全文获取类型
收费全文 | 427篇 |
免费 | 44篇 |
国内免费 | 13篇 |
专业分类
儿科学 | 14篇 |
妇产科学 | 7篇 |
基础医学 | 54篇 |
口腔科学 | 7篇 |
临床医学 | 66篇 |
内科学 | 115篇 |
皮肤病学 | 38篇 |
神经病学 | 12篇 |
特种医学 | 82篇 |
外科学 | 22篇 |
综合类 | 2篇 |
预防医学 | 16篇 |
眼科学 | 2篇 |
药学 | 26篇 |
中国医学 | 1篇 |
肿瘤学 | 20篇 |
出版年
2023年 | 5篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 3篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 10篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 9篇 |
2012年 | 11篇 |
2011年 | 18篇 |
2010年 | 10篇 |
2009年 | 10篇 |
2008年 | 11篇 |
2007年 | 18篇 |
2006年 | 11篇 |
2005年 | 14篇 |
2004年 | 9篇 |
2003年 | 14篇 |
2002年 | 8篇 |
2001年 | 8篇 |
2000年 | 5篇 |
1999年 | 14篇 |
1998年 | 25篇 |
1997年 | 19篇 |
1996年 | 16篇 |
1995年 | 15篇 |
1994年 | 13篇 |
1993年 | 11篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 17篇 |
1988年 | 27篇 |
1987年 | 11篇 |
1986年 | 9篇 |
1985年 | 4篇 |
1984年 | 7篇 |
1983年 | 5篇 |
1982年 | 12篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1979年 | 6篇 |
1978年 | 3篇 |
1977年 | 8篇 |
1976年 | 7篇 |
1975年 | 5篇 |
1939年 | 2篇 |
1916年 | 1篇 |
排序方式: 共有484条查询结果,搜索用时 15 毫秒
41.
Hermann Faller Gunter F. Koch Andrea Reusch Paul Pauli Hubert Allgayer 《Patient education and counseling》2009
Objective
Although patient education may enhance knowledge, coping with illness, and quality of life among cancer patients, it is uncertain which didactic method is most effective. We compared the impact of an interactive, patient-oriented group program to a lecture-based, information-only program in gastric cancer patients.Methods
In this prospective, controlled trial, 121 gastric cancer patients attending inpatient rehabilitation after surgical treatment received either the interactive intervention or lectures providing information. The outcomes were patients’ disease-related knowledge, active coping with illness, and quality of life (QoL) at the end of their stay and 6 and 12 months thereafter.Results
Both groups improved their knowledge and QoL during rehabilitation; however, knowledge was significantly higher in the interactive group compared to the lecture group. This difference was maintained at the 6- and 12-months follow-ups. In addition, the interactive group proved superior to the lecture group regarding active coping with illness and QoL at the end of rehabilitation, but not during follow-up.Conclusions
A structured, interactive patient education program proved superior to lecture-based provision of information in regards to short-term and long-term knowledge as well as short-term coping and QoL.Practice implications
In gastric cancer patients, interactive patient education seems preferable over lectures. 相似文献42.
Structural abnormalities of the X chromosome are rarely found in neoplastic disorders. We describe three patients with a history of idiopathic acquired sideroblastic anemia (IASA); each one had an abnormal clone of cells in the bone marrow, characterized by a structurally abnormal X chromosome. In two of these patients, the predominant karyotype was 47,X,2idic(X)(q13); in the other patient, it was 46,X,t(X;11)(q13;p15). Inasmuch as all three of these cases involved chromosome band Xq13, as did two previously published cases, we suggest that band Xq13 may be more prone to structural rearrangement than other X chromosome bands in hematologic disorders. The common Xq13 chromosome breakpoint and clinical presentation (IASA) among these three patients and the occurrence of an X-linked type of sideroblastic anemia may suggest that an association exists between X chromosome abnormalities and IASA. Perhaps alteration of a gene or chromosome structure in or near band Xq13 predisposes to development of IASA. The fact that two of these patients had preleukemia and the third had overt acute leukemia may imply that patients with IASA and X chromosome abnormalities have a poor prognosis. Cases of IASA without associated X chromosome abnormalities are known; thus, if an association between IASA and an abnormal X chromosome does exist, most likely it involves only some patients with IASA. 相似文献
43.
