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991.
Claudia J. P. Simons Agna A. Bartels-Velthuis Gerdina H. M. Pijnenborg Genetic Risk Outcome of Psychosis Investigators 《PloS one》2016,11(4)
ObjectiveStudies have linked cognitive functioning to everyday social functioning in psychotic disorders, but the nature of the relationships between cognition, social cognition, symptoms, and social functioning remains unestablished. Modelling the contributions of non-social and social cognitive ability in the prediction of social functioning may help in more clearly defining therapeutic targets to improve functioning.MethodIn a sample of 745 patients with a non-affective psychotic disorder, the associations between cognition and social cognition at baseline on the one hand, and self-reported social functioning three years later on the other, were analysed. First, case-control comparisons were conducted; associations were subsequently further explored in patients, investigating the potential mediating role of symptoms. Analyses were repeated in a subsample of 233 patients with recent-onset psychosis.ResultsInformation processing speed and immediate verbal memory were stronger associated with social functioning in patients than in healthy controls. Most cognition variables significantly predicted social functioning at follow-up, whereas social cognition was not associated with social functioning. Symptoms were robustly associated with follow-up social functioning, with negative symptoms fully mediating most associations between cognition and follow-up social functioning. Illness duration did not moderate the strength of the association between cognitive functioning and follow-up social functioning. No associations were found between (social) cognition and follow-up social functioning in patients with recent-onset psychosis.ConclusionsAlthough cognitive functioning is associated with later social functioning in psychotic disorder, its role in explaining social functioning outcome above negative symptoms appears only modest. In recent-onset psychosis, cognition may have a negligible role in predicting later social functioning. Moreover, social cognition tasks may not predict self-reported social functioning. 相似文献
992.
993.
江苏泗洪下草湾组系我国现知中中新统中发现松鼠化石种类最多,材料最丰富的一个层位.采自松林庄、双沟和郑集的91件标本,代表了五个属、种松鼠,其中有飞松鼠二种, Parapetaurista tenurugosa 和 Shuanggouia lui, 花栗鼠一种, Eutamias sihongentis, 树松鼠一种, Plesiosciurus sinensis,以及一种很可能为地松鼠的松鼠未定属、种, Sciuridae gen. et sp. indet..本文对上述松鼠进行了描述和对比,初步讨论了它们与欧洲和北美一些松鼠的关系,并根据松鼠组合的性质,对该动物群的时代作了估计. 相似文献
994.
Research Committee of the Scottish Society of Physicians 《BMJ (Clinical research ed.)》1971,4(5790):775-784
A trial is reported of the effects of giving clofibrate to prevent progression of pre-existing ischaemic heart disease. There were two groups randomly distributed between clofibrate (350 patients) and placebo (367 patients) regimens. The trial lasted about six years and was conducted in 19 hospitals in Scotland. The criteria of acceptance into the trial were precise and were monitored by one observer. The standards of diagnosis of events were defined and all protocols and electrocardiograms were read blind by one observer.Three categories of patients were admissible to the trial: (1) patients with one myocardial infarction (W.H.O. E.C.G. criteria) between 8 and 16 weeks before the start of the trial; (2) patients with angina of a duration of 3 to 24 months, provided their E.C.G. showed signs of myocardial ischaemia at rest or after exercise; and (3) patients with one recent myocardial infarction and pre-existing angina as defined above.There were fewer deaths in patients with angina (categories 2 and 3 above) treated with clofibrate than in those on placebo. The mortality in the former group was reduced by 62%, and this is a statistically significant difference. Clofibrate did not have any statistically significant effect in reducing the rate of non-fatal infarction in patients with angina or in those with myocardial infarction and pre-existing angina, though a beneficial trend was evident when both subgroups were combined (a 44% reduction compared with the placebo group). There was a significant reduction in all events (fatal and non-fatal) in patients with angina (“all anginas”) in the clofibrate-treated group; the rate was reduced by 53%.Clofibrate did not alter the overall mortality or morbidity rates in patients admitted to the trial with recent myocardial infarction without preceding angina of more than three months'' duration. In one subgroup there was a statistically significant adverse effect in the clofibrate-treated group. The lack of any overall effect in patients with myocardial infarction might be related to the unexpectedly low mortality rate (2·97%) in the placebo group; it is usually in the region of 4-9% per annum after first myocardial infarction.In patients categorized as “all anginas” there was significant reduction in events whether the initial serum cholesterol level was high (greater than 260 mg/100 ml) or normal. Clofibrate seemed to have a small but not significant beneficial effect in patients with myocardial infarction with initially high serum cholesterol levels, but was of no value in those with initially normal serum cholesterol levels. There was no significant relationship between the response or lack of response of serum cholesterol to clofibrate and the incidence of events either in patients with angina or in those with infarction.The main conclusion of this trial is that clofibrate had a beneficial effect in reducing mortality and, to a lesser extent, morbidity in patients who presented with angina (“all anginas”). This effect was independent of initial serum cholesterol levels or the extent to which serum cholesterol was lowered. The drug had no significant overall effect on prognosis in patients with myocardial infarction alone. 相似文献
995.
