全文获取类型
收费全文 | 264242篇 |
免费 | 24560篇 |
国内免费 | 20598篇 |
专业分类
耳鼻咽喉 | 2015篇 |
儿科学 | 2312篇 |
妇产科学 | 3023篇 |
基础医学 | 32672篇 |
口腔科学 | 4294篇 |
临床医学 | 37976篇 |
内科学 | 38600篇 |
皮肤病学 | 2411篇 |
神经病学 | 14898篇 |
特种医学 | 9568篇 |
外国民族医学 | 198篇 |
外科学 | 25159篇 |
综合类 | 44139篇 |
现状与发展 | 74篇 |
一般理论 | 27篇 |
预防医学 | 15978篇 |
眼科学 | 8182篇 |
药学 | 28281篇 |
300篇 | |
中国医学 | 15674篇 |
肿瘤学 | 23619篇 |
出版年
2024年 | 946篇 |
2023年 | 4401篇 |
2022年 | 11409篇 |
2021年 | 14126篇 |
2020年 | 10699篇 |
2019年 | 9328篇 |
2018年 | 9692篇 |
2017年 | 8527篇 |
2016年 | 8116篇 |
2015年 | 12218篇 |
2014年 | 14991篇 |
2013年 | 12568篇 |
2012年 | 18785篇 |
2011年 | 21590篇 |
2010年 | 13053篇 |
2009年 | 10078篇 |
2008年 | 13378篇 |
2007年 | 13402篇 |
2006年 | 13634篇 |
2005年 | 13890篇 |
2004年 | 8234篇 |
2003年 | 7646篇 |
2002年 | 6411篇 |
2001年 | 5701篇 |
2000年 | 6422篇 |
1999年 | 7181篇 |
1998年 | 4741篇 |
1997年 | 4752篇 |
1996年 | 3678篇 |
1995年 | 3514篇 |
1994年 | 2900篇 |
1993年 | 1965篇 |
1992年 | 2214篇 |
1991年 | 1843篇 |
1990年 | 1569篇 |
1989年 | 1333篇 |
1988年 | 1135篇 |
1987年 | 990篇 |
1986年 | 749篇 |
1985年 | 611篇 |
1984年 | 349篇 |
1983年 | 215篇 |
1982年 | 115篇 |
1981年 | 127篇 |
1980年 | 82篇 |
1979年 | 90篇 |
1965年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 13 毫秒
51.
冠心病是一种常见的心身疾病,是由于动脉硬化、狭窄、阻塞,引起心肌缺血、缺氧甚至坏死,而导致心绞痛、心律失常、心肌梗死、心力衰竭或心脏骤停[1]。目前,冠心病的发病率在40岁以上的人群中占4%~7%,且呈不断上升趋势,这引起了世界卫生组织(WHO)和各国的广泛关注[2]。因此,对冠心病病人开展有关心理行为、生活方式等方面的健康教育和护理干预非常重要。通过接受教育,病人对自身的问题有明确认识,能利用所学知识进行自我保健,有利于提高病人的生活质量,他们了解和掌握了相关知识,并能在实际生活中得到应用。现将护理干预对冠心病病人的效果… 相似文献
52.
53.
A case of hemianaesthesia caused by right hemisphere stroke was found to have good sensitivity and cutaneous localisation when she touched her impaired hand with her good contralateral hand or with a probe held by that hand. The capacity did not depend solely upon movement or positioning of her right arm, and she could also discriminate whether her own left fingers, as opposed to someone else's inter-digitated fingers, were being touched, but only when she did the touching. Thus, the threshold of the impaired hand appeared to be markedly affected by active involvement of the contralateral limb in delivering the stimulus. 相似文献
54.
Zhipan Zhang Gaoquan Shi 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2004,569(2):197-202
Poly (3-phenylthiophene) (P3PhT) films have been electrochemically synthesized by direct oxidation of 3-phenylthiophene in the electrolyte of pure boron trifluoride diethyl etherate (BFEE). The oxidation potential of the monomer was measured to be 1.29 V (vs. SCE), and about 0.15 V lower than that measured in a neutral medium of acetonitrile. Free-standing P3PhT film with tensile strength of 32–40 MPa has been obtained for the first time. The morphology and the structure of the polymer film have been studied by scanning electron microscopy, infrared and Raman spectroscopies. Raman spectral results demonstrated that the doping level of the P3PhT film increased with film thickness during electrochemical growth process. 相似文献
55.