Plasticity of representational maps in adult cerebral cortex has been
documented in both sensory and motor cortex, but the anatomical basis for
cortical plasticity remains poorly understood. To investigate horizontal
connectivity in primary motor cortex (M1) as a putative anatomical
substrate for short-term, functional plasticity of adult motor cortical
representations, a combination of electrical stimulation and biocytin
labeling was used to examine pre-existing patterns of intrinsic connections
in adult rat M1 in relationship to the pattern of reorganization of the
motor movement may induced by transection of the contralateral facial
nerve. Two hours after nerve cut, small, circumscribed regions of the
forelimb representation expanded medially into territory previously devoted
to the vibrissae representation. Outside of this novel, expanded forelimb
region, no forelimb movement could be evoked from the former vibrissae
representation at any time over the period of hours tested, thus
representing silent cortex. Injections placed into vibrissae cortex
representing the newly expanded forelimb representation gave rise to
labeled axons and dense terminal fiber labeling which crossed the
forelimb/vibrissae border and extended up to 1.2 mm within the
low-threshold forelimb representation. In contrast, injections placed into
silent vibrissae cortex gave rise to labeled axons and terminal boutons
which remained mostly restricted to the original vibrissae representation,
with only sparse projections that crossed into the low-threshold forelimb
representation. Thus, these results suggest that the extent of short-term,
functional reorganization of M1 induced within the first several hours
following peripheral nerve cut is mediated, and constrained, by an
anatomical framework of pre-existing, horizontal projections which traverse
representation borders.
相似文献
44.
目的快速鉴定血培养中的金黄色葡萄球菌和凝固酶阴性葡萄球菌(CoNS),结合临床快速判定是否为污染菌。方法采用荧光原位杂交法鉴定血培养中的金黄色葡萄球菌和CoNS,杂交结果若为CoNS,根据临床资料进行判断,并与文献推荐的污染判断法进行结果比较。结果探针的特异性经由标准菌株和临床分离菌株证实。金黄色葡萄球菌探针的特异性和敏感性均为100%,GoNS探针的特异性和敏感性分别为100%和95.5%。179株CoNS中117株判断为污染菌,污染率为68%,与文献推荐的污染判断方法一致。结论荧光原位杂交法适用于血培养中的金黄色葡萄球菌和CoNS的快速鉴定,以排除CoNS污染。 相似文献
45.
目的:构建神经原相关的细胞粘附分子(NrCAM)和免疫球蛋白Fc片段融合基因的重组质粒并通过Baculovirus载体转染到昆虫细胞。方法:利用RT-PCR方法从神经母细胞瘤细胞系SK-N-SN获得NrCAM的信号肽区和跨膜区片段并直接克隆到pGEMT载体,经多次酶切、连接、转化、筛选获得NrCAM-Fc的重组副合基因,测序后将此基因通过Baculovirus载体转染至昆虫细胞。结果:多种酶切和测序结果表明NrCAM-Fc的序列与原序列符合率达98%以上,NrCAM与Fc连接处序列保证了Fc的读码框架(ORF)。结论:Baculovirus载体转染效率高,检测方法简便易行。 相似文献
46.
Quality adjusted life years (QALYs) are well recognized as a valid measure for outcomes in cost-effectiveness analyses. However, it is difficult to obtain a summary utility score from health status measure such as the SF-36.
OBJECTIVE: To predict a summary utility score (represented by HUI) from the scores on the SF-36.
METHODS: A structural equation framework was applied to data collected from 1992 to 1995 on the Southern California Kaiser Permanente population (n = 5,794). An instrumental variable (IV) method mitigated the endogeneity in estimating the HUI(MarkII). Socioeconomic and disease variables were used as covariates. A split-sample analysis provided cross-validation.
