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11.
12.
Endothelin-3 is a novel neuropeptide: isolation and sequence determination of endothelin-1 and endothelin-3 in porcine brain 总被引:4,自引:0,他引:4
O Shinmi S Kimura T Sawamura Y Sugita T Yoshizawa Y Uchiyama M Yanagisawa K Goto T Masaki I Kanazawa 《Biochemical and biophysical research communications》1989,164(1):587-593
The molecular forms of endothelin (ET) related peptides were investigated in porcine brain by using high performance liquid chromatography coupled with three specific radioimmunoassays. ET-1 and its oxidized form were isolated and sequenced as in the case of porcine spinal cord. A very small amount of big ET-1 (1-39) and its C-terminal fragment (big ET-1 (22-39] were also detected. Furthermore, immunoreactive (ir)-ET-3 was isolated and sequenced; its partial primary structure was identical to that of human (rat) ET-3. The concentrations of ir-ET-1 and ir-ET-3 in porcine brain were 140 fmol/g tissue and 5 fmol/g tissue, respectively. These results indicate that besides ET-1, ET-3 is a novel neuropeptide in the central nervous system. 相似文献
13.
H Watanabe H Miyazaki M Kondoh Y Masuda S Kimura M Yanagisawa T Masaki K Murakami 《Biochemical and biophysical research communications》1989,161(3):1252-1259
Competitive displacement experiments of 125I-endothelin (ET)-1, -2, or -3 binding to chick cardiac membranes were performed with unlabeled ET-1, -2, -3, and sarafotoxin S6b (STX) as competitors. 125I-ET-1 and -2 binding was competitively inhibited by increasing concentrations of these unlabeled peptides in the same order; i.e. ET-2 greater than or equal to ET-1 greater than ET-3 greater than STX. In contrast, the order of potency in displacing 125I-ET-3 binding was ET-3 greater than ET-2 greater than or equal to ET-1 greater than STX. Affinity labeling of the membranes by cross-linking with 125I-ET-1 and -2 via disuccinimidyl tartarate yielded one major specific band with an apparent Mr = 53,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography. On the other hand, affinity labeling with 125I-ET-3 showed that two major and one minor bands of Mr = 34,000, 46,000, and 53,000, respectively, were specifically labeled. These results indicate the presence of two distinct types of ET receptors, one of which has higher affinity for ET-1 and -2 than ET-3 and the other is conversely ET-3-preferring. 相似文献
14.
Presence of endothelin-1 in porcine spinal cord: isolation and sequence determination 总被引:2,自引:0,他引:2
O Shinmi S Kimura T Yoshizawa T Sawamura Y Uchiyama Y Sugita I Kanazawa M Yanagisawa K Goto T Masaki 《Biochemical and biophysical research communications》1989,162(1):340-346
We investigated the molecular forms of endothelin (ET) related peptides in porcine spinal cord by high performance liquid chromatography coupled with radioimmunoassays using three antisera raised against ET-1 and C-terminal fragments of ET-1 and big ET-1. ET-1 and its oxidized form were isolated as major immunoreactive peptides and sequenced. Furthermore, immunoreactivities like ET-3 and big ET-1(22-39) (contents: less than 8% and less than 1% of ET-1, respectively) were detected based on their chromatographic retention times and characteristics of immunoreactivity to the antisera. Big ET-1 was only scarcely detected. Immunohistochemical study showed the presence of ET-1-like immunoreactivity in motoneurons, dorsal horn neurons and dot- and fiber-like structures in the dorsal horn of lumbar spinal cord. These results indicate that ET-1 is present not only in endothelial cells but also in spinal cord, and that big ET-1 is converted into ET-1 in spinal cord by specific processing between Trp21-Val22. The data also indicate that ET-1 may act as a neuropeptide in the central nervous system. 相似文献
15.
Nobutaka Fujii Akira Otaka Susumu Funakoshi Toshihiro Watanabe Hiromitsu Arai Kiyoshi Bessho Haruaki Yajima 《Journal of Protein Chemistry》1988,7(2):151-156
Treatment of a mixture of Cys(R)(O) and Cys(R) with an acid was found to generate cystine in fairly good yields, when suitable R, R, and an acid were selected. An unsymmetrical cystine peptide was prepared by treatment of a mixture of Z(OMe)-Cys(R) (0)-Ala-NH2 (R=Acm or MBzl) and Z(OMe)-Cys(MBzl)-Gly-OBzl with TFA or 1 M TFMSA/TFA.3 Oxytocin was obtained in an excellent yield by TFA treatment of the protected peptide containing Cys(Acm)(0) and Cys(MBzl). Thus, formation of the disulfide bond was found feasible at the position of Cys(R) (0).The following abbreviations are used Boc
t-butyloxycarbonyl
- Z(OMe)
p-methoxybenzyloxycarbonyl
- MBzl
p-methoxybenzyl
- Acm
acetamidomethyl
- Bzl
benzyl
- Ad
l-adamantyl
- tBu
t-butyl
- TFA
trifluoroacetic acid
- TFMSA
trifluoromethanesulfonic acid
- TMSOTf
trimethylsilyl trifluoromethane sulfonate 相似文献
16.
