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991.
X. Gual-Arnau 《Biometrical journal. Biometrische Zeitschrift》1997,39(5):627-635
Given a cone around a curve β in IR3 it is shown that there is no relation between the curvature of β and the volume of the cone but, in contrast to the volume, the surface area of the cone depends, albeit rather weakly, on the curvature of β. The geometric meaning of the stereological formulae when applied to cones is considered and it is noted that stereological methods to estimate the surface area of a cone need to be extremely precise to provide information concerning curvature or tortuosity. 相似文献
992.
993.
《Fish & shellfish immunology》2014,36(1):46-51
The present study investigated the effects of different dietary nettle (Urtica dioica) levels on biochemical, hematological and immunological parameters in beluga (Huso huso). Fish were divided into 4 groups before being fed for 8 weeks with 0%, 3%, 6% and 12% of nettle. The blood samples were collected on week 4 and 8. The use of nettle did not significantly change the mean cell volume, mean cell haemoglobin, lymphocytes, eosinophils, albumin, glucose, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and lysozyme activity on week 4 and 8. After 4 weeks, the total red blood cell (RBC) and hematocrit (Ht) showed a significant increase in 12% nettle group compared to the 3% nettle and control groups but haemoglobin (Hb) had a significant change in 12% nettle compared to the control. At the same time was not found a significant change in the mean cell haemoglobin concentration (MCHC), total white blood cell (WBC), neutrophils, respiratory burst activity (RB), total immunoglobulin (Ig) and total protein (TP), triglyceride (Tri) and cholesterol (Chol). After 8 weeks, the fish treated with nettle exhibited significantly increase in neutrophil and Hb levels compared to the control and between treatment groups, 12% nettle group shown the highest Hb while RBC and Hct values significantly rose in fish fed by 12% compared to the control. Supplementing 6% and 12% nettle increased the WBC and MCHC compared to the other groups. The group fed 12% showed a highly significant difference in RB, TP and Ig after 8 weeks. However, Tri and Chol were significantly decreased in the juvenile beluga fed by the 6% and 12% nettle diet compared to the other groups. The results suggest that by using this herb there will be an improvement in hemato-biochemical parameters and immune function of juvenile beluga. 相似文献
994.
995.
When a population budget must be obtained from censuses based on replicated, sacrificed cultures, it is difficult to obtain estimates of transition probabilities and of the errors of such estimates, because there is no logical basis for pairing successive census counts. In a study of this nature estimating a population budget of immature stages of the housefly, the problem was solved by a randomization treatment of the original census results obtained at two densities. One hundred randomly generated census matrices over all census times for each density were smoothed to remove the effects of sampling error and a population budget constructed according to defined rules. Transition probabilities computed from the population budget were plotted on triangular coordinate paper and mean probabilities, 95% confidence regions for these means, and 95% equal frequency ellipses computed. All computations and the graphing of the results were carried out on a digital computer. The computer program, available from the authors, is written in FORTRAN IV and could be easily modified for similar studies. 相似文献
996.
K. L. Sahrawat 《Plant and Soil》1980,55(2):181-187
Summary The nitrogen-supplying power of eight Philippine rice soils was measured by consecutively growing six crops of IR 32 rice under flooded conditions in a greenhouse pot experiment. The dry matter yields or nitrogen uptake of rice were found to be highly positively correlated with the organic carbon and the total nitrogen contents of the soils, as well as with the amounts of ammonium released during an anaerobic incubation test at 30°C for 2 weeks.The results of the study bring out the usefulness of simple tests like organic carbon content and total nitrogen content of soils for predicting the nitrogen-supplying power to lowland rice. 相似文献
997.