RESULT: This model predicted 33.68% of the observed variance in HUI index scores with an adjusted R2 of 0.3335. Observed HUI index scores were distributed with a mean of 0.7963 and std. deviation of 0.1796. Parameter estimates of most of the SF-36 components (except General Health & Social Functioning) showed statistical significance at α= 0.05 level. People with high chronic disease scores were found to have low SF-36 scores, and parameter estimates of this covariate were also found statistically significant at α= 0.05 level in all structural equations. However, all the socioeconomic variables showed statistical insignificance. Comparison of "Forecasting" and "Estimation" sub-samples showed satisfactory results during cross-validation.
CONCLUSION: Result of this study provides a quantitative link between two important measures of health status. The present model can be used to estimate overall health utility summary scores from previous studies using the SF-36. 相似文献
OBJECTIVE: To predict a summary utility score (represented by HUI) from the scores on the SF-36.
METHODS: A structural equation framework was applied to data collected from 1992 to 1995 on the Southern California Kaiser Permanente population (n = 5,794). An instrumental variable (IV) method mitigated the endogeneity in estimating the HUI(MarkII). Socioeconomic and disease variables were used as covariates. A split-sample analysis provided cross-validation.
RESULT: This model predicted 33.68% of the observed variance in HUI index scores with an adjusted R
CONCLUSION: Result of this study provides a quantitative link between two important measures of health status. The present model can be used to estimate overall health utility summary scores from previous studies using the SF-36. 相似文献
47.
γ-去氢骆驼蓬碱等咔啉类生物碱的辐射防护作用 总被引:8,自引:0,他引:8
γ- Harmine(Ⅰ),’harmine(Ⅱ )and harmaline(Ⅲ )were isolated from PeganumHarmala L.( Zygophylaceae).Tests were conducted with mice to detect whether γ- harmine( a newcompound), harmine,harmof(Ⅳ)and harmalol(Ⅴ) are effective radioprotective compounds againstγ-ray irradiation, Intraperitoneal injection of the hydrochlorides of the four alkaloids 50~80mg·kg-1×1 in NIH male mice 30~45 minutes before 8.6~9. 7 Gy whole body 60Co irradiationsignificantly increased the survival effects(1. 33~2. 61)and 30-day survivai rate in comparison withcontrol mice.The results indicatethat γ- harmine exhibited relatively good radioprotective effect.γ-harmine is the first alkaloid isolated from a plant having ptotective effects against whole-body lethal irradiation in mice. 相似文献
48.
49.
Reversible oxidant-induced increases in albumin transfer across cultured endothelium: alterations in cell shape and calcium homeostasis 总被引:20,自引:0,他引:20
To determine whether reactive oxygen molecules could directly and reversibly increase the transfer of albumin across an endothelial barrier, we measured albumin transfer across monolayers of endothelium cultured on micropore filters before and after exposure to xanthine and xanthine oxidase. Xanthine and xanthine oxidase increased endothelial albumin transfer in a dose-dependent fashion. Parallel phase contrast and fluorescence microscopy demonstrated retraction of adjacent cells from one another and disruption of the actin filaments. The oxidant- induced increases in albumin transfer and changes in cell shape were reversed by removing xanthine oxidase and then incubating the monolayers for 3 1/2 hours in tissue culture media enriched with fetal bovine serum. However, incubation in tissue culture media without serum resulted in progressive injury and cell death. Hence, the brief exposure to oxidants initiated a progressive injury process that was reversed by incubation in serum. Because intracellular and extracellular calcium are important determinants of cell shape, and because some oxidized membrane lipids act as calcium ionophores, we asked whether oxidants altered endothelial calcium homeostasis. Xanthine-xanthine oxidase increased release of 45Ca++ from preloaded cells. The calcium antagonist lanthanum chloride prevented xanthine- xanthine oxidase increases in endothelial albumin transfer and prevented the changes in cell shape; chelation of extracellular calcium inhibited lysis of endothelium by xanthine-xanthine oxidase; and the calcium ionophore A23187 increased endothelial albumin transfer and mimicked the oxidant-induced changes in cell shape. Lanthanum chloride inhibited these effects of A23187. These data suggest that oxygen radicals can reversibly increase endothelial permeability to macromolecules, that this is associated with reversible changes in endothelial cell shape and actin filaments, and that the changes in cell shape are related to oxidant-induced changes in endothelial calcium homeostasis. 相似文献
50.