全文获取类型
收费全文 | 348篇 |
免费 | 26篇 |
出版年
2021年 | 4篇 |
2019年 | 3篇 |
2018年 | 4篇 |
2016年 | 7篇 |
2015年 | 9篇 |
2014年 | 10篇 |
2013年 | 13篇 |
2012年 | 23篇 |
2011年 | 17篇 |
2010年 | 9篇 |
2009年 | 16篇 |
2008年 | 18篇 |
2007年 | 14篇 |
2006年 | 19篇 |
2005年 | 22篇 |
2004年 | 21篇 |
2003年 | 18篇 |
2002年 | 15篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 8篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 9篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 6篇 |
1988年 | 8篇 |
1987年 | 2篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 10篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1976年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 4篇 |
1970年 | 4篇 |
1968年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有374条查询结果,搜索用时 15 毫秒
51.
Yvonne Lundberg Giwercman Andrej Nikoshkov Kristina Lindsten Birgitta Byström Å. Pousette Alexander V. Chibalin Sivonne Arvidsson Anatoly Tiulpakov Tatiana V. Semitcheva Valentina Peterkova Kerstin Hagenfeldt E. Martin Ritzén A. Wedell 《Human genetics》1998,103(4):529-431
Five mutations in the ligand-binding domain of the androgen receptor gene were identified in patients with complete (A765T,
C784Y, R831X and M895T) or partial (R840G) androgen insensitivity. A765T and R831X have been reported previously whereas the
other three mutations are novel. Receptors carrying these mutations were transiently expressed in COS-1 cells, and androgen
binding and capacity to transactivate an androgen-responsive reporter gene were assayed. C784Y led to abolished androgen
binding and transactivating capacity, R840G and M895T showed reduced specific binding and partial transactivation. The in
vitro functions of the R840G and M895T mutants were improved with supraphysiological concentrations of steroid.
Received: 10 June 1998 / Accepted: 10 September 1998 相似文献
52.
53.
Melican K Boekel J Månsson LE Sandoval RM Tanner GA Källskog O Palm F Molitoris BA Richter-Dahlfors A 《Cellular microbiology》2008,10(10):1987-1998
Ascending urinary tract infections can cause extensive damage to kidney structure and function. We have used a number of advanced techniques including multiphoton microscopy to investigate the crucial early phases of uropathogenic Escherichia coli induced pyelonephritis within a living animal. Our results reveal a previously undescribed innate vascular response to mucosal infection, allowing isolation and eradication of the pathogen. The extremely rapid host response to mucosal infection was highlighted by the triggering of a cascade of events within 3-4 h. Epithelial signalling produced an increase in cellular O(2) consumption and affected microvascular flow by clotting, causing localized ischaemia. Subsequent ischaemic damage affected pathophysiology with actin re-arrangement and epithelial sloughing leading to paracellular bacterial movement. A denuded tubular basement membrane is shown to hinder immediate dissemination of bacteria, giving the host time to isolate the infection by clotting. Suppression of clotting by heparin treatment caused fatal urosepsis. Clinically these findings may be relevant in antibiotics delivery in pyelonephritis patients and to the use of anticoagulants in sepsis. 相似文献
54.
Johanna Thelaus Agneta Andersson Peter Mathisen Anna-Lena Forslund Laila Noppa & Mats Forsman 《FEMS microbiology ecology》2009,67(1):69-80
The natural reservoir of Francisella tularensis , the causative agent of tularaemia, is yet to be identified. We investigated the possibility that Francisella persists in natural aquatic ecosystems between outbreaks. It was hypothesized that nutrient-rich environments, with strong protozoan predation, favour the occurrence of the tularaemia bacterium. To investigate the differences in adaptation to aquatic environments of the species and subspecies of Francisella , we screened 23 strains for their ability to survive grazing by the ciliate Tetrahymena pyriformis . All the Francisella strains tested were consumed at a low rate, although significant differences between subspecies were found. The survival and virulence of gfp -labelled F. tularensis ssp. holarctica were then studied in a microcosm experiment using natural lake water, with varying food web complexities and nutrient availabilities. High nutrient conditions in combination with high abundances of nanoflagellates were found to favour F. tularensis ssp. holarctica . The bacterium was observed both free-living and within the cells of a nanoflagellate. Francisella tularensis entered a viable but nonculturable state during the microcosm experiment. When studied over a longer period of time, F. tularensis ssp. holarctica survived in the lake water, but loss of virulence was not prevented by either high nutrient availability or the presence of predators. 相似文献
55.
Robotics of human movements 总被引:1,自引:0,他引:1
Patrick van der Smagt Markus Grebenstein Holger Urbanek Nadine Fligge Michael Strohmayr Georg Stillfried Jonathon Parrish Agneta Gustus 《Journal of Physiology》2009,103(3-5):119
The construction of robotic systems that can move the way humans do, with respect to agility, stability and precision, is a necessary prerequisite for the successful integration of robotic systems in human environments. We explain human-centered views on robotics, based on the three basic ingredients (1) actuation; (2) sensing; and (3) control, and formulate detailed examples thereof. 相似文献
56.
