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11.
To clarify the role of vasoactive intestinal polypeptide (VIP) and somatostatin, somatropin-release inhibiting factor, (SRIF) neurons in the response to organisms to noise or whole-body vibration stress, VIP and SRIF-like immunoreactivity were determined in various regions of the rat brain following exposure for 90 min to noise (broad band, 102 dB) or whole-body vibration (20 Hz, 4.0 g). Both noise and whole-body vibration significantly increased VIP-like immunoreactivity in the amygdala. A significant reduction of VIP like immunoreactivity in the hippocampus was induced only by whole-body vibration. On the other hand SRIF-like immunoreactivity was decreased significantly in the hypothalamus and increased significantly in the amygdala by noise and whole-body vibration, respectively. The present findings would seem to indicate that the amygdalofugal VIP neural system is involved in regulating hypothalamic and pituitary hormone secretions in non-specific reactions to stress. Responses of hippocampal VIP and the amygdalofugal SRIF to whole-body vibration stress are assumed to be activated as specific reactions to the stress.  相似文献   
12.
Noradrenergic terminal excitability: effects of opioids   总被引:2,自引:0,他引:2  
The local infusion of morphine or D-Ala2, Met5-enkephalinamide into the frontal cortical terminal fields of noradrenergic neurons of the nucleus locus coeruleus resulted in a decrease in the excitability of the axon terminal regions to direct electrical stimulation. These effects were concentration dependent and could be blocked or partially reversed by the local infusion of naloxone. Some evidence was obtained for a differential antagonizing effect of naloxone upon the effects of morphine and D-Ala2, Met5-enkephalinamide. These results are discussed with respect to an effect of opioids on the polarization and/or ionic conductance of the terminal fields of locus coeruleus neurons, and to the possible regulation of neurotransmitter release by presynaptic opiate receptors.  相似文献   
13.
We evaluated the effect of 2-deoxy-d-glucose (2-DG) on gastric emptying of a non nutrient solution in conscious rats using a Phenol red method. Intravenous injection of 2-deoxy-d-glucose dose-dependently increased the rate of gastric emptying. This stimulatory action of 2-DG was abolished by subdiaphragmatic vagotomy. Intracisternal injection of thyrotropin-releasing hormone (TRH) antibody blocked intracisternal TRH and intravenous 2-DG-induced enhancement of gastric empyting but not the stimulation of gastric emptying induced by intracisternal pancreatic polypeptide. The TRH antibody injected intraperitoneally had no effect. These results suggest that endogenous TRH in the brain is involved in vagal-dependent stimulation of gastric emptying by 2-DG.  相似文献   
14.
In rats, rapid eye movement (REM) sleep can be elicited by microinjection of vasoactive intestinal polypeptide (VIP) into the oral pontine reticular nucleus (PnO). In the present study, we investigated whether this area could also be a REM-promoting target for a peptide closely related to VIP: the pituitary adenylyl cyclase-activating polypeptide (PACAP). When administered into the posterior part of the PnO, but not in nearby areas, of freely moving chronically implanted rats, PACAP-27 and PACAP-38 (0.3 and 3 pmol) induced a marked enhancement (60-85% over baseline) of REM sleep for 8 h that could be prevented by prior infusion of the antagonist PACAP-(6-27) (3 pmol) into the same site. Moreover, injections of PACAP into the centre of the posterior PnO resulted in REM sleep enhancement which could last for up to 11 consecutive days. Quantitative autoradiography using [125I]PACAP-27 revealed the presence in the PnO of specific binding sites with high affinity for PACAP-27 and PACAP-38 (IC50 = 2.4 and 3.2 nM, respectively), but very low affinity for VIP (IC50 > 1 microM). These data suggest that PACAP within the PnO may play a key role in REM sleep regulation, and provide evidence for long-term (several days) mechanisms involved in such a control. PAC1 receptors which have a much higher affinity for PACAP than for VIP might mediate this long-term action of PACAP on REM sleep.  相似文献   
15.
鹿茸口服液促进RNA和蛋白质合成作用的研究   总被引:1,自引:0,他引:1  
目的:研究鹿茸口服液对青年及老年小鼠RNA和蛋白质合成的作用。方法:观察口服鹿茸口服液对小鼠肝RNA和蛋白质含量及^3H-Uridine和^3H-Leucine掺入的影响。结果:鹿茸口服液可明显增加老年小鼠肝RNA和蛋白质含量及[^3H]Uridine和[^3H]Leucine掺入RNA和蛋白质,作用明显强于青年小鼠。结论:鹿茸口服液对老年小鼠RNA和蛋白质合成有明显促进作用。  相似文献   
16.
