li H Zhu LY Li P Zhong P Nie SH Chen LX 《Cell research》2005,15(5):371-378
The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5‘-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells. 相似文献
47.
莲幼苗的胚根发育及其筛分子研究 总被引:2,自引:0,他引:2
报道了莲无初生根型幼苗的胚根发育过程,其胚根由分生组织转化成贮藏组织,致使胚根不突破种皮;莲幼苗初生维管系统中的筛分子为筛管分子。莲的子叶和胚根连为一体的特殊结构与其生活环境和系统演化密切相关。 相似文献
48.
ChaoChien Chang KeeChin Sia JiaFeng Chang ChiaMo Lin ChuenMao Yang ITa Lee Thi Thuy Tien Vo KuoYang Huang WeiNing Lin 《Journal of cellular and molecular medicine》2022,26(14):3850
Obesity is a world‐wide problem, especially the child obesity, with the complication of various metabolic diseases. Child obesity can be developed as early as the age between 2 and 6. The expansion of fat mass in child age includes both hyperplasia and hypertrophy of adipose tissue, suggesting the importance of proliferation and adipogenesis of preadipocytes. The changed composition of gut microbiota is associated with obesity, revealing the roles of lipopolysaccharide (LPS) on manipulating adipose tissue development. Studies suggest that LPS enters the circulation and acts as a pro‐inflammatory regulator to facilitate pathologies. Nevertheless, the underlying mechanisms behind LPS‐modulated obesity are yet clearly elucidated. This study showed that LPS enhanced the expression of cyclooxygenase‐2 (COX‐2), an inflammatory regulator of obesity, in preadipocytes. Pretreating preadipocytes with the scavenger of reactive oxygen species (ROS) or the inhibitors of NADPH oxidase or p42/p44 MAPK markedly decreased LPS‐stimulated gene expression of COX‐2 together with the phosphorylation of p47phox and p42/p44 MAPK, separately. LPS activated p42/p44 MAPK via NADPH oxidase‐dependent ROS accumulation in preadipocytes. Reduction of intracellular ROS or attenuation of p42/p44 MAPK activation both reduced LPS‐mediated COX‐2 expression and preadipocyte proliferation. Moreover, LPS‐induced preadipocyte proliferation and adipogenesis were abolished by the inhibition of COX‐2 or PEG2 receptors. Taken together, our results suggested that LPS enhanced the proliferation and adipogenesis of preadipocytes via NADPH oxidase/ROS/p42/p44 MAPK‐dependent COX‐2 expression. 相似文献
49.
50.
M W Wong C B Xia M L Chen C X Zhang P S Mao G Q Nei Y Hosaka 《Japanese journal of medical science & biology》1988,41(1):31-36
Molluscicidal activity of B-2 (sodium 2,5-dichloro-4-bromophenol; called as Phebrol and registered in WHO as OMS 3012) was evaluated in a laboratory and the field trials were performed in two different localities in Yueyang city, China, for control of Oncomelania hupensis. B-2 was effective against O. hupensis both in the laboratory and in the field. A dosage of 50 g/m2 in 10% granular form or 20 ml/m2 in 25% liquid form of B-2 would be recommendable as a standard mollusciciding dose for control of O. hupensis. 相似文献