Marie Jansson Mörk Ulf Emanuelson Ann Lindberg Ivar Vågsholm Agneta Egenvall 《Acta veterinaria Scandinavica》2009,51(1):34
Background
Research has indicated that a number of different factors affect whether an animal receives treatment or not when diseased. The aim of this paper was to evaluate if herd or individual animal characteristics influence whether cattle receives veterinary treatment for disease, and thereby also introduce misclassification in the disease recording system. 相似文献57.
Agneta L. Sunehag Chiara Dalla Man Gianna Toffolo Morey W. Haymond Dennis M. Bier Claudio Cobelli 《Obesity (Silver Spring, Md.)》2009,17(2):233-239
Given the increase in the incidence of insulin resistance, obesity, and type 2 diabetes in children and adolescents, it would be of paramount importance to assess quantitative indices of insulin secretion and action during a physiological perturbation, such as a meal or an oral glucose‐tolerance test (OGTT). A minimal model method is proposed to measure quantitative indices of insulin secretion and action in adolescents from an oral test. A 7 h, 21‐sample OGTT was performed in 11 adolescents. The C‐peptide minimal model was identified on C‐peptide and glucose data to quantify indices of β‐cell function: static φs and dynamic φd responsivity to glucose from which total responsivity φ was also measured. The glucose minimal model was identified on glucose and insulin data to estimate insulin sensitivity, SI, which was compared to a reference measure, SIref, provided by a tracer method. Disposition indices, which adjust insulin secretion for insulin action, were then calculated. Indices of β‐cell function were φs = 51.35 ± 8.89 × 10?9min?1, φd = 1,392 ± 258 × 10?9, and φ = 82.09 ± 17.70 × 10?9min?1. Insulin sensitivity was SI = 14.19 ± 2.73 × 10?4, not significantly different from SIref = 14.96 ± 3.04 × 10?4 dl/kg·min per µU/ml, and well correlated: r = 0.98, P < 0.0001, thus indicating that SI can be accurately measured from an oral test. Disposition indices were DIs = 1,040 ± 201 × 10?14 dl/kg/min2 per pmol/l, DId = 33,178 ± 10,720 × 10?14 dl/kg/min per pmol/l, DI = 1,844 ± 522 × 10?14 dl/kg/min2 per pmol/l. Virtually the same minimal model assessment was obtained with a reduced 3 h, 9‐sample protocol. OGTT interpreted with C‐peptide and glucose minimal model has the potential to provide novel insight regarding the regulation of glucose metabolism in adolescents, and to evaluate the effect of obesity and interventions such as diet and exercise. 相似文献
58.
59.
Gert‐Jan van der Heijden Zhiyue J. Wang Zili D. Chu Pieter J.J. Sauer Morey W. Haymond Luisa M. Rodriguez Agneta L. Sunehag 《Obesity (Silver Spring, Md.)》2010,18(2):384-390
The rise in obesity‐related morbidity in children and adolescents requires urgent prevention and treatment strategies. Currently, only limited data are available on the effects of exercise programs on insulin resistance, and visceral, hepatic, and intramyocellular fat accumulation. We hypothesized that a 12‐week controlled aerobic exercise program without weight loss reduces visceral, hepatic, and intramyocellular fat content and decreases insulin resistance in sedentary Hispanic adolescents. Twenty‐nine postpubertal (Tanner stage IV and V), Hispanic adolescents, 15 obese (7 boys, 8 girls; 15.6 ± 0.4 years; 33.7 ± 1.1 kg/m2; 38.3 ± 1.5% body fat) and 14 lean (10 boys, 4 girls; 15.1 ± 0.3 years; 20.6 ± 0.8 kg/m2; 18.9 ± 1.5% body fat), completed a 12‐week aerobic exercise program (4 × 30 min/week at ≥70% of peak oxygen consumption (VO2peak)). Measurements of cardiovascular fitness, visceral, hepatic, and intramyocellular fat content (magnetic resonance imaging (MRI)/magnetic resonance spectroscopy (MRS)), and insulin resistance were obtained at baseline and postexercise. In both groups, fitness increased (obese: 13 ± 2%, lean: 16 ± 4%; both P < 0.01). In obese participants, intramyocellular fat remained unchanged, whereas hepatic fat content decreased from 8.9 ± 3.2 to 5.6 ± 1.8%; P < 0.05 and visceral fat content from 54.7 ± 6.0 to 49.6 ± 5.5 cm2; P < 0.05. Insulin resistance decreased indicated by decreased fasting insulin (21.8 ± 2.7 to 18.2 ± 2.4 µU/ml; P < 0.01) and homeostasis model assessment of insulin resistance (HOMAIR) (4.9 ± 0.7 to 4.1 ± 0.6; P < 0.01). The decrease in visceral fat correlated with the decrease in fasting insulin (R2 = 0.40; P < 0.05). No significant changes were observed in any parameter in lean participants except a small increase in lean body mass (LBM). Thus, a controlled aerobic exercise program, without weight loss, reduced hepatic and visceral fat accumulation, and decreased insulin resistance in obese adolescents. 相似文献
60.