全文获取类型
收费全文 | 943篇 |
免费 | 70篇 |
出版年
2022年 | 5篇 |
2021年 | 9篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 11篇 |
2016年 | 7篇 |
2015年 | 21篇 |
2014年 | 19篇 |
2013年 | 41篇 |
2012年 | 48篇 |
2011年 | 44篇 |
2010年 | 25篇 |
2009年 | 26篇 |
2008年 | 63篇 |
2007年 | 61篇 |
2006年 | 52篇 |
2005年 | 58篇 |
2004年 | 68篇 |
2003年 | 55篇 |
2002年 | 50篇 |
2001年 | 18篇 |
2000年 | 30篇 |
1999年 | 18篇 |
1998年 | 14篇 |
1997年 | 18篇 |
1996年 | 10篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 11篇 |
1992年 | 21篇 |
1991年 | 12篇 |
1990年 | 13篇 |
1989年 | 14篇 |
1988年 | 14篇 |
1987年 | 13篇 |
1986年 | 23篇 |
1985年 | 11篇 |
1984年 | 9篇 |
1983年 | 10篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1979年 | 7篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1969年 | 3篇 |
1968年 | 3篇 |
排序方式: 共有1013条查询结果,搜索用时 15 毫秒
991.
We have developed an indirect microhemagglutination test (IMHA) for detecting antibodies to Borrelia burgdorferi using formalin-fixed chicken erythrocytes sensitized with a sonicated extract of the bacteria. The specificity of IMHA for Lyme disease was compared with that of a conventional indirect immunoperoxidase technique (IP) using sera from the patients with syphilis, randomly-chosen outpatients unrelated to Lyme disease, and from normal individuals. The IMHA was more specific than IP, giving little cross-reaction with syphilis. The IMHA also gave little background reactions with the sera of individuals unrelated to Lyme disease or syphilis. Therefore, the IMHA could be a useful test for the serodiagnosis of Lyme disease. 相似文献
992.
The genetic diversity and population structure of Rhinogobius sp. BB, the fluvial landlocked endangered goby, were investigated and were compared with those of the closely related amphidromous Rhinogobius sp. MO at 11 microsatellite loci. Specimens of Rhinogobius sp. BB were collected from the Genka and Takae-A rivers, and those of Rhinogobius sp. MO were collected from the Genka and Suginda rivers in Okinawa Island. At 11 microsatellite loci, the two populations of Rhinogobius sp. BB showed lower variation than the two Rhinogobius sp. MO populations: the average number of alleles was 3.6 and 2.0 vs. 8.6 and 7.6, respectively; and the observed heterozygosity was 0.263 and 0.281 vs. 0.440 and 0.545, respectively. Pairwise Fst tests showed significant differences (P < 0.001) among the populations: Fst was 0.525 between the two Rhinogobius sp. BB populations, 0.079 between the two Rhinogobius sp. MO populations, and varied from 0.456 to 0.462 for comparisons among Rhinogobius sp. BB and MO. Nei’s genetic distance between the two Rhinogobius sp. BB populations is extremely large (0.604) compared with that between the two Rhinogobius sp. MO populations (0.126). The two populations of Rhinogobius sp. BB are genetically divergent, and they have extremely low genetic diversity. Therefore, the conservation of Rhinogobius sp. BB in Okinawa Island requires the assessment of each river’s population. 相似文献
993.
Masayuki Kohno Koji Ohara Tomohisa Horibe Koji Kawakami 《International journal of peptide research and therapeutics》2014,20(2):153-160
Semaphorin 3A (Sema3A), an axon guidance molecule, inhibits neurite outgrowth of sensory neurons. Recombinant Sema3A protein has also inhibited scratching behavior and improved skin inflammation in an atopic dermatitis model. In the present study, we investigated whether Sema3A-derived peptides could bind its receptor, neuropilin-1 (NRP1), to inhibit neurite outgrowth. Here, two candidate NRP1-binding (NPB) peptides, NPB7 and NPB15, were found to inhibit NGF-induced survival and neurite outgrowth of PC12 cells and rat primary neurons in serum-free medium. To investigate the preventive effect of the two NPB peptides in vivo, we assessed whether they could inhibit skin inflammation induced by repeated topical application of oxazolone in mice. NPB15 peptide, but not NPB7, inhibited ear swelling. The NPB15 peptide solution and Vaseline ointment groups showed slightly decreased epidermal nerve densities compared with controls. The combination of NPB15 peptide and Vaseline ointment increased the inhibitory effect of NPB15 peptide on epidermal nerve densities. These results suggest that Sema3A-derived peptides can bind to NRP1 and inhibit neurite outgrowth both in vitro and in vivo. Thus, these peptides may be potent candidates for the treatment of atopic dermatitis. 相似文献
994.
