首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   241篇
  免费   10篇
  国内免费   4篇
  2022年   3篇
  2021年   3篇
  2020年   2篇
  2019年   2篇
  2018年   5篇
  2017年   3篇
  2016年   9篇
  2015年   11篇
  2014年   18篇
  2013年   9篇
  2012年   5篇
  2011年   8篇
  2010年   10篇
  2009年   8篇
  2008年   6篇
  2007年   22篇
  2006年   5篇
  2005年   11篇
  2004年   5篇
  2003年   7篇
  2002年   9篇
  2001年   8篇
  2000年   3篇
  1999年   4篇
  1998年   10篇
  1997年   1篇
  1996年   2篇
  1995年   2篇
  1994年   3篇
  1993年   3篇
  1992年   7篇
  1991年   5篇
  1990年   4篇
  1989年   3篇
  1988年   7篇
  1987年   3篇
  1986年   4篇
  1985年   8篇
  1984年   1篇
  1983年   4篇
  1982年   1篇
  1980年   1篇
  1979年   2篇
  1978年   4篇
  1973年   2篇
  1972年   1篇
  1966年   1篇
排序方式: 共有255条查询结果,搜索用时 31 毫秒
41.

Background

Loss of arm-hand performance due to a hemiparesis as a result of stroke or cerebral palsy (CP), leads to large problems in daily life of these patients. Assessment of arm-hand performance is important in both clinical practice and research. To gain more insight in e.g. effectiveness of common therapies for different patient populations with similar clinical characteristics, consensus regarding the choice and use of outcome measures is paramount. To guide this choice, an overview of available instruments is necessary. The aim of this systematic review is to identify, evaluate and categorize instruments, reported to be valid and reliable, assessing arm-hand performance at the ICF activity level in patients with stroke or cerebral palsy.

Methods

A systematic literature search was performed to identify articles containing instruments assessing arm-hand skilled performance in patients with stroke or cerebral palsy. Instruments were identified and divided into the categories capacity, perceived performance and actual performance. A second search was performed to obtain information on their content and psychometrics.

Results

Regarding capacity, perceived performance and actual performance, 18, 9 and 3 instruments were included respectively. Only 3 of all included instruments were used and tested in both patient populations. The content of the instruments differed widely regarding the ICF levels measured, assessment of the amount of use versus the quality of use, the inclusion of unimanual and/or bimanual tasks and the inclusion of basic and/or extended tasks.