Joseph E. Odencrantz John M. Farr Charles E. Robinson 《Soil & Sediment Contamination》1992,1(2):159-182
The California Leaking Underground Fuel Tank Field Manual (LUFT Manual; WRCB, 1989) is used by the regulatory community, consultants, and industry in California to determine acceptable cleanup concentration goals for the remediation of hydrocarbon‐affected soils. The LUFT methodology is a semiquanitative approach that uses rating tables that consider the effects of local precipitation and the depth to ground water from the deepest affected soils, as well as anthropogenic and geologic factors. The latter factors are evaluated subjectively, with only the effects of local precipitation and depth to ground water accounted for quantitatively. To assess the effects of these variables on the hydrocarbon concentrations that could be left in soil while protecting ground water quality, the state of California performed modeling using SESOIL and AT123D. The results from a small number of simulations covering a very narrow range of input parameter values were then extrapolated to form the LUFT Manual rating tables, which cover ranges in precipitation and depth to ground water of 0 to 40 in. per year and 5 to 150 ft, respectively. Although the use of these tables generally results in conservative cleanup level determinations, the extrapolation method used and the lack of consideration for extremely sensitive input parameters (other than precipitation and depth to ground water) in the development of the tables calls into question their validity. A sensitivity analysis on the model input parameters is presented that highlights several critical input parameters that greatly affect cleanup concentration determinations. The sensitivity analysis shows that certain parameters that were fixed at conservative levels for the development of the LUFT Manual rating tables (e.g., biodegradation rate and soil organic carbon content) are more sensitive than precipitation and the depth to ground water. In many cases, site‐specific analysis will thus yield higher soil cleanup concentrations that are still protective of water quality. In addition, in some instances the cleanup concentrations in the LUFT Manual tables are not protective of water quality. To provide a firm basis for soil cleanup‐level determinations, site‐specific analysis is recommended whenever significant quantities of soil may require remediation. This will provide more cost‐effective remediation and greater assurance of water quality protection. 相似文献
998.
V. Elayne Arterbery William A. Pryor Long Jiang Shelley S. Sehnert W. Michael Foster Ross A. Abrams Jerry R. Williams Moody D. Wharam Jr. Terence H. Risby 《Free radical biology & medicine》1994,17(6):569-576
Total body irradiation (TBI) is used therapeutically for treatment of leukemias and other malignancies of the hemopoietic system. Ionizing radiation produces oxygen free radicals that contribute to cytotoxicity. Breath collected from one patient undergoing therapeutic TBI showed measurable changes in levels of ethane during treatment. Breath ethane is a marker of lipid peroxidation of n-3 fatty acids. The TBI treatment involved 4 days of irradiation. The largest changes in breath ethane occured on Day 2. The increased levels of breath ethane on Day 2 were correlated to clinical manifestations of toxicity. The correlation of the onset of gastrointestinal side effects with higher levels of breath ethane suggests that breath ethane may be a clinically useful measure of the toxicity of various TBI fractionation treatment protocols currently in use at different medical centers. The levels of breath ehtane on the other days of treatment were lower, suggesting that the oxidative-antioxidative balance of the patient may be important in protection against free radical mediated injury. These results for a single patient suggest that breath ethane may be a promising approach to elucidate the role of antioxidants in clinical TBI and should be extended for verification to a larger volunteer patient population. 相似文献
999.
The effects of mannitol and salinity stresses on growth and biochemical accumulations in lemon balm 下载免费PDF全文
The effects of saline irrigation water and mannitol on the growth and content of essential oil, photosynthetic pigments, soluble sugars, proline, Na, macroelements (N–P–K) and microelements (Mg–Zn–Fe–Mn) of lemon balm (Melissa officinalis L.) plants were investigated. Saline irrigation water decreased certain growth characters (total leaf area, leaf number, and total fresh and dry mass). The photosynthetic pigments (chlorophylls a and b, total carotenoids) and mineral content (N–P–K–Mg–Zn–Fe–Mn) also decreased as saline irrigation water level increased. Saline irrigation water promoted the accumulation of essential oil content and its main components (citronellal, citronellol and geranyl acetate) as well as total soluble sugars, proline and Na+ contents. The plants treated with saline irrigation water × mannitol resulted in higher plant growth, essential oil, total soluble sugars, proline, macro and micronutrient values than those treated with saline irrigation water alone, photosynthetic pigments and Na demonstrated an opposite trend. 相似文献
1000.
《Cryobiology》2010,61(1):22-83
Systemic cryostimulation is useful treatment, both in sport and medicine, during which human body is exposed to very low, cryogenic temperature (below −100 °C). Although there exists some evidence of its beneficial effect in biological regeneration, so far it has not been unequivocally determined if the positive effect of repeated stimulations depends on their number in a series. The aim of this research was to estimate the influence of 5, 10 and 20 sessions of 3 min-long exposures to cryogenic temperature (−130 °C) on the lipid profile in physically active men. Sixty-nine healthy volunteers participated in the study. The blood samples were taken in the morning, after overnight fasting, before the first cryostimulation session, and the following morning after the last one (5th,10th, 20th).In serum specimens the concentration of total cholesterol (TCh), HDL cholesterol and triglicerydes were determined using enzymatic methods. LDL cholesterol level was calculated using Friedewald formula. The changes in lipid profile (LDL decrease with simultaneously HDL increase) occurred after at least 10 sessions of cryostimulation. 相似文献