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121.
Production of lipid from oleaginous yeast using starch as a carbon source is not a common practice; therefore, the purpose of this investigation was to explore the capability of starch assimilating microbes to produce oil, which was determined in terms of biomass weight, productivity, and lipid yield. Saccharomyces pastorianus, Rhodotorula mucilaginosa, Rhodotorula glutinis, and fungal isolate Ganoderma wiiroense were screened for the key parameters. The optimization was also performed by one-factor-at-a-time approach. Considering the specific yield of lipid and cell dry weight yield, R. glutinis and R. mucilaginosa showed superiority over other strains. G. wiiroense, a new isolate, would also be a promising strain for starch waste utilization in terms of extracellular and intracellular specific yield of lipids. Extracellular specific yield of lipid was highest in R. glutinis culture (0.025?g?g?1 of biomass) followed by R. mucilaginosa (0.022?g?g?1 of biomass) and G. wiiroense (0.020?g?g?1 of biomass). Intracellular lipid was again highest in R. glutinis (0.048?g?g?1 of biomass). The most prominent fatty acid methyl esters among the lipid as detected by GC-MS were saturated lipids mainly octadecanoic acid, tetradecanoate, and hexadecanoate. Extracellular lipid produced on starch substrate waste would be a cost-effective alternative for energy-intensive extraction process in biodiesel industry.  相似文献   
122.
This study was executed to determine phytochemical content i.e. total carotenoids, phenolics and flavonoids, and antioxidant ability expressed in the form of FRAP, CUPRAC and ABTS activity among different coloured tropical carrots (orange, red, yellow, rainbow and black carrot) developed at ICAR-IIVR, Varanasi, Uttar Pradesh, India. Overall, within different colour group, the extent of variation for various phytochemical content and antioxidant potentiality is narrow i.e. ranged from 1.04- to 3.21-fold; but at the same time, the genotypic variability across genotypes is too wide which varied 20.90- to 57.92-fold for phytochemical and antioxidants is an indication of broad genetic base of carrot germplasm. Among all the carrots, black carrot had an exceptionally high content of total phenolics and flavonoids, and thereby led to the highest antioxidant ability in the terms of FRAP, CUPRAC and ABTS activity expressing about 76–83% relative potentiality followed by rainbow carrot, and least in orange, red and yellow carrot (black carrot?>?rainbow carrot?>?red carrot?≈?orange carrot?≈?yellow carrot). The content of phenolics and flavonoids were highly correlated with antioxidant activity (0.955** to 0.992**). However, the most cultivated and consumed carrots, orange and red one, possessed higher amount of carotenoids. The content of carotenoids negatively correlated with total phenolics, flavonoids and antioxidants activity (??0.612** to ??0.627**). Broad genetic base and selection based on total phenolics content could be pivotal in the future breeding to harness the genetic wealth of carrot efficiently.  相似文献   
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Autoimmune vasculitis is an endothelial inflammatory disease that results from the deposition of immune-complexes (ICs) in blood vessels. The interaction between Fcgamma receptors (FcγRs) expressed on inflammatory cells with ICs is known to cause blood vessel damage. Hence, blocking the interaction of ICs and inflammatory cells is essential to prevent the IC-mediated blood vessel damage. Thus we tested if uncoupling the interaction of FcγRs and ICs prevents endothelium damage. Herein, we demonstrate that dimeric FcγR-Igs prevented nitric oxide (NO) mediated apoptosis of human umbilical vein endothelial cells (HUVECs) in an in vitro vasculitis model. Dimeric FcγR-Igs significantly inhibited the IC-induced upregulation of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) release by murine monocytic cell line. However, FcγR-Igs did not affect the exogenously added NO-induced upregulation of pro-apoptotic genes such as Bax (15 fold), Bak (35 fold), cytochrome-C (11 fold) and caspase-3 (30 fold) in HUVECs. In conclusion, these data suggest that IC-induced NO could be one of the major inflammatory mediator promoting blood vessel inflammation and endothelial cell death during IC-mediated vasculitis which can be effectively blocked by dimeric decoy FcγRs.  相似文献   
