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121.
122.
Syuhei Nakao Miyuki Mabuchi Shenglan Wang Yoko Kogure Tadashi Shimizu Koichi Noguchi Akito Tanaka Yi Dai 《Bioorganic & medicinal chemistry letters》2017,27(14):3167-3172
A series of 31 resveratrol derivatives was designed, synthesized and evaluated for activation and inhibition of the TRPA1 channel. Most acted as activators and desensitizers of TRPA1 channels like resveratrol or allyl isothiocyanate (AITC). Compound 4z (HUHS029) exhibited higher inhibitory activity than resveratrol with an IC50 value of 16.1 μM. The activity of 4z on TRPA1 was confirmed in TRPA1-expressing HEK293 cells, as well as in rat dorsal root ganglia neurons by a whole cell patch clamp recording. Furthermore, pretreatment with 4z exhibited an analgesic effect on AITC-evoked TRPA1-related pain behavior in vivo. 相似文献
123.
124.
CYP98A6 from Lithospermum erythrorhizon encodes 4-coumaroyl-4'-hydroxyphenyllactic acid 3-hydroxylase involved in rosmarinic acid biosynthesis 总被引:3,自引:0,他引:3
Rosmarinic acid is the dominant hydroxycinnamic acid ester accumulated in Boraginaceae and Lamiaceae plants. A cytochrome P450 cDNA was isolated by differential display from cultured cells of Lithospermum erythrorhizon, and the gene product was designated CYP98A6 based on the deduced amino acid sequence. After expression in yeast, the P450 was shown to catalyze the 3-hydroxylation of 4-coumaroyl-4'-hydroxyphenyllactic acid, one of the final two steps leading to rosmarinic acid. The expression level of CYP98A6 is dramatically increased by addition of yeast extract or methyl jasmonate to L. erythrorhizon cells, and its expression pattern reflected the elicitor-induced change in rosmarinic acid production, indicating that CYP98A6 plays an important role in regulation of rosmarinic acid biosynthesis. 相似文献
125.
Detection of urovirulence factors in Escherichia coli by multiplex polymerase chain reaction 总被引:1,自引:0,他引:1
Shingo Yamamoto Akito Terai Kazuyo Yuri Hisao Kurazono Yoshifumi Takeda Osamu Yoshida 《FEMS immunology and medical microbiology》1995,12(2):85-90
Abstract Primers to amplify the genes encoding the virulence factors of uropathogenic Escherichia coli , such as pilus associated with pyelonephritis ( pap ), haemolysin ( hly ), aerobactin ( aer ) and cytotoxic necrotizing factor 1 ( cnf 1) genes, were designed. The above primers along with previously reported primers for S fimbriae ( sfa ) and afimbrial adhesin I ( afaI ) genes were combined to develop a multiplex polymerase chain reaction (PCR) for detection of the respective virulence factors and for the identification of uropathogenic E. coli . The multiplex PCR to detect pap, sfa, afa I, hly, aer and cnf 1 genes was highly specific and the sensitivity was found to be about 5 × 103 colony forming units of E. coli per ml. A total of 194 E. coli strains isolated from patients with simple acute cystitis were examined by the multiplex PCR and the results were in complete agreement with that obtained by DNA colony hybridization test. The multiplex PCR developed was, therefore, concluded to be a useful, sensitive and rapid assay system to identify uropathogenic E. coli . 相似文献
126.
Suguru Takatsuto Naoto Yazawa Nobuo Ikekawa Tetsuo Takematsu Yasutomo Takeuchi Masami Koguchi 《Phytochemistry》1983,22(11):2437-2441
The plant growth-promoting activities of brassinolide and brassinosteroids with different side chains were investigated by means of the Raphanus an 相似文献
127.
