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61.
Adults accompanying 64 children attending a hospital out-patient clinic were questioned about treatment and injections given for illnesses in the previous month. Half the children had received injections, almost all given by private doctors: we consider most of these injections to have been unnecessary. Three girls were paralysed by aggravation poliomyelitis after unnecessary injections. Adults approved of injections although they did not know what was injected.  相似文献   
62.
This study was designed to investigate the effect of morphine on formalin-induced nociceptive responses in streptozotocin (STZ) induced-diabetic mice, noninsulin-dependent genetically diabetic db/db mice and their respective controls (ddY and +/+). In nondiabetic (ddY and +/+) mice, morphine (1–10 mg/kg, PO) dose dependently attenuated the biphasic nociceptive responses induced by SC injection of formalin to the hindpaw, demonstrating equipotency on both the first and second phases. Para-chlorophenylalanine (800 mg/kg × 2, PO) and pindolol (1 mg/kg, IP) reduced the effect of morphine on the first phase, sulpiride (10 mg/kg, IP) abolished the effect on both phases, while ketanserin (1 mg/kg, IP) had no effect. In STZ (200 mg/kg, IP)-diabetic mice, morphine weakly attenuated the nociception in comparison to control ddY mice, whereas it had comparable effects in both the first and second phases of control +/+ mice and db/db mice. The serotonergic agonist, meta-chlorophenylpiperazine (0.32–3.2 mg/kg, PO), dose dependently attenuated the biphasic nociceptive responses to formalin in both phases of diabetic mice; however, FR64822, a dopaminergic compound (0.1–10 mg/kg, PO), had little effect. We speculate that activation of both dopaminergic (DA)- and serotonergic-mediated mechanisms are potentially responsible for the effect of morphine on the first phase, while the DA-mediated effect is involved in the second phase. The DA-mediated mechanism, but not the serotonin-mediated one, appears to be altered in both STZ-diabetic and db/db mice. These results suggest that the attenuated effects of morphine might be due to a dopaminergic dysfunction in STZ mice, and that there might be other mechanisms compensating for this attenuation of dopaminergic function in db/db mice.  相似文献   
63.
The distribution of serotoninergic fibers in the guinea pig cochlear nucleus was studied with serotonin immunohistochemistry. In addition, the origin of the serotoninergic fibers was determined by combining the retrograde transport of wheat germ agglutinin-apohorseradish peroxidase (gold conjugated) with serotonin immunohistochemistry. Immunoreactivity was present in varicose and nonvaricose fibers that were unevenly distributed throughout the cochlear nucleus. The fibers were most prominent in the superficial layers of the dorsal cochlear nucleus and the anterior spherical cell area of the anteroventral cochlear nucleus. Although less prominent, serotonin-positive fibers were also present in the remaining part of the anteroventral cochlear nucleus and the posteroventral cochlear nucleus. A few positive fibers were present in the auditory nerve root and the dorsal and intermediate acoustic stiae. Double-labeled cells were found throughout the rostral- caudal extent of the serotoninergic system from the caudal linear nucleus to the nucleus raphe pallidus. However, most were confined to the dorsal (52%) and median (18%) raphe nuclei. Some serotoninergic cell groups contained retrogradely labeled cells that were not serotonin immunoreactive, indicating nonauditory afferents to cochlear nucleus containing other neurotransmitter substances. Serotonin may tonically modulate auditory processing within the cochlear nucleus as well as influence certain ascending auditory pathways. Most of the serotonin in the cochlear nucleus comes from superior raphe nuclei that also project to basal ganglia motor systems and limbic strctures. Therefore, the effect of serotonin on the cochlear nucleus may be related to level of arousal or behavioral state. © 1995 Willy-Liss, Inc.  相似文献   
64.
