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51.
目的:利用一种改进的三箱社交装置评价动物的社交偏好程度,并探索该方法的可行性。方法:采用注意力缺陷多动障碍(ADHD)大鼠作为社交障碍模型动物,以同源大鼠(WKY)大鼠和Wistar大鼠作为对照组,模型组采用治疗ADHD的临床常用中成药小儿黄龙颗粒(1.88 g/kg、3.75 g/kg)灌胃给药16 d。利用改进的三箱社交箱,以待测鼠在陌生鼠侧密切交流区的时间、频次、路程及相关比例作为行为学指标,检测该方法对社交行为评价的可行性。结果:与Wistar大鼠组比较,模型组大鼠与WKY组大鼠在密切交流区域及有陌生鼠侧区域的时间显著减少(P<0.01),其他指标如频次、路程及比例也均有不同程度减少,小儿黄龙颗粒两剂量均能增加模型大鼠上述各指标数值。结论:该方法能准确捕捉动物的社交行为特征,实现对动物社交偏好程度的全面、客观评价。  相似文献   
52.
目的:为了进一步了解间歇性气囊挤压法(Intermittent pneumatic compression, IPC)挤压大鼠腿部与一氧化氮(NO)的关系.方法:检测了大鼠骨骼肌中3种一氧化氮合酶(NOS)同工酶:神经型NOS(nNOS);诱导型NOS(iNOS)和内皮细胞型NOS(eNOS)mRNA在IPC作用后的表达变化.25只SD大鼠被随机分为3个模拟实验组和4个IPC实验组.每只鼠取右侧胫前肌(AT)和提睾肌(CM)作为正常对照.IPC组挤压0.5,1,和5h,及挤压5h加等待4h,模拟实验组除不挤压外,其他操作均与实验组相同,然后分离左侧AT和CM作为处理后样品.所有样品应用RT-PCR进行NOS mRNA测定.以样品中看家基因2,3-二羟基丙醛-3-磷酸脱氢酶(GAPHD)cDNA为内参,与NOS cDNA 共同扩增.PCR产物电泳条带密度用NIH图像分析软件定量,并以与正常对照的对比值作为变化比率.结果:在IPC作用0.5、1和5h后,eNOS mRNA显著上升,在AT中分别达到正常对照的1.2,1.8和2.6倍;在CM中分别达到1.2,1.8和2.7倍,而其他NOS,除5hIPC组的nNOS外,总体表现下调.在IPC作用1h加等待4h组中,eNOS mRNA回复至正常对照水平.结论:该结果证实了IPC产生的机械压力至少部分增加了血管壁的剪切压,使内皮细胞增加了NO产物的释放量,导致了挤压部位及远端肌肉的血管扩张和改善了微循环.  相似文献   
53.
Summary Some treatments used for Parkinson's disease attenuate locomotor depression in rats treated with reserpine and -methyl-p-tyrosine. In the present study memantine (2.5, 5.0mg/kg), amantadine (10, 20mg/kg) (both uncompetitive NMDA antagonists), and L-deprenyl (1.0, 5.0 mg/kg; MAO-B inhibitor) were tested for possible synergistic interactions with the dopamine agonists: bromocriptine (2.5, 5.0mg/kg) and L-DOPA (50, 100mg/kg, + benserazide, 100 mg/kg). At higher doses, memantine (10 mg/kg), amantadine (40 mg/kg), bromocriptine (5 and 10mg/kg) and L-DOPA (100, 200mg/kg) but not L-deprenyl (up to 10 mg/kg) produced a pronounced increase in locomotor activity when given alone. The combination of memantine, amantadine and L-deprenyl with bromocriptine did not result in synergism of action and, at best, an additive effect was seen. On the other hand the combination of these agents with L-DOPA produced a pronounced synergistic effect. Hence, the clinical observation that coadministration of L-DOPA with either memantine or amantadine results in enhancement of their action is also reflected in an animal model of Parkinson's disease. Such a combination therapy should allow the use of lower doses of both drugs which may reduce the occurrence of side effects and may also be predicted to have additional benefits related to the neuroprotective properties of memantine, amantadine, and L-deprenyl.  相似文献   
54.
本文报告了0.1%敌鼠钠盐配制成的不同毒饵在旅客列车上对急性灭鼠毒饵拒食残存鼠的杀灭试验效果。采用间隔投饵饱和投药法,投毒14天便有效地杀灭了旅客列车上对急性灭鼠毒饵拒食残存鼠,粉迹法考核灭效达100%。敌鼠钠盐配制的毒饵适口性好,灭效高,现阶段列车灭鼠中,仍有较好的应用价值。  相似文献   
55.
