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961.
962.
Insulin is necessary to produce an increase of plasma fibrinogen in rats submitted to tissue injury or ACTH administration. This increase is more significant when endogenous or exogenous excess of insulin is present, while in uninjured rats the absence or excess insulin does not modify plasma fibrinogen. 相似文献
963.
Hl. de Vries 《Cellular and molecular life sciences : CMLS》1948,4(9):357-358
Summary The influence of the temperature of the eye on the spectral distribution of its sensitivity was studied. The leading idea was that the small long-wave light quanta could only decompose a molecule of the photochemical substances if this molecule had already a sufficient thermal energy. One must therefore expect the sensitivity for long wavelengths to be higher at high temperatures; moreover this influence of temperature is most pronounced for the longest wavelengths. In the measurements the sensitivity for the wavelengths of 660 mµ and 730 mµ were comparedwith each other. In the accompanying figure the slit width of the apparatus at 660 mµ is shown as a function of temperature. The experimental points are close to the lines which were predicted by the theory. 相似文献
964.
L. Massart G. Peeters J. de Ley R. Vercauteren 《Cellular and molecular life sciences : CMLS》1947,3(4):154-155
Résumé MgCl2 et d'autres sels à des concentrations définies protègent la respiration de la levure de boulangerie contre l'action inhibitrice de colorants basiques. 相似文献
965.
966.
Benzodiazepine impairs and beta-carboline enhances performance in learning and memory tasks 总被引:3,自引:0,他引:3
P Venault G Chapouthier L P de Carvalho J Simiand M Morre R H Dodd J Rossier 《Nature》1986,321(6073):864-866
Benzodiazepines are widely used anxiolytics and anticonvulsants, and their potent sedative properties are routinely used in presurgical anaesthesia. However, they are also known to induce a strong anterograde amnesia in patients. Specific benzodiazepine antagonists have recently been described, some of which have intrinsic pharmacological properties that are opposite to those of benzodiazepines. These have been called inverse agonists and they have been shown to be proconvulsant or convulsant whereas benzodiazepines are anticonvulsants. Inverse agonists are also anxiogenic rather than anxiolytic. Since benzodiazepines induce anterograde amnesia, we have investigated the possibility that inverse agonists might also have an opposite effect for this property and so enhance acquisition (learning) and (or) retention (memory). We report here that, in three different animal models, an inverse agonist of the beta-carboline group, methyl beta-carboline-3-carboxylate (beta-CCM), enhances animal performance in three different tasks used to investigate learning and memory. 相似文献
967.
Gerard de Zeeuw 《Systemic Practice and Action Research》1993,6(2):155-172
Connections between people and groups are growing more frequent and more intense. Cultural events, changes in laws, activities of organizations, and new ideas elsewhere affect one's own decisions and activities more and more. This development has strong implications for the way people can increase their competence and how they can affect what happens to their own community or geographical area. In this paper consequences are considered for a special type of tool, the so-called problem language, that appears to be intimately entwined with many other tools in operations research, cybernetics, and systems research. The language appears most adequate in situations where boundaries can be found such that external events have minimal impact on what happens inside those boundaries. The change in connectivity makes finding such boundaries less and less probable. This suggests looking for another language, to structure the processes necessary when one intends to overcome difficulties that cannot be represented and solved as problems. A language of access is proposed, derived partly from studies in areas where it has never been possible to find boundaries as indicated. Within the framework of this language one can derive methods of externalization that imply speeding up flows of information in a shared workspace or shared information space. Their implementation is greatly facilitated—or even made possible at all—by recent developments in information technology. 相似文献
968.
Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study 总被引:2,自引:0,他引:2
JA Mattison GS Roth TM Beasley EM Tilmont AM Handy RL Herbert DL Longo DB Allison JE Young M Bryant D Barnard WF Ward W Qi DK Ingram R de Cabo 《Nature》2012,489(7415):318-321
Calorie restriction (CR), a reduction of 10–40% in intake of a nutritious diet, is often reported as the most robust non-genetic mechanism to extend lifespan and healthspan. CR is frequently used as a tool to understand mechanisms behind ageing and age-associated diseases. In addition to and independently of increasing lifespan, CR has been reported to delay or prevent the occurrence of many chronic diseases in a variety of animals. Beneficial effects of CR on outcomes such as immune function, motor coordination and resistance to sarcopenia in rhesus monkeys have recently been reported. We report here that a CR regimen implemented in young and older age rhesus monkeys at the National Institute on Aging (NIA) has not improved survival outcomes. Our findings contrast with an ongoing study at the Wisconsin National Primate Research Center (WNPRC), which reported improved survival associated with 30% CR initiated in adult rhesus monkeys (7–14?years) and a preliminary report with a small number of CR monkeys. Over the years, both NIA and WNPRC have extensively documented beneficial health effects of CR in these two apparently parallel studies. The implications of the WNPRC findings were important as they extended CR findings beyond the laboratory rodent and to a long-lived primate. Our study suggests a separation between health effects, morbidity and mortality, and similar to what has been shown in rodents, study design, husbandry and diet composition may strongly affect the life-prolonging effect of CR in a long-lived nonhuman primate. 相似文献
969.
Rotation in Correspondence Analysis 总被引:1,自引:1,他引:0
In correspondence analysis rows and columns of a nonnegative data matrix are
depicted as points in a, usually, two-dimensional plot. Although such a two-dimensional
plot often provides a reasonable approximation, the situation can occur that an approximation
of higher dimensionality is required. This is especially the case when the data
matrix is large. In such instances it may become difficult to interpret the solution. Similar
to what is done in principal component analysis and factor analysis the correspondence
analysis solution can be rotated to increase the interpretability. However, due to the various
scaling options encountered in correspondence analysis, there are several alternative
options for rotating the solutions. In this paper we consider two options for rotation in
correspondence analysis. An example is provided so that the benefits of rotation become
apparent. 相似文献
970.
在对割煤工序和放煤工序详细分析的基础上,提出了通过优化采煤机割煤速度实现优化综放采场采放工艺参数的新方法.认为采煤机合理切割速度是联系综放采场各工序的桥梁,只要输入煤层条件与装备条件,便可确定最优工艺参数,优化结果充分体现了主观因素与客观条件的有机统一.通过对兖矿集团兴隆庄煤矿5318综放面工艺参数优化,实现了日产平均1.2万t,年产426万t的全国高产高效生产水平.图3,表2,参5. 相似文献