为了观察糖皮质激素对哮喘患者白细胞介素(IL)-5mRNA表达与嗜酸性粒细胞激活作用的影响,本研究用逆转录(RT)-聚合酶链反应(PCR)法半定量分析了哮喘患者用糖皮质激素治疗前后外周血单个核细胞(PBMC)中IL-5mRNA表达水平的变化,检测了血清嗜酸细胞阳离子蛋白(ECP)浓度、一秒钟用力呼气容积(FEV1)下降20%时的乙酰甲胆碱(MCH)激发浓度(MCH-PC20值)和基础FEV1占用力肺活量比值(FEV1%)等指标。结果发现,糖皮质激素不仅能改善哮喘患者的气道高反应性和通气功能,而且还可抑制PBMC中IL-5mRNA的表达和降低血清ECP浓度(P<0.05);血清ECP浓度下降幅度或MCH-PC20值改善幅度与IL-5mRNA表达水平下降幅度之间均呈显著正相关(r分别为0.5426和0.4857,P值<0.05)。提示糖皮质激素可能是通过抑制IL-5基因的转录,从而抑制后者对嗜酸性粒细胞的活化,而发挥其抗气道炎症反应和降低气道高反应性的作用。  相似文献   
65.
It was shown previously that chronic exposure to opiate agonists increases adenylyl cyclase (AC) activity, a phenomenon termed AC superactivation (or supersensitization). More recently, we showed that acute Gi/o-coupled receptor activation inhibits the activity of several AC isozymes, including Ca2+/calmodulin-stimulated AC-I and -VIII, whereas chronic receptor activation induces their superactivation. Here, we report that both acute μ-opioid receptor-induced inhibition and chronic induced superactivation of AC-I and -VIII are pertussis toxin sensitive. In addition, we show that proteins that interfere with the activity of {ie195-2} subunits ({ie195-3} scavengers) strongly attenuate the acute inhibition of AC-I and -VIII and the superactivation of AC-I, and abolish the superactivation of AC-VIII. Based on these results, we suggest that {ie195-4} is involved in the acute inhibition and chronic agonist-induced superactivation of AC types I and VIII.  相似文献   
66.
The effect of verapamil on resting and depolarization-induced monoamine release was investigated in rat hippocampal synaptosomes prelabeled with [3H]-5-hydroxytryptamine (HT) or [3H]-norepinephrine (NE) and rat striatal synaptosomes prelabeled with [3H]-dopamine (DA). Verapamil (50 μM) completely abolishes high K+-induced [3H]-NE release, but paradoxically facilitates high K+-induced [3H]-5-HT and [3H]-DA release. All these high K+-evoked responses were Ca2+ dependent. Verapamil does not modify [3H]-NE baseline release, but increases dose dependently [3H]-5-HT and [3H]-DA baseline release. Verapamil (10 μM, for 5 min) increases endogenous DA release (70%) and endogenous 5-HT release (40%) independently on the presence of external Ca2+. The total amount of these monoamines (released plus retained by the preparation) and their metabolites (DOPAC and 5-HIAA) was similar in control and verapamil-treated synaptosomes. Verapamil displaces [3H]-spiroperidol specific binding (Ki of 2.4 × 10?6M) and [3H]-SCH-23390 specific binding (Ki of 9 × 10?6M) from striatal synaptosomal membranes, and [3H]-5-HT specific binding (Ki of 3 × 10?5M) from hippocampal synaptosomal membranes. It is concluded that in addition to the Ca2+ antagonistic properties of verapamil on the Ca2+-dependent, depolarization-induced release of some neurotransmitters [gamma aminobutyric acid (GABA and NE)], another mechanism probably mediated by presynaptic receptors underlies the effects of verapamil on DA and 5-HT release from discrete brain regions. © 1995 Wiley-Liss, Inc.  相似文献   
67.
