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11.
B A Baldwin 《Physiology & behavior》1976,16(1):59-66
Goats, which have been depleted of sodium by loss of parotid saliva from a parotid fistula, have been trained to press panels with their muzzles in order to obatin small volumes of 4% (0.5 M) sodium bicarbonate to drink. Normal goats display no appetite for 4% (0.5 M) bicarbonate solutions. Goats which were depleted of sodium were highly motivated to work for bicarbonate solutions without displaying a marked fall in plasma sodium levels. It was not possible to train sodium depleted goats to press the panels to obtain intracarotid injections of 3% (0.5 M) salt solutions. The continuous intracarotid injection of concentrated 23% (3.9 M) solutions of NaCl, which increased the level of Na+ ions in the cephalic circulation by 11 to 18 m-equiv./1., did not reduce the rate at which sodium depleted goats pressed the panel to obtain 4% (0.5 M) bicarbonate solutions to drink. It was not possible to train sodium depleted goats to press the panel switch in order to obtain intraruminal injections of 4% (0.5 M) bicarbonate solution. 相似文献
12.
丹参对缺血心肌的保护作用 总被引:8,自引:0,他引:8
目的:通过观察丹参注射液(DSZ)对缺血心肌细胞各项生化指标的影响,探讨其对心肌保护作用及其机制。方法:将小鼠随机分为四组,以40%丹参注射液0.25ml/10g灌胃处理,一周后腹腔注射垂体后叶素(Pit),复制心肌缺血模型,观察小鼠心肌组织一氧化氮合酶(NOS)及超氧化物岐化酶(SOD)活性、脂质过氧化物丙二醛(MDA)的含量、血清肌酸激酶(CK)活性。结果:DSZ预处理小鼠心肌组织NOS、SOD活性显著增加,而MDA的含量及血清CK活性显著降低(P<0.01)。结论:丹参减轻心肌缺血引发的损伤,保护心脏,其作用机制可能与增加缺血心肌组织NOS、SOD活性,减少MDA含量和血清CK活性有关。 相似文献
13.
J. Kievit H. G. J. M. Kuypers 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1977,29(3-4):299-322
Summary In 25 rhesus monkeys horseradish peroxidase was injected in different parts of the frontal cortex. The retrogradely labelled thalamic neurons formed longitudinal bands, some of which crossed the internal medullary lamina, and extended from one thalamic nucleus into another. On the basis of these findings the frontal cortex was subdivided into seven transverse cortical strips which receive afferents from seven longitudinal bands of thalamic neurons. The most rostral transverse strip receives afferents from the most medial thalamic band which is oriented vertically and extends through the most medial part of the MD into the medial pulvinar. Progressively more caudally located transverse strips receive afferents from progressively more laterally located thalamic bands which in part are situated in the VL and show an increasing tilt towards the horizontal. Moreover, those parts of the various bands which are situated along the dorsal and lateral margin of the thalamus project to the medial portions of the transverse cortical strips, i.e. along the medial margin of the frontal lobe, while the other parts situated ventromedially in the thalamus project to the lateral portions of these strips, i.e. along the lateral margin of the frontal lobe.These data provide an alternative view of the organization of the thalamus and suggest that this structure contains a matrix of longitudinal cell columns which in some cases extend across specific nuclear borders and may represent the basic thalamic building blocks in respect to the thalamo-cortical connexions. 相似文献
14.
青岛大学附属烟台毓璜顶医院生殖医学中心对1例反复体外受精/卵细胞质内单精子注射(IVF/ICSI)助孕后早期胚胎发育停滞的患者进行了全外显子基因检测,发现了一种新的TUBB8基因突变型(c.208C>T/p.Pro70Ser),并进一步探讨了TUBB8基因突变与早期胚胎发育停滞之间的联系,为反复种植失败的诊断与治疗提供更多可能性。 相似文献
15.
目的探讨复方丹参注射液对小儿急性肾小球肾炎(AGN)的疗效及其机制.方法用复方丹参注射液治疗AGN患儿30例(观察组),并与对照组进行比较.观测两组患儿水肿,高血压,血尿,蛋白尿的变化,检测其血清超氧化物歧化酶(SOD)活性和尿液丙二醛(MDA)含量.结果观察组患儿血清SOD活性显著增高(P<0.01),高血压,水肿的缓解时间明显短于对照组(分别为P<0.001和P<0.01).其蛋白尿的转阴率也明显高于对照组(P<0.05).结论复方丹参注射液治疗小儿急性肾小球肾炎效果良好,其机制与提高机体的抗氧自由基的能力有关. 相似文献
16.
