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991.
镇原杏仁营养成分分析 总被引:1,自引:0,他引:1
镇原杏仁中除含具药用价值的苦杏仁甙(Amygdalin)外,还富含人体需要的营养物质。油的含量为50.1%,由8种脂肪酸组成,油酸和亚油酸总含量为94.4%。油中含有 V_A.V_(DS).V_E.V_(B17)等维生素,其中 V_(D3)含量高达5.01mg/100g。杏仁粉中含有16种氨基酸,人体必需的8种氨基酸都有,全氮为8.31%。同时还含有水溶性和脂溶性维生素11种,微量元素19种. 相似文献
992.
Three groups (14 rats each) were fed one of the following diets for 8 wks: a control purified basal diet containing 12 ppm zinc, 5 ppm copper, and 35 ppm iron; the basal diet with less than 2 ppm zinc; or the basal diet supplemented with 1000 ppm zinc. Rats fed the zinc-deficient diet had decreased weight gain, moderate polydipsia, and intermittent mild diarrhea. The zinc-supplemented rats had a cyclical pattern of food intake and weight loss from weeks 5 to 8. Tissue concentrations suggest that zinc and copper were not mutually antagonistic with chronic dietary imbalances. If tissue element concentrations reflected intestinal uptake, then competition and/or inhibition of intestinal uptake occurred between zinc and iron. The fluctuations in tissue element concentrations that occurred with increased duration of the study were at variance with previous studies of shorter time periods. The dietary proportions of zinc, copper, and iron appear to influence zinc, copper, and iron metabolism at the intestinal and cellular transport levels over a given period of time. 相似文献
993.
Yongpeng Tong Yongping Zhang Yaoliang Xu Jingyi Rui Minqian Li Cuiying Shen Zhongming Xiao Jinxin Hong 《Biological trace element research》1991,29(1):31-34
Gastric, hepatic, and pulmonary cancer cell lines, and the third passage of normal gastric and pulmonary cell lines were analyzed by proton induced X-ray emission (PIXE) method. The contents of element Sr, Ca, Fe, Zn, P, K, Cu, and As in the cell lines were determined. The Sr, Ca, Fe, Zn, and As contents in cancer cell lines were significantly lower than those in the normal cell lines (p less than 0.05), whereas there were no significant differences for the P, K, and Cu contents (p greater than 0.1). The results suggest that the need of some essential elements has been diminished in cancer cell proliferation. 相似文献
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The effects of adrenalectomy (ADY) and of replacement therapy using a mineralocorticoid, deoxycorticosterone (DOC) and a glucocorticoid,
dexamethasone (DEX) on the tissue distribution of elements in the rat, were studied under semichronic conditions. The elements,
Na, K, Ca, Mg, Fe, S, P, Rb, Sr, Mn, Cu, and Zn were determined in whole blood, plasma, brain liver, kidney, heart, skeletal
muscle, spleen, thymus, and bone. Additionally Mo was determined in kidney and liver and Ba in bone. ADY modified concentrations
of all elements tested. Small changes were observed for K, Mg, Ca, S, and P, whereas much larger changes were noted for Na,
Rb, and Sr. Cu, Zn, and Fe were mainly modified in liver and kidney, organs involved in storage and/or elimination. The consequences
of ADY were corrected fairly well by DEX for Mg, Mn, Ca, Cu, and Mo; by DOC for Na and K, and by the two corticoids for Zn,
Fe, Sr, and Rb. This study revealed that corticoids, mainly glucocorticoids, play an important role in the plasma and tissue
balance of elements. It is suggested that these results may have a pathological and clinical significance. 相似文献
998.
Element interactions in forest ecosystems: succession,allometry and input-output budgets 总被引:3,自引:3,他引:0
Element interactions within forests differ from those in other major ecosystems for three major reasons: — a greater allocation of carbon to structural material; — a greater element storage within biomass; and — the diversity of carbon- and nutrient-containing metabolites produced. The most important of these differences is structural material, which can lead to C: element ratios in biomass (as a whole) 100 × greater than those in unicellular organisms. Stand allometry causes the amount of carbon stored and C:element ratios in biomass to change in predictable ways in the course of secondary succession. Such changes affect microbial dynamics and C: element interactions within soils. Bicarbonate, organic acids, nitrate, phosphate, and sulfate are major anions within forest soils: they control leaching of both anions and cations. Biotic interactions of C, N, P, and S during both uptake and mineralization control the potential for production of these anions within forests, and geochemical interactions regulate their mobility and loss. 相似文献
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Radiotracers injected as soluble salts into 1.2 m3 limnocorrals in a shallow dystrophic lake were transported rapidly (2 to 12% d–1) from the water to the bottom sediments. Removal rates of most contaminants declined after 14 days. Tracers were removed from the water much more rapidly than stable element analogs present naturally. After 3 weeks Am, Co, Ra, Hg, Sn and Fe activities on the enclosure walls were greater than 15% of the activity in the water. However, activity on the walls was a small fraction (< 6%) of the total amount of tracer injected. Particle fluxes inside the corrals were lower and much less variable than those measured outside. This difference appears to result from greater resuspension of bottom sediments in the lake than in the enclosures. Both particle-bound and soluble tracers were measured in cores of bottom sediments. Tracer sorption onto particles, diffusion into the bottom sediments, and uptake on the plastic enclosure walls were rapid and reversible. Tracer kinetics were very reproducible in replicate enclosures, providing a simple, experimental system in which limnological conditions can be manipulated. Loss rates and distributions of stable isotopes and radioisotopes can be used to develop and test a general model of element transport applicable to both short and long term analyses. 相似文献