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31.
Summary In a controlled crossover study, identical surgical procedures, the prophylactic removal of bilateral non-erupted 3rd molar teeth, were performed on two separate occasions in 24 healthy patients. Prior to each procedure, either betamethasone 9 mg (Celeston Chronodose®) or placebo was administered intramuscularly, in a randomized fashion. Objective and subjective assessments were recorded for paired comparison of the post-operative course, including swelling, pain, trismus, local temperature, bleeding, wound-healing and preference for treatment. In 23 patients, less swelling occurred when betamethasone was given pre-operatively. The mean reduction on the 3rd and 6th post-operative days was 55% (p<0.001) and 69% (p<0.001), respectively. Pain assessments (visual analogue scale) were significantly lower after the corticosteroid injection; mean response: 1st evening 17 vs 56 mm, 2nd evening 5 vs 37 mm, and 3rd evening 2 vs 13 mm. No significant correlation between the steroid-induced reduction in swelling and pain could be made. This may indicate that dissociation may exist between pain and other inflammatory events like swelling. No clinically apparent infection or other disturbance of wound-healing was noted after corticosteroid administration. This treatment course was preferred by 23 of the 24 patients.  相似文献   
32.
Summary Free cholesterol in lipids from the scalp and hair is predominantly a constituent of epidermal lipids. Therefore, a reduction in cholesterol content induced by a drug indicates a reduction in cell turnover in the epidermis. As, according to the literature, increased cell turnover in the epidermis results in formation of dandruff, a reduction in the proportion of cholesterol should indicate inhibition of the formation of dandruff. Conversely, an increase in free cholesterol should generally indicate a keratolytic effect. So unequivocal an interpretation has not so far been possible in persons with dandruff, as it was not known whether free cholesterol was increased or decreased. In addition, this interpretation was not possible after use of antimicrobial substances, as in vitro investigations had failed to exclude microbial esterification of cholesterol on the scalp. The present investigation has shown that correlation of free cholesterol level with cell turnover is permissible in patients with dandruff, even if antimicrobial drugs are being tested.  相似文献   
33.
Quipazine, a serotonin receptor stimulant, inhibited the response of rats to painful stimuli in two methods currently used to measure antinociception in these animals: the hot plate and tail compression test. The antinociceptive action was observed with doses ranging from 5 to 20 mg/kg i.p. according to the test situation.The effect was significantly antagonized by a pretreatment with methergoline, a potent serotonin antagonist. An electrolytic lesion placed in the nucleus raphe medianus, which produced a marked decrease of serotonin in the forebrain did not, or only slightly, affected the effect of quipazine, depending on the method used to measure antinociception.It is suggested that quipazine can produce antinociceptive action in rats by interacting with a serotonergic mechanism. The action appears to be due mainly to a direct action on postsynaptic serotonin receptors, although a presynaptic component can also contribute to the effect of quipazine.Visiting scientist from Clinica Neurologica, UniversitàVisiting scientist from Clinica Neurologica, Università  相似文献   
34.
Previous results suggest that norepinephrine decreases growth hormone (GH) release in goldfish by means of alpha-2 adrenoceptor activation. The intracellular mechanisms by which norepinephrine inhibits GH release were examined in the present study using dispersed goldfish pituitary cells. In 2-h static incubation experiments, norepinephrine and the alpha-2 agonist clonidine decreased basal GH release and the GH responses to stimulation by the dopamine D1 agonist SKF38393 and two native gonadotropin-releasing hormones (GnRH). Norepinephrine also reduced GH responses to the adenylate cyclase activator forskolin, two protein kinase C (PKC) activators (phorbol ester and synthetic diacylglycerol), and two Ca2+ ionophores (ionomycin and A23187). Similarly, norepinephrine applied as a 1-h pulse in cell column perifusion experiments reduced basal GH release and abolished the GH response to a 5-min pulse of arachidonic acid. In goldfish, D1-stimulated GH release is mediated by AC-, arachidonic acid-and Ca2+-dependent pathways, whereas GnRH action is coupled to PKC-and Ca2+-dependent mechanisms. These results suggest that norepinephrine activation of alpha-2 receptors inhibits ligand-induced GH secretion by actions subsequent to activation of these second messenger cascades. To further characterize norepinephrine mechanisms of action on unstimulated hormone release, the ability of norepinephrine and an alpha-2 agonist to affect activation of two second messenger cascades under basal conditions was also investigated. Static incubation with clonidine reduced cAMP production in a time-and dose-dependent manner, suggesting that norepinephrine inhibitory action can also be expressed at the level of cAMP production. Resting intracellular free calcium levels in single, identified goldfish somatotropes was unaffected by norepinephrine. However, the inhibitory effects of norepinephrine on basal GH secretion was not observed in the presence of a voltage-sensitive Ca2+ channel agonist. Whether these channels are targets for norepinephrine action on unstimulated GH release requires further investigation.  相似文献   
35.
