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171.
Atsushi TSUKAMOTO Mami IIMURO Reiichiro SATO Jumpei YAMAZAKI Tomo INOMATA 《Experimental Animals》2015,64(2):139-145
Isoflurane is a representative inhalant anesthesia used in laboratory animals. However,
isoflurane mediates respiratory depression and adverse clinical reactions during
induction. In the present study, we established a novel balanced anesthesia method in mice
that combined isoflurane anesthesia with midazolam and butorphanol (MB). Thirty-four male
C57BL/6J mice received either isoflurane alone or isoflurane with an intra-peritoneal MB
premedication (3 mg/kg midazolam and 4 mg/kg butorphanol). The minimum alveolar
concentration (MAC) in each group was evaluated. Induction time and adverse clinical
reactions were recorded in each group. Core body temperature, heart rate, respiratory
rate, and oxygen saturation (SPO2) were assessed before and for 1 h after
induction. Premedication with MB achieved a significant reduction in MAC compared with
isoflurane monoanesthesia (isoflurane, 1.38 ± 0.15%; isoflurane with MB, 0.78 ± 0.10%;
P<0.05). Induction time was significantly shortened with MB
premedication, and adverse reactions such as excitement or incontinence were observed less
frequently. Furthermore, isoflurane anesthesia with MB premedication caused increase of
respiratory rates compared to isoflurane monoanesthesia. No significant decrease of
SPO2 was observed in MBI anesthesia, while a decrease in SPO2 was
apparent with isoflurane monoanesthesia (baseline, 98.3% ± 1.1; 10 min after induction,
91.8 ± 6.4%; P<0.05). In conclusion, premedication with MB was
effective for the mitigation of respiratory depression induced by isoflurane in mice, with
rapid induction and fewer adverse clinical reactions. 相似文献
172.
The enteric protozoan parasite Entamoeba histolytica uniquely possesses two isotypes of ICPs, a novel class of inhibitors for cysteine proteases. These two EhICPs showed a remarkable difference in the ability to inhibit cysteine protease (CP) 5, a well-established virulence determinant, whereas they equally inhibited CP1 and CP2. Immunofluorescence imaging and cellular fractionation showed that EhICP1 and EhICP2 are localized to distinct compartments. While EhICP1 is localized to the soluble cytosolic fraction, EhICP2 is targeted from lysosomes to phagosomes upon erythrocyte engulfment. Overexpression of either EhICP1 or EhICP2 caused reduction of intracellular CP activity, but not the amount of CP, and decrease in the secretion of all major CPs, suggesting that both EhICPs are involved in the trafficking and/or interference with the major CP activity. These data indicate that the two EhICPs, present in distinct subcellular compartments, negatively regulate CP secretion, and, thus, the virulence of this parasite. 相似文献
173.
Higashida H Salmina A Hashii M Yokoyama S Zhang JS Noda M Zhong ZG Jin D 《FEBS letters》2006,580(20):4857-4860
ADP-ribosyl cyclase activity in the crude membrane fraction of neuroblastomaxglioma NGPM1-27 hybrid cells was measured by monitoring [(3)H] cyclic ADP-ribose (cADPR) formation from [(3)H] NAD(+). Bradykinin (BK) at 100nM increased ADP-ribosyl cyclase activity by about 2.5-fold. Application of 300nM BK to living NGPM1-27 cells decreased NAD(+) to 78% of the prestimulation level at 30s. In contrast, intracellular cADPR concentrations were increased by 2-3-fold during the period from 30 to 120s after the same treatment. Our results suggest that cADPR is one of the second messengers downstream of B(2) BK receptors. 相似文献
174.
175.
Mami AG Ballesteros JR Fritz KI Kubin J Mishra OP Delivoria-Papadopoulos M 《Neurochemical research》2006,31(1):57-62
The present study tested the hypothesis that magnesium sulfate administration prior to hypoxia prevents hypoxia-induced increase
in Ca2+/Calmodulin-dependent-kinase (CaM Kinase) IV and Protein Tyrosine Kinase (PTK ) activities. Animals were randomly divided
into normoxic (Nx), hypoxic (Hx) and magnesium-pretreated hypoxic (Mg2+-Hx) groups. Cerebral hypoxia was confirmed biochemically by measuring ATP and phosphocreatine (PCr) levels. CaM Kinase IV
and PTK activities were determined in Nx, Hx and Mg2+-Hx newborn piglets. There was a significant difference between CaM kinase IV activity (pmoles/mg protein/min) in Nx (270 ± 49),
Mg2+-Hx (317 ± 82) and Hx (574 ± 41, P < 0.05 vs. Nx and Mg2+-Hx) groups. Similarly, there was a significant difference between Protein Tyrosine Kinase activity (pmoles/mg protein/h)
in normoxic (378 ± 68), Mg2+-Hx (455 ± 67) and Hx (922 ± 66, P < 0.05 vs. Nx and Mg2+-Hx ) groups. We conclude that magnesium sulfate administration prior to hypoxia prevents hypoxia-induced increase in CaM
Kinase IV and Protein Tyrosine Kinase activities. We propose that by blocking the NMDA receptor ion-channel mediated Ca2+-flux, magnesium sulfate administration inhibits the Ca2+/calmodulin-dependent activation of CaMKIV and prevents the generation of nitric oxide free radicals and the subsequent increase
in PTK activity. As a result, phosphorylation of CREB and Bcl-2 family of proteins is prevented leading to prevention of programmed
cell death. 相似文献
176.
