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1.
E. V. Esin 《Journal of Ichthyology》2009,49(9):777-785
Seinings of the lowland bed of a typical small river of Western Kamchatka demonstrated that of several methods for the census
of juveniles of salmonids (Salmonidae) the most accurate result in comparison with complete removal is obtained by three-fold
seining with calculation of abundance by the Zippin method. In comparison with a seine, a drive-in trap and electrofishing
possess a lower average catching efficiency and a higher selectivity. The average density of fish estimated by the results
of seining at the investigated stretch was 0.55–0.57 specimens/m2. 相似文献
2.
A mathematical model of a rabbit sinoatrial node cell 总被引:3,自引:0,他引:3
3.
Mesut Aydin Yaren Dirik Canan Demir Harun Egemen Tolunay Halit Demir 《Journal of Medical Biochemistry》2021,40(4):351
BackgroundThe aim of this study was to determine the levels of lipid peroxidation (MDA) and antioxidants such as reduced glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) in the blood serum of patients with cirrhosis and liver transplantation.MethodsIn this study, serum malondialdehyde acid (MDA) levels, superoxide dismutase (SOD), reduced glutathione (GSH), and catalase (CAT) activities were measured spectrophotometrically and compared to the results of the healthy control group.ResultsSOD, CAT and GSH activities were significantly decreased in the patient groups compared to the healthy control group (p<0.05). MDA levels were significantly higher in the patient group compared to the healthy control group (p <0.05).ConclusionsIn conclusion, this study demonstrated that oxidative stress may play an important role in the development of liver cirrhosis and in liver transplantation. This study is the first one to show how MDA, SOD, CAT and GSH levels change in liver cirrhosis and liver transplantation, while further studies are essential to investigate antioxidant enzymes and oxidative stress status in patients with cirrhosis and liver transplantation. 相似文献
4.
Voltage-gated potassium channels control the membrane potential of excitable cells. To understand their function, knowledge of their structure is essential. However, these channels are scarce in natural sources, and overexpression is necessary to generate material for structural studies. We have compared functional expression of the Drosophila Shaker H4 potassium channel in stable insect cell lines and in baculovirus-infected insect cells, using three different baculovirus promoters. Stable insect cell lines expressed correctly assembled channel, which was glycosylated and found predominantly at, or close to, the cell surface. In comparison, the majority of baculovirus-overexpressed Shaker was intracellular and incorrectly assembled. The proportion of functional Shaker increased, however, if the weaker basic protein promoter was used rather than the stronger p10 or polyhedrin promoters. In addition, co-expression of the molecular chaperone, calnexin, increased the quantity of correctly assembled channel protein, suggesting that calnexin can be used to increase the efficiency of channel expression in insect cells. 相似文献
5.
Cihan Gokce Huseyin Yilmaz Zeynep Erbas Zihni Demirbag Ismail Demir 《Journal of nematology》2013,45(4):253-259
During a survey of entomopathogenic nematodes (EPNs) in the eastern Black Sea region of Turkey in 2009–2012, a steinernematid species was recorded and isolated using the Galleria-baiting method. The isolate was identified as Steinernema kraussei based on its morphological and molecular properties. The analysis of the ITS rDNA sequence placed the Turkish population of S. kraussei in the “feltiae-kraussei” group in the clade that contains different isolates of the species. This is the first record of S. kraussei from Turkey. The efficacy of S. kraussei was tested on Agrotis segetum (Lepidoptera: Noctuidea) larvae at different densities (100, 300, and 500 infective juveniles (IJs) g−1 dry sand ) in laboratory conditions at 25 °C. The highest mortality (98%) was obtained with 500 IJs g−1 dry sand within 7 d after inoculation. Our results indicate that the new isolate is a highly promising biological control agent against A. segetum, one of the most serious soil pests of agricultural area and fruits worldwide. 相似文献
6.
Sevdegul Karadas Refah Sayın Mehmet Aslan Hayriye Gonullu Celal Katı Recep Dursun Latif Duran Edip Gonullu Halit Demir 《The Journal of membrane biology》2014,247(2):175-180
Trace elements are essential components of biological structures, but alternatively, they can be toxic at concentrations beyond those necessary for their biological functions. Changes in the concentration of essential trace elements and heavy metals may affect acute hemorrhagic stroke. The aim of this study was to measure serum levels of essential trace elements [iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and magnesium (Mg)] and heavy metals [cobalt (Co), cadmium (Cd), and lead (Pb)] in patients with acute hemorrhagic stroke. Twenty-six patients with acute hemorrhagic stroke and 29 healthy controls were enrolled. Atomic absorption spectrophotometry (UNICAM-929) was used to measure serum Fe, Cu, Pb, Cd, Zn, Co, Mn and Mg concentrations. Serum Cd, Pb and Fe levels were significantly higher in patients with acute hemorrhagic stroke than controls (p < 0.001), while serum Cu, Zn, Mg and Mn levels were significantly lower (all p < 0.001). However, there was no significant difference between the groups with respect to serum Co levels (p > 0.05). We first demonstrate increased Cd, Pb, and Fe levels; and decreased Cu, Zn, Mg, and Mn levels in patients with acute hemorrhagic stroke. These findings may have diagnostic and prognostic value for acute hemorrhagic stroke. Further studies are required to elucidate the roles of trace elements and heavy metals in patients with acute hemorrhagic stroke. 相似文献
7.
