全文获取类型
收费全文 | 542篇 |
免费 | 27篇 |
出版年
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 11篇 |
2015年 | 25篇 |
2014年 | 27篇 |
2013年 | 32篇 |
2012年 | 36篇 |
2011年 | 29篇 |
2010年 | 18篇 |
2009年 | 14篇 |
2008年 | 31篇 |
2007年 | 43篇 |
2006年 | 31篇 |
2005年 | 24篇 |
2004年 | 30篇 |
2003年 | 22篇 |
2002年 | 19篇 |
2001年 | 11篇 |
2000年 | 5篇 |
1999年 | 7篇 |
1998年 | 7篇 |
1997年 | 9篇 |
1996年 | 9篇 |
1995年 | 13篇 |
1994年 | 10篇 |
1993年 | 13篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 7篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有569条查询结果,搜索用时 17 毫秒
471.
472.
Tsukasa Sato Yasuhiko Midorikawa Takao Yamashita Akemi Araki F. Sendo 《Cancer immunology, immunotherapy : CII》1996,43(2):77-86
Effective treatment of a rat transplanted ascites tumor by i. p. injection of a streptococcal biological response modifier,
OK-432, was abrogated by selective in vivo depletion of neutrophils by a monoclonal antibody, RP-3. The mechanisms by which
neutrophils participate in the therapeutic action of OK-432 were studied with Winn’s assay using peritoneal exudate cells
periodically obtained from rats i. p. injected with this biological response modifier. Intraperitoneal resident macrophages
were first activated with OK-432, and within 3 h, tumor-inhibitory activity had moved to the early exuded neutrophils. However,
6 h after injection, exuded macrophages were the only cells involved in tumor inhibition. Considered together with other findings,
it is likely that, in this system, neutrophils may transmit information from resident macrophages to exuded inflammatory macrophages
in a series of responses induced by i. p. injection of OK-432.
Received: 29 April 1996 / Accepted: 27 July 1996 相似文献
473.
CS-670, a novel nonsteroidal anti-inflammatory drug, is a racemic prodrug. Plasma concentrations and urinary excretion of CS-670 and its metabolites were determined in experimental subjects after oral administration at a single 120 mg dose. CS-670 and four metabolites, the saturated ketone (M-A), unsaturated-alcohol (M-B), cis-alcohol (M-C), and trans-alcohol (M-D), were quantitated by GC-MS. The major metabolites in human plasma were M-B, M-C, and M-D and their terminal half-lives (t½) were 0.9, 2.6, and 1.2 h, respectively. The total recovery in the urine was 26% of the dose, but unchanged CS-670 accounted for less than 2% over a 48 h period. In addition, the absolute configurations of the metabolites were examined by HPLC after derivatization with chiral reagents. It was found that the configuration of the propionic acid moiety of the metabolites, M-B, M-C, and M-D, in human plasma, was rapidly inverted from (-)-(R) to the (+)-(S) configuration in stereoselective biotransformation. Furthermore, the configurations of the 1′- and 2′-carbons of M-C and M-D, were found to be (1′R,2′S) and (1′R,2′S), respectively. These results show that CS-670 is readily biotransformed by chiral inversion of the 2-arylpropionic acid moiety and stereoselective reduction of the α, β-unsaturated ketone moiety in humans. © 1996 Wiley-Liss, Inc. 相似文献
474.
S Nishibe M Ogawa A Murata K Nakamura T Hatanaka J Kambayashi G Kosaki 《Life sciences》1983,32(14):1613-1620
Acetylcholine and arachidonic acid induced catecholamine secretion from isolated bovine adrenal medullary cells. Protease inhibitors and calmodulin inhibitors inhibited catecholamine secretion induced by acetylcholine but did not inhibit the secretion induced by arachidonic acid. BW 755-C, a lipoxygenase inhibitor, inhibited catecholamine release induced by acetylcholine. These results suggest that a protease and calmodulin are involved in the successive reaction after stimulus-receptor coupling and arachidonic acid or its metabolites might be important in catecholamine secretion from bovine adrenal medullary cells. 相似文献
475.
S Oikawa S Imajo T Noguchi G Kosaki H Nakazato 《Biochemical and biophysical research communications》1987,144(2):634-642
The amino acid sequences of human carcinoembryonic antigen deduced from the cDNA sequences have been analysed. This antigen contains seven extracellular domains (previously recognized three highly repetitive domains are further divided into A and B subdomains each) which are strikingly homologous to each other and to immunoglobulin variable regions, poly-Ig receptor and Thy 1.1. The N-terminal domain lacks immunoglobulin-like fold but the other six domains have, suggesting that the CEA belongs to immunoglobulin superfamily. 相似文献
476.