Shigeo Takagi Takao Yoshida Atsushi Ohya Katsuo Tsubata Hisae Sakata Kiyoshi T. Fujii Sadao Iizuka Buichi Tochigi Meijin Tochigi Akito Mochigi 《Prostaglandins & other lipid mediators》1982,23(4)
The present clinical trials revealed that 16,16-Dimethyl-trans-δ2-PGE1 methyl ester in the form of vaginal suppositories is highly effective in inducing mid-trimester termination of pregnancies. It also showed that prior treatment with laminaria and metreurynter may enhance the success rate while reducing the incidence and severity of side effects. It is easy and safe to use clinically, with minimal side effects, and in our series, revealed no deleterious effects on ensuing reproductive physiology. However, the definite mechanism involved in the action of this new analogue to cause myometrial contractions is still not completely understood, and requires further intensive investigation. 相似文献
128.
Effects of extracellular matrix components on the growth and differentiation of cultured rat hepatocytes 总被引:11,自引:0,他引:11
Norimasa Sawada Akito Tomomura Carol A. Sattler Gerald L. Sattler Hynda K. Kleinman Henry C. Pitot 《In vitro cellular & developmental biology. Plant》1987,23(4):267-273
Summary Some effects of culturing adult rat hepatocytes on each of four different substrates—laminin (LN), collagen type I (C-I),
collagen type IV (C-IV), and fibronectin (FN)—have been investigated under defined conditions. No differential effect on the
attachment of the cells to the various substrates was noted; however, the spreading of hepatocytes shortly after initial plating
was most strikingly enhanced by FN, whereas LN exhibited little or no such enhancement. The two collagen substrates enhanced
the spreading of hepatocytes more than did LN, but less than FN. The different substrates had no differential effect on the
induction of tyrosine aminotransferase by dexamethasone and glucagon for at least the first 10 d in culture. The longevity
of the hepatocytes was not changed significantly by any of the substrates, at least through the 14th d of culture. During
the culture periods the hepatocytes at high cell density were maintained as confluent monolayers, regardless of the substrate
on which they had been cultured. After 14 d of culture, γ-glutamyltranspeptidase activity was highest in cells cultured on
C-IV, and lowest in those on FN. DNA synthesis in cultured hepatocytes at a low cell density was highest in cells cultured
on FN, with decreasing levels of this parameter in cells cultured on C-IV, C-I, and LN, respectively. These results demonstrate
that specific components of the extracellular matrix modulate both differentiated functions and the replication of hepatocytes
cultured in serum-free medium.
This work was supported in part by grants (CA-07175, CA-09135, CA-22484) from the National Cancer Institute, Bethesda MD.
N. Sawada was supported by a Cancer Research Campaign Grant D (U.K.) from the International Union Against Cancer. 相似文献
129.
Tetrakis{(alpha,alpha,alpha,alpha-o-pivalamido)phenyl}porphinatoiron(II) with a bifunctional tail possessing an axially coordinated imidazolyl group and a protein attachable succinimidyl(glutamyl) group (FeP-GluSu) has been synthesized. It can efficiently react with the lysine residues of recombinant human serum albumin (rHSA), giving a new albumin-heme conjugate [rHSA(FeP-Glu)]. MALDI-TOFMS showed a distinct molecular ion peak at m/z 70 643, which indicates that three FeP-Glu molecules were covalently linked to the rHSA scaffold. The binding number of FeP-Glu is approximately three (mol/mol) and independent of the mixing ratio. The CD spectrum and Native PAGE revealed that the albumin structure remained unaltered after the covalent bonding of the hemes. This rHSA(FeP-Glu) conjugate can bind and release O2 reversibly under physiological conditions (pH 7.3, 37 degrees C) in the same manner as hemoglobin and myoglobin. The O2-adduct complex had a remarkably long lifetime (tau(1/2): 5 h). The O2-binding affinity [P(1/2)O2: 27 Torr] was identical to that of human red cells. Laser flash photolysis experiments gave the O2- and CO-association rate constants and suggested that there are two different geometries of the imidazole binding to the central ion. 相似文献
130.