全文获取类型
收费全文 | 1043篇 |
免费 | 78篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 21篇 |
妇产科学 | 5篇 |
基础医学 | 86篇 |
口腔科学 | 24篇 |
临床医学 | 177篇 |
内科学 | 272篇 |
皮肤病学 | 20篇 |
神经病学 | 54篇 |
特种医学 | 116篇 |
外科学 | 70篇 |
综合类 | 70篇 |
预防医学 | 79篇 |
眼科学 | 28篇 |
药学 | 55篇 |
1篇 | |
中国医学 | 19篇 |
肿瘤学 | 26篇 |
出版年
2022年 | 7篇 |
2021年 | 15篇 |
2020年 | 15篇 |
2019年 | 21篇 |
2018年 | 21篇 |
2017年 | 12篇 |
2016年 | 12篇 |
2015年 | 35篇 |
2014年 | 30篇 |
2013年 | 43篇 |
2012年 | 48篇 |
2011年 | 43篇 |
2010年 | 56篇 |
2009年 | 37篇 |
2008年 | 44篇 |
2007年 | 45篇 |
2006年 | 24篇 |
2005年 | 25篇 |
2004年 | 29篇 |
2003年 | 31篇 |
2002年 | 34篇 |
2001年 | 20篇 |
2000年 | 19篇 |
1999年 | 21篇 |
1998年 | 33篇 |
1997年 | 25篇 |
1996年 | 35篇 |
1995年 | 25篇 |
1994年 | 28篇 |
1993年 | 18篇 |
1992年 | 13篇 |
1991年 | 12篇 |
1990年 | 16篇 |
1989年 | 23篇 |
1988年 | 30篇 |
1987年 | 15篇 |
1986年 | 17篇 |
1985年 | 18篇 |
1984年 | 15篇 |
1983年 | 8篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 13篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1976年 | 14篇 |
1975年 | 7篇 |
1974年 | 6篇 |
1971年 | 4篇 |
1930年 | 4篇 |
排序方式: 共有1127条查询结果,搜索用时 15 毫秒
1.
R M Packard 《Social science & medicine (1982)》1989,28(5):475-496
Industrial development in Africa has carried with it significant health costs. These costs are normally defined rather narrowly by those concerned about occupational or industrial health and safety and refer only to the health consequences of worker exposure to specific hazardous processes, materials or environmental conditions associated with the workplace. A more comprehensive measurement of industrial health costs, however, must also include an assessment of the impact which industrial development and the creation of an industrial workforce has on ecological relationships, environmental conditions and patterns of sickness and health in the areas surrounding industrial centers. Traditional definitions of occupational health also tend to focus attention on the immediate causal linkages which exist between the development of particular industrial processes and specific health hazards. Yet any attempt to fully understand the causes of industrial health problems in Africa must look beyond these immediate causal linkages and examine the wider political and economic forces which determine the shape of industrial development and the extent to which the health costs of this development are borne by industrial workers and their families, as well as by people who may not be directly or even indirectly connected to industrial development, but may, nonetheless, be exposed to its health risks. The paper surveys the direct and indirect health costs of mining, large scale agriculture, and manufacturing in Africa and examines the economic and political interests which have determined the distribution of these costs. 相似文献
2.
Anstey NM Stewart LM Packard M Graney WF Bartlett JA 《International journal of antimicrobial agents》1996,6(4):183-187
RMP-7, a nine-amino acid bradykinin analogue, has been shown in animals to temporarily increase the permeability of the blood brain barrier to small molecules including amphotericin B, when administered intravenously. We sought to evaluate the safety of escalating doses of RMP-7 administered to human volunteers with the acquired immune deficiency syndrome (AIDS). Six HIV antibody-positive adults with CD4+ cell counts <50/mm3 received three increasing doses of RMP-7 on successive days: 30 ng/kg, 100 ng/kg and 300 ng/kg infused over 2, 2 and 10 min, respectively. Adverse experiences were dose-related, mild-moderate in intensity, primarily related to vasodilation and resolved rapidly without sequelae. Mean maximum increases in pulse rate at 30 ng/kg, 100 ng/kg and 300 ng/kg were 4.0, 7.8 and 28.2 beats per min, respectively. The maximum changes in average mean arterial pressure were +7.7, +5.6 and −0.2 mmHg from baseline, respectively. Minor increases in liver enzymes were noted in three patients, all with pre-existing enzyme elevations. Despite the high frequency of both occult and overt cardiovascular abnormalities in advanced HIV infection, RMP-7 is shown to be safe in this group of AIDS patients at all dosage levels tested, with adverse effects similar to previous experience in healthy humans. 相似文献
3.
Data from the Social Security Administration's 1982 New Beneficiary Survey and Master Beneficiary Record were matched with 1984 data from the Medicare Automated Data Retrieval System to study the effects of self-reported health on subsequent health service usage and survival. Proportionately, more new retired workers who reported poorer health in 1982 were decreased by December 1984. Functionally dependent beneficiaries as determined by the Functional Capacity Limitation Index had death rates four to five times greater than those who reported no limitations. The health status of retired workers who received Social Security benefits before age 65 was no better than beneficiaries 65 or over. Decedents were more likely than survivors to incur Medicare charges, and to have substantially higher median charges--$8,834 compared with $285. 相似文献
4.