Conclusions

Although many instruments assess capacity and perceived performance, a dearth exists of instruments assessing actual performance. In addition, instruments appropriate for more than one patient population are sparse. For actual performance, new instruments have to be developed, with specific focus on the usability in different patient populations and the assessment of quality of use as well as amount of use. Also, consensus about the choice and use of instruments within and across populations is needed.  相似文献   
42.
Two approaches to prolong the duration of hydrogen production by immobilized, sulfur-limited Chlamydomonas reinhardtii cells are examined. The results demonstrate that continuous H2 photoproduction can occur for at least 90 days under constant flow of TAP medium containing micromolar sulfate concentrations. Furthermore, it is also possible to prolong the duration of H2 production by cycling immobilized cells between minus and plus sulfate conditions.  相似文献   
43.
This investigation examined the exposure of Egyptian infants to Aflatoxin M1 (AfM1) and of lactating mothers to Aflatoxin B1, using AfM1 in human milk as a biomarker for exposure to AfB1. The presence of ochratoxin A (OA) in human milk was also investigated to determine the levels of infants exposure to OA from human milk. The results indicated that AfM1 was found in 66 (55 %) of 120 human milk samples with a mean of 0.3 ± 0.53 ng/mL (range 0.02 to 2.09 ng/mL). OA was found in 43 (35.8 %) of 120 human milk samples with a mean of 21.1 ± 13.7 ng/mL (range 5.07 to 45.01 ng/mL), which will cause a daily intake of OA from human milk exceeding the suggested tolerable dose of 5 ng/kg-1 of OA body weight. On the other side AfM1 was found in 25 % of blood samples (5 out of 20 samples), at a mean of 1.18 ng/mL, but it was detected only in one urine sample (1 out of 20 samples). OA was detected only in 2 out of 13 blood samples (15.4 %) with an average 3.67 ng/mL. Whereas OA was not detected in all analyzed urine samples.  相似文献   
44.
Physiological, biochemical and histological indices in Clarias gariepinus broodstock, and teratogenic indices in embryos exposed to sublethal concentrations of naphthalene, phenanthrene and pyrene were investigated in 2014 using a static-renewal bioassay protocol. Phenanthrene (1.41 mg l?1) was the most toxic, followed by pyrene (1.53 mg l?1) and naphthalene (7.21 mg l?1), based on 96 h LC50 values. Hepatosomatic indices were significantly higher in naphthalene- and pyrene-treated males compared with solvent controls, whereas fecundity in females was significantly lower by factors of 2.4 (naphthalene), 2.8 (phenanthrene) and 2.4 (pyrene), compared with controls. Catalase levels were lower in female phenanthrene-treated fish compared with controls. Histological alterations observed in PAH-treated fish include oedema, inflammatory cells, epithelial lifting and hyperplasia in the gills, vacuolation, haemosiderin pigments and sinusoidal congestion in the liver, and degenerated zona radiata in the ovary. Teratogenic effects were not observed, as evidenced by the lack of histological alterations in embryos spawned from pre-exposed broodstock. Sex-specific responses and the utility of biomarkers at cellular and individual levels of organisation are therefore demonstrated for holistic evaluations of polycyclic aromatic hydrocarbons in ecotoxicological studies.  相似文献   
45.
Integrin β3 is seen as a key anti‐angiogenic target for cancer treatment due to its expression on neovasculature, but the role it plays in the process is complex; whether it is pro‐ or anti‐angiogenic depends on the context in which it is expressed. To understand precisely β3's role in regulating integrin adhesion complexes in endothelial cells, we characterised, by mass spectrometry, the β3‐dependent adhesome. We show that depletion of β3‐integrin in this cell type leads to changes in microtubule behaviour that control cell migration. β3‐integrin regulates microtubule stability in endothelial cells through Rcc2/Anxa2‐driven control of active Rac1 localisation. Our findings reveal that angiogenic processes, both in vitro and in vivo, are more sensitive to microtubule targeting agents when β3‐integrin levels are reduced.  相似文献   
46.
The pH dependences of activities of homogenous hydrogenases of Thiocapsa roseopersicina and Desulfomicrobium baculatum in the reaction of hydrogen uptake in solution in the presence of benzyl viologen and the pH dependences of catalytic currents of hydrogen oxidation by electrodes on which these hydrogenases were immobilized were compared. Maximal activities of the hydrogenases from T. roseopersicina and D. baculatum in the reaction hydrogen uptake in solution were observed at pH 9.5 and 8.5, respectively. However, the steady-state current caused by catalytic uptake of hydrogen was maximal for the T. roseopersicina hydrogenase-containing electrode at pH 5.5-6.5 under overvoltage of 30-60 mV, whereas for electrodes with D. baculatum hydrogenase it was maximal at pH 6.0-6.5. Analysis of these data suggests that pH-dependent changes in the hydrogenase activities in solution during hydrogen uptake are due not only to the effect of proton concentration on the enzyme conformation or protonation of certain groups of the enzyme active center, but they are rather indicative of changes in free energy of the reaction accompanying changes in pH.  相似文献   
47.
48.

Background  

Cervical-vaginal fluid (CVF) plays an important role in the prevention of gynecological infections, although little is known about the contribution of CVF proteins to the immunity of the lower female genital tract. In order to analyze the protein composition of human CVF, we used CVF samples that are routinely collected during colposcopy, but are usually discarded. Since these samples are available in large quantities we aimed to analyze their usefulness for proteomics experiments. The samples were analyzed using different prefractionation techniques (ultrafiltration and C4(RP)-LC protein separation) followed by C18(RP)-LC peptide separation and identification by MALDI-TOF-TOF mass spectrometry. To determine the reproducibility of this proteomics platform we analyzed three technical replicates. Using spectral counting, protein abundances were estimated in a semiquantitative way. We also compared the results obtained in this study with those from previous studies derived from patients with different physiological conditions in order to determine an overlapping protein set.  相似文献   
49.
Hydrogen uptake in the presence of various terminal electron acceptors was examined in Escherichia coli mutants synthesizing either hydrogenase 1 or hydrogenase 2. Both hydrogenases mediated nitrate-dependent H2 consumption but neither of them was coupled with nitrite. Unlike hydrogenase 2, hydrogenase 1 demonstrated poor activity with electron acceptors of low midpoint redox potential. Oxygen-linked H2 uptake via hydrogenase 1 was observed over a wide range of air concentrations. Hydrogenase 2 catalyzed this reaction only at low air concentrations. Thus, hydrogenase 1 works in cells at higher redox potential, being more tolerant to oxygen than hydrogenase 2.  相似文献   
50.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号