全文获取类型
收费全文 | 330篇 |
免费 | 22篇 |
出版年
2022年 | 9篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 13篇 |
2015年 | 18篇 |
2014年 | 8篇 |
2013年 | 20篇 |
2012年 | 20篇 |
2011年 | 23篇 |
2010年 | 12篇 |
2009年 | 11篇 |
2008年 | 15篇 |
2007年 | 20篇 |
2006年 | 7篇 |
2005年 | 15篇 |
2004年 | 9篇 |
2003年 | 5篇 |
2002年 | 11篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1996年 | 3篇 |
1994年 | 2篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 6篇 |
1989年 | 2篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1976年 | 2篇 |
1974年 | 4篇 |
1973年 | 8篇 |
1972年 | 5篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 2篇 |
1967年 | 4篇 |
1965年 | 2篇 |
1950年 | 1篇 |
排序方式: 共有352条查询结果,搜索用时 15 毫秒
111.
Shono M Shimizu I Aoyagi E Taniguchi T Takenaka H Ishikawa M Urata M Sannomiya K Tamaki K Harada N Nakaya Y Takayama T 《Bioscience, biotechnology, and biochemistry》2008,72(10):2761-2763
An abdominal fat accumulation complicated by high blood triglycerides is regarded as a risk factor of metabolic syndrome. Feeding powdered nacre, mother of pearl, from Pinctada maxima, resulted in reduced body weight, visceral fat amount, and blood triglyceride level without influencing the food intake, body length, or amount of muscular tissue, suggesting that nacre powder specifically could decrease visceral fat. 相似文献
112.
Suzuki K Yamaya Y Kanzawa N Chiba M Sera K Asano R 《Biological trace element research》2008,124(1):92-96
The aim of this study was to investigate the relationships between the bronchopneumonia and mean concentrations of those trace elements in bronchoalveolar lavage fluid (BALF). Twenty-nine dogs were included this study (17 healthy dogs and 12 dogs with respiratory disease). Each BALF sample had been obtained during bronchoscope examination by use of a standardized method. The concentrations of Al, Br, Ca, Cu, Fe, K, Ni, P, Si, Sr and Zn in BALF were measured by the particle-induced X-ray emission method. We found no relationship between the bronchopneumonia and the levels of elements in the BALF, except Ca, P and Zn. The dogs with respiratory disease were found to have a large amount of Ca and Zn, and a high Ca/P and Zn/Cu ratios in BALF compared to those without respiratory disease. 相似文献
113.
Daisuke Matsui Ken-ichi Fuhshuku Shingo Nagamori Momoko Takata Yasuhisa Asano 《Journal of industrial microbiology & biotechnology》2017,44(11):1503-1510
Limited information is available on α-amino-ε-caprolactam (ACL) racemase (ACLR), a pyridoxal 5′-phosphate-dependent enzyme that acts on ACL and α-amino acid amides. In the present study, eight bacterial strains with the ability to racemize α-amino-ε-caprolactam were isolated and one of them was identified as Ensifer sp. strain 23-3. The gene for ACLR from Ensifer sp. 23-3 was cloned and expressed in Escherichia coli. The recombinant ACLR was then purified to homogeneity from the E. coli transformant harboring the ACLR gene from Ensifer sp. 23-3, and its properties were characterized. This enzyme acted not only on ACL but also on α-amino-δ-valerolactam, α-amino-ω-octalactam, α-aminobutyric acid amide, and alanine amide. 相似文献
114.
H Takatsu H Tasaki H N Kim S Ueda M Tsutsui K Yamashita T Toyokawa Y Morimoto Y Nakashima T Adachi 《Biochemical and biophysical research communications》2001,285(1):84-91
Reactive oxygen species have been proposed to play important roles in atherosclerosis. To investigate the protective role of extracellular superoxide dismutase (EC-SOD), its inhibition of endothelial-cell-mediated LDL oxidation was examined. We constructed the recombinant adenovirus AxCAEC-SOD expressing human EC-SOD by CAG promoter. Infection of endothelial cells with AxCAEC-SOD resulted in EC-SOD protein secretion in a dose-dependent manner and a decrease of endothelial-cell-derived superoxide production. Moreover, it was proven to coexist with heparan sulfate by immunohistochemical staining. Endothelial-cell-mediated LDL oxidation enhanced by ferric-sodium EDTA was inhibited by 47% in TBARS formation by AxCAEC-SOD infection. In agarose gel electrophoresis, AxCAEC-SOD decreased the negative charge of oxidized LDL by 50% and suppressed fragmentation of apolipoprotein B. These results suggested that human EC-SOD localized in the extracellular space and reduced endothelial-cell-mediated LDL oxidation. In subendothelial space, EC-SOD bound on heparan sulfate might suppress LDL oxidation through reduction of superoxide anion. 相似文献
115.