Primary structure of nonspecific crossreacting antigen (NCA), a member of carcinoembryonic antigen (CEA) gene family, deduced from cDNA sequence 总被引:6,自引:0,他引:6
Y Tawaragi S Oikawa Y Matsuoka G Kosaki H Nakazato 《Biochemical and biophysical research communications》1988,150(1):89-96
A cDNA containing the entire coding region for a member of carcinoembryonic antigen (CEA) gene family has been cloned from cDNA library of HLC-1 cells by immunochemical screening with the antibody specific to nonspecific crossreacting antigen (NCA). The cDNA encodes a precursor form of a polypeptide consisting of a 34-residue signal sequence, a 108-residue N-terminal (N-) domain, a 178-residue domain (NCA-I domain) and a 24-residue domain rich in hydrophobic amino acids (M-domain). Each domain has a distinct but homologous amino acid sequence to that of the corresponding domain of CEA. Unlike the coding sequences, the 3'-untranslated sequences differ markedly in the NCA and CEA cDNAs facilitating the preparation of probes that will discriminate between nucleotide sequences for CEA and NCA. 相似文献
477.
Immuno-gold localization of IAA in leaf cells of Prunus persica at different stages of development 总被引:1,自引:0,他引:1
Subcellular localization of indole-3-acetic acid (IAA) in leaf cells of peach ( Prunus persica [L.] Batsch 'Hakuho') was investigated using imuno-gold electron microscopy. The distribution pattern of the gold particles, which detected IAA, changed as cells matured. The most prominent feature was the accumulation of the gold label in the chloroplasts and mitochondria of the parenchyma cells of opened leaves. Throughout the development, the cytosol, nuclei, and cell wall were labelled, although the level was low and no significant changes occurred. The density of colloidal gold at each stage of leaf development was well correlated with the analytical data obtained by high-performance liquid chromatography (HPLC). 相似文献
478.
M Okamoto M Okamoto H Nishimura A Kosaki S Kono G Inoue I Maeda M Kubota T Hayashi H Kuzuya 《Endocrinologia japonica》1991,38(4):421-427
Changes in insulin-stimulated glucose metabolism were studied in young and aged subjects, subjects with impaired glucose tolerance, and patients with NIDDM by means of the glucose clamp technique. The diabetic group includes obese and non-obese patients treated without insulin and non-obese patients treated with insulin. The glucose disposal rate (GDR) was decreased in aged subjects (5.8 +/- 0.4 mg/kg/min) compared with young controls (7.4 +/- 0.3 mg/kg/min). In patients with IGT, it was further decreased to 3.6 +/- 0.5 mg/kg/min, which was comparable to the rate in NIDDM without insulin treatment (3.3 +/- 0.4 mg/kg/min). There were no differences in the GDR between obese (3.0 +/- 0.3 mg/kg/min) and non-obese (3.4 +/- 0.6 mg/kg/min) diabetic patients. In insulin-treated diabetic patients, GDR ranged widely, but the mean value was partially normalized (5.2 +/- 0.9 mg/kg/min). In the diabetic group, no correlation was observed between fasting blood glucose and GDR. These results suggest that in the course of developing NIDDM, a decrease in insulin-stimulated glucose uptake precedes a rise in fasting blood glucose. Thus, as previously reported for Caucasian NIDDM patients, resistance to insulin-stimulated glucose uptake may be one of the basic defects in Japanese patients with NIDDM. The degree of glycemia, however, is not directly related to the magnitude of the defect in insulin action. 相似文献
479.
Sakamoto Masahiro; Sanada Yasuharu; Tagiri Akemi; Murakami Taka; Ohashi Yuko; Matsuoka Makoto 《Plant & cell physiology》1991,32(3):385-393
The gene for the light-harvesting chlorophyll a/b binding proteinfrom rice was cloned and se-quenced. The clone contains a 798-bpcoding sequence, which is identical to that of a cDNA for typeI LHCPII (Matsuoka 1990), and its 5'- and 3'-flanking regions.The coding region of this gene is not interrupted by interveningsequences, as reported for type I genes from other plants. Inthe 5'-flanking region, typical TATA and CAAT boxes are located30 and 92 bp upstream from the capping site (positions 30and 92), respectively. A putative phytochrome-responsiveelement (AAGATAAGG) is located at position 65 betweenthe TATA and CAAT boxes. Comparison of sequences in the 5'-flankingregions between this gene and genes for LHCPII from other gramineousplants indicates that the rice sequence has no apparent homologyto that of wheat. However, the rice sequence is highly homologousto the maize sequence, not only around the TATA and CAAT boxesbut also in regions further upstream. To investigate the promoter activity of the 5'-flanking regionof the gene, a chimeric gene was constructed by fusing the 5'-flankingregion to the coding sequence for ß-glucuronidase(GUS), and this chimeric gene was introduced into tobacco. Thehighest activity of GUS was observed in leaf tissue, indicatingthat the 5'-flanking region of the gene can act as a promoterin an organ-specific manner in tobacco. Histochemical analysisin situ was also performed to determine where GUS activity wasexpressed. The highest activity was found in leaf mesophyllcells. High activity was also observed in the vascular systemof stems and petioles, and low activity was found in root tissue. (Received August 20, 1990; Accepted January 21, 1991) 相似文献
480.