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Anu Lipsanen Stefanie Flunkert Kristina Kuptsova Mikko Hiltunen Manfred Windisch Birgit Hutter-Paier Jukka Jolkkonen 《PloS one》2013,8(3)
Experimental studies have identified a complex link between neurodegeneration, β-amyloid (Aβ) and calcium homeostasis. Here we asked whether early phase β-amyloid pathology in transgenic hAPPSL mice exaggerates the ischemic lesion and remote secondary pathology in the thalamus, and whether a non-selective calcium channel blocker reduces these pathologies. Transgenic hAPPSL (n = 33) and non-transgenic (n = 30) male mice (4–5 months) were subjected to unilateral cortical photothrombosis and treated with the non-selective calcium channel blocker bepridil (50 mg/kg, p.o., once a day) or vehicle for 28 days, starting administration 2 days after the operation. Animals were then perfused for histological analysis of infarct size, Aβ and calcium accumulation in the thalamus. Cortical photothrombosis resulted in a small infarct, which was associated with atypical Aβ and calcium accumulation in the ipsilateral thalamus. Transgenic mice had significantly smaller infarct volumes than non-transgenic littermates (P<0.05) and ischemia-induced rodent Aβ accumulation in the thalamus was lower in transgenic mice compared to non-transgenic mice (P<0.01). Bepridil decreased calcium load in the thalamus (P<0.01). The present data suggest less pronounced primary and secondary pathology in hAPPSL transgenic mice after ischemic cortical injury. Bepridil particularly decreased calcium pathology in the thalamus following ischemia. 相似文献
4.
Lymphoid cell subclasses in rejecting renal allograft in the rat 总被引:4,自引:0,他引:4
We have quantitated the frequency of lymphoid cell subsets in rejecting renal allografts and in the spleen of the allograft recipient during drug-unmodified rejection in the rat. The number of inflammatory (white) cells in the graft was approximately similar to the number of white cells responding to the allograft in the recipient spleen. The inflammatory population of the graft consisted of lymphoid cells and mononuclear phagocytes, with increasing numbers of macrophages toward the end of rejection. Analysis of allograft cellular dispersates with monoclonal antibodies directed to the lymphoid cell subsets demonstrated that although the majority of allograft-infiltrating lymphocytes were T cells, a sizable B-cell proliferation and immunoglobulin synthesis was associated with the inflammatory response of rejection. Within the T-cell subset, the T suppressor/killer cells predominated in the graft whereas the predominant lymphoid cell subset responding to the allograft in the recipient spleen was the T helper cell. 相似文献
5.
In order to find a suitable reagent for extracting the muscarinic receptor from rat brain membranes 14 different detergents
were tested. Only the plant glycoside digitonin efficiently solubilized the receptor protein in its native form. At the same
time microviscosity of detergent micelles was determined by measuring the fluorescence polarization of a hydrophobic fluorescent
probe diphenylhexatriene incorporated into the micelles. In the case of digitonin the polarization value was close to the
corresponding value obtained for rat brain membrane fragments, while for the other detergents studied it remained considerably
lower. The results obtained indicate that the fluidity of detergent micelles may play an important role in retaining the active
conformation of the solubilized muscarinic receptor. 相似文献
6.
Extracelluar lipase activity was detected in a culture of Pseudomonas strain Ptm+ growing on hexachlorocyclohexane. Lipase activity was associated with growth of the bacterium and reached a peak at early idiophase (22 h). Following the lipase activity, bioemulsifier was produced, with maximum activity at mid-idiophase (32 h). The extracellular lipase is probably involved in the extracellular synthesis of the bioemulsifier in the culture broth. 相似文献
7.
A complete synthesis of 1-O-hexadecyl-2-O-N-(heptadec-8-cis-enyl)carbamyl-sn-glycero-3-Phosphocholine, a novel analog of phosphatidylcholine, has been described. Each step is simple to perform and gives the desired products in high yield. Also, some of the intermediates formed during the synthesis have been efficiently utilized to prepare 1-O-hexadecyl-2-O-oleyl-sn-glycero-3-phosphocholine, 1-O-hexadecyl-2-oleoyl-sn-glycero-3-phosphochloine and 3-O-hexadecyl-2-oeloyl-sn-glycero-1-phosphocholine. These phosphatidylcholine (PC) analogs are useful for studying the possible role of phospholipases in the capture and lyses of liposomes in vivo. 相似文献
8.
