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921.
In order to develop a new technique for the measurement of local cerebral blood flow (CBF), the deuterium chemical shift imaging (2H-CSI) technique, an application of in vivo nuclear magnetic resonance (NMR), was used for the estimation of cerebral perfusion in rabbit infarction model. The 2H chemical shift images of rabbit brain were obtained every 30 seconds before and after intravenous injection of deuterated saline. The changes in 2H NMR signal intensity documented that the cerebral perfusion in the damaged area due to infarction decreased obviously compared to that in the intact area. These findings indicate that the 2H-CSI technique can be applied to the measurement of local CBF. The readily availability and limited toxicity of deuterated water may make possible to use this method in clinical cases.(Kito K, Arai T, Mori K, et al.: Deuterium chemical shift imaging for the estimation of cerebral perfusion in rabbit infarction model. J Anesth 7: 447–453, 1993)  相似文献   
922.
The present review summarizes recent studies describing the role of renal sympathetic innervation in the regulation of renal function during development. The afferent renal innervation appears early during fetal life and probably precedes the development of efferent renal nerves. There is suggestive evidence that renal nerves are required for the proper development of the kidney and that neurotrophic growth factors play an important role in renal embryogenesis and in renal tubular differentiation. Renal sympathetic innervation modulates renal hemodynamics early during development. Renal nerve stimulation during -adrenoceptor blockade produces renal vasodilation in fetal and newborn animals but not in adults. Unlike the effect of renal nerves on fetal renal hemodynamics which is observed in the young fetus, the role of renal sympathetic nerves in modulating fluid and electrolyte homeostasis seems to develop during late gestation. Recent studies have also shown that renal nerves play an important role in regulating renin secretion during the transition from fetal to newborn life. For example, renal denervation during fetal life suppressed the physiological rise in plasma renin activity associated with delivery and decreased renal renin mRNA levels after birth. Taken together, these studies suggest that renal nerves influence fetal renal development and that the influence of renal sympathetic innervation on renal hemodynamics and function changes with maturation.  相似文献   
923.
Sexual dysfunction is a well-known complication of chronic somatic illness. Eighty-six consecutive epileptic outpatients, 38 men and 48 women, without accompanying disorders, were studied. The frequency and symptoms of sexual dysfunction were compared with results from previous studies using identical sexological methodology. The previous studies were of diabetic patients and healthy controls. Eight percent of the epileptic men reported a sexual dysfunction compared to 44% of the diabetics and 13% of the controls. Epileptic women, diabetic women, and controls showed no significant differences in sexual dysfunction (29%, 28%, and 25%, respectively). In both sexes, the sexual function measured by frequencies of coitus and masturbation was normal. Most patients had good control of epileptic attacks on a treatment of monotherapy. Hormonal status was generally within normal limits in both men and women; only a few minor differences were found and they showed no correlation with sexual dysfunction. Psychologically and socially the patients did not differ appreciably from normals, and they exhibited a high degree of disease acceptance. This study, using a biopsychosocial approach in understanding sexual dysfunctions, is in contrast with previous, mainly uncontrolled, studies of epileptic patients that reported high frequencies of hyposexuality in males. We conclude that epilepsy does not necessarily increase the risk of sexual dysfunction in male or female.  相似文献   
924.
Cho  Moo J.  Adson  Anthony  Kezdy  F. J. 《Pharmaceutical research》1990,7(4):325-331
Transport of 14C-labeled acetic, propionic (PA), butyric, valeric, heptanoic (HA), and octanoic (OA) acids across the Madin Darby canine kidney (MDCK) epithelial cell monolayer grown on a porous polycarbonate membrane was studied in Hanks' balanced salt solution (HBSS) at 37°C in both apical-to-basolateral and basolateral-to-apical directions. At micromolar concentrations of solutes, metabolic decomposition was significant as evidenced by [14C]CO2 production during the OA transport. The apparent permeability (Pe) indicates that as lipophilicity increases, diffusion across the unstirred boundary layer becomes rate limiting. In support of this notion, transport of OA and HA was enhanced by agitation, showed an activation energy of 3.7 kcal/mol for OA, and resulted in identical Pe values for both transport directions. Analysis of Pe changes with varying alkyl chain length resulted in a G of –0.68 ± 0.09 kcal/mol for –CH2-group transfer from an aqueous phase to the MDCK cells. When the intercellular tight junctions were opened by the divalent chelator EGTA in Ca2+/Mg2+ -free HBSS, transport of the fluid-phase marker Lucifer yellow greatly increased because of paracellular leakage. PA transport also showed a significant increase, but OA transport was independent of EGTA. Although albumin also undergoes paracellular transport in the presence of EGTA and OA binds strongly to albumin, OA transport in EGTA solution was unchanged by albumin. These observations indicate that transmembrane transport is the major mechanism for lipophilic substances. The present study, together with earlier work on the transport of polar substances, shows that the MDCK cell monolayer is an excellent model of the transepithelial transport barrier.  相似文献   
925.
