全文获取类型
收费全文 | 4714篇 |
免费 | 184篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 72篇 |
儿科学 | 62篇 |
妇产科学 | 51篇 |
基础医学 | 685篇 |
口腔科学 | 119篇 |
临床医学 | 289篇 |
内科学 | 1214篇 |
皮肤病学 | 64篇 |
神经病学 | 366篇 |
特种医学 | 177篇 |
外科学 | 630篇 |
综合类 | 23篇 |
预防医学 | 86篇 |
眼科学 | 216篇 |
药学 | 368篇 |
中国医学 | 9篇 |
肿瘤学 | 507篇 |
出版年
2023年 | 24篇 |
2022年 | 43篇 |
2021年 | 74篇 |
2020年 | 46篇 |
2019年 | 57篇 |
2018年 | 92篇 |
2017年 | 70篇 |
2016年 | 60篇 |
2015年 | 84篇 |
2014年 | 103篇 |
2013年 | 138篇 |
2012年 | 266篇 |
2011年 | 310篇 |
2010年 | 157篇 |
2009年 | 166篇 |
2008年 | 270篇 |
2007年 | 311篇 |
2006年 | 300篇 |
2005年 | 317篇 |
2004年 | 303篇 |
2003年 | 287篇 |
2002年 | 271篇 |
2001年 | 101篇 |
2000年 | 115篇 |
1999年 | 113篇 |
1998年 | 55篇 |
1997年 | 39篇 |
1996年 | 34篇 |
1995年 | 47篇 |
1994年 | 37篇 |
1993年 | 35篇 |
1992年 | 73篇 |
1991年 | 71篇 |
1990年 | 56篇 |
1989年 | 68篇 |
1988年 | 51篇 |
1987年 | 45篇 |
1986年 | 32篇 |
1985年 | 43篇 |
1984年 | 40篇 |
1983年 | 30篇 |
1982年 | 17篇 |
1981年 | 9篇 |
1980年 | 5篇 |
1979年 | 26篇 |
1978年 | 13篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1975年 | 5篇 |
1966年 | 5篇 |
排序方式: 共有4938条查询结果,搜索用时 15 毫秒
11.
Morito Nakayama MD Naoyuki Kataoka MD Yutaka Usui MD Naohiko Inase MD Shigemitsu Takayama MD Hirotaro Miura MD 《The Journal of emergency medicine》1992,10(6):729-734
When nasotracheal intubation with a fiberoptic bronchoscope is performed, the tube may be blocked in the nasal cavity or larynx, resulting in several complications including epistaxis and hoarseness. We review the causes and complications of tube blockage and discuss optimal techniques for minimizing it. 相似文献
12.
13.
Hikaru Matsuda Yoshiyuki Taenaka Nobukazu Ohkubo Masakatu Ohtani Kyouichi Nishigaki Shigeaki Ohtake Takuya Miura Nobuyuki Taenaka† Hisateru Takano Hajime Hirose Yasunaru Kawashima 《Artificial organs》1988,12(5):423-430
Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies. 相似文献
14.
Key words reversal of neuromuscular blockade pancuronium - neostigmine 相似文献
15.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
16.
This paper reports on how lymphatic vessels and their smooth muscle cells develop in the diaphragm of postnatal rats. Lymphatic endothelial cells in the diaphragm were labeled by an intraperitoneal injection of DiI-labeled acetylated low-density lipoprotein (DiIac-LDL). During postnatal week 1, DiI-ac-LDL was detected in many free cells in addition to distinct endothelial cells that formed lymphatic vessels. Occasionally, saccular lymphatics isolated from previously formed lymphatics were recognized; these were referred to as lymphatic islands. The DiI-ac-LDL-labeled free and lymphatic endothelial cells showed immunoreactivity for CD 34 and Flt-4, but most of them did not express either OX 62 or ED 1 immunoreactivity, with only some showing ED 1 immunoreactivity. This suggests that most of the DiI-ac-LDL-labeled elements were lymphatic endothelial cells, and that some were macrophages. After postnatal week 1, the DiI-ac-LDL positive cells were restricted to lymphatic vessels. Until postnatal week 6, lymphatic vessels increased as the diaphragm enlarged. Towards the end of postnatal week 2, free cells expressing alpha-smooth muscle actin (alpha-SMA) immunoreactivity increased in the diaphragm, and some of these were in contact with lymphatics. A coarse plexus of smooth muscle cells surrounding the lymphatic vessels first appeared at postnatal week 2, and this plexus became denser with age. Our findings indicate that lymphatic vessels are formed not only by sprouting from previously formed lymphatic vessels but also by migrating endothelial cells, and that smooth muscle cells may be differentiated from mesenchymal cells to form a plexus surrounding the lymphatic vessels. 相似文献
17.