U Krause M Nink A Brauer I Huber A Velten H Lehnert J Beyer 《Hormones et métabolisme》1991,23(10):499-503
Following an intravenous injection of 100 micrograms hCRH a facial flushing can frequently be observed along with respiratory stimulation. Both effects can be mediated by a common transmitter. Serotonin is well known to produce facial flush as well as to modulate respiration. In order to clarify is serotonin is a common mediator for facial flush and respiratory stimulation after i.v. application of hCRH, we studied the time course of facial skin temperatures and respiratory stimulation after intravenous injection of 100 micrograms hCRH in 10 healthy subjects. Furthermore, we measured respiratory stimulation after i.v. administration of 100 micrograms hCRH in 10 healthy subjects pretreated with the serotonin antagonist cyproheptadine. Facial skin temperatures reached maximum levels 9 min after CRH administration and remained raised for more than 60 min. Respiratory stimulation occurred within the first minute after CRH administration and reached a maximum during the second minute, but could no longer be observed after 10 min. Serum serotonin levels did not change after CRH stimulation in doses up to 3 micrograms/kg body weight), and cyproheptadine did not abolish the respiratory stimulation effect of hCRH in a dosage sufficient to suppress CRH.-induced cortisol secretion. 相似文献
9.
Unnikrishnan Parayil Babu Velukutty Anu Gopinath 《Chemical Speciation and Bioavailability》2013,25(4):153-167
AbstractConcentrations of heavy metals (Cd, Co, Cr, Cu and Fe) in surface sediments and their partitioning behaviour between exchangeable, reducible (Fe-Mn oxide bound) and organic/residual phases of the sediments in a typical backwater system of Kerala, viz. the southern upstream part of Cochin Estuarine System (South India), have been studied. Spatial and temporal variations of trace metals are discussed with special reference to pH, dissolved oxygen, salinity, organic carbon and texture of sediment. Metal concentrations in the tide gated part of the estuary were found to be significantly higher when compared to metal concentrations reported from the unrestricted part of the Cochin estuarine system and also those from many of the unpolluted estuaries worldwide. The higher levels of heavy metals in the study area and their characteristic distribution and partitioning behaviour in the surficial sediments were attributed to the presence of a salinity barrier across the backwater system and also by the massive use of pesticides and chemical fertilizers in the vast area of agricultural land near the backwater system. 相似文献
10.
L R Gurley W D Spall J G Valdez J E London L A Dethloff B E Lehnert 《Analytical biochemistry》1988,172(2):465-478
A high-performance liquid chromatography method has been developed for fractionating the protein components of the lung's extracellular lining fluid, as sampled by bronchoalveolar lavage. With this method, 10 ml (or less) of rat bronchoalveolar lavage fluid (BALF) in phosphate-buffered saline can be quantitatively analyzed rapidly and reproducibly. This volume (25% of the lavage fluid volume from one rat using a standardized lavage technique) is made 0.2% with respect to trifluoroacetic acid (TFA) and pumped through a microBondapak C18 Radial-PAK HPLC column equilibrated with H2O/0.2% TFA. Six fractions are then eluted with a series of acetonitrile gradients and isocratic steps that progress from H2O/0.2% TFA to 65% CH3 CN/0.2% TFA. Following this, 5 additional fractions are eluted with methanol. All 11 fractions are detected by monitoring the column effluents at 206 nm and can be recovered by lyophilization since all the components of the HPLC solvent system are volatile. Nine of the 11 fractions were found to contain protein. Three of the fractions contained proteins common to the blood compartment. The largest fraction of these was albumin, followed by a fraction containing immunoglobulins. Six other protein fractions appeared to be derived from the cells of the lung inasmuch as they were not detected in plasma. Two fractions contained no protein or phospholipids, whereas the most hydrophobic protein fraction did contain phospholipids. A major phospholipid fraction containing no protein eluted early in the chromatogram and was not detectable at 206 nm. This HPLC procedure offers significant utility for identifying and quantifying alterations in several BALF constituents during the development and progression of environmentally induced lung diseases as well as other pulmonary disorders. 相似文献