硫色满酮3位Mannich碱衍生物的合成及其抗真菌活性   总被引:1,自引:1,他引:1  
目的 设计、合成硫色满酮3位Mannich碱类化合物,并对其抗真菌活性进行初步评价。方法 以对氟苯硫酚为原料,经多步反应合成目标化合物,并测定目标化合物的抗真菌活性。结果共合成了10个未见文献报道的新化合物,经红外光谱、核磁共振氟谱及元素分析确证了其结构。其中化合物3对大部分供试真菌活性强于或相当于对照品克霉唑。结论 硫色满目3位取代Mannich碱具有较强的抗真菌活性。  相似文献   
36.
目的 在体观察过氧化氢(H2O2)对豚鼠耳蜗功能及形态的影响。方法 实验动物分为4组,分别灌流人工外淋巴液(artificial perilymph,APL),50μMH2O2,100μMH2O2和200μMH2O2(H2O2均溶于APL中),并用Pl和H033342双染色方法观察H2O2引起的内耳细胞损伤情况。结果 所有H2O2灌流组复合动作电位((CAP)阈移和耳蜗微音电位(CM)幅度变化与人工外淋巴液组比较差异有显著性,且各H2O2组的变化呈现出浓度依赖性;Pl和H033342双染色方法发现外毛细胞是H2O2攻击的主要靶细胞,而Hensen细胞未见任何损伤痕迹。结论 H2O2可导致耳蜗功能下降及耳蜗毛细胞损伤:Hensen细胞较毛细胞可能具有更强的抗氧化能力。  相似文献   
37.
消瘀散消肿止痛作用的实验观察   总被引:2,自引:2,他引:2  
消瘀散在临床运用中有较好的消肿止痛之功效.为了证实其药理作用,作者用大白鼠建立急性软组织损伤和血肿的实验模型,使用消疾散进行治疗。观察结果表明该药能够有效抑制创伤性无菌性炎症反应,促进血肿吸收,提高实验动物的痛阈值;而且药效随作用时间的延长而逐渐增加。实验结果为该药的消肿止痛作用提供了科学依据。  相似文献   
38.
镫骨全切除和吸引噪声对豚鼠耳蜗功能与超微结构的影响   总被引:1,自引:0,他引:1  
本实验应用耳蜗电图和扫描、透射电镜等技术观察了6组(44只)豚鼠镫骨全切除后,前庭窗开放时间的长短和听泡内使用吸引器对耳蜗功能和超微结构的影响程度.结果如下:①随前庭窗开放时间的延长、复合蜗神经动作电位(compound action potential.CAP)反应阈进行性提高,开放180min可导致底回部分外毛细胞变性或破坏;②镫骨全切除后,听泡内较长时间地(60min)应用吸引器可引起CAP明显阈移和耳蜗底回部分外毛细胞的不可逆病变;③镫骨未切除时,听泡内吸引60min,仅引起CAP阈移,但外毛细胞未见损伤.结果提示:术中长时间开放前庭窗和鼓室内应用吸引器可能是引起镫骨全切除术后感音神经性聋的因素之一,但鼓室成形术中鼓室内吸引噪声可能因其强度不够大,不足以引起术后感音神经性聋.  相似文献   
39.
药用老鹳草原植物分布概述   总被引:1,自引:1,他引:1  
通过对药用老鹳草常用品种及其同属原植物地区分布的概述,总结了目前国内外对药用老鹳草研究的各品系,为今后规范中药材的使用,以及开发更多的代用品提供相关前期基础。  相似文献   
40.
目的 观察豚鼠暴露于稳态强噪声后听神经复合动作电位(CAP)及神经丝蛋白(NFP)的变化。方法 选用20只(40耳)Preyer反射正常的健康豚鼠,分为4组,噪声暴露后存活7天组(N-7d)、14天组(N-14d)和2个月组(N-2m)各5只,空白对照组(C)5只。噪声强度130dB(A)SPL,连续暴露5小时,于暴露前、暴露后3、7、14天、暴露后2个月分别测试CAP—N1波反应阈。免疫组化反应分别检测对照组、暴露后7、14天组、暴露后2个月组动物耳蜗内NFP的表达。结果稳态强噪声暴露后CAP—N1波反应阈明显增高,于暴露后7天基本稳定。暴露后7、14天NFP表达无明显变化,暴露后2月NFP表达显著减弱。结论 130dB(A)SPL稳态强噪声暴露5小时可以导致豚鼠CAP中重度永久性阈移,噪声损伤的早期NFP改变不明显,耳蜗NFP染色反应随着存活时间延长逐渐减弱,反映了损伤后神经纤维中骨架蛋白存在变性过程。  相似文献   
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