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711.
Seden Demirci Süleyman Kutluhan Mustafa Nazıroğlu Abdülhadi Cihangir Uğuz Vedat Ali Yürekli Kadir Demirci 《Neurochemical research》2013,38(1):90-97
It has been widely suggested that selenium (Se) deficiency play an important role in the pathophysiology of epilepsy. It has been reported that Se provides protection against the neuronal damage in patients and animals with epilepsy by restoring the antioxidant defense mechanism. The neuroprotective effects of topiramate (TPM) have been reported in several studies but the putative mechanism of action remains elusive. We investigated effects of Se and TPM in neuronal PC12 cell by evaluating Ca2+ mobilization, lipid peroxidation and antioxidant levels. PC12 cells were divided into eight groups namely control, TPM, Se, H2O2, TPM + H2O2, Se + H2O2, Se + TPM and Se + TPM + H2O2. The toxic doses and times of H2O2, TPM and Se were determined by cell viability assay which is used to evaluate cell viability. Cells were incubated with 0.01 mM TPM for 5 h and 500 nM Se for 10 h. Then, the cells were exposed to 0.1 mM H2O2 for 10 h before analysis. The cells in all groups except control, TPM and Se were exposed to H2O2 for 15 min before analysis. Cytosolic Ca2+ release and lipid peroxidation levels were higher in H2O2 group than in control, Se and TPM combination groups although their levels were decreased by incubation of Se and TPM combination. However, there is no difference on Ca2+ release in TPM group. Glutathione peroxidase activity, reduced glutathione and vitamin C levels in the cells were lower in H2O2 group than in control, Se and TPM groups although their values were higher in the cells incubated with Se and TPM groups than in H2O2 groups. In conclusion, these results indicate that Se induced protective effects on oxidative stress in PC12 cells by modulating cytosolic Ca2+ influx and antioxidant levels. TPM modulated also lipid peroxidation and glutathione and vitamin C concentrations in the cell system. 相似文献
712.
Abd El-Fatah Bahaa E. S. Sayed Mohammed A. El-Sanusy Sahar A. 《Molecular biology reports》2020,47(12):9289-9300
Molecular Biology Reports - Anther culture is the most effective tool for doubled haploid production of wheat. This investigation was conducted to estimate genetic parameters of anther culture... 相似文献
713.
Revandy Iskandar Damanik Mohd Razi Ismail Zulkifli Shamsuddin Sariam Othman Abd Mohd Zain Mahmood Maziah 《Plant Growth Regulation》2012,67(1):83-92
The effect of oxygen deprivation (anoxia) on the antioxidant system in suspension culture of anoxia-intolerant Malaysian rice mutants cells was examined. Abiotic stresses have been reported to adversely affect cell division, damage cellular and organelle membranes. The signaling defense mechanisms, such as molecular and biochemical aspects responding to stress have been proven to be very complex, and still largely untapped. The objective of this study was to determine the potential involvement of activated oxygen species, such as superoxide dismutase, catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase which occur in cells of rice plants exposed to anoxia stress in two Malaysian rice mutants, MR219-4 and MR219-9, and rice cultivar FR13A which is known to be tolerant to anoxia stress during 5–30 days of exposure. The antioxidative enzymes were decreased for MR219-4 and MR219-9 mutants for CAT and APX activities, and increased in FR13A cultivar starting at 20 days in suspension culture compared to that of control. CAT and APX activities were maintained higher in anoxia condition for all mutants and cultivar. These findings suggested that anoxia stress in suspension cultures induced the level of H2O2 to toxic levels. 相似文献
714.
715.
