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Microalgae cultivation for biofuels production and other applications has gained considerable interest recently. Despite their simple structures, microalgae can accumulate significant amounts of neutral lipids per dry cell weight compared to other energy crops. Neochloris oleoabundans is a promising microalga known for its high lipid content and biomass growth rate compared to other species cultivated for biofuels synthesis; therefore, it is considered as a suitable candidate for biodiesel synthesis. This review paper covers several key aspects associated with the cultivation and applications of the microalga N. oleoabundans. Biomass composition, factors affecting the growth, and biomass and lipid productivities of this species were addressed. In addition, different growth conditions as well as alternative readily available nutrient media to support the growth of N. oleoabundans were presented in this review.  相似文献   
33.
1,3-Diaminopropane has been detected, together with spermidine, in cucumber seeds. Quantitative estimation of the two metabolites in cucumber seeds and germinating seedlings (up to 21 days old) showed that the concentrations of both metabolites increased, then decreased with age. A metabolic sequence linking spermidine, 1,3-diaminopropane and the non-protein amino acid β-pyrazol-1-yl alanine was suggested.  相似文献   
34.

Objectives

Alpha-1 antitrypsin (A1AT) deficiency is associated with emphysema and liver disease. Only plasma-derived A1AT protein is available for augmentation therapy. Recombinant A1AT (recA1AT) protein expressed in various types of available hosts are either non-glycosylated or aberrantly glycosylated resulting into reduced stability and biological activity. To overcome these limitations, we have used the human liver HepG2 cell line to produce recA1AT protein.

Results

HepG2 cells were transfected by A1AT cDNA and cell populations were generated that stably overexpressed A1AT protein. Real-time RT-PCR and rocket immunoelectrophoresis of cell culture supernatants indicated that the transfection resulted more than two-fold increase in A1AT production compared to that of control parental cells. Immunoblot analysis showed that both plasma and HepG2-produced A1AT proteins have identical molecular weight in either glycosylated or deglycosylated form. Partial digestion with PNGase F indicated that the three N-glycosylation sites of recA1AT, like the native A1AT protein in plasma, are occupied. Recombinant A1AT also like the native A1AT was thermostable and could efficiently inhibit trypsin proteolytic activity against BSA and BAPNA chromogenic substrate. The recombinant HepG2 cells cultured in media containing B27 serum free supplement released recA1AT at the same level as in the serum containing media.

Conclusions

RecA1AT production in HepG2 cells grown under serum free condition at a large scale could provide a reliable source of the native protein suitable for therapeutic use in human.
  相似文献   
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Molecular Biology Reports - Cellulases like endoglucanase II (EGII) from Trichoderma reesei are the industrial enzymes responsible for breakdown of cellulosic materials. Due to its importance for...  相似文献   
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38.

Objectives

Clinical characteristics and trends in the outcome of acute coronary syndrome (ACS) in patients with prior coronary artery bypass graft surgery (CABG) are unclear. The aim of this study was to evaluate clinical characteristics, in-hospital treatment, and outcomes in patients presented with ACS with or without a history of prior CABG over 2 decades.

Methods

Data were derived from hospital-based study for collected data from 1991 through 2010 of patients hospitalized with ACS in Doha, Qatar. Data were analyzed according to their history of prior CABG. Baseline clinical characteristics, in-hospital treatment, and outcome were compared.

Results

A total 16,750 consecutive patients with ACS were studied, of which 693 (4.1%) had prior CABG. Patients with prior CABG were older (mean 60.5±11 vs. 53±12 years; P = 0.001), more likely to be females and have more cardiovascular risk factors than the non-CABG group. Prior CABG patients had larger infarct size, were less likely to receive reperfusion therapy, early invasive therapy and more likely to receive evidence-based therapies when compared to non-CABG patients. In-hospital mortality and stroke rates were comparable between the 2 groups. Over 2 decades, there was reduction in the in-hospital mortality rates and stroke rates in both groups (CABG, death; 13.2% to 4%, stroke; 1.9% to 0.0%, non-CABG, death; 10% to 3.2%, stroke 1.0% to 0.1%; all, p = 0.001).

Conclusion

Significant reduction in-hospital morbidity and mortality among ACS patients with prior CABG over a 20-year period.  相似文献   
39.
Purple acid phosphatases (PAPs) are binuclear metallohydrolases that have been isolated from various mammals, plants, fungi and bacteria. In mammals PAP activity is associated with bone resorption and can lead to bone metabolic disorders such as osteoporosis; thus human PAP is an attractive target to develop anti-osteoporotic drugs. Based on a previous lead compound and rational drug design, acyl derivatives of α-aminonaphthylmethylphosphonic acid were synthesised and tested as PAP inhibitors. Kinetic analysis showed that they are good PAP inhibitors whose potencies improve with increasing acyl chain length. Maximum potency is reached when the number of carbons in the acyl chain is between 12 and 14. The most potent inhibitor of red kidney bean PAP is the dodecyl-derivative with Kic = 5 μM, while the most potent pig PAP inhibitor is the tetradecyl-derivative with Kic = 8 μM, the most potent inhibitor of a mammalian PAP yet reported.  相似文献   
40.
Environmental variables such as temperature are important factors that affect the efficiency of biological control agents. This study examined the effect of temperature on the sex ratio, longevity, oviposition periods, fecundity and life table parameters of the predatory thrips Scolothrips longicornis Priesner (Thysanoptera: Thripidae) fed on twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), at six constant temperatures: 15, 20, 26, 30, 35, and 37 degrees C. Approximately 75% of the progeny were female, except at 37 degrees C, at which temperature the proportion of males increased. Adult longevity as well as the preoviposition, oviposition, and postoviposition periods decreased significantly with temperature. Thus, adults lived for approximately 5 wk at 15 degrees C and < 1 wk at 37 degrees C with preoviposition, oviposition, and postoviposition periods ranging from 6.4 to 0.4, 24.4-3.1, and 7-0.8 d between the two temperature extremes, respectively. The maximum (56.48 eggs) and minimum (11.69 eggs) value of total fecundity was recorded at 26 and 37 degrees C, respectively. The intrinsic rate of natural increase (r(m)) of S. longicornis increased linearly with increasing temperature from 0.056 d(-1) at 15 degrees C to 0.310 d(-1) at 35 degrees C. The lower temperature threshold for the population increase of S. longicornis was estimated to be around 5 degrees C. The data suggest that the upper temperature threshold for the predatory thrips is approximately 37 degrees C. The results showed that populations of S. longicornis are able to develop at a broad range of temperatures and that this predator is well adapted to the high temperatures that occur in the Mediterranean region.  相似文献   
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