全文获取类型
收费全文 | 21197篇 |
免费 | 1317篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 202篇 |
儿科学 | 760篇 |
妇产科学 | 614篇 |
基础医学 | 2578篇 |
口腔科学 | 211篇 |
临床医学 | 4052篇 |
内科学 | 3537篇 |
皮肤病学 | 362篇 |
神经病学 | 1807篇 |
特种医学 | 348篇 |
外科学 | 1896篇 |
综合类 | 173篇 |
一般理论 | 34篇 |
预防医学 | 2812篇 |
眼科学 | 216篇 |
药学 | 1369篇 |
2篇 | |
中国医学 | 7篇 |
肿瘤学 | 1565篇 |
出版年
2023年 | 132篇 |
2022年 | 188篇 |
2021年 | 440篇 |
2020年 | 300篇 |
2019年 | 456篇 |
2018年 | 543篇 |
2017年 | 448篇 |
2016年 | 468篇 |
2015年 | 515篇 |
2014年 | 681篇 |
2013年 | 1035篇 |
2012年 | 1567篇 |
2011年 | 1537篇 |
2010年 | 865篇 |
2009年 | 791篇 |
2008年 | 1417篇 |
2007年 | 1547篇 |
2006年 | 1516篇 |
2005年 | 1414篇 |
2004年 | 1381篇 |
2003年 | 1269篇 |
2002年 | 1184篇 |
2001年 | 173篇 |
2000年 | 119篇 |
1999年 | 157篇 |
1998年 | 245篇 |
1997年 | 192篇 |
1996年 | 196篇 |
1995年 | 168篇 |
1994年 | 159篇 |
1993年 | 124篇 |
1992年 | 94篇 |
1991年 | 92篇 |
1990年 | 81篇 |
1989年 | 66篇 |
1988年 | 86篇 |
1987年 | 78篇 |
1986年 | 82篇 |
1985年 | 68篇 |
1984年 | 63篇 |
1983年 | 44篇 |
1982年 | 69篇 |
1981年 | 76篇 |
1980年 | 71篇 |
1979年 | 34篇 |
1978年 | 41篇 |
1977年 | 31篇 |
1976年 | 25篇 |
1974年 | 27篇 |
1973年 | 27篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Tony Hope Kathleen M. Tilling Kathy Gedling Janet M. Keene Sandra D. Cooper Christopher G. Fairburn 《International journal of geriatric psychiatry》1994,9(2):149-155
‘Wandering’ is one of the most troublesome of behavioural problems in dementia. The term ‘wandering’ covers many different types of behaviour. We examined the hypothesis that the different types of wandering behaviour seen in dementia from a scale using data collected on 83 elderly subjects suffering from either Alzheimer's disease or multiinfarct dementia. We reject the scaling hypothesis. Our data suggest that there are three main categories of wandering behaviour, and that one of these categories is usefully divided into four subcategories. 相似文献
22.
Larry E. Davis Mario Kornfeld Herbert S. Mooney Kurt J. Fiedler Kathleen Y. Haaland William W. Orrison Elsa Cernichiari Thomas W. Clarkson 《Annals of neurology》1994,35(6):680-688
For 3 months in 1969 a family in the United States that included a pregnant mother consumed pork containing methylmercury. Children, aged 20, 13, and 8 years and a neonate, developed severe neurological signs. Twenty-two years later, the 2 oldest had cortical blindness or constricted visual fields, diminished hand proprioception, choreoathetosis, and atentional deficits. Magnetic resonance images showed tissue loss in the calcarine and parietal cortices and cerebellar folia. The youngest had quadriplegia, blindness, and severe mental retradation until their deaths. The brain of the 8-year-old who died at age 30 showed cortical atrophy, neuronal loss, and gliosis, most pronounced in the paracentral and parietooccipital regions. The total mercury level in formalin-fixed, left occipital cortex was 1,974 ng/gm as measured by atomic absorption. Regional brain mercury levels correlated with extent of brain damage. A control patient had 38.5 ng of mercury/gm in the occipital cortex. Systemic organs in the patient and a control subject had comparable mercury levels. In mercury-intoxicated rats, we found that only 5 to 10% of total brain mercury was lost by formalin fixation. Brain inorganic mercury in the patient ranged from 82 to 100%. Since inorganic mercury crosses the blood-brain barrier poorly, biotransformation of methyl to inorganic mercury may have occurred after methylmercury crossed the blood-brain barrier, accounting for its persistence in brain and causing part of the brain damage. 相似文献
23.
