全文获取类型
收费全文 | 247篇 |
免费 | 24篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 6篇 |
妇产科学 | 12篇 |
基础医学 | 36篇 |
口腔科学 | 6篇 |
临床医学 | 28篇 |
内科学 | 55篇 |
皮肤病学 | 1篇 |
神经病学 | 22篇 |
特种医学 | 11篇 |
外科学 | 18篇 |
综合类 | 16篇 |
预防医学 | 16篇 |
眼科学 | 15篇 |
药学 | 10篇 |
肿瘤学 | 17篇 |
出版年
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 1篇 |
2019年 | 5篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 6篇 |
2014年 | 7篇 |
2013年 | 5篇 |
2012年 | 15篇 |
2011年 | 15篇 |
2010年 | 10篇 |
2009年 | 9篇 |
2008年 | 15篇 |
2007年 | 8篇 |
2006年 | 8篇 |
2005年 | 11篇 |
2004年 | 10篇 |
2003年 | 4篇 |
2002年 | 7篇 |
2001年 | 9篇 |
2000年 | 11篇 |
1999年 | 8篇 |
1998年 | 4篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 9篇 |
1990年 | 6篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1977年 | 1篇 |
1974年 | 4篇 |
1973年 | 1篇 |
1972年 | 4篇 |
1970年 | 2篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1941年 | 2篇 |
排序方式: 共有271条查询结果,搜索用时 15 毫秒
1.
The Johns Hopkins Wilmer Eye Institute and the NASA Stennis Space Center are collaborating on the development of a new high technology low vision aid called the Low Vision Enhancement System (LVES). The LVES consists of a binocular head-mounted video display system, video cameras mounted on the head-mounted display, and real-time video image processing in a system package that is battery powered and portable. Through a phased development approach, several generations of the LVES can be made available to the patient in a timely fashion. This paper describes the LVES project with major emphasis on technical problems encountered or anticipated during the development process. 相似文献
2.
Microarray based comparative genomic hybridisation (array-CGH) detects submicroscopic chromosomal deletions and duplications in patients with learning disability/mental retardation and dysmorphic features 总被引:24,自引:2,他引:24 下载免费PDF全文
Shaw-Smith C Redon R Rickman L Rio M Willatt L Fiegler H Firth H Sanlaville D Winter R Colleaux L Bobrow M Carter NP 《Journal of medical genetics》2004,41(4):241-248
The underlying causes of learning disability and dysmorphic features in many patients remain unidentified despite extensive investigation. Routine karyotype analysis is not sensitive enough to detect subtle chromosome rearrangements (less than 5 Mb). The presence of subtle DNA copy number changes was investigated by array-CGH in 50 patients with learning disability and dysmorphism, employing a DNA microarray constructed from large insert clones spaced at approximately 1 Mb intervals across the genome. Twelve copy number abnormalities were identified in 12 patients (24% of the total): seven deletions (six apparently de novo and one inherited from a phenotypically normal parent) and five duplications (one de novo and four inherited from phenotypically normal parents). Altered segments ranged in size from those involving a single clone to regions as large as 14 Mb. No recurrent deletion or duplication was identified within this cohort of patients. On the basis of these results, we anticipate that array-CGH will become a routine method of genome-wide screening for imbalanced rearrangements in children with learning disability. 相似文献
3.
4.
Demichelis F Setlur SR Banerjee S Chakravarty D Chen JY Chen CX Huang J Beltran H Oldridge DA Kitabayashi N Stenzel B Schaefer G Horninger W Bektic J Chinnaiyan AM Goldenberg S Siddiqui J Regan MM Kearney M Soong TD Rickman DS Elemento O Wei JT Scherr DS Sanda MA Bartsch G Lee C Klocker H Rubin MA 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(17):6686-6691
5.