Rita Guttman with the technical assistance of Robert Barnhill 《The Journal of general physiology》1968,51(5):621-634
The lowering of external sodium raised both the constant quantity threshold, Qo, and the rheobase, Io, in both real space-clamped squid axons and the theoretical axon as computed on the basis of the standard Hodgkin-Huxley equations. In both real and theoretical axons the minimum intensity for excitability for short pulses, which occurs at about 15°C, was still present when low sodium replaced seawater. Low sodium did not affect the temperature dependence of the strength-duration relationship in the range, 5° to 25°C. The excitability of tetrodotoxin-treated real axons was found to be more temperature-dependent than that of normal real axons. Also the data on dosage-response to TTX of real axons fit the dose-response relationship of a hypothetical system in which one TTX ion binds reversibly to its receptor to produce a fraction of the inhibitory effect, the curve being identical to a simple adsorption isotherm. The Hodgkin-Huxley equations describe the broad outline of events occurring during excitation quite well. 相似文献
996.
The Effect of Insulin on the Distribution of Glucose between the Blood Plasma and the Liver 下载免费PDF全文
G. Hetenyi Jr. G. S. Arbus with the technical assistance of W. G. Layng. 《The Journal of general physiology》1962,45(6):1049-1063
In normal fasted rats whole liver tissue contains as much glucose as the blood plasma, i.e., the ratio of the concentrations is about unity. The concentration of glucose in hepatic intracellular water is about 1.2 times higher than in plasma water. In rats injected with insulin the concentration of glucose in the liver falls to a lesser extent than in the plasma: resulting in a ratio of concentrations higher than unity. If insulin hypoglycemia is prevented by the ingestion of glucose the concentration ratio is less than in hypoglycemic rats but still significantly above unity. In normal rats the specific activities of plasma and hepatic glucose do not differ significantly at 7.5, 15, and 30 minutes after the intravenous injection of C14-labeled glucose. In rats injected with insulin the specific activity of glucose is higher in the plasma than in the liver at 7.5 and 15 minutes, but not at 30 minutes following the injection of tracer. In insulin-treated hypoglycemic rats considerably higher concentrations of labeled glucose are found in hepatic intracellular than in plasma water. The penetration of C14-glucose from plasma into hepatic intracellular water is found to be fast. Excess insulin causes an accumulation of glucose within the liver cells by retaining newly formed glucose and by the taking up of glucose from the plasma against an existing concentration gradient. 相似文献
997.
施履吉 《分子细胞生物学报》1956,(1)
Chargaff(1951)分析各种生物去氧核糖核酸(以下简称 DNA)的化学组成,发现各种生物的 DNA 组成不同,同种生物各种组织的 DNA 组成相同。可是这些都是成长个体 DNA 的分析。虽然成长个体的组织是由胚胎发育分化而成,各种组织 DNA 相似文献
998.
一.引言谷类作物在开花以后,籽粒中大量堆积淀粉,一个多月可以增加几十倍,占植物总干重三分之一以上。因为淀粉的经济价值大,以及累积速度高,这个变化一直受着研究工作者的注意。在这一个过程中,那些酶起着主要的作用,它们的活力如何在变化,成了一个重要的问题。ax 等(Bach,Oparin 和 Wihner 1927)及(1951) 相似文献
999.
The Biological Mechanisms of Air Ion Action : II. Negative air ion effects on the concentration and metabolism of 5-hydroxytryptamine in the mammalian respiratory tract 总被引:2,自引:0,他引:2 下载免费PDF全文
Albert P. Krueger Richard F. Smith with the technical assistance of Eddie Reed 《The Journal of general physiology》1960,44(2):269-276
Negative air ions are shown to decrease 5-hydroxytryptamine concentrations in extirpated strips of rabbit trachea and in the respiratory tracts of living mice. An initial exposure of guinea pigs to (-) air ions causes a transient rise in urinary 5-hydroxyindoleacetic acid excretion which is not observed upon subsequent exposures. These findings are compatible with the hypothesis advanced earlier that (-) air ion effects depend on the ability of (-) ions to accelerate enzymatic oxidation of 5-hydroxytryptamine. 相似文献
1000.
Jack Myers With the Technical Assistance of Marian Cramer James Johnston 《The Journal of general physiology》1947,30(3):217-227
1. An oxidative assimilation of acetic add and glucose in darkness has been demonstrated in the green alga, Chlorella pyrenoidosa. From manometric experiments it has been shown that 1 mol (CH2O) per mol acetic add and 5 mols (CH2O) per mol glucose are produced. 2. The time required for complete utilization of a limited amount of acetic acid or glucose is not affected by illumination in the absence of carbon dioxide. 3. The time required for complete utilization of a limited amount of glucose is not affected by the simultaneous occurrence of photosynthesis. It must therefore be concluded that the accumulating product of photosynthesis cannot be glucose but must be some slowly respirable (storage) material. 4. Possible interrelationships between oxidative assimilation and photosynthesis may be further studied by following, in darkness and in light, the time course of oxidative assimilation of substrates which are possible intermediates in the two processes. 相似文献