On inpatient psychiatric units, nurses control the tone, pace, and activity level of the environment. But under the influence of factors such as high patient acuity and negative group contagion, a milieu can become unacceptably loud and chaotic. A volatile milieu is a potentially dangerous environment because patients' anxiety and agitation can quickly lead to acting out and aggression. This article focuses on how nurses can regain control of a milieu spiralling into chaos by tightening the structure of the routine, anticipating potential problems, and maintaining a confident calm manner. The charge nurse orchestrates the staff group's response to escalation through detailed planning, decisive interventions, and strategic use of every available resource. 相似文献
24.
25.
A new track etch autoradiographic technique for quantitating boron-10 containing compounds used for neutron capture therapy is described. Instead of applying solutions of Cs2B12H11SH and its oxidation products directly to solid-state nuclear track detectors, diethylaminoethyl cellulose thin layer chromatography (TLC) plates are utilized as sample matrices. The plates are juxtaposed with Lexan polycarbonate detectors and irradiated in a beam of thermal neutrons. The detectors are then chemically etched, and the resultant tracks counted with an optoelectronic image analyzer. Sensitivity to boron-10 in solution reaches the 1 pg/microliter level, or 1 ppb. In heparinized blood samples, 100 pg boron-10/microliter are detected. This TLC matrix method has the advantage that sample plates can be reanalyzed under different reactor conditions to optimize detector response to the boron-10 carrier material. Track etch/TLC allows quantitation of the purity of boron neutron capture therapy compounds by utilizing the above method with TLC plates developed in solvent systems that resolve Cs2B12H11SH and its oxidative analogs. Detectors irradiated in juxtaposition to the thin layer chromatograms are chemically etched, and the tracks are counted in the sample lane from the origin of the plate to the solvent front. A graphic depiction of the number of tracks per field yields a quantitative analysis of compound purity. 相似文献
26.
27.
Devang N Patel Francis D Pagani Todd M Koelling David B Dyke Ragavendra R Baliga Robert J Cody Kathleen D Lake Keith D Aaronson 《The Journal of heart and lung transplantation》2002,21(2):204-210
BACKGROUND: Pravastatin and simvastatin prolong survival and reduce transplant-related coronary vasculopathy, although low-density lipoprotein (LDL) lowering with these agents is only modest. The objective of this study was to assess the safety of moderate dose atorvastatin and its efficacy when prior treatment with another statin had failed to lower LDL to < 100 mg/dl. METHODS: Data from 185 patients were retrospectively evaluated for adverse events, duration of exposure (person-days), and the mean atorvastatin dose exposure. Changes in lipid parameters, and prednisone and cyclosporine doses were determined. RESULTS: Safety: 48 patients received atorvastatin for 24,240 person-days at a mean dose exposure of 21 +/- 10 mg. Rhabdomyolysis, myositis, myalgias, and hepatotoxicity occurred in 0, 2, 2, and 0 patients, respectively. All events occurred at the 10-mg dose, within the first 3 months, and were rapidly reversible with atorvastatin discontinuation. Efficacy: Thirty-four patients evaluable for efficacy analyses had a pre-atorvastatin LDL of 145 +/- 38 mg/dl on the following statins: pravastatin (n = 30, 40 +/- 0mg), fluvastatin (n = 3, 33 +/- 12 mg), simvastatin (n = 1, 40 mg). After atorvastatin (21 +/- 9 mg/day) for 133 +/- 67 days, LDL was reduced to 97 +/- 24 mg/dl (relative reduction 31 +/- 20%, p < 0.0001). At the end of the observation period (418 +/- 229 days, atorvastatin final dose 24 +/- 14 mg/day), LDL was further decreased to 88 +/- 23 mg (relative reduction 37 +/- 17%, p < 0.0001). CONCLUSION: Atorvastatin, when used at moderate doses and with close biochemical and clinical monitoring, appears to be safe and is effective in aggressively lowering LDL in heart transplant recipients when treatment with other statins has failed to achieve LDL goals. 相似文献
28.
Reinherz Helen Gordon Alan L. Morris Kathleen M. Anastas Jeane W. 《The journal of primary prevention》1983,4(2):73-95
Journal of Prevention - The major issues involved in the design and implementation of effective school screening programs are addressed, using data from a longitudinal study following over 500... 相似文献
29.
30.
J A Noonan E P Todd S Norman C B Bacdayan L J Swift R J Mier J F Kilner J Engelberg 《Southern medical journal》1987,80(8):1016-1023
We discuss the ethical, psychosocial, economic, and medical dimensions of the treatment and management of a child with Down's syndrome and a congenital heart defect. 相似文献