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171.
The binding of 3H-naltrexone, an opiate receptor antagonist, to membranes of discrete brain regions and spinal cord of 10 week old spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats was determined. The brain regions examined were hypothalamus, amygdala, hippocampus, corpus striatum, pons and medulla, midbrain and cortex. 3H-Naltrexone bound to membranes of brain regions and spinal cord at a single high affinity site with an apparent dissociation constant value of 3 nM. The highest density of 3H-naltrexone binding sites were in hippocampus and lowest in the cerebral cortex. The receptor density (Bmax value) and apparent dissociation constant (Kd value) values of 3H-naltrexone to bind to opiate receptors on the membranes of amygdala, hippocampus, corpus striatum, pons and medulla, midbrain, cortex and spinal cord of WKY and SHR rats did not differ. The Bmax value of 3H-naltrexone binding to membranes of hypothalamus of SHR rats was 518% higher than WKY rats but the Kd values in the two strains did not differ. It is concluded that SHR rats have higher density of opiate receptors labeled with 3H-naltrexone in the hypothalamus only, in comparison with WKY rats, and that such a difference in the density of opiate receptors may be related to the elevated blood pressure in SHR rats. 相似文献
172.
The effect of chronic administration of morphine and its withdrawal on the binding of 3H-[3-MeHis2]thyrotropin releasing hormone (3H-MeTRH) to membranes of the spinal cord of the rat was determined. Male Sprague-Dawley rats were implanted with either 6 placebo or 6 morphine pellets (each containing 75-mg morphine base) during a 7-day period. Two sets of animals were used. In one, the pellets were left intact at the time of sacrificing (tolerant-dependent) and in the other, the pellets were removed 16 hours prior to sacrificing (abstinent rats). In placebo-pellet-implanted rats, 3H-MeTRH bound to the spinal cord membranes at a single high affinity binding site with a Bmax of 21.3 +/- 1.6 fmol/mg protein, and an apparent dissociation constant Kd of 4.7 +/- 0.8 nM. In morphine tolerant-dependent or abstinent rats, the binding constants of 3H-MeTRH to spinal cord membranes were unaffected. Previous studies from this laboratory indicate that TRH can inhibit morphine tolerance-dependence and abstinence processes without modifying brain TRH receptors. Together with the present results, it appears that the inhibitory effect of TRH on morphine tolerance-dependence and abstinence is probably not mediated via central TRH receptors but may be due to its interaction with other neurotransmitter systems. 相似文献
173.
Amel Belaroussi Fatima Labed Aicha Khenifi Rachid Ait Akbour Zohra Bouberka Mostéfa Kameche Zoubir Derriche 《农业工程》2018,38(2):148-156
Adsorption processes of 4GL on two different bentonite-based sorbents were compared: i) Sodium-bentonite in the presence of a cationic surfactant CTAMB; ii) organobentonite alone. This latter was prepared by exchanging the inorganic cation of bentonite with a quaternary ammonium cation at 100% of the clay's CEC. Batch adsorption studies were conducted to evaluate the effect of various parameters such as the quaternary ammonium cation (CTAMB) loading, contact time and initial 4GL concentration.From the kinetic study, it is interesting to note that Organobentonite exhibits faster kinetics compared to Na-bentonite/CTAMB system. The comparison between isotherm plots makes clear that the presence of CTAMB in solution changes the 4GL isotherm. Compared to organobentonite, the adsorption capacity is higher when CTAMB was present in solution. In this case, the results of 4GL adsorption by bentonite obey to Langmuir model. While for organobentonite, all models seem to be applicable. The difference between the two methods is confirmed by XRD analysis.The performance shown by Organobentonite and Na-bentonite/CTAMB system was suitable compared to other adsorbents, reflecting a promising future utilization in wastewater treatment. 相似文献
174.
Nanik Rahmani Prihardi Kahar Puspita Lisdiyanti Euis Hermiati Jaemin Lee Yopi 《Bioscience, biotechnology, and biochemistry》2018,82(5):904-915
The addition of enzymes that are capable of degrading hemicellulose has a potential to reduce the need for commercial enzymes during biomass hydrolysis in the production of fermentable sugars. In this study, a high xylanase producing actinomycete strain (Kitasatospora sp. ID06-480) and the first ethyl ferulate producing actinomycete strain (Nonomuraea sp. ID06-094) were selected from 797 rare actinomycetes, respectively, which were isolated in Indonesia. The addition (30%, v/v) of a crude enzyme supernatant from the selected strains in sugarcane bagasse hydrolysis with low-level loading (1 FPU/g-biomass) of Cellic® CTec2 enhanced both the released amount of glucose and reducing sugars. When the reaction with Ctec2 was combined with crude enzymes containing either xylanase or feruloyl esterase, high conversion yield of glucose from cellulose at 60.5% could be achieved after 72 h-saccharification. 相似文献
175.
176.
