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41.
42.
F J Hurtado A M Gutierrez N Silva E Fernandez A E Khan G Gutierrez 《Journal of applied physiology》1992,72(5):1895-1901
We compared the hemodynamic and metabolic alterations produced in rabbits by similar decreases in cardiac output created by inflating a balloon placed in the right ventricle (n = 6) with those produced by an intravenous bolus of Escherichia coli lipopolysaccharide (LPS; SEP group; n = 6). We measured O2 consumption (VO2), O2 transport (TO2), and O2 extraction ratio (ERO2) for the whole animal and also for the left hindlimb. Both groups experienced similar decreases in cardiac output, systemic TO2, and VO2 and similar increases in ERO2. For the hindlimb, TO2 was similar, but VO2 and ERO2 were lower for the SEP group 30 min after LPS administration (P less than 0.05); however, this difference disappeared during the remainder of the experiment. Arterial lactate concentration was greater (P less than 0.05) for the SEP group. There were no differences in skeletal muscle PO2, measured with a multiwire surface electrode, or in cardiac and skeletal muscle concentrations of high-energy phosphates. We hypothesize that a direct effect of LPS on cellular metabolism may have resulted in greater arterial lactate concentration for the SEP group. 相似文献
43.
R Fischer-Colbrie J Gutierrez C M Hsu A Iacangelo L E Eiden 《The Journal of biological chemistry》1990,265(16):9208-9213
Secretogranin II is a very acidic, tyrosine-sulfated protein found in secretory granules of cells belonging to the diffuse neuroendocrine system. It gained more general importance recently as a universal immunohistochemical marker for endocrine neoplasms. Sequence information was obtained from secretogranin II isolated from bovine anterior pituitaries, allowing the isolation of cDNA clones and deduction of its primary structure. Bovine secretogranin II is a 586-amino acid protein of 67,455 Da which is preceded by a signal peptide of 27 residues and contains 9 pairs of basic amino acids in its sequence which are used as potential cleavage sites for generation of physiologically active peptides. Moderately abundant mRNA levels were found in adrenal medulla, pituitary, hippocampus, and caudate. Secretogranin II message was absent from parathyroid gland, adrenal cortex, kidney, liver, and spleen. Depolarization of isolated chromaffin cells by various secretagogues significantly up-regulated secretogranin II mRNA levels by mechanisms distinct from those established for chromogranins and neuropeptides, components maintained along with secretogranin II in neuroendocrine storage vesicles. 相似文献
44.
Trehalose in yeast,stress protectant rather than reserve carbohydrate 总被引:37,自引:1,他引:36
Andres Wiemken 《Antonie van Leeuwenhoek》1990,58(3):209-217
Trehalose and glycogen are generally regarded as the two main reserve carbohydrates in yeast. However, several lines of evidence suggest that trehalose does not primarily function as a reserve but as a highly efficient protecting agent to maintain strutural integrity of the cytoplasm under environmental stress conditions. 相似文献
45.
Robert M. Malina John H. Himes Carol Dutton Stepick Francisca Gutierrez Lopez Peter H. Buschang 《American journal of physical anthropology》1981,54(3):327-336
Weight, stature, arm circumference, and the triceps skinfold were measured in 1,410 school children, 6 through 14 years of age, from two urban colonias in the city of Oaxaca de Juarez (n = 479), and from two rural Ladino (n = 467) and two rural Zapotec (n = 464) communities in the Valley of Oaxaca in southern Mexico. Children from rural Ladino communities and urban colonias are significantly taller, heavier, and more muscular than children in rural Zapotec communities. The differences between rural Ladino and urban colonia children favor the former, particularly for weight and stature. These observations thus suggest (1) that children in the rural, indigenous communities in the Valley of Oaxaca are relatively undernourished compared to children in Ladinoized and urban communities, and (2) that rural-to-urban migration does not necessarily result in improved growth status. 相似文献
46.
Robert M. Malina John H. Himes Carol Dutton Stepick Francisca Gutierrez Lopez Peter H. Buschang 《American journal of physical anthropology》1981,55(2):269-280
Weight, stature, arm circumference, and the triceps skinfold were measured in 1,410 school children, 6 through 14 years of age, from two urban colonias in the city of Oaxaca de Juarez (n = 479), and from two rural Ladino (n = 467) and two rural Zapotec (n = 464) communities in the Valley of Oaxaca in southern Mexico. Children from rural Ladino communities and urban colonias are significantly taller, heavier, and more muscular than children in rural Zapotec communities. The differences between rural Ladino and urban colonia children favor the former, particularly for weight and stature. These observations thus suggest (1) that children in the rural, indigenous communities in the Valley of Oaxaca are relatively undernourished compared to children in Ladinoized and urban communities, and (2) that rural-to-urban migration does not necessarily result in improved growth status. 相似文献
47.
Candida lipolytica was grown continuously on n-hexadecane as the main source of carbon. A transient continuous-culture experiment was also conducted to investigate hydrocarbon-limited growth; the hydrocarbon feed flow rate was stopped for several hours and then resumed at a reduced steady-state flow rate. Interfacial tension, Sauter mean diameter, pseudosolubility, fraction of cells in the aqueous phase, oil-phase volume fraction, and cell concentration were measured to characterize the system. The microorganisms appear to utilize both the submicron drops and the microscopic drops. The effects of interfacial tension, pseudosolubility, and unoccupied interfacial area on the kinetics of hydrocarbon fermentation are discussed here. A conceptual model for hydrocarbon uptake is presented and discussed. 相似文献
48.
49.
Katrina Laks Tiina Kirsipuu Tuuli Dmitrijeva Andres Salumets Peep Palumaa 《The protein journal》2016,35(3):171-176
Biological fluid sample collection often includes the risk of blood contamination that may alter the proteomic profile of biological fluid. In proteomics studies, exclusion of contaminated samples is usually based on visual inspection and counting of red blood cells in the sample; analysis of specific blood derived proteins is less used. To fill the gap, we developed a fast and sensitive method for ascertainment of blood contamination in crude biological fluids, based on specific blood-derived protein, hemoglobin detection by MALDI-TOF MS. The MALDI-TOF MS based method allows detection of trace hemoglobin with the detection limit of 0.12 nM. UV-spectrometry, which was used as reference method, was found to be less sensitive. The main advantages of the presented method are that it is fast, effective, sensitive, requires very small sample amount and can be applied for detection of blood contamination in various biological fluids collected for proteomics studies. Method applicability was tested on human cerebrospinal and follicular fluid, which proteomes generally do not contain hemoglobin, however, which possess high risk for blood contamination. Present method successfully detected the blood contamination in 12 % of cerebrospinal fluid and 24 % of follicular fluid samples. High percentage of contaminated samples accentuates the need for initial inspection of proteomic samples to avoid incorrect results from blood proteome overlap. 相似文献