目的:采用HPLC法测定四川粉葛中葛根素的含量。方法:色谱柱为依利特C18柱(4.6min&;#215;150mm,5μm),流动相为甲醇-水(25:75),流速为0.8ml/min,检测波长为250nm,柱温为25℃。结果:葛根素在0.0880~0.7040μg范围内峰面积与进样量呈良好的线性关系,回归方程为A=336.35X-1.7716,r=1.0000,其平均同收率为100.01%,RSD为0.14%(n=6)。结论:该方法简便易行,结果准确,可用于四川粉葛药材的质量控制。 相似文献
5.
6.
寰椎椎弓根螺钉置钉技巧探讨 总被引:2,自引:0,他引:2
[目的]探讨寰椎椎弓根螺钉固定治疗寰枢椎不稳的置钉技巧。[方法]总结2000年10月~2008年9月应用寰椎椎弓根螺钉技术治疗寰枢椎不稳患者66例,置钉132枚。术中在直视下依据手感行寰椎椎弓根螺钉置钉,复位固定。[结果]本组66例132枚螺钉均成功置入,复位固定满意。术中未发现脊髓、神经根、椎动脉等损伤。术后患者症状及神经脊髓功能均有不同程度恢复。96枚螺钉术后行CT检查,其中91枚位置良好(94.89%)。全部病例内固定无松动、断裂,植骨均融合。[结论]术前影像学测量,术中显露寰椎后弓、直视下依据手感置钉、X线确定进钉方向,是安全置钉的技巧。 相似文献
7.
目的 探索HO-1对肝脏缺血再灌注损伤中肥大细胞脱颗粒的影响。方法 将20只SD大鼠随机分成4组:假手术组(Sham组),缺血再灌注损伤组(I/RI组),HO-1诱导剂钴原卟啉组(CoPP组,术前24h给予CoPP,5 mg/kg)及HO-1抑制剂锌原卟啉组(ZnPP组,术前24h给予ZnPP,20 mg/kg)。建立大鼠缺血再灌注损伤模型,各组于再灌注后2h收集标本。RT-PCR检测肝脏组织HO-1 mRNA表达,Western blot检测肝脏组织HO-1蛋白表达;测定血清中ALT、AST水平;肝脏组织甲苯胺蓝染色检测肥大细胞脱颗粒数量,HE染色评价肝脏组织损伤情况。结果 与Sham组相比,I/RI组、CoPP组、ZnPP组大鼠组织HO-1 RNA和蛋白表达增加,血清ALT、AST水平升高,肥大细胞脱颗粒数量增多,肝脏细胞损伤加重。CoPP组与I/RI组相比,HO-1 mRNA和蛋白表达增加,血清ALT、AST水平减低,肥大细胞脱颗粒数量减少,肝细胞损伤减轻。ZnPP组与I/RI组相比,HO-1 mRNA和蛋白表达减少,血清ALT、AST水平升高,肥大细胞脱颗粒数量增多、肝细胞损伤严重。组间比较差异具有统计学意义(P<0.05)。结论 HO-1过表达能减轻肝脏I/RI,其机制可能与抑制肝脏组织中肥大细胞脱颗粒有关。 相似文献
8.
Packard AB Kronauge JF Barbarics E Kiani S Treves ST 《Nuclear medicine and biology》2002,29(3):289-294
The lipophilic, monocationic copper(II) complex of the diiminedioxime ligand 2,10-di-n-butyl-3,9-dimethyl-1,4,8,11-tetraazaundeca-1,3,8,10-tetraen-1,11-dione dioxime was synthesized and labeled with 64Cu. The biological properties of the 64Cu-labeled complex were measured in vivo and in vitro. In vivo, the complex shows uptake by the heart similar to that of 99mTc-tetrofosmin. In vitro, its uptake by multidrug resistant and non-resistant MES-SA tumor cells parallels that of 99mTc-MIBI, a well-characterized marker of multidrug resistance. These results suggest that this class of copper complexes may form the basis for the development of a 64Cu PET radiopharmaceutical for the functional imaging of multidrug resistance and/or myocardial perfusion. 相似文献
9.
The association between possession of the APOE epsilon4 allele and unfavourable outcome after traumatic brain injury (TBI) suggests that the apolipoprotein E protein (apoE) plays a key role in the response of the human brain to injury. ApoE is known to regulate cholesterol metabolism in the periphery through its action as a ligand for receptor mediated uptake of lipoprotein particles (Lps). Greater understanding of cholesterol metabolism in the human central nervous system may identify novel treatment strategies applicable to acute brain injury. We report findings from the analysis of lipoproteins in the cerebrospinal fluid (CSF) of patients with TBI and non-injured controls, testing the hypothesis that remodeling of CSF lipoproteins reflects the response of the brain to TBI. CSF Lps were isolated from the CSF of controls and patients with severe TBI by size exclusion chromatography, and the lipoprotein fractions analysed for cholesterol, phospholipid, apoAI, and apoE. There was a marked decrease in apoE containing Lps in the TBI CSF compared to controls (p=0.002). After TBI there was no significant decrease in apoAI containing CSF Lps (CSF LpAI), but the apoAI resided on smaller sized particles than in control CSF. There was a population of very small sized Lps in TBI CSF, which were associated with the increased cholesterol (p=0.0001) and phospholipid (p=0.040) seen after TBI. The dramatic loss of apoE containing Lps from the CSF, and the substantial increase in CSF cholesterol, support the concept that apoE and cholesterol metabolism are intimately linked in the context of acute brain injury. Treatment strategies targeting CNS lipid transport, required for neuronal sprouting and synaptogenesis, may be applicable to traumatic brain injury. 相似文献
10.