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991.
Our new finding of de novo synthesis and secretion of C3 by both murine peritoneal macrophages and polymorphonuclear leukocytes (PMN) was confirmed by the incorporation of [35S]methionine into C3 molecules and their complete inhibition by cycloheximide. The methods of secretion of C3 from these two types of cells were compared by examining the C3 contents in their culture supernatants. Completely different modes of secretion were observed, i.e. although macrophages synthesize and secrete C3 constitutively, PMN has a mechanism to store the already synthesized C3 in the cell and secrete it in response to stimuli. Protein kinase C (PKC) activators, e.g. 12-O-tetradecanoyl-phorbol 13-acetate, dioctanoyl glycerol, and mezerein, as well as calcium ionophore A23187 stimulate the secretion of C3 from PMN. These results suggest the involvement of PKC and the calmodulin pathway. A very sensitive method for measuring C3 activity was developed which enabled us to show for the first time that C3 secreted by PMN had opsonizing activity and that particles cultured with PMN were phagocytosed effectively. 相似文献
992.
硝酸铋与丙磺舒合用对顺铂肾毒性的防护作用 总被引:1,自引:0,他引:1
毒性剂量的顺铂(CP30μmol·kg-1ip)可引起血尿素氮(BUN)升高。硝酸铋(BN)5μmol·kg-1于CP前48和24hse,丙磺舒(Pro)700μmol·kg-1于CP前15,1h及CP后5hig,或BN与Pro二者半量合用,按上述给药,均能抑制CP引起的BUN升高,尤以BN+Pro组抑制作用显著。肾脏光镜和电镜标本显示,CP使肾小管受损严重;BN组,Pro组和BN+Pro组均使CP引起的肾小管受损减轻,尤以BN+Pro组减轻明显。BN2.5-20μmol·kg-1剂量依赖性地诱导小鼠肾脏金属硫蛋白合成。Pro可使CP后24b肾铂含量明显降低;Pro或Pro+BN使尿铂累积排出量增加,血浆铂浓度降低。提示PFO防护CP肾毒性与其减少肾铂分布,增加尿铂排出有关。 相似文献
993.
Michael Irwin 《Stress and health》1988,4(2):95-103
Clinical studies have demonstrated that measures of cell-mediated immune function are altered in bereaved persons and depressed patients. This review article focuses on our recent observations of changes in T cell subpopulations and natural killer cytotoxicity in women undergoing adverse life events including conjugal bereavement. A reduction in natural cytotoxicity has also been found in depressed patients. The mechanism by which psychologic states might influence immune function is discussed. 相似文献
994.
Summary A series of in vivo experiments were undertaken, relating functional (motor activity, body temperature), dopamine (DA) receptor binding and neurochemical (catecholamine synthesis and utilization, DA release) aspects of the pharmacology of SCH 23390 in the rat.The compound inhibited the locomotor hyperactivity, but not the hypothermia, induced by the potent DA stimulant DP-5,6-ADTN. Interstingly, SCH 23390 simultaneously failed to displace DP-5,6-ADTN from its binding sites in the rat striatum—used as a direct in vivo biochemical index of DA (D-2) receptor interaction. The spontaneous locomotion in non-pretreated rats was likewise inhibited by SCH 23390. The locomotor-suppressive action, but not the DP-5,6-ADTN-displacing capcity of the D-2 blocker haloperidol was significantly enhanced by SCH 23390, suggesting that motility can be suppressed by either enhanced D-1 or D-2 (postsynaptic) receptor blockade, but also that the D-1 and D-2 sites involved may be physically distinct.SCH 23390 only slightly altered in vivo neurochemical of DA synthesis, release and nerve-impulse flow, indicating that, while similar in suppressing dopaminergic behaviour, the D-1 antagonist is less effective than traditional neuroleptics as an activator of DA neuronal feedback mechanisms. The weak increases of DA synthesis and release nonetheless obtained were equal in magnitude (30–40%) in the limbic vs. striatal brain areas; also in this respect, SCH 23390 thus differs from classical neuroleptics, which generally display more marked effects in the striatum than in limbic tissue.No major changes in the in vivo indices of NA synthesis and utilization (or in 5-HT synthesis) were found after SCH 23390 administration, by and large supporting the DA receptor specificity of the compound.In summary, the studies demonstrated that SCH 23390 can offset and accentuate, respectively, behavioural consequences of D-2 receptor stimulation and blockade. Importantly, at the same time no direct interaction at the level of D-2 DA receptor sites in the striatum was detected. Only slight, D-2 antagonist-like, changes in neurochemical indices of dopaminergic activity were observed after D-1 receptor blockade by means of SCH 23390. With regard to DA agonist hypothermia, SCH 23390 was without effect per se, but (at a high dose) attenuated the action of the D-2 antagonist haloperidol. The observations may indicate that the complex interactions between central D-1 and D-2 receptor-controlled mechanisms that influence behaviour, neurochemistry, and possibly autonomic nervous expression, are not identical. 相似文献
995.
996.
997.
本文观察了10名游泳运动员和10名实验室工作人员在递增负荷运动中心功能的变化及其与无氧阈的关系.结果为:(1)游泳队员的无氧阈值明显高于无训练的实验室工作人员;(2)运动中每搏量稳定时的强度与无氧阈强度是密切相关的;(3)运动至无氧阈强度以后,心输出量的增加主要靠心率的增加来维持;(4)无训练者在运动一开始就动用心力储备,增加心率和每搏量,而游泳队员则在运动至40W以后才开始增加心率和每搏量.这些结果表明,无氧阈与心功能具有很密切的关系,可用它来反映心功能的好坏. 相似文献
998.
Dr. Shosaku Nakahara M.D. Hideaki Itoh M.D. Ryuichi Mibu M.D. Shinichi Ikeda M.D. Yoshihiro Oohata M.D. Kamesaburo Kitano M.D. Yoshihiko Nakamura M.D. 《Diseases of the colon and rectum》1988,31(10):762-766
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line,
using an EEA™ stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following
surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients
could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure
and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct
tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily
by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation
is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is
a functionally acceptable option for low rectal cancer. 相似文献
999.
1000.
Aichi Ogasawara Takahiro Hirano Hiroaki Hisa Susumu Satoh 《Clinical and experimental pharmacology & physiology》1995,22(4):311-313
1. Intrarenal arterial infusion of hypertonic saline (HS) transiently increased and then gradually reduced renal blood flow (RBF) in anaesthetized dogs. Glomerular filtration rate (GFR) but not filtration fraction decreased at the end of the infusion. 2. In the presence of a potassium channel opener cromakalim (0.3 μg/kg per min), HS infusion failed to reduce RBF; the initial increase in RBF was maintained throughout the infusion. Since cromakalim also prevented the decrease in GFR, HS infusion lowered filtration fraction. 3. The results suggest that cromakalim inhibits both pre-and postglomerular vasoconstriction induced by HS infusion. 相似文献