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The present study aimed at investigating the effect of shift work on circadian time structure of several variables, such as skin temperature (ST), heart rate (HR), peak expiratory flow rate (PEFR), subjective drowsiness (SDr), subjective fatigue (SF) and subjective attention (SA) in shift workers of a sub-urban cement factory. Six shift workers volunteered for this study. In each subject, above mentioned variables were monitored at least 4-6 times per day for over a period of one week. The study was conducted in two different spells. In the first spell (1994), circadian time structure of six shift workers was studied about 14 months after slowing down of overall functioning of the cement factory. In the second spell (1996), the circadian time structure of the same subjects was reexamined following about 30 months of slough in the cement factory. The results indicate that the rhythm desynchronization of ST, HR and PEFR was witnessed among shift workers in 1994. However, when all six shift workers were monitored again in 1996, the desynchronized rhythm became synchronized in most of the shift workers. Further, in the present study it was noticed that subjective variables, such as SF and SA are less prone to desynchronization as compared to other objective variables. The relative stability of rhythms in fatigue and attention could also be ascribed to the period of sleep-wake rhythm that remained either 24 h or very close to 24 h irrespective of the year of study. In conclusion, the findings of this study document rigorously that externally desynchronized circadian rhythms in shift workers could become normal following their transfer from shift work to diurnal work.  相似文献   
125.
Wounds are known to serve as portals of entry for group A Streptococcus (GAS). Subsequent tissue colonization is mediated by interactions between GAS surface proteins and host extracellular matrix components. We recently reported that the streptococcal collagen‐like protein‐1, Scl1, selectively binds the cellular form of fibronectin (cFn) and also contributes to GAS biofilm formation on abiotic surfaces. One structural feature of cFn, which is predominantly expressed in response to tissue injury, is the presence of a spliced variant containing extra domain A (EDA/EIIIA). We now report that GAS biofilm formation is mediated by the Scl1 interaction with EDA‐containing cFn. Recombinant Scl1 proteins that bound cFn also bound recombinant EDA within the C‐C’ loop region recognized by the α9β1 integrin. The extracellular 2‐D matrix derived from human dermal fibroblasts supports GAS adherence and biofilm formation. Altogether, this work identifies and characterizes a novel molecular mechanism by which GAS utilizes Scl1 to specifically target an extracellular matrix component that is predominantly expressed at the site of injury in order to secure host tissue colonization.  相似文献   
126.
The effects of peripheral layer viscosity on physiological characteristics of blood flow through the artery with mild stenosis have been studied. It has been shown that the resistance to flow and the wall shear decrease as the peripheral layer viscosity decreases.  相似文献   
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Phenylalanine ammonia-lyase and cinnamate 4-hydroxylase are important enzymes in allocating significant amounts of carbon from phenylalanine into the biosynthesis of several important secondary metabolites. Tea is an important crop of commerce known for its beverage and medicinally important flavonoid compounds, mainly catechins. As metabolic flux for the operation of the flavonoid pathway is maintained through the activities of PAL and C4H, thus, catechins biosynthesis in tea is critically dependent on the products of these enzymes. We examined the expression of PAL and C4H. Sequence encoding CsPAL was isolated from tea by polymerase chain reaction using sequence information available at the NCBI GenBank. Sequence encoding C4H was isolated from tea by using differential display of mRNA and rapid amplification of cDNA ends technology. CsC4H (AY641731) comprised of 1,352 bp full-length cDNA with open reading frame of 1,173 bp encoding 390 amino acids. Catechin contents decreased in response to drought stress (DS), abscisic acid (ABA), and gibberellic acid (GA3) treatments but increased in response to wounding. The expression of CsPAL and CsC4H showed the same behavior under the above treatments and was also in accordance with the catechin contents. A positive correlation between catechin contents and gene expression suggested a critical role of the enzymes in catechins biosynthesis and a crosstalk between phenylpropanoid and flavonoid pathways.  相似文献   
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