18.
Quantitation of varicella-zoster virus DNA in patients with Ramsay Hunt syndrome and zoster sine herpete 总被引:3,自引:0,他引:3 下载免费PDF全文
Varicella-zoster virus (VZV) reactivation causes facial nerve palsy in Ramsay Hunt syndrome (RHS) and zoster sine herpete (ZSH) with and without zoster rash, respectively. In the present study, we analyzed the VZV DNA copy number in saliva samples from 25 patients with RHS and 31 patients with ZSH using a TaqMan PCR assay to determine differences in the viral load between the two diseases. VZV copy number in saliva peaked near the day of the appearance of zoster in patients with RHS. Consequently, VZV DNA was less frequently detected in patients with RHS who exhibited facial palsy several days after the appearance of zoster. These findings suggest that the VZV load in saliva samples reflects the kinetics of viral reactivation in patients with RHS. In addition, VZV DNA was equally detected in saliva from patients with RHS and ZSH, and there was no significant difference in the highest viral copy number between patients with RHS and those with ZSH. The VZV load does not appear to reflect a major difference between RHS and ZSH. 相似文献
19.
Poonkhum R Pisetpaisan K Wang BJ Anupunpisit V Ohtani Y Ohtani O 《Archives of histology and cytology》2003,66(4):317-326
The liver, which produces a large volume of lymph, has a lymphatic system which can be classified into three categories: portal, sublobular, and superficial lymphatic vessels. As little is known about the origin and pathways of sublobular lymph, this study demonstrates pathways of interstitial fluid flowing into sublobular lymphatic vessels. Livers from cats whose thoracic ducts were either ligated or non-ligated were examined by light-, transmission electron- and scanning electron-microscopy (SEM). Complete ligation of the thoracic duct caused significant dilation of the hepatic sinusoids, the space of Disse, and channels passing through the limiting plate. Sublobular interstitial space and sublobular lymphatic vessels were also expanded. The channels between hepatocytes forming the limiting plate contained collagen fibers, and connected the space of Disse with a sublobular interstitial space. The alkali-water maceration/SEM confirmed that collagen fibers traversing the layer of the limiting plate independently of blood vessels connected collagen fibers in the space of Disse with those in the sublobular space. Complete ligation of the thoracic duct also showed an accumulation of mast cells and plasma cells in the sublobular interstitial space. Our data suggest that fluid in the space of Disse flows along collagen fibers in channels traversing the limiting plate as well as those along the sinusoids and central veins that drain into sublobular veins, and enters the sublobular interstitial space to finally lead into sublobular lymphatic vessels. Our study has also shown that hepatic lymphostasis causes the accumulation of mast cells and plasma cells in the sublobular interstitial space, which may be involved in lymphangiogenesis and fibrogenesis. 相似文献
20.
Zhang H Yamamoto T Nanba E Kitamura Y Terada T Akaboshi S Yuasa I Ohtani K Nakamoto S Takeshita K Ohno K 《American journal of medical genetics》1999,82(5):368-370
A Japanese patient with tuberous sclerosis (TSC), who manifested with multiple lung cysts and pneumothorax, is described. All exons of two TSC genes, TSC1 and TSC2, in peripheral blood leukocytes from the patient were analyzed by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). A novel T-to-G transition was found in exon 19 of TSC2 at nucleotide position 2168. This mutation caused an amino acid change, L717R. There was no such mutation in any other family members or in 100 normal Japanese. An automated sequencer-assisted quantitative analysis of normal and mutated SSCP-bands revealed no loss of heterozygosity (LOH) in the lung cyst tissue of the patient. 相似文献