995.
The dose-response curves for acute radiation symptoms reported by atomic bomb survivors are compared by dose estimation method (the method used to calculate the transmission factor), shielding category, and city. Circular symmetry is also investigated. It is found that response rates for acute symptoms differ considerably by dose estimation method and shielding category even after controlling for both gamma and neutron exposure as well as for city, sex, and age at the time of the bomb. One explanation of these results is that the doses of survivors in Japanese type houses estimated by the nine parameter method are subject to less random measurement error, while doses of those survivors who were in the open and shielded by terrain, who were totally shielded by concrete buildings, and who were in factories are subject to especially large random errors. The degree to which systematic bias contributes to these differences could not be determined. These results have important implications for comparisons between cities since Nagasaki includes a far greater proportion of survivors in shielding categories showing weak dose-response relationships than does Hiroshima. The hypothesis that doses might be higher in the westerly direction in Hiroshima is not supported by acute effects analyses, but excess acute effects are found in the north of Hiroshima. 相似文献
996.
Yu Takahashi Yuji Hori Tomohisa Yamamoto Toshiki Urashima Yasunori Ohara Hideo Tanaka 《Bioscience reports》2015,35(3)
3D (three-dimensional) cultures are considered to be an effective method for toxicological studies; however, little evidence has been reported whether 3D cultures have an impact on hepatocellular physiology regarding lipid or glucose metabolism. In the present study, we conducted physiological characterization of hepatoma cell lines HepG2 and HepaRG cells cultured in 3D conditions using a hanging drop method to verify the effect of culture environment on cellular responses. Apo (Apolipoprotein)B as well as albumin secretion was augmented by 3D cultures. Expression of genes related to not only drug, but also glucose and lipid metabolism were significantly enhanced in 3D cultured HepaRG spheroids. Furthermore, mRNA levels of CYP (cytochrome P450) enzymes following exposure to corresponding inducers increased under the 3D condition. These data suggest that this simple 3D culture system without any special biomaterials can improve liver-specific characteristics including lipid metabolism. Considering that the system enables high-throughput assay, it may become a powerful tool for compound screening concerning hepatocellular responses in order to identify potential drugs. 相似文献
997.
Gastric lesions induced by aspirin increased the ulcer index and incidence with prolongation of fasting time. Aspirin decreased gastric mucus glycoprotein in both the corpus and antrum. However, the rate of decrease in mucus glycoprotein induced by aspirin differed according to feeding habits and the gastric region. Qualitative change in corpus mucus glycoprotein was induced by aspirin. 相似文献
998.
Interferon-gamma inhibits the action of B cell stimulatory factor (BSF)-1 on resting B cells 总被引:10,自引:0,他引:10
E M Rabin J J Mond J Ohara W E Paul 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(5):1573-1576
B cell stimulatory factor-1 (BSF-1) stimulates resting B cells to increase in volume and prepares these cells to enter the S phase in response to anti-IgM and other B cell mitogens. Interferon-gamma (IFN-gamma) blocks both the volume enlargement and preparation for DNA synthesis caused by BSF-1, although it has little effect on B cells already stimulated by BSF-1. The capacity of IFN-gamma to inhibit the action of BSF-1 on resting B cells suggests a mutual regulatory interaction between these two T cell-derived products. 相似文献
999.
The chromatographic conditions for separation of N,N′-bislysyl(?-N)adipamidine and N-lysyl(?-N)adipamidinic acid, which were the products of acid hydrolysis of proteins treated with adipimidate esters, from other amino acids on an amino acid analyzer were established including their ninhydrin color values. Kinetics of decomposition of these lysine derivatives under the conditions of total acid hydrolysis of protein are also reported. 相似文献
1000.