Objective To observe the level of muscarinic receptors in airway and lung tissues, and the effect of inhaled ipratropium bromide on these receptors in a rat model of chronic obstructive pulmonary disease (COPD). Methods This model was developed by exposure of rats to 250 ppm SO2 gas, 5?h/d, 5d/wk, for a period of 7 wk. The COPD rats inhaled 0.025% aerosolized iratropium bromide for 20 min, 2 times daily, in an airtight chamber. Muscarinic receptors in airway and lung tissues of normal rats, ipratropium bromide-treated COPD rats and the recovering COPD rats were measured by the radio-ligand binding assay. Results Airway/lung pathology and pulmonary function tests showed that chronic SO2 exposure caused pathophysiologic changes similar to those observed in human COPD. The density (0.038±0.011, pmol/mg protein) and affinity (Kd, 23±11 pmol/L) of muscarinic receptors in airway and lung tissues of COPD rats were not changed compared with those of normal control rats (0.030±0.008 and 29±19, respectively, P>0.05). Densities of the muscarinic receptors were not changed after inhalation of ipratropium bromide for 5 days, but increased significantly after inhalation for 30 days, as compared with those of the untreated COPD rats. The muscarinic receptors returned the normal levels at day 6 after cessation of ipratropium bromide treatment. There were no differences among different groups of rats in equilibrium dissociation constants (Kd). Conclusion A rat model of COPD with pathophysiologic changes similar to the human counterpart was developed using chronic SO2 exposure. There was no significant change in the number and function of muscarinic receptors in airway and lung tissues of the COPD rats, but upregulation of the muscarinic receptors was observed after long-term inhalation of ipratropium bromide.  相似文献   
926.
uPAR在人毛囊发育中的表达及其规律   总被引:1,自引:1,他引:0  
目的 探讨人胚胎毛囊形成发育过程中,尿激酶型纤溶酶原激活剂受体(uPAR)的表达及其规律。方法 用免疫细胞化学和原位杂交分别对人胚胎毛囊起始期、延长期、分化期和胎毛阶段的表皮及毛囊的uPAR蛋白及mRNA的表达进行了检测,用图像分析系统进行了定量测定。结果 uPAR在起始期和延长期的整个毛囊中有表达,在分化期和胎毛前期毛囊的外根鞘有表达。在起始期、延长期、分化期和胎毛阶段前期表皮的基底层、最外层细胞有阳性表达。阳性表达在延长期最高,呈现出先增后减的趋势。结论 uPAR与角质形成细胞的增殖和迁移密切相关。  相似文献   
927.
目的:针对开放微生物生长系统,探讨细菌波动生长的产生机制。方法:以单种群细菌为研究对象,应用非线性系统动力学和数值模拟分析方法讨论周围环境条件变化对细菌生长的影响关系。结果:建立了单种群细菌波动生长与环境关系数学模型。结论:证明了模型的合理性并给出了模型的数值模拟结果,为研究细菌波动生长规律作了量化分析探索。  相似文献   
928.
目的 研究丙型肝炎病毒(HCV)在体外培养原代人胎肝细胞和人肝癌细胞系7721中复制和表达的异同,探讨HCV体外培养条件。方法 原代人胎肝细胞系7721分别与HCV感染血清共孵育后,用逆转录-聚合酶链反应、原位杂交、免疫组化检测细胞和培养上清中的HCV RNA和抗原表达。结果 从孵育的2~3天,即可在细胞内和/或培养上清中间断地检出HCV RNA(其中HCV在7721细胞株中的复制至少可达66d,HCV在 人胎肝细胞中的复制持续25d);HCV抗原可在感染细胞内得到稳定表达,感染细胞内存在HCV负链RNA杂交信号,且多位于细胞浆。结论 两种肝细胞对HCV易感,尤其是7721细胞可以稳定地支持HCV体外复制,可用于HCV体外长期培养的靶细胞。  相似文献   
929.
从 1998年测得的 7~ 18岁壮族男女学生 5 2 49名 6项指标 (身高、坐高、体重、胸围、肩宽和骨盆宽 )的资料 ,计算出12项指数 ,并与汉族和蒙古族进行比较。结果显示 :12项指数中 ,年龄变化规律与汉族和蒙古族基本相似 ,但身体各部分的发育程度不同 ,并存在城乡差别。提示壮族学生体型为横径较宽的粗壮体型 ,城市男女生多数年龄组为长躯干型 ,乡村男女生多数年龄组为中躯干型 ;城乡男女生肩型大多为中肩型 ;全部年龄组的胸型均为窄胸型 ;城男 7~ 18岁、14岁以前乡男女及城女均为窄骨盆型 ,15岁以后的乡男女及城女为中骨盆型。  相似文献   
930.
生态药理与生物药理—论中药药性理论的本质   总被引:1,自引:1,他引:0  
目的:探讨中药药性理论的本质,方法:通过对医学人体理论,医学模式和药理理论内在关系的分析来剖析中药药性理论的本质,提出对中药药性理论本质的认识。结果:认为中药药性理论是传统中药药理理论,是适应中医学“生态-生物人体理论”的产物,中药药性理论是“生态药理”与“生物药理”相结合的产物即“生态-生物理”这是其本质所在,结论:传统中药药理即中药药性理论是“生态-生物药理”理论。  相似文献   
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