Skarzynski DJ Shibaya M Tasaki Y Korzekwa A Murakami S Woclawek-Potocka I Majewska M Okuda K 《Reproductive biology》2007,7(1):3-15
Calf serum (CS) is a common supplement used in cell culture. It has been suggested that CS contains substances protecting cells against apoptosis. To examine whether a culture system including CS is appropriate for studying apoptosis in bovine luteal cells, we examined the influence of CS on the expression of Fas, bcl-2 and bax gene. Since progesterone (P(4)) is known to be an anti-apoptotic factor in bovine luteal cells, the present study was carried out to examine the P(4) effect on apoptosis. Bovine mid-luteal cells were exposed to Fas ligand (Fas L) in the presence or in the absence of P(4) antagonist (onapristone, OP) in a basal medium (BM) containing 5% CS (BM-CS) or BM containing 0.1% BSA (BM-BSA). Although Fas L alone, OP alone or Fas L plus OP did not show any cytotoxic effect on the cells cultured in BM-CS, administration of OP or OP in combination with Fas L resulted in the killing of 30% and 55% of the cells cultured in BM-BSA medium, respectively (p<0.05). Concomitantly, CS inhibited bax mRNA expression and stimulated bcl-2 expression in the cells (p<0.05). Moreover, in the cells cultured with BM-CS, Fas mRNA expression was smaller than that of cells incubated in BM-BSA medium (p<0.05). The overall results suggest that CS suppressed Fas-mediated cell death in cultured bovine luteal cells by promoting the ratio of bcl-2 to bax expression and by inhibiting Fas expression. Therefore, it may be suggested that CS contains such anti-apoptotic substances (growth factors) amplifying the cell survival pathways in the bovine corpus luteum (CL) in vitro. 相似文献
116.
117.
Inositol monophosphates from the mycelia ofPholiota nameko were analyzed by gas chromatography. Mycelia were found to contain inositol-1-phosphate and inositol-2-phosphate isomers
in a proportion of 7∶1, the amounts being 50 and 7.2 pmol/mg dry weight, respectively. We assume that inositol-2-phosphate
is a hydrolysis product of the phytase reaction with phosphatase. It was also found that the amount of inositol monophosphates
in the mycelia was affected by the concentration of inorganic phosphate in the medium. 相似文献
118.
119.
Akiko Obinata Kuniaki Takata Momoko Kawada Hiroshi Hirano Hiroyoshi Endo 《Experimental cell research》1982,138(1):135-145
Hydrocortisone, at a physiological concentration of 10?8 M, induces keratinization of chick embryonic tarsometatarsal skin in a chemically defined medium in 4 days [1]. The presence of 1–4% DMSO with hydrocortisone reversibly prevented this keratinization. DMSO suppressed the appearance of epidermal structural protein, which was preferentially induced by hydrocortisone. It also suppressed hydrocortisone-induced epidermal transglutaminase activity; which was presumably responsible for polymerization and decrease in solubility of epidermal protein in keratinization, and it suppressed increase of epidermal protein. When DMSO was added to differentiated skin or added concomitantly with a higher concentration of hydrocortisone, epidermal transglutaminase activity was suppressed. Electron microscopic studies showed that hydrocortisone induced tonofilament bundles and keratinized cells with cellular envelopes, which are all characterestic of α-type keratinization of chick embryonic skin [2], and that DMSO inhibited hydrocortisone induced keratinization and kept the epidermis in an undifferentiated state. Moreover, DMSO inhibited epidermal DNA synthesis and increase in thickness of the epidermis during culture of hydrocortisone-treated skin, indicating that it suppressed cell proliferation as well as cell differentiation. DMSO by itself at 1 or 2 % did not affect epidermal cell differentiation, but suppressed cell proliferation when compared with untreated control. 相似文献
120.
Using giant axons of squid, Doryteuthis, available in Hokkaido, Japan, it was shown that axons internally perfused with a dilute sodium salt solution undergo an abrupt transition from a resting to a depolarized state on addition of KCl to an external medium containing CaCl2. Under internal perfusion with a dilute solution of sodium or cesium salt, it was possible to induce abrupt transitions between the two (i.e., resting and depolarized) states of the membrane by changing the temperature. “Giant fluctuations” in the state of the axon membrane were demonstrated at and near the critical points of the axon membrane. These findings are interpreted as supporting the view that an abrupt change in the membrane potential and conductance is an electrochemical manifestation of a phase transition of the membrane macromolecules. 相似文献