AIM OF THE STUDY: To elucidate the pharmacological activities of deer antler acupuncture and TGF61538;1 on the acute and chronic phases of rheumatoid arthritis diseases. MATERIALS AND METHODS: Polyarthritis rats were administered with TGF61538;1 and water extract of deer antler acupunture (DAA), prepared from the pilose antler of Cervus korean TEMMINCK var. mantchuricus Swinhoe. TGF61538; (0.1 to 2 61549;g/animal) and DAA (5-100 61549;g/kg animal) were initiated 1 day before an arthritogenic dose of streptococcal cell wall fragments to see the effects on the joint swelling and distortion during the acute phase and the chronic phase of the disease. Arthritic index suppression of rat arthritis model was examined by TGF61538; and DAA administrations. RESULTS: TGF61538;1 and DAA diminished the polyarthritis development in rats. TGF61538; and DAA eliminated the joint swelling and distortion observed during the acute phase and the chronic phase of the disease. The TGF61538; and DAA suppressed the arthritis progress when administration was begun after acute phase of arthritis. DISCUSSION: Consistent with the inhibition of inflammatory cell recruitment into the synovium, TGF61538;1 and DAA reversed the leukocytosis associated with the chronic phase of the arthritis, respectively.  相似文献   
17.
胰岛淀粉样多肽是2型糖尿病的重要致病原因之一.为了研究胰岛淀粉样多肽的生物学作用及其应用范围,本文拟通过文本挖掘技术来对胰岛淀粉样多肽生化用专业试剂和试剂盒检测的研究发展趋势进行探测.  相似文献   
18.
ConstructionofExpressingPlasmidsofRecombinantFNPolypeptideswithBifunctional-domainandtheCharacterizationoftheProductsExpresse...  相似文献   
19.
Background: The integrated central actions of hormones secreted from pancreatic islets, the gut and adipocytes regulate both energy homeostasis and body weight. Dysregulation in these neurohormonal pathways probably contributes to pathogenesis of obesity and type 2 diabetes. Objective: To examine hormone-based therapies targeting these interrelated pathways as potential treatments for obesity and diabetes. Methods: Preclinical and clinical data on therapies based on hormones secreted from the pancreas (glucagon, insulin, amylin and pancreatic polypeptide), gut (glucagon-like peptide-1, glucose dependent insulinotropic polypeptide, cholecystokinin and peptide YY) and adipose tissue (leptin and adiponectin) as potential treatments for diabetes and obesity are reviewed. Results/conclusions: In diabetes, hormone-based treatments have translated into new clinical platforms including insulin analogs, the GLP-1-like peptide receptor agonist exenatide and amylinomimetic pramlintide, which due to their complex interplay and the progressive nature of diabetes, can be utilized in different settings. Various peptide hormones and agonists/antagonists are currently under investigation as new approaches to treatment of obesity and diabetes.  相似文献   
20.
朱满意  韦正祥 《浙江医学》2017,39(7):562-564,569
目的探讨脾多肽对急性脑出血致全身炎症反应综合征(SIRS)患者的疗效及其可能机制。方法将86例急性脑出血伴SIRS患者按随机数字表法分为常规治疗组和脾多肽联合治疗组,每组43例。两组患者均给予常规治疗,脾多肽联合治疗组在常规治疗的基础上加用脾多肽注射液10ml/d静脉滴注10d。观察并比较两组患者治疗前及治疗第3、7、10天的体温、呼吸、心率、WBC、超敏C反应蛋白(hs-CRP)、TNF-α、IL-1水平的变化,以及多器官功能障碍综合征(MODS)的发生率。结果脾多肽联合治疗组体温、呼吸、心率、WBC较常规治疗组改善情况更为明显(P<0.05或0.01)。两组患者hs-CRP、TNF-α、IL-1水平在治疗第7天均较治疗前显著下降(P<0.05或0.01),脾多肽联合治疗组下降更为显著(P<0.05或0.01)。脾多肽联合治疗组MODS发生率较常规治疗组显著降低(P<0.05)。结论脾多肽注射液对急性脑出血致SIRS患者的症状具有明显的改善作用,可抑制炎性细胞因子的释放,能明显降低MODS的发生率。  相似文献   
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