丝裂霉素C与5—Fu用于抗青光眼滤过性手术的对比研究   总被引:1,自引:0,他引:1  
采用随机、双讯,前瞻对照的方法比较了丝裂霉素C(MMC)和5-氟尿嘧啶对难治性青光眼小梁切除手术的安全性和有效性。39例病人随机分成二组,一组使用MMC,另一组使用5-Fu。结果提示:(1)MMC组手术成功率高于5-Fu组;(2)MMC组角膜上皮缺损发生率,结膜创口渗漏率明显低于5-Fu组。  相似文献   
68.
Serotonin (5-HT) may be inhibitory to micturition at a spinal level. A potential mechanism of action for serotonergic inhibition of bladder function is a depression of the ascending limb of the supraspinal reflex mediating micturition. Ascending activity evoked by pelvic nerve stimulation was recorded in the thoracic spinal cord of anesthetized cats. For comparison, spinal reflex activity evoked by pelvic nerve stimulation was recorded on the pudendal nerve. The effects of intrathecal administration of serotonergic agents were examined to determine whether spinal and supraspinal responses to bladder afferent activation were modulated by 5-HT. Methysergide (60 nmol), a non-selective serotonergic antagonist, increased ascending activity by 61±7% and depressed spinal reflex activity by 38±6%. Zatosetron (10 nmol), a 5-HT3 antagonist had a similar effect on both activities (increased by 93±24% and decreased by 77±7%, respectively). The effect on ascending activity of blocking 5-HT3 receptors was also confirmed with ICS 205930 and MDL 72222. 2-Methyl-5-HT (800 nmol), a 5-HT3 agonist, depressed ascending activity to 46±9% of control, but enhanced spinal reflex activity by 73±92%. These results demonstrate that stimulation of 5-HT3 and methysergide-sensitive 5-HT receptors can inhibit ascending activity and facilitate spinal reflex activity elicited by activation of bladder afferents. It is suggested that descending serotonergic pathways may participate in the spinal coordination of urinary continence.  相似文献   
69.
Substance P (SP) is a tachykinin involved in the regulation of inflammatory processes. To investigate a modulatory role of the neuropeptide SP in allergic inflammation, we studied its priming effect on human eosinophil chemotaxis and kinetic responses towards platelet activating factor (PAF) and recombinant human interleukin 5 (rhlL-5). Blood was obtained from normal subjects and eosinophils were separated by Percoll discontinuous density gradient centrifugation. High purification was obtained by negative selection procedure (CD16-beads) and the experiments were performed in a 48-well microchemotaxis Boyden chamber. In the present study we demonstrate a potent synergistic effect of 100nM dose of SP on the migratory function of human eosinophils stimulated by PAF and rhIL-5. This synergism was chemotaxis specific and was abolished by NK-1 receptor antagonist (FK888). The results suggest that neurogenic stimuli may play a significant role in eosinophil infiltration via its priming effect on the cell.  相似文献   
70.
Summary A behavioural test involving potentiation of the effects of an acute injection of -phenylethylamine (10 mg kg–1 i.p.) was used to assess the time-course of type-B MAO inhibition after administration of (–)deprenyl (5 mg kg–1 i.p.) and of MD 240928 (20 mg kg–1 i.p.) respectively. Potentiation of the effects of -phenylethylamine was observed 1 h after injection of (–)deprenyl or MD 240928. This effect was still evident 120 h after administration of (–)deprenyl but not 24 h after administration of MD 240928. Comparisons of ex vivo estimates of MAO activity yielded a corresponding time-course for the recovery of this enzyme. The extent of MAO inhibition required for potentiation of the effects of -phenylethylamine was inferred from a comparison of the behavioural test results and the ex vivo MAO activity observed after (–)deprenyl administration. These comparisons indicate a significant underestimation of MD 240928-induced MAO inhibition using ex vivo measures. This underestimation is interpreted as evidence fordilution effects in the ex vivo assay of MAO inhibition. The potentiation of effects of -phenylethylamine under the present conditions is proposed as a useful and simple test for effects of reversible type-B MAO inhibitors.  相似文献   
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