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91.
刘万忠  左阿玲 《药学学报》1992,27(4):294-298
报道一种新型结构的全固态乌头碱电化学检测器的研制及其在流动注射分析中的应用。采用流动注射分析法对川乌、草乌及其中成药(小活络丸)中剧毒成分(双酯型生物碱)进行了测试,方法简便快速,结果同光度法接近。本文还提出了电化学法研究乌头碱水解动力学原理。在pH 6.5,温度98℃的条件下测得乌头碱水解成苯甲酰乌头碱的速度常数为1.36×10-2min-1。  相似文献   
92.
标题 a)口服左旋-Sotatol治疗心肌梗死后左室功能不全患者生存研究(SWORD):试验依据、设计和方法   b)右旋-Sotatol对亚急性和陈旧性心肌梗死后左室功能不全患者病死率的影响研究作者 WaldoAL,CammAJ,deruyterH,等a)AmJCardiol,1995,75:1023~1027b)Lancet,1996,348:7~12  研究疾病:充血性心力衰竭。目的:右旋-Sotatol为一种具有专一性钾通道阻滞作用的抗心律失常药物。本研究将对其降低心肌梗死后左室功能不全…  相似文献   
93.
    
During atherogenesis, plaque macrophages take up and process deposited lipids, trigger inflammation, and form necrotic cores. The traditional inflammatory/anti-inflammatory paradigm has proven insufficient in explaining their complex disease-driving mechanisms. Instead, we now appreciate that macrophages exhibit remarkable heterogeneity and functional specialization in various pathological contexts, including atherosclerosis. Technical advances for studying individual cells, especially single-cell RNA sequencing, indeed allowed to identify novel macrophage subsets in both murine and human atherosclerosis, highlighting the existence of diverse macrophage activation states throughout pathogenesis. In addition, recent studies highlighted the role of the local microenvironment in shaping the macrophages’ phenotype and function. However, this remains largely undescribed in the context of atherosclerosis. In this review we explore the origins of macrophages and their functional specialization, shedding light on the diverse sources of macrophage accumulation in the atherosclerotic plaque. Next, we discuss the phenotypic diversity observed in both murine and human atherosclerosis, elucidating their distinct functions and spatial distribution within plaques. Finally, we highlight the importance of the local microenvironment in both phenotypic and functional specialization of macrophages in atherosclerosis and elaborate on the need for spatial multiomics approaches to provide a better understanding of the different macrophage subsets’ roles in the pathogenesis of atherosclerosis.  相似文献   
94.
95.
Riederer  SJ; Brody  WR; Enzmann  DR; Hall  AL; Maier  JK 《Radiology》1983,147(3):859-862
Temporal filtering methods were applied to iodine signal-to-noise ratio (SNR) restoration in intravenous hybrid subtraction digital subtraction angiography (DSA). For equal detected exposure rates hybrid subtraction had approximately 35% of the SNR of temporal subtraction. When matched filtering was applied to a DSA run, the filtered result had approximately two times higher SNR than the peak contrast image in the run. Thus, when matched filtering techniques were applied to the hybrid image sequence, the resultant SNR increased to about 70% of that of temporal subtraction. With an additional factor-of-two increase in exposure rate for the hybrid run, SNR parity with temporal subtraction could be achieved. This compared with a factor-of-nine increase in exposure that would be required if no filtering were performed. Experimental hybrid matched filter results, generated with intravenous canine DSA studies, supported the predictions in SNR performance.  相似文献   
96.
97.
Patients with the syndrome of chronic daily headache often report migrainous symptoms and consequently are diagnosed as having a primary headache syndrome. We report two cases of idiopathic intracranial hypertension causing chronic daily headache with migrainous features in the absence of associated papilledema.  相似文献   
98.
The effects of a chronic ethanol drinking schedule (20% solutionfor 6 weeks) on energy balance and carbohydrate and lipid metabolismhave been investigated in lean (32–36 g) and obesediabetic(40–44 g) CBA/Ca mice. The untreated obesediabetic miceexhibited hyperglycaemia, hypertriglyceridaemia, hyper-insulinaemiaand insulin resistance. The chronic ethanol treatment, whichyielded plasma ethanol levels of between 1 and 11 mM, loweredthe blood glucose, plasma insulin and tnacylglycerol levelstowards normal in the obese mice, but did not affect these parametersin the lean mice. The body weight of the obese mice tended toreturn to normal during the 6-week drinking period, althoughtheir total energy intake (9.2–10.0 kJ/g/week, food plusethanol-denved calories) was almost double that of the leanmice (4.8–5.4 kJ/g/week). The blood glucose response toacute insulin injection, which was significantly reduced inthe obese mice, became indistinguishable from the response ofnormal mice after chronic ethanol treatment. Soleus muscle glycogensynthesis in both lean and obese mice was not significantlyaltered by ethanol drinking, but brown adipose tissue lipogenesiswas significantly increased (by 50%) in the obese mice. It isproposed that ethanol is acting chronically to restore insulinsensitivity in the obese diabetic mice at doses which have littleor no effect in normal lean animals. This action is exerted,at least in part, at the level of brown adipose tissue lipogenesis.  相似文献   
99.
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
100.
Summary— To investigate the involvement of nitric oxyde (NO) derived from endothelial cells in the control of vascular tone in the rat mesenteric vascular bed, the effects of different procedures known to interfere with the NO-cyclic GMP pathway were evaluated both on the basal tone and on the vasodilatory responses to four muscarinic agonists. To this aim, rat isolated mesenteric vascular beds were perfused at constant pressure. Water infusion significantly increased the resting perfusion pressure whereas L-NOARG, L-NAME and methylene blue were devoid of effect. In noradrenaline-preconstricted vascular bed, the perfusion pressure was significantly increased after water or L-NAME infusion. The vasodilator response induced by subsequent addition of acetylcholine in bolus was not significantly modified by pre-treatment with indomethacin but was significantly reduced by water infusion. Reponses to acetylcholine and to three other muscarinic agonists -carbachol, oxotremorine or McNeil A 343- were assessed. Incubation with L-NAME did not modify the initial peak falls of the agonists except for Mc Neil A 343, whereas it significantly reduced the area under the pressure trace for all the substances. The latter effect was reversed after a subsequent incubation with L-Arginine. Finally, L-NAME strongly and significantly increased the drop in perfusion pressure and the area under the pressure trace following bolus of glyceryl trinitrate. These results suggest that in the mesenteric arterial bed of the rat, which can be considered as a resistant arteries preparation, basal tone appears to be controlled by a factor other than NO. Moreover, the vasodilator responses of muscarinic agonists are affected by L-NAME in their second late sustained phase only, which probably relies on a de novo synthesis of endothelium derived-NO. Finally, endothelium derived-NO exerts inhibitory effects both on the sensitivy of the vascular smooth muscle to glyceryl trinitrate and on the magnitude of its contraction in the presence of noradrenaline, two types of effects which are sensitive to L-NAME.  相似文献   
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