Zhou J Ueda M Umemiya R Battsetseg B Boldbaatar D Xuan X Fujisaki K 《Insect biochemistry and molecular biology》2006,36(7):527-535
Proteins capable of selective and specific inhibition of cysteine protease have been identified as cystatins and are isolated from a variety of microbes and tissues of animals and plants. The physiological function of these proteins has been proposed to be the regulation of protein turnover and defense against pathogens as well as the balance of the host-parasite immune relationship. Genes encoding cystatins have been found in several species of ticks, but the function of cystatin in ticks is not understood. We cloned a gene encoding cystatin from tick H. longicornis and designated it as Hlcyst-2 (H. longicornis cystatin-2). Its full-length cDNA is 569 bp, and it encodes a putative 133 amino acid protein with an obvious signal peptide. Sequence analysis demonstrated that it has significant homology with the known cystatin. The recombinant protein was expressed in a GST-fused soluble form in Escherichia coli and purified by affinity chromatography. The inhibitory activity of the recombinant protein against papain, cathepsin L, and cathepsin B was identified by fluorogenic substrate analysis. Cystatin was mostly expressed in the tick midgut and hemocyte. Blood feeding induced significantly increased expression in the midgut. Real-time PCR confirmed that LPS-injected adult ticks expressed Hlcyst-2 1.6 more times than the PBS-injected control; Babesia gibsoni-infected larvae ticks expressed Hlcyst-2 1.8 more times than normal larvae ticks. The recombinant protein also showed a significant growth-inhibitory effect on Babesia bovis cultured in vitro. These results indicated this cystatin Hlcyst-2 is involved in tick innate immunity. 相似文献
177.
Hitoshi Hashimoto† Ryota Hashimoto†‡§ Norihito Shintani Kazuhiro Tanaka Akiko Yamamoto Michiyoshi Hatanaka Xiaohong Guo Yoshiko Morita Mamoru Tanida¶ Katsuya Nagai¶ Masatoshi Takeda†‡ Akemichi Baba 《Journal of neurochemistry》2009,110(2):595-602
Axonal degeneration is a key component of many neurodegenerative diseases. Injured axons undergo a program of self-destruction termed Wallerian degeneration that is an active, well-regulated process. The pathways leading to axon fragmentation are uncharacterized, but experiments with wld s mutant mice led to the discovery that over-expression of NMN adenylyltransferase 1 or treatment with NAD+ can inhibit axonal degeneration. In this study, we show that the purine nucleosides adenosine and guanosine, but not inosine, inhibit injury-induced axonal degeneration in cultured dorsal root ganglia neurons. Axons can be preserved by adding adenosine within 6 h of the axonal injury. The presence of adenosine was required continuously after the injury to maintain axonal protection. Together these results suggest that adenosine does not alter the neuronal response to injury, but instead inhibits a local axonal pathway necessary for the commitment and/or execution of the axon destructive program. 相似文献
178.
179.
Ryo Nakabayashi Makoto Kobayashi Keiko Yonekura-Sakakibara Mami Yamazaki Mariko Kitajima Hiromitsu Takayama 《Phytochemistry》2009,70(8):1017-1029
In order to conduct metabolomic studies in a model plant for genome research, such as Arabidopsis thaliana (Arabidopsis), it is a prerequisite to obtain structural information for the isolated metabolites from the plant of interest. In this study, we isolated metabolites of Arabidopsis in a relatively non-targeted way, aiming at the construction of metabolite standards and chemotaxonomic comparison. Anthocyanins (5 and 7) called A8 and A10 were isolated and their structures were elucidated as cyanidin 3-O-[2-O-(β-d-xylopyranosyl)-6-O-(4-O-(β-d-glucopyranosyl)-E-p-coumaroyl)-β-d-glucopyranoside]-5-O-[6-O-(malonyl)-β-d-glucopyranoside] and cyanidin 3-O-[2-O-(2-O-(E-sinapoyl)-β-d-xylopyranosyl)-6-O-(4-O-(β-d-glucopyranosyl)-E-p-coumaroyl)-β-d-glucopyranoside]-5-O-[β-d-glucopyranoside] from analyses of 1D NMR, 2D NMR (1H NMR, NOE, 13C NMR, HMBC and HMQC), HRFABMS, FT-ESI-MS and GC-TOF-MS data. In addition, 35 known compounds, including six anthocyanins, eight flavonols, one nucleoside, one indole glucosinolate, four phenylpropanoids and a derivative, together with three indoles, one carotenoid, one apocarotenoid, three galactolipids, two chlorophyll derivatives, one steroid, one hydrocarbon, and two dicarboxylic acids, were also isolated and identified from their spectroscopic data. 相似文献