全文获取类型
收费全文 | 8648篇 |
免费 | 541篇 |
国内免费 | 68篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 177篇 |
妇产科学 | 87篇 |
基础医学 | 930篇 |
口腔科学 | 113篇 |
临床医学 | 972篇 |
内科学 | 2119篇 |
皮肤病学 | 156篇 |
神经病学 | 459篇 |
特种医学 | 220篇 |
外国民族医学 | 1篇 |
外科学 | 1659篇 |
综合类 | 222篇 |
现状与发展 | 1篇 |
一般理论 | 7篇 |
预防医学 | 527篇 |
眼科学 | 158篇 |
药学 | 802篇 |
中国医学 | 159篇 |
肿瘤学 | 446篇 |
出版年
2024年 | 16篇 |
2023年 | 178篇 |
2022年 | 542篇 |
2021年 | 674篇 |
2020年 | 404篇 |
2019年 | 480篇 |
2018年 | 473篇 |
2017年 | 296篇 |
2016年 | 317篇 |
2015年 | 357篇 |
2014年 | 416篇 |
2013年 | 496篇 |
2012年 | 757篇 |
2011年 | 690篇 |
2010年 | 339篇 |
2009年 | 309篇 |
2008年 | 465篇 |
2007年 | 433篇 |
2006年 | 375篇 |
2005年 | 344篇 |
2004年 | 267篇 |
2003年 | 245篇 |
2002年 | 123篇 |
2001年 | 47篇 |
2000年 | 30篇 |
1999年 | 21篇 |
1998年 | 21篇 |
1997年 | 8篇 |
1996年 | 12篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 7篇 |
1991年 | 7篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1988年 | 7篇 |
1987年 | 3篇 |
1985年 | 8篇 |
1984年 | 8篇 |
1983年 | 3篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 3篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1972年 | 3篇 |
1969年 | 2篇 |
排序方式: 共有9257条查询结果,搜索用时 15 毫秒
61.
Hafiz Muhammad Shoaib Ambreen Gul Muazzam Asif Mir Suk-Yul Jung Abdul Matin 《Parasitology research》2013,112(3):1179-1188
Acanthamoeba is an opportunistic protozoan pathogen and known to be one of the most ubiquitous organisms, play a vital role in ecosystem, and recognized to cause blinding keratitis and rare but fatal granulomatous encephalitis involving the central nervous system with a very poor prognosis. This is due to limited availability of effective anti-Acanthamoeba drugs. The objective of the present study was to determine the efficacy of methanolic plants crude extracts on the viability and biological properties of Acanthamoeba castellanii (T4 genotype) and its cytotoxic effects on human corneal epithelial cells (HCEC). Using HCEC, it was observed that Acanthamoeba exhibited binding (>90 %) and cytotoxicity (>80 %) to host cells. However, plant crude extracts remarkably inhibited more than 70 and 60 % of Acanthamoeba binding and cytotoxicity to HCEC, respectively. It was further established that crude extracts (ranging from 0.1 to 1.5 mg/ml) exhibited amoebicidal effects, i.e., >50 % of trophozoites were killed/reduced at maximum dose (1.5 mg/ml) within 1 h incubation. However, the residual subpopulation remained static over longer incubations. Furthermore, growth assay demonstrated crude extracts inhibited >50 % Acanthamoeba numbers up to 7 days. Our results confirmed that plant crude extracts has inhibitory effects on Acanthamoeba growth and viability. Overall, these findings revealed that tested plant extracts is inhibitory to Acanthamoeba properties associated with pathogenesis. To the best of our knowledge, our findings demonstrated for the first time that selected methanol plant crude extracts exhibits inhibitory effects on biological properties of Acanthamoeba without any toxic effects on HCEC cells in vitro. 相似文献
62.
Ashley Woolbert Emily R. Calasanz Muhammad Nazim 《International journal of surgery case reports》2013,4(12):1061-1063
INTRODUCTIONLumbar herniation is uncommon, with traumatic etiology being rare. Traumatic lumbar hernias are usually caused by seatbelt injury in motor vehicle accidents. It is exceedingly uncommon to see lumbar hernias in an unrestrained passenger of a motor vehicle accident.PRESENTATION OF CASEWe present a case of a traumatic inferior lumbar hernia in a young woman who was an unrestrained driver of a vehicle involved in a high-speed collision, with multiple rollover and ejection. CT scans of the abdomen and pelvis suggested soft tissue injury involving muscles in the left lower posterior flank with traumatic herniation of the colon and small bowel. Emergent midline abdominal laparotomy confirmed herniation in the left lower quadrant. After abdominal closure, in the prone position, an extensive laceration over the left flank also confirmed herniation. Due to its dirty nature, the wound was irrigated, lavaged and covered with wound vacuum-assisted closure placement. The decision was made in favor of delayed elective hernia repair.DISCUSSIONLumbar hernias are usually caused by sudden force to the abdomen, leading to increased intra-abdominal pressure. This pressure combined with areas of weakness in the superior and/or inferior triangle lead to herniation. Uncommonly, the contents of lumbar hernias can strangulate or incarcerate leading to bowel obstruction. This can often be prevented by detection with CT and laparotomy.CONCLUSIONLumbar herniation of traumatic etiology is rare. Early detection with CT and/or exploratory laparotomy is important to avoid increases in size of the defect and bowel strangulation and incarceration. 相似文献
63.