Sousou Ibrahim Ali Naglaa Fathy Alhusseini Reham Abd El-Satar Idris Rehab Abdallah Hasan 《Free radical research》2016,50(9):966-986
Obesity enhances the frequency and severity of acute kidney injury (AKI). Telmisartan pre-treatment was used experimentally in the amelioration of ischemia/reperfusion (IR)-induced AKI. However, there is a lack of evidence regarding its beneficial effects on AKI in obese animals. The present study, therefore, aimed to explore the protective effects of garlic and/or telmisartan against renal damage induced by unilateral IR in obese rats. Meloxicam was used as a standard anti-inflammatory agent. Prophylactic oral administration of meloxicam (3?mg kg?1), garlic (500?mg kg?1) and/or telmisartan (5 and 10?mg kg?1) for 4 wk protected against renal function deterioration induced by IR in obese rats. Both doses of telmisartan significantly reduced serum total cholesterol and triacyglycerol levels as well as peri-renal adipocytes size and renal fibrosis. Renal nuclear factor-kappa B immunoreactivity, tumor necrosis factor-alpha content as well as interleukin-10, adiponectin receptor 1 and macrophages (M1, M2) polarization markers (CD11c, CD206) mRNA expressions were down-regulated in ischemic kidney tissues and white adipose tissues around them by all treatments. Moreover, garlic, telmisartan and their combinations significantly suppressed oxidative stress in renal ischemic tissues. Histological picture was also improved by these treatments. Interestingly, the combinations provided a greater protection than their monotherapy in a dose-dependent manner. We suppose that this combination may be a promising prophylactic regimen for managing AKI in case of obesity. Thus, future experimental and clinical large-scale studies are necessary. 相似文献
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718.
El-Rahman Mansy Abd El-Bestawy Ebtesam 《World journal of microbiology & biotechnology》2002,18(2):125-131
The Biodegradation capabilities of six selected cyanobacterial species for fluometuron, a phenylurea herbicide, as well as its inhibitory effect on chlorophyll a content were investigated. The selected species (three strains of Microcystis aeruginosa, Anabaena cylindrica, A. flos-aquae and A. spiroides) were subjected to three elevated concentrations of fluometuron (0.14, 0.7 and 1.4 mg/ml) for different exposure times (1–5 days). Results revealed that biodegradation of fluometuron is species-dependent and positively correlated with the exposure time, reaching maximum efficiency after 5 days at all the investigated concentrations. All the species tested showed generally great ability to degrade the compound even at the highest concentration with specific variations among them. Biodegradation efficiencies of fluometuron by the selected species were in the following ranges; 39.2–99.9; 87.5–100; and 93.2–100 at 0.14; 0.7 and 1.4 mg fluometuron/ml respectively. It was noticed that the gradual increase in the pesticide concentration enhances its biodegradability by the selected algal species. Variations according to species as well as exposure time were discussed. The highest fluometuron concentration (1.4 mg/l) showed the highest inhibition of chlorophyll a content in the tested species and toxicity was also species- and time-dependent. 相似文献
719.
Over the past decade, L-homophenylalanine is extensively used in the pharmaceutical industry as a precursor for production of angiotensin-converting enzyme (ACE) inhibitor, which possesses significant clinical application in the management of hypertension and congestive heart failure (CHF). A number of chemical methods have been reported thus far for the synthesis of L-homophenylalanine. However, chemical methods generally suffer from process complexity, high cost, and environmental pollution. On the other hand, enantiomerically pure L-homophenylalanine can be obtained elegantly and efficiently by employing biocatalytic methods, where it appears to be the most attractive process in terms of potential industrial applications, green chemistry and sustainability. Herein we review the biocatalytic synthesis of vital L-homophenylalanine as potentially useful intermediate in the production of pharmaceutical drugs in environmentally friendly conditions, using membrane bioreactor for sustainable biotransformation process. One envisages the future prospects of developing an integrated membrane bioreactor system with improved performance for L-homophenylalanine production. 相似文献
720.
A. Abu-Hashem M. A. Abd Al-Halim M. A. Hassouba M. M. Masoud 《Plasma Physics Reports》2010,36(3):271-278
A dc cylindrical coaxial glow discharge with an inner grid anode has been studied. The region between the two electrodes is
seen dark, while a brightly glowing region forms inside the grid anode up to the center. The current-voltage characteristic
of a dc cylindrical glow discharge in nitrogen is similar to that of a normal glow discharge, while the normal glow discharge
voltage decreases with increasing pressure. The minimum plasma potentials are observed in the hollow cathode region due to
the accumulation of electrons at the back of the grid anode. At the center, some of the passed electrons are converged, so
their potential is decreased. These electrons have a sufficient time to be redistributed to form one group with a Maxwellian
electron energy distribution function. The electron temperature measured by electric probes varies from 1.6 to 3.6 eV, while
the plasma density varies from 3.9 × 1016 to 7 × 1013 m−3, depending on the discharge current and probe position. The plasma density increases as the electrons move radially from
the grid toward the central region, while their temperature decreases. 相似文献