Amidou S Traoré Marie-France Guidoin Yves Marois Ze Zhang Yvan Douville Robert Guidoin Martin W King André-Pierre Legrand 《Journal of investigative surgery》2007,20(2):121-133
Magnetic resonance imaging (MRI) and magnetic resonance (MR) relaxometry were used to assess noninvasively the tissue response of a new uncoated hybrid braided suture made from a combination of ultra-high-molecular-weight polyethylene (UHMWPE) and polyester (polyethylene terephthalate) (PET) yarns in comparison to a silicone impregnated braided 100% polyester (PET) control suture (Ticron). Both biomaterials were monitored for a period of 30 days following implantation in both incised and nonincised paravertebral rabbit muscles. In all cases, MR images and relaxometry demonstrated that the hybrid suture elicited either a milder or a similar tissue and cellular response compared to the control suture. These findings were confirmed by conventional histological analysis of the surrounding tissues. They also demonstrated that the hybrid suture promoted faster healing in terms of collagen infiltration between the yarns and individual filaments. This milder inflammatory reaction and improved biocompatibility represent a real advantage in the healing performance of sutures for cardiac and vascular surgery, and support the need for continued research and development of hybrid structures. This study also demonstrated the ability of MRI techniques to noninvasively evaluate the biocompatibility of biomaterials. By extending the capacity of MR diagnostic tools from patients to experimental animals, it is now possible to validate the healing performance of foreign materials with statistical reliability and fewer animals. 相似文献
56.
Late-onset and Recurrent Neonatal Group B Streptococcal Disease Associated with Breast-milk Transmission 总被引:2,自引:0,他引:2
Michael Kotiw Gwang W. Zhang Grant Daggard Elizabeth Reiss-Levy John W. Tapsall Andrew Numa 《Pediatric and developmental pathology》2003,6(3):251-256
The purpose of the study was to determine the epidemiological relationships in three unrelated cases of neonatal late-onset Group B streptococcal (GBS) disease and maternal breast-milk infection with GBS. All deliveries were by cesarean section; case 1 was at term, and cases 2 and 3 were at 32- and 33-wk gestation, respectively. Case 1 relates to a mother with clinical mastitis and recurrent GBS infection in a 20-day-old male infant. Following antibiotic therapy and cessation of breast-feeding, the infant recovered without sequelae. Case 2 refers to a mother with clinical mastitis and the occurrence of late-onset GBS disease in 5-wk-old male twins. Despite intervention, one infant died and the second became ill. Following antibiotic therapy and cessation of breast-feeding, the surviving infant recovered without sequelae. Case 3 refers to a mother with sub-clinical mastitis and late-onset GBS infection occurring in a 6-day-old female twin. Following intervention, the infant recovered but suffered a bilateral thalamic infarction resulting in developmental delay and a severe seizure disorder. Following recovery of GBS from an inapparent mastitis and cessation of breast-feeding, the second infant remained well. Blood cultures from all affected infants and maternal breast milk were positive for GBS. Epidemiological relationships between neonatal- and maternal-derived GBS isolates were confirmed by a random amplified polymorphic DNA polymerase chain reaction assay (RAPD-PCR). This study is significant in that it has demonstrated that maternal milk (in cases of either clinical or sub-clinical mastitis) can be a potential source of infection resulting in either late-onset or recurrent neonatal GBS disease. 相似文献
57.
58.
Min Zhang Wen-Bin Li Jin-Xia Geng Qing-Jun Li Xiao-Cai Sun Xiao-Hui Xian Jie Qi Shu-Qin Li 《Journal of cerebral blood flow and metabolism》2007,27(7):1352-1368
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP. 相似文献
59.
60.
Z-Y Sun J Wei L Xie Y Shen S-Z Liu G-Z Ju J-P Shi Y-Q Yu X Zhang Q Xu G P Hemmings 《European psychiatry》2004,19(6):354-357
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3'-untranslated region of the CLDN5 locus was associated with schizophrenia (chi(2) = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5'-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (chi(2)) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (chi(2) = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors. 相似文献