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861.
The green alga Chlamydomonas reinhardtii is one of the most studied microalgae, which has the potential to be used as a model system to study lipid metabolism. Establishment of a method in this organism for rapid and simple measurement of neutral lipids is desirable. Fluorescent measurement of neural lipids by Nile Red staining has been widely used in various cell types including microalgae. However, a systematic study of Nile Red staining to measure neutral lipids in Chlamydomonas has not been reported. Here, we show that Nile Red staining is suitable for relative and absolute quantification of neutral lipids as well as for possible large-scale screening for mutants defective in lipid accumulation. We have compared and optimized the factors involved Nile Red staining including solvents, cell concentration, staining time, and Nile Red concentration. We determined that 5 % DMSO with 1 μg mL?1 Nile Red and 5–15-min time window after staining was optimal for measuring lipid content of cells within the range of 1 to 8?×?106 cells mL?1. The absolute quantification of neutral lipids could be achieved by standard addition method. In addition, we developed a protocol that could be potentially used for large-scale screening for cells with different lipid content. Thus, the work reported here provides timely needed techniques to facilitate Chlamydomonas to be used as a model organism for studying lipid metabolism for biodiesel production. 相似文献
862.
Elisha Guy Halder Sourav Acharya Shashank Carlson Dustin A. Kou Wenjun Kahrilas Peter J. Pandolfino John E. Patankar Neelesh A. 《Biomechanics and modeling in mechanobiology》2023,22(3):905-923
Biomechanics and Modeling in Mechanobiology - The esophagogastric junction (EGJ) is located at the distal end of the esophagus and acts as a valve allowing swallowed food to enter the stomach and... 相似文献
863.
864.
The corpora allata in adult Loreyi leafworms Leucania loreyi (Lepidoptera: Noctuidae) exhibit sexual dimorphism. The male possesses right and left corpora allata of about the same size. Each gland is composed of a cluster of approximately 40 semi-transparent, spherical, isolated cells held together by fine tracheae and nerve fibers. The largest cell diameter found in male glands was 203 pm. In contrast, the female gland cells and clusters are much smaller. The largest dimensions of one whole female gland cluster were 452 μm in length and 280 μm in width. Using bilateral and unilateral larval allatectomy, we confirmed that the adult isolated cell type glands develop ontogenetically from larval capsular type glands. Ultrastructural study re- vealed many similarities between the subcellular structures of the isolated cell type glands of L. loreyi and the more common capsular gland reported by others. These similarities include very large numbers of mitochondria, abun- dant whorled smooth endoplasmic reticulum, irregularly shaped nuclei, Golgi bodies, and free ribosomes. Compared with the corpora allata of 3- to 9-day-old adults, the glands of 1-day-old adults possessed much less smooth endoplasmic reticulum. The gland cells in females usually have more neurosecretory nerve endings, less-abundant stacked smooth endoplasmic reticulum, and less- defined interdigitations than the gland cells in males. © 1995 Wiley-Liss, Inc. 相似文献
865.
866.
867.
Rapid and efficient selection of recombinant site-directed mutants of Bradyrhizobium japonicum by colony hybridization 总被引:4,自引:0,他引:4
Abstract Due to the high incidence of spontaneous antibiotic resistance and slow growth of Bradyrhizobium japonicum strains, screening for site-directed mutants is cumbersome and time-consuming. A rapid method for selection of recombinant site-directed mutants of B. japonicum was developed. A kanamycin (Km) and a spectinomycin (Sp) cassette were each used to replace DNA fragments in the chromosome by homologous recombination. The primary new features of this method involve a simple plate selection for the antibiotic (Km or Sp) resistant mutants, then colony streaking, and lysis for DNA hybridization on a nitrocellulose filter enabling direct identification of the recombinant site-directed mutants. This method has permitted us to quickly and easily identify a large number of positive recombinant mutants from a large number of indicidual colonies. The procedure eliminates the need to first isolate genomic DNA from each mutant for Southern hybridization. All of the tested site-directed mutants from this method were confirmed to exhibit the expected mutant phenotype. 相似文献
868.
869.
Na Sun Fandong Meng Jie Zhao Xueqin Li Rongqing Li Jing Han Xin Chen Wanpeng Cheng Xiaoying Yang Yanbo Kou Kuiyang Zheng Jing Yang Takayuki Ikezoe 《International journal of biological sciences》2021,17(5):1302
Aurora-A kinase, a serine/threonine mitotic kinase involved in mitosis, is overexpressed in several human cancers. A recent study showed that Aurora-A mediates glucose metabolism via SOX8/FOXK1 in ovarian cancer. However, the roles of Aurora-A in metabolic diseases remain unclear. This study found that Aurka loss in the intestinal epithelium promoted age-induced obesity and enlargement of lipid droplets in parallel with an increase in infiltrated macrophages in the white adipocyte tissue (WAT) of male mice. Moreover, loss of Aurka induced the expression of lipid metabolism regulatory genes, including acetyl-coenzyme A carboxylase 1 (Acc1), in association with an increase in the levels of p-AKT in the intestinal epithelium as well as WAT. Blockade of AKT activation reduced the expression of lipid metabolism regulatory genes. In subsequent experiments, we found that the Firmicutes abundance and the levels of short-chain fatty acids (SCFAs) in the gut were dramatically increased in Aurkaf/+;VillinCre/+ mice compared with Aurkaf/+ mice. Additionally, propionate increased the phosphorylation of AKT in vitro. These observations indicated that Aurka loss in the intestinal epithelium contributed to gut microbiota dysbiosis and higher levels of SCFAs, especially propionate, leading to AKT activation and lipid metabolism regulatory gene expression, which in turn promoted age-induced obesity. 相似文献
870.
Ping-Chung Liu Kuo-Kau Lee Kah-Ching Yii Guang-Hsiung Kou Shiu-Nan Chen 《Current microbiology》1996,33(2):129-132
Outbreaks of high mortality among the cultured kuruma prawn Penaeus japonicus without overt gross signs occurred during August and December of 1994 in I-Lan, Taiwan. Eleven luminous bacterial strains
were isolated from the hepatopancreas of moribund prawns from five different farms by use of tryptic soy agar (TSA, supplemented
with 2% NaCl) and/or thiosulfate citrate bile salt sucrose (TCBS) agar. These strains, together with our two previously unpublished
isolates, were characterized and identified to be Vibrio harveyi in comparison with two ATCC Type strains and one strain previously isolated from the tiger prawn, P. monodon.
Received: 22 November 1995 / Accepted: 24 February 1996 相似文献