ObjectivesTo establish whether simplified adhesives (self-etch) are as clinically effective as conventional adhesives (etch-and-rinse) with multiple application steps for treatment of non-carious cervical lesions (NCCLs).Null hypothesis: there is no difference in the clinical effectiveness of the four different bonding strategies: Three-step etch-and-rinse; Two-step etch-and-rinse; Two-step self-etch; One-step self-etch for treatment of NCCLs.SourcesElectronic databases were searched including: Cochrane Oral Health Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. In addition, studies were identified by handsearching of selected journals.Study selectionRandomised controlled trials (RCTs) comparing at least two adhesives in non-carious cervical lesions (NCCLs), with at least 18 months follow-up were selected. The primary outcome was loss of retention/restoration loss, with marginal adaptation and marginal discolouration as secondary outcomes. Criteria for quality assessment included: random sequence generation; allocation concealment; blinding of outcome assessment; and information on withdrawals. Twenty six studies were identified that met the inclusion criteria. In general, studies were not of sufficient quality to fully address the objectives of this review.ConclusionThere is not enough evidence to support one adhesive or bonding strategy over another for treatment of NCCLs. Consequently, the null hypothesis of no difference cannot be supported or rejected with the data currently available. There is a need for better standardisation and reporting of randomised controlled trials investigating adhesive performance.Clinical significanceStudies with low overall risk of bias demonstrated good clinical performance for adhesives with all four bonding strategies. However, included studies showed wide variation between adhesives of the same category. 相似文献
6.
Sirolimus is an immunosuppressive medication used in transplant recipients. To our knowledge, we describe the third reported case of alveolar hemorrhage in association with sirolimus. Fever, dyspnea, hemoptysis, and lung infiltrates resolved rapidly with cessation of sirolimus therapy both initially and after reinstitution of the drug. Unlike previous reports, our patient had no evidence of lymphocytic alveolitis but rather marked macrophage hemosiderosis, suggesting that sirolimus pulmonary toxicity may manifest through 2 separate mechanisms. Our case highlights an uncommon but potentially lethal manifestation of sirolimus pulmonary toxicity. 相似文献
7.
8.
Oge Arum Dustin J. Rickman John J. Kopchick Andrzej Bartke 《Age (Dordrecht, Netherlands)》2014,36(1):117-127
Neuromusculoskeletal (physical) frailty is an aging-attributable biomedical issue of extremely high import, from both public health and individual perspectives. Yet, it is rarely studied in nonhuman research subjects and very rarely studied in animals with extended longevity. In an effort to address this relatively neglected area, we have conducted a longitudinal investigation of the neuromusculoskeletal healthspan in mice with two senescence-slowing interventions: growth hormone (GH) resistance, produced by GH receptor “knockout” (GHR-KO), and caloric restriction (CR). We report marked improvements in the retention of strength, balance, and motor coordination by the longevity-conferring GHR/BP gene disruption, CR regimen, or a combination of the two. Specifically, GHR-KO mice exhibit superior grip strength, balance, and motor coordination at middle age, and CR mice display superior grip strength at middle age. The advantageous effects established by middle-age are more pronounced in old-age, and these robust alterations are, generally, not gender-specific. Thus, we show that genetic and/or dietary interventions that engender longevity are also beneficial for the retention of neuromusculoskeletal health and functionality. The translational knowledge to be gained from subsequent molecular or histological investigations of these models of preserved functionality and decelerated senescence is potentially relevant to the efforts to reduce the specter of fear, falls, fracture, and frailty in the elderly. 相似文献
9.
艾滋病合并隐球菌脑膜炎18例临床分析 总被引:6,自引:1,他引:6
目的 提高对艾滋病 (AIDS)合并隐球菌脑膜炎的认识。方法 对赤道几内亚巴塔地区医院 18例AIDS合并隐球菌脑膜炎患者进行临床综合分析。结果 18例AIDS合并隐球菌脑膜炎患者的临床主要表现为 :发热、剧烈头痛、极度乏力、肢体痛、脑膜刺激征及消瘦与脱水等。脑脊液 (CSF)培养均为新型隐球菌生长 ;涂片及隐球菌多糖荚膜抗原 (ELISA法 )检测的阳性率分别为 77 8% (14/ 18) ,94 4% (17/ 18)。结论 隐球菌脑膜炎为AIDS常见机会性感染及主要致死病因之一。 相似文献
10.
Lucie MT Byrne-Davis Peter Salmon Katja Gravenhorst Tim OB Eden Bridget Young 《BMC medical research methodology》2010,10(1):101