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201.
Intrathecal cholecystokinin interacts with morphine but not substance P in modulating the nociceptive flexion reflex in the rat 总被引:6,自引:0,他引:6
The effect of intrathecal (IT) cholecystokinin (CCK), substance P (SP) and morphine (MO) on spinal cord excitability was studied in decerebrate, spinalized rats. CCK had a weaker facilitatory effect on the nociceptive flexion reflex than SP. The possible functional significance of the coexistence of CCK and SP in neurons projecting to the spinal cord was tested by coadministration of the two peptides. At the doses tested no synergistic interaction on the reflex was found with CCK and SP. IT MO caused a brief enhancement followed by a prolonged depression of the reflex. A high dose of CCK injected prior to MO increased the facilitatory effect and decreased the depressive effect of the opiate on the reflex. The effect of desulfated (D) CCK was similar to CCK but at a higher dose. Naloxone (NAL) had a similar effect as CCK when administered prior to MO. The MO-induced depression of the reflex was readily reversed by NAL, but not by CCK. The results indicate that CCK may prevent the inhibitory effect of MO on spinal cord excitability to nociceptive stimulation, but does not reverse it. CCK may alter the balance of excitation-inhibition between various types of dorsal horn interneurons that are involved in the transmission of nociceptive information. 相似文献
202.
Studies on the effect of different content of vitamin B2 (alimentary deficiency, additional administration) in the rat organism on the activity of enzymes participating in the metabolism of foreign substances and on the inducing effect of phenobarbital have shown that vitamin B2 to a considerable extent controls the activity of flavin-containing enzymes participating in the metabolism of xenobiotics (D-amino acid oxidase, xanthine and aldehyde oxidases, NADH- and NADPH-reductase activity of neotetrazolium) and a number of enzymes for which flavins do not play the role of prosthetic group (esterases aldehyde and formaldehyde dehydrogenases, demethylase and hydroxylase). Different content of vitamin B2 in animal organism also influences the action of phenobarbital, an inductor of xenobiotics metabolism, and the acetanilide biotransformation rate. 相似文献
203.
V I Kocherga N V Nesterenko Z D Vorobets L K Kurchenko M D Kurski? 《Ukrainski? biokhimicheski? zhurnal》1987,59(1):61-66
The effect of membrane potential on the passive 45Ca2+ uptake by cardial sarcolemmal vesicles was investigated. Membrane potentials were generated by the K+ gradient in the presence of valinomycin and were measured using fluorescent dye diS-C3-(5). It was shown that the 45Ca2+ influx into vesicles increased twice after membrane depolarization. Evaluation of the 45Ca2+ influx over a wide range of membrane potentials produced a profile similar to that of current-voltage relationships for single calcium channels in isolated cardiomyocytes. Passive 45Ca2+ transport was inhibited by 1 mM Cd2+ and Co2+. It is suggested that the voltage-dependent Ca2+ influx into vesicles occurs through Ca2+-channels. 相似文献
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205.
The paper presents data on variations in the level of serous immunoglobulins (Ig M and Ig G classes), immunocompetent T- and B-lymphocytes in lymphoid organs (spleen, mesenteric, portal and mediastinal lymph nodes) and specific antiparasitic antibodies in guinea pigs during the dynamics of experimental ascariasis. 相似文献
206.
K J Rorig Z Ruben S N Anderson 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1987,184(2):165-171
Disobutamide (D), an antiarrhythmic cationic amphiphilic amine (CAA), was withdrawn from clinical testing when clear cytoplasmic vacuoles (CCV) were found in the rat and dog during toxicity studies. To delineate the structural determinants of amines that induce CCV, we exposed cultured rat urinary bladder carcinoma and rabbit aorta muscle cells to numerous cationic drugs and chemicals and examined cells by phase light microscopy. The cationic moiety of these CAA was responsible for the induction of CCV. The very potent inducers were compounds that had two strongly basic amine (cationic) centers. The bis tertiary amines were particularly potent inducers. Aliphatic diamines of minimal lipophilicity-induced CCV, thus showing that an "amphiphilic" structural feature, though present in many CAA drugs, is not necessary for CCV induction. The distance between the two cationic centers was irrelevant to the induction of CCV. These results support the concept that CCV are a manifestation of intracellular (e.g., intralysosomal) drug storage. These structural delineations will be useful in future drug design and for further understanding of drug-cell interactions. Based on these findings, we were able to synthesize an antiarrhythmic CAA which did not induce CCV. 相似文献
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209.
The addition of a cytoplasmic fraction, isolated from cells 3h after irradiation of mice, to exposed or intact thymocyte nuclei causes a 2- or 3-fold acceleration of chromatin degradation in the nuclei incubated in conditions optimum for activity of Ca2+,Mg2+-dependent endonuclease to be manifest. In contrast to thymocytes, no chromatin degradation products are found in liver cells of irradiated mice. The cytoplasmic fraction isolated from hepatocytes of irradiated animals fails to activate chromatin degradation in thymocyte nuclei. 相似文献
210.
Z Kleinrok M Sieklucka-Dziuba A Sek E Rodziewicz U Latus 《Acta physiologica Polonica》1987,38(6):477-482
In experiments on male Albino-Swiss mice weighing 18-22 g insulin given in doses of 2 i.u./kg caused no change in the time of reaction to pain, while the same dose administered daily for 7 days potentiated the analgesic action of morphine (3 mg/kg s.c.). Glucose caused no change in this effect of insulin. After 14 days of insulin treatment the time of reaction to pain in the animals subjected to the action of morphine returned to its initial value. Twenty-four hours after the last administration of morphine the level of gamma-aminobutyric acid (GABA) was found to be decreased in the animals receiving insulin with glucose. These results suggest that the central action of insulin is dependent not only on hypoglycaemia produced by it, but may be due also to its direct action on the central structures and an indirect action mediated by its effect on other neurotransmitter systems. 相似文献