The angular dependencies of inelastic intensities of Rayleigh scattering of Moessbauer radiation were measured for myoglobin and lysozyme (in the hydration range h = 0.05-0.7). The data were fitted within the framework of model, when two types of intraglobular motions were taken into account: individual motions of small side-chain groups and cooperative motions of segments. The best agreement with the experiment at h > 0.05 was obtained when individual motions of small groups together with the cooperative motions of alpha-helices and beta-sheets for lysozyme, and alpha-helices for myoglobin were considered. At further hydration (h = 0.45), mean-square displacements (x2) of both types of motions strongly increase with the increase in hydration degree, while the motions with a large correlation radius (not less than macromolecule radius) remain nearly the same as for h = 0.05. The results of the study of the radial distribution function deduced by Fourier-transform from the diffuse x-ray measurements together with RSMR data allow one to conclude that the water during protein hydration competes with the intramolecular hydrogen bonds, loosens the protein and increases the internal dynamics. Concurrently, water arranges the ordering of macromolecule, which takes the native structure at h = 0.4-0.7. The analysis of auto and cross-correlation functions of bending fluctuations of alpha-helices in the large domain of lysozyme performed by molecular dynamics allows one to come to the final conclusion that it is the difference in the structural organization of myoglobin and lysozyme and not the presence of SS-bonds in lysozyme macromolecule that is responsible for different structural fluctuations in these proteins. 相似文献
8.
9.
Gecit İ Kavak S Meral I Güneş M Pirinççi N Sayir F Demir H Ceylan K 《Cell biochemistry and function》2012,30(4):303-308
This study was designed to investigate whether the short-term extracorporeal shockwave lithotripsy (ESWL) exposure to kidney produces an oxidative stress and a change in some trace element levels in liver and diaphragm muscles of rats. Twelve male Wistar albino rats were divided randomly into two groups, each consisting of six rats. The animals in the first group did not receive any treatment and served as control group. The right-side kidneys of animals in group 2 were treated with two-thousand 18 kV shock waves while anesthetized with 50 mg kg(-1) ketamine. The localization of the right kidney was achieved after contrast medium injection through a tail vein under fluoroscopy control. The animals were killed 72 h after the ESWL treatment, and liver and diaphragm muscles were harvested for the determination of tissue oxidative stress and trace element levels. Although the malondialdehyde level increased, superoxide dismutase and glutathione peroxidase enzyme activities decreased in the livers and diaphragm muscles of ESWL-treated rats. Although glutathione level increased in liver, it decreased in diaphragm muscles of ESWL-treated animals. Fe, Mg and Mn levels decreased, and Cu and Pb levels increased in the livers of ESWL-treated animals. Fe and Cu levels increased, and Mg, Pb, Mn and Zn levels decreased in the diaphragm muscles of ESWL-treated animals. It also causes a decrease or increase in many mineral levels in liver and diaphragm muscles, which is an undesirable condition for the normal physiological function of tissues. 相似文献
10.
Changes in essential trace elements and heavy metals may affect the atherosclerotic state of patients on maintenance hemodialysis (HD). The aim of the study was to evaluate the relation between the serum levels of some trace elements and heavy metals (iron, zinc, manganese, copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio) and carotid artery intima-media thickness (CIMT) in HD patients. Fifty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. The serum levels of trace elements (iron, zinc, manganese, copper, and magnesium) and heavy metals (cobalt, cadmium, and lead) were measured by Atomic Adsorption Spectrophotometer (UNICAM-929). CIMT was assessed by carotid artery ultrasonography. The serum levels of iron, zinc, and manganese were lower; levels of copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio were higher in HD patients compared to controls. CIMT in HD patients were higher than the control group (0.64?±?0.11 vs 0.42?±?0.05, p?0.001). There was a significant negative correlation between CIMT and serum levels of zinc (r?=?-0.70, p?0.01), iron (r?=?-0.71, p?0.01), and manganese (r?=?-0.47, p?0.01), while there was a significant positive correlation between CIMT and serum levels of copper (r?=?0.63, p?0.01), magnesium (r?=?0.77, p?0.01), cobalt (r?=?0.63, p?0.01), cadmium (r?=?0.48, p?0.01), lead (r?=?0.38, p?0.01), and copper/zinc ratio (r?=?0.68, p?0.01). A linear regression analysis showed that serum levels of magnesium, cadmium, lead, and copper/zinc ratio were still significantly and positively correlated with CIMT. We propose that copper/zinc ratio, magnesium and toxic metals cadmium and lead are independent determinants of CIMT in maintenance HD patients without known atherosclerotic disease. 相似文献