目的:采用指纹图谱结合一测多评法(QAMS)评价中成药丹参片的质量。方法:以丹参酮ⅡA为参照物建立丹参片醌类成分的高效液相色谱法(HPLC)指纹图谱。同时,测定丹参酮ⅡA与隐丹参酮、丹参酮Ⅰ的相对校正因子,以QAMS测定丹参片中丹参酮Ⅱ_A、隐丹参酮、丹参酮Ⅰ的含量。结果:建立了丹参片HPLC指纹图谱,并指认了全部5个共有峰,12批丹参片的相似度均大于0.99;QAMS测定了丹参片中3个醌类成分的含量,样品间存在一定波动性。结论:指纹图谱与QAMS结合的质量控制模式准确可靠,可为全面合理评价丹参片的质量提供参考。 相似文献
17.
骨髓腔内输注复方丹参注射液治疗再生障碍性贫血的临床研究 总被引:6,自引:0,他引:6
目的 :观察骨髓腔内输注复方丹参对再生障碍性贫血 50例的疗效 .方法 :采用骨髓腔内输注复方丹参液并中医辨证的方法治疗再生障碍性贫血 ,并对其作用机制进行了探讨。结果 :治愈 2 4例 ,缓解 8例 ,明显进步 1 3例 ,无效 5例 ,总有效率 90 %。结论 :复方丹参注射液骨髓腔内输注与中医辨证结合治疗再障 ,能提高临床疗效 相似文献
18.
[目的 ]探讨氨甲喋呤单次肌肉注射治疗异位妊娠的效果及适应症 .[方法 ]对 2 1例异位妊娠患者单次肌肉注射氨甲喋呤 ,剂量为 5 0mg/m2 ,每周检测绒毛膜促性腺激素水平 .[结果 ]17例 (80 % )成功 ,4例失败 ,成功与否与首次检测时的血绒毛膜促性腺激素值高低有关 .[结论 ]肌肉注射氨甲喋呤是简便而有效的治疗早期异位妊娠的方法之一 ,但应严格掌握适应症 .适用于异位妊娠包块直径小于 5cm、无内出血、血绒毛膜促性激素低于 16 0 0 μg/L者 相似文献
19.
目的探讨注射用头孢噻肟钠含量测定更加简便快速的方法;方法根据其化学结构的特点,采用一阶导数光谱法测定其含量;结果测定含量准确可靠且重现性好,平均回收率为99.87%(n=5),RSD为0.67%;结论可用于头孢噻肟钠原料药中问体和注射用无茵粉末等含量测定。 相似文献
20.
Atropine and scopolamine, injected intraventricularly, abolished typical emotional behaviour with aggression and autonomic and motor phenomena, as well as with clonic-tonic convulsions of intraventricularly injected muscarine. On the other hand, adrenergic and dopaminergic blocking agents, antihistamines, 5-hydroxytryptamine antagonists, antiepileptic drugs, and 5-hydroxytryptamine, administered intraventricularly, failed to antagonize the gross behavioural effects of intraventricular muscarine. However, ganglionic and sometimes neuromuscular blocking agents, as well as catecholamines and histamine injected intraventricularly, antagonized the emotional behaviour with aggression and depressed the autonomic and motor phenomena of small doses of intraventricular muscarine. In addition, emotional behaviour with aggression and autonomic and motor phenomena evoked by high doses of intraventricular muscarine were resistant to these antagonists administered intraventricularly. From these experiments it is concluded that the sites activated by muscarine in the CNS producing aggressive behaviour have the following characteristics: in high doses muscarine acted on muscarinic cholinoceptive sites, while in small doses it activated the cholinoceptive sites having muscarinic and nicotinic characteristics. Finally, the ability of single intraventricular injections of muscarine to trigger and to maintain the long-lasting gross behavioural effects cannot be ascribed to a rapid detonator transmission, but rather to an action that differs from a conventional transmitter function. 相似文献