应用 D M B A 诱发的雌性 S D 大鼠乳腺癌模型,初步探讨了大鼠乳腺受致癌剂作用后,三苯氧胺对乳腺癌发生的影响。结果显示:三苯氧胺使恶性肿瘤出现的平均潜伏期明显延长,恶性肿瘤的发生率明显降低。  相似文献   
56.
Aim: To find out the toxic effect of endosulfan on the tesficular function of pubertal rats, Methods: Male rats of pu-bertal age were orally administered endosulfan at a dose of 1.0 mg/kg body weight for 30 days. Twenty-four hours af-ter the last tmagnent, the rats were sacrificed and the testis, epididymis, seminal vesicles and ventral prostate were re-moved and weighed. A 10 % testicular homogenate was prepared for biochemical estimations. Results: In endosul-fan-treated rats, there were a reduction in the body weight and the weights of testis and accessory sex organs, a de-crease in the testicular lactate and pyruvate activities, and in the testicular DNA and RNA concentrations, whereas thetesticular protein concentration was slightly increased; the specific activity of testicular steroidogenic enzyme, 33OH-steroid dehydrogenase and the ascorbic acid level were decreased, which were correlated with a decrease in steroidoge-nesis. The lysosomal enzyme acid phosphatase and brush-border enzyme alkaline phosphatase activities were also de-creased in the testis of treated rats. Conclusion: In puhertal rats, endosulfan treaanent inhibits the testicular functions.(Asian J Androl 1999 Dec; 1 : 203 - 206)  相似文献   
57.
研究指出,吗啡可以抑制大鼠对伤害性刺激逃避性条件反射,吗啡抑制这一逃避性条件反射的作用部位在海马,吗啡的这一作用并不能完全被纳络酮所阻断  相似文献   
58.
Summary We found that a receptor ligands differentially regulated the acetylcholine (ACh) neurotransmission in the rat brain. Acute administration of (+)-N-allylnormetazocine [(+)-SKF-10,047], a prototype 1 receptor ligand, and 1,3-di(2-tolyl)guanidine (DTG), a non-specific receptor ligand, increased the extracellular ACh level in the rat hippocampus. This increase of hippocampal extracellular ACh level elicited by (+)-SKF-10,047 was more potent than that elicited by DTG. On the other hand, the striatal extracellular ACh level was slightly affected by (+)-SKF-10,047. In addition, DTG did not affect the striatal extracellular ACh level. Our previous studies have shown that both (+)-SKF-10,047 and DTG increased the extracellular ACh level in the rat frontal cortex. Taking all these data into consideration, the regulation of ACh neurotransmission by receptor ligands are different depending upon the brain region.  相似文献   
59.
Summary The binding of3H-WB 4101, an 1-adrenoceptor antagonist, to membranes of the cerebral cortex, the hypothalamus, and the lower brainstem was examined in adult spontaneously hypertensive (SH) rats and in normotensive Wistar Kyoto (WK) controls. The specific binding of3H-WB 4101 (0.33 nM) was significantly higher in homogenates from the cerebral cortex of SH rats as compared to WK rats. No differences were detected between SH and WK rats in the specific binding of3H-spiroperidol (0.25 nM), a dopamine receptor antagonist, to membranes from the corpus striatum and the limbic forebrain. The locomotor activity was significantly higher in SH rats as compared to WK controls, in all probability due to a lack of habituation to environmental change. It is suggested that the high reactivity of SH rats is related to a dysfunction in the noradrenergic neurons in the central nervous system.  相似文献   
60.
After bolus intravenous dosing of d-tubocurarine (d-TC) to rats, the twitch heights of the tibialis anterior muscle indirectly stimulated were followed, and its decrease was defined as pharmacologic response of d-TC. The relation between dose and response intensity was found to be well described with Hill's equation. According to a theory proposed by Smolen, Hill's equation was also applicable to the biophase d-TC concentration-response relation; the time courses of the relative biophase d-TC concentration indicated linear kinetics with dose levels 0.15 mg/kg and the occurrence of dose-dependent disposition with 0.30 mg/kg. After bolus i.v. dosing of3H-d-TC, plasma d-TC concentration obeyed a dose-independent two compartment model with doses 0.15mg/kg, but not with 0.30 mg/kg. This finding matched the above estimated with pharmacologic data. The active metabolite was not found in plasma and urine. The extent of d-TC plasma protein binding was independent of the wide range of plasma levels and its mean (±SD) value was 30.5 (±3.8). Plasma d-TC levels and pharmacologie response intensity were well correlated by Hill's equation and a three compartment model (the general two and the biophase compartments) in the dose range 0.15 mg/kg.This work was presented at the First Japanese-American Symposium on Pharmacokinetics and Biopharmaceutics, Tokyo, July 1981, which was held in memory of Dr. Sidney Riegelman.  相似文献   
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