The objective of this study was to assess the relationship between river water quality and the distribution of benthic macroinvertebrate communities in the Haraz River in Iran. Using a surber net sampler, benthic macroinvertebrate communities along the stream was sampled in wet and dry seasons of 2015 at nine stations with three replications. The physicochemical water quality parameters were measured in the field by water checker. Hilsenhoff biotic Indices, Shannon Wiener Diversity Indices, Average Score per Taxon (ASPT) Index and Pielou Evenness Index were applied to carry out a biological assessment of water quality. A total of 3781 (spring 769, summer 1092, autumn 1095 and winter 825) benthic macroinvertebrate specimens belonging to 4 orders, 11 classes and 16 families were identified. The lowest number of taxa was recorded in spring while the highest was recorded in autumn. Station 9 had the lowest number of taxa while the highest number of taxa was recorded at station 3. The average values (±SD) of the water quality parameters were temperature 14.75?±?4.38 °C, pH 7.93?±?0.62, water flow 14.11?±?9.04 m3 s?1, electric conductivity 532.75?±?161.35 μmohs cm?1, total dissolved solids 296.61?±?76.21 mg L?1, salinity 0.28?±?0.07 mg L?1, turbidity 580.77?±?149.92 NTU and dissolved oxygen 8.08?±?0.75 mg L?1. The assessment of stations 1 to 6 indicated that water quality conditions were suitable. In addition, substantial level of organic pollution was observed in stations 7 and 8. In station 9 water quality was fairly poor, requiring a more favourable management based on the capacity of the self-purification of the Haraz River. 相似文献
177.
T M Rahmani 《Acta anatomica》1984,119(4):203-209
The ability of stage-4-9 chick presumptive lens ectoderm to undergo nervous tissue or lens differentiation was studied in vitro. The tissue was cultured alone or co-cultured with alcohol-killed primitive node or optic cup as inducer. Immunofluorescence was studied on paraffin-wax preparations, which were then studied histologically. An attempt was made to correlate immunological and histological differentiation. The presumptive lens ectoderm differentiated both nervous tissue and lens structures in all stages, regardless of the presence or absence of an inducer. The outcome, however, was improved when an inducer was included. The inducers were not qualitatively specific. The stage-4 ectoderm proved to be more apt than older stages to differentiate nervous tissue and form neural tube-like structures. In the former stage, lens differentiation occurred with less readiness. Older stages differentiated lens structures readily and also showed immunological signs of nervous tissue differentiation. No indication of histological differentiation, however, was apparent and no neural tube-like structures formed. 相似文献
178.
Vahidinia Aliasghar Samiee Fateme Faradmal Javad Rahmani Alireza Taravati Javad Masoumeh Leili Mostafa 《Biological trace element research》2019,187(1):32-40
Biological Trace Element Research - Breast milk is considered the best source of nutrition for all infants. However, exposure of newborns to toxic metals is of special interest due to their... 相似文献
179.
Smith CA Lau KM Rahmani Z Dho SE Brothers G She YM Berry DM Bonneil E Thibault P Schweisguth F Le Borgne R McGlade CJ 《The EMBO journal》2007,26(2):468-480
In Drosophila, the partition defective (Par) complex containing Par3, Par6 and atypical protein kinase C (aPKC) directs the polarized distribution and unequal segregation of the cell fate determinant Numb during asymmetric cell divisions. Unequal segregation of mammalian Numb has also been observed, but the factors involved are unknown. Here, we identify in vivo phosphorylation sites of mammalian Numb and show that both mammalian and Drosophila Numb interact with, and are substrates for aPKC in vitro. A form of mammalian Numb lacking two protein kinase C (PKC) phosphorylation sites (Numb2A) accumulates at the cell membrane and is refractory to PKC activation. In epithelial cells, mammalian Numb localizes to the basolateral membrane and is excluded from the apical domain, which accumulates aPKC. In contrast, Numb2A is distributed uniformly around the cell cortex. Mutational analysis of conserved aPKC phosphorylation sites in Drosophila Numb suggests that phosphorylation contributes to asymmetric localization of Numb, opposite to aPKC in dividing sensory organ precursor cells. These results suggest a model in which phosphorylation of Numb by aPKC regulates its polarized distribution in epithelial cells as well as during asymmetric cell divisions. 相似文献
180.
Wafa Ben-Cherif Ichrak Dridi Zohra Haouas Abdelhedi Miled Karim Aouam Mossadok Ben-Attia 《Biological Rhythm Research》2015,46(6):847-861
This study aims to investigate whether hepatic and renal valproic acid (VPA) toxicities varied according to the dosing time in the 24-h scale in mice. VPA was administered by i.p. route to different groups of animals at four different circadian stages (1, 7, 13, and 19 h after light onset (HALO)). Biochemical study and histopathological examinations on liver and kidney sections were performed. The results showed that the hepatic and renal toxicity induced by VPA was time related. Animals treated at 19 HALO showed vacuolar degenerative changes, congestions, and inflammatory areas on liver parenchyma. Lesions within proximal tubules were observed in the kidney in groups treated at 19 HALO. The largest increases in alanine aminotransferase, alkaline phosphatase and plasma creatinine activities were also observed at 19 HALO. The obtained data indicate that the optimal hepatic and renal tolerance is observed when VPA was injected in the middle of the light-rest span of mice. 相似文献