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51.
The present study reports the distribution of Neuropeptide Y (NPY)-immunoreactive neurons and fibers in the forebrain of the adult carp Cyprinus carpio L.. Serial Nissl-stained sections were used for cytoarchitecture and identification of anatomical structures. Immunostaining of NPY-containing neurons and fibers was used as neurochemical marker and tool for comparison with other species, including the goldfish.The general outline of the cytoarchitecture of the carp forebrain is similar to that of other Cypriniformes. However, using NPY immunohistochemistry, we found several specific differences with the goldfish, especially in the diencephalon. In the hypothalamus of the carp NPY-immunoreactive (NPYir) neurons were identified in the n. dorsolateralis thalami, and in the n. ventralis lateralis thalami. In the same location, we observed the n. anterior hypothalami and the n. preglomerulosus pars lateralis, described in the goldfish, as parts of n. prerotundus. However, in the carp we were not able to identify a n. preglomerulosus pars medialis, a n. preglomerulosus pars medialis commissuralis and a n. glomerulosus. We describe a n. rotundus, in which we did not find substructures typical of the goldfish.Further differences with the goldfish, trout and salmon were also noted.  相似文献   
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选择急性心肌梗死(AMI)患者20例,心绞痛(AP)患者30例,并以30名正常人作对照,动态观察血浆神经肽Y(NPY)含量变化。结果显示:对照组NPY水平为92.50±11.33ng/L,AMI组发病第天为163±24.36ng/l,显著高于对照组(P〈0.001);第3天开始下降,第14天趋于正常(110.33±17.79ng/l)。AP组心绞痛发作期为168.52±29.86ng/L,显著高于  相似文献   
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运动训练对糖尿病大鼠糖代谢和下丘脑神经肽Y mRNA的影响   总被引:1,自引:0,他引:1  
目的:探讨运动训练对糖尿病大鼠糖代谢及其下丘脑神经肽Y(NPY)mRNA表达的影响。方法:30只SD大鼠随机分为对照组、糖尿病组(由链脲佐菌素诱导)和糖尿病 运动训练组(糖尿病大鼠进行无负重游泳运动,第1天游泳10min,以后每天递增10min,直到每天60min,每周5天,共10周)。10周后检测各组大鼠安静时血糖、血清胰岛素含量及下丘脑NPY mRNA表达。结果:与对照组相比,糖尿病组大鼠血糖显著升高,血清胰岛素水平显著降低;与糖尿病组相比,糖尿病 运动训练组大鼠血糖显著下降,血清胰岛素水平显著上升。糖尿病组大鼠下丘脑NPY mRNA表达显著高于对照组,糖尿病 运动训练组大鼠下丘脑NPY mRNA表达显著低于糖尿病组。结论:适宜的运动训练可能通过下调下丘脑NPY mRNA表达来改善糖尿病大鼠糖代谢异常。  相似文献   
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To clarify the dopaminergic regulation of neuropeptide Y (NPY) neurons, the effect of haloperidol on NPY in basal ganglia and the cerebral cortex of the rat brain was investigated by sensitive radioimmunoassay and immunocytochemistry using antiserum against rat NPY. After repeated intraperitoneal injections of haloperidol (5 mg/kg) for 6 days, the content of immunoreactive NPY was significantly decreased in the caudate-putamen, but significantly increased in the lateral prefrontal cortex. After treatment for 21 days, the content of immunoreactive NPY in the caudate-putamen remained significantly low, but the extent of change in the lateral prefrontal cortex diminished. In the medial prefrontal cortex, piriform cortex, parietal cortex and nucleus accumbens, no significant changes were found after treatment for either 6 or 21 days. These findings were compatible with those obtained by immunocytochemistry using the same antiserum: an increase of immunoreactive fibers and terminals in the lateral prefrontal cortex and their decrease in the caudate-putamen. However, in the nucleus accumbens the density of immunoreactive fibers and terminals was decreased in the rostral portion, but not in the caudal portion after haloperidol treatment for 6 and 21 days. These findings suggest that dopaminergic afferents region-specifically regulate dopamine-sensitive NPY neurons in the rat brain.  相似文献   
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目的 观察肾衰养真胶囊对慢性肾衰竭(CRF)营养不良大鼠下丘脑神经肽Y(NPY)mRNA及原阿片黑皮素(POMC)mRNA的表达及其营养状态的影响.方法 采用含0.5%腺嘌呤及4%酪蛋白饲料联合喂养的方法制作CRF营养不良大鼠模型,观察其营养不良发生时间,符合CRF营养不良模型的随机分为模型组、肾衰养真胶囊组和开同组.治疗4周后,检测下丘脑NPY mRNA和POMC mRNA表达水平.结果 肾衰养真胶囊组大鼠营养状况明显改善,下丘脑的NPY mRNA表达上调及POMC mRNA表达下调.结论 肾衰养真胶囊可改善CRF营养不良大鼠的营养状况,其机制可能是通过上调下丘脑NPY mRNA表达,下调下丘脑POMC mRNA表达,从而促进大鼠摄食.  相似文献   
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Changes of catecholamine and neuropeptide Y(NPY) were investigated in experimental acute renal failure (ARF) of rats. Concentrations of noradrenaline (NA) and dopamine (DA) were determined by chromatographic analysis using electrochemical detection. Renal content of NPY, identified by radioimmunoassay, was expressed as NPY-like immunoreactivity (NPY-LI). All animals with a plasma urea value higher than 200 mg/dl induced by injection of glycerol were employed as ARF subjects for the experiment. Formation of ARF was also confirmed by histological findings showing diffused necrosis of tubular epithelia. In ARF rats, renal contents of NA and DA decreased markedly (P<0.001), NA (ng/g wet tissue) decreased from 186.3±19.6 to 2.81±0.67 (n=8), and DA (ng/g wet tissue) decreased from 14.69±4.97 to 4.05±2.66 (n=8). Similarly, NPY-LI (pg/g wet tissue) in ARF was reduced significantly (P<0.001) from 435.23±35.82 to 4.61±0.52 (n=8). The decrease of NA in ARF was obtained parallel to the change of NPY-LI; degeneration of adrenergic nerve fibers was confirmed by immunohistochemical observation. Results obtained suggest damage to the adrenergic and the dopaminergic innervation in the kidneys during ARF.  相似文献   
60.
OBJECTIVE: In this experiment, we studied the chronic effects of NPY, as there were no data on long-term effects of NPY in vivo. METHODS: Complementary DNA encoding NPY was isolated, sequenced and cloned into the expression vector, pCEP4. The 6-23 clone 6 cell line was transfected with this clone. Two groups of 10 adult male WAG rats (180-250 g body weight) were injected with either untransfected 6-23 clone 6 or 6-23 clone 6 transfected with NPY cDNA [6-23 (NPY)]. After 8 weeks, the animals were killed, their plasma assayed for insulin. Pancreatic glucagon (PG), by RIA, and plasma glucose were measured. RESULTS: The transfected cells were shown to be producing fully processed, bioactive NPY. The expression of NPY was also confirmed by Northern blot analysis. The animals injected with 6-23 (NPY) cells gained significantly more weight than the controls, (on day 54, 31.89 +/- 3.56 vs. 24.1 +/- 4.12 g, n = 10, P < 0.05). Plasma insulin and PG increased significantly in NPY animals compared to controls. The total RNA extracted from tumours was analysed by Northern blotting and showed NPY mRNA expression in NPY animals, but not in controls. CONCLUSION: The long-term effects of NPY was confirmed by injection of the cells producing this peptide.  相似文献   
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