The complete nucleotide sequence of the gene for batroxobin, a thrombin-like snake venom enzyme. 总被引:1,自引:0,他引:1
N Itoh N Tanaka I Funakoshi T Kawasaki S Mihashi I Yamashina 《Nucleic acids research》1988,16(21):10377-10378
17.
Hara Takayuki; Nagatani Akira; Yamaguchi Isomaro; Murofushi Noboru; Takahashi Nobutaka; Furuya Masaki 《Plant & cell physiology》1988,29(6):913-918
In the fern Lygodium japonicum, the effect of the exogenousapplication of two gibberellin methyl esters, gibberellin A4methyl ester (GA4Me) and gibberellin A20 methyl ester (GA20Me)on spore germination in the dark and uptake of GA4Me and GA20Meby spores was investigated. Tritiated GA4Me and GA20Me wereprepared and used as radioactive tracers. The activity of GA4Mewas more than 100-fold that of GA20Me for the induction of sporegermination. When treated for 24 h, the activity for inducingspore germination remained after removal of the gibberellinmethyl esters from the medium. The amount of GA4Me taken upby spores was more than three times that of GA20Me throughoutthe 24 h time course of treatment. The uptake of both gibberellinmethyl esters was proportional to the external concentrationfor the range of concentrations between 109 M and 106M. When treated with the tritiated gibberellin methyl estersat 106 M and 107 M for 24 h, most of the gibberellinmethyl esters taken up by the spores were not metabolized. Althoughthe uptake of the two gibberellin methyl esters differed by3- to 5- fold, their abilities to induce spore germination differedby more than 100-fold. Therefore, the difference in the activityof the two gibberellin methyl esters regarding the inductionof spore germination could not be explained solely by the differencein their uptake. (Received January 11, 1988; Accepted May 26, 1988) 相似文献
18.
Masaki Tateno 《Ecological Research》1988,3(3):267-277
Air-dried fresh and dead specimens ofPolygonum cuspidatum were incubated for 250 days in the laboratory, and the growth and turnover of microbial biomass-C in the organic matter were
studied. The biomass-C in the fresh leaf and fresh stem attained maximum levels on day 14 and day 7, respectively, and then
settled down to stable levels. In the dead leaf and dead stem, increase in biomass-C ceased by day 4 and the biomass-C levels
did not change thereafter. The turnover time of the biomass-C was estimated from the amount of biomass-C and the release rate
of CO2-C. The turnover was rapid in the early period of incubation. Then the turnover time became longer and after incubation for
70 days the values approached those in natural soils (longer than 16 days). During the incubation period, nitrogen was not
mineralized in any organic matter. In the dead leaf and dead stem, asymbiotic nitrogen fixation activity increased after incubation
for about 40 days and disappeared by the end of the incubation period, whereas nitrogen fixation was hardly detected in the
fresh leaf and fresh stem. 相似文献
19.
Masaki Fujimura Yasushi Miyake Kohhei Uotani Kazunori Kanamori Tamotsu Matsuda 《Prostaglandins & other lipid mediators》1988,35(3)
Effect of a thromboxane synthetase inhibitor (OKY-046) on bronchoconstriction induced by aerosol leukotriene C4 and histamine was studied in anesthetized, artificially ventilated guinea pigs in order to examine whether secondary release of thromboxane A2 is produced by aerosol leukotriene C4 or not. 0.01–1.0μg/ml of leukotriene C4 and 12.5–400μg/ml of histamine inhaled from ultrasonic nebulizer developed for small animals caused dose-dependent increase of pressure at airway opening (Pao) which is considered to be an index representing bronchial response. Pretreatment of the animals with intravenous OKY-046 (100mg/kg) significantly reduced the airway responses produced by inhalation of 0.1, 0.33 and 1.0μg/ml of leukotriene C4, while the pretreatment did not affect the histamine dose-response curve. Based on these findings and previous reports (6, 7), it is suggested that aerosol leukotriene C4 activates arachidonate cyclooxygenase pathway including thromboxane A2 synthesis and the released cyclooxygenase products have bronchodilating effect as a whole 相似文献
20.
T Masaki T Tanaka S Tsunasawa F Sakiyama M Soejima 《Bioscience, biotechnology, and biochemistry》1992,56(10):1604-1607
Z-Val-, Z-Pro-, Z-Leu-Leu-, and Z-Leu-Pro-lysinals and BZ-DL-lysinal were chemically synthesized and tested as novel inhibitors for Achromobacter protease I (API), a lysine-specific serine protease. Among the lysinal derivatives tested, Z-Val-lysinal was the most potent competitive inhibitor, its Ki being estimated as 6.5 nM in an esterolytic assay with Tos-Lys-OMe. In an amidolytic assay, Z-Leu-Leu-lysinal was the most potent inhibitor and the apparent mode of inhibition was non-competitive. The Kis of the other lysinal derivatives in both esterolytic and amidolytic assays were more than 10(3) times lower than that of leupeptin. Z-Val-lysinol, lacking the aldehyde group, was a poor competitive inhibitor. These results suggest that acyl-, acylaminoacyl-, and acylpeptidyllysinals function as a transition-state inhibitor for Achromobacter protease I. 相似文献