64.
Phenotypic and genotypic characterization of enteroaggregative Escherichia coli isolates from pediatric population in Pakistan
下载免费PDF全文
![点击此处可从《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Uzma Khalil Mahwish Younus Naeem Asghar Fariha Siddiqui Oscar G. Gómez‐Duarte Brendan W. Wren Habib Bokhari 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(10):872-880
Enteroaggregative Escherichia coli (EAEC) are a leading cause of diarrhea among children. The objective of this study was to define the frequency of EAEC among diarrheal children from flood‐affected areas as well as sporadic cases, determine multidrug resistance, and evaluation of virulence using an in vivo model of pathogenesis. Stool samples were collected from 225 diarrheal children from 2010 to 2011 from flood‐affected areas as well as from sporadic cases in Pakistan. Identified EAEC isolates were characterized by phylogrouping, antibiotic resistance patterns including the extended‐spectrum beta lactamase spectrum, single nucleotide polymorphism detection in gyrA and parC, and virulence potential using wax worm, G. mellonella. A total of 35 (12.5%) confirmed EAEC isolates were identified among 225 E. coli isolates. EAEC isolates displayed high resistance to tetracycline, ampicillin, and cefaclor. A total of 34.28% were ESBL positive. Single nucleotide polymorphism detection revealed 37.14% and 68.57% isolates were positive for SNPs in gyrA (A660‐T660) and parC (C330‐T330), respectively. Phylogrouping revealed that B2 phylogroup was more prevalent among all EAEC isolates tested followed by D, A, B1, and non‐typeable (NT). Infection of G. mellonella with EAEC showed that killing infective dose was 100% higher than E. coli DH5 alpha control. EAEC are prevalent among Pakistani children with diarrhea, they are highly resistant to antibiotics, and predominantly fall into B2 phylogroup. Epidemiologic surveillance of EAEC and other E. coli pathotypes is critical to assess not only the role of these pathogens in diarrheal disease but also to determine the extent of multidrug resistance among the population. 相似文献
65.
目的:评估助视器对年龄相关性黄斑变性(AMD)患者视功能恢复和阅读速度的影响。方法:对低视力门诊44名AMD患者进行评估。收集并分析使用助视器前和使用助视器时裸眼视力、最佳矫正视力、屈光状态、助视器类型(LVAs)以及阅读速度的相关数据。结果:共44例AMD患者,平均年龄为73±10.8岁,男性36例(82%)。其中,29例(67%)受试者视力较好的眼远视力(DVA)为1.0~1.6 LogMAR,而36例(82%)受试者近视力(NVA)小于3.2 m。使用助视器时平均DVA提高0.67±0.27 LogMAR(P=0.000)。使用LVAs时,42例患者NVA达到1 m甚至更佳,仅有2例(4.5%)没有使用LVAs的患者NVA为1 m。在使用一定时间的助视器后,有阅读能力的患者平均阅读速度从每分钟2.9±4.78字提高到每分钟71.31±29.96字(P<0.001)。15名受试者远距离视觉使用单目望远镜,而戴高倍单目镜片眼镜作为最常用的阅读辅助工具。结论:LVAs对AMD患者的视功能恢复和阅读能力的提高有一定的作用。对于AMD患者而言,接受低视力护理服务是有必要的。 相似文献
66.
67.
Muhammad Khurram Khan Mohammed Zakariah Hafiz Malik Kim-Kwang Raymond Choo 《The Australian journal of forensic sciences》2018,50(5):525-542
Today, digital multimedia (audio, video, images) is a common evidential source in litigation and criminal justice proceedings, and, not surprisingly, multimedia forensics is an active research area. One particular challenge faced by multimedia forensic researchers is the lack of a comprehensive and publicly available data-set for evaluating existing and new algorithms. This paper presents a digital audio forensic data-set, designed to facilitate evaluation of audio forensic algorithms (e.g. microphone identification, acoustic environment identification and splice detection). This paper also briefly describes the data-collection settings, microphones, speakers, languages and notations used. Existing tamper-detection techniques rely on artefacts due to recording devices, codec and/or the acoustic environment in the audio in question. Experimental results show that the selected approaches achieved promising results. 相似文献
68.
69.
Muhammad Jamal PhD 《Behavioral medicine (Washington, D.C.)》2013,39(2):60-68
Abstract This study examined Type A and Type B differences in job performance, psychosomatic complaints, and career progression among white-collar employees (N = 218) in a field setting. Significant differences were found between Type A's and Type B's in quality of performance, effort exerted at the job, and psychosomatic complaints. Employees' cultural background and sex moderated some of the relationships observed in the study. Implications of the findings for future research on the topic are discussed. 相似文献
70.