全文获取类型
收费全文 | 250篇 |
免费 | 25篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 15篇 |
妇产科学 | 3篇 |
基础医学 | 59篇 |
口腔科学 | 3篇 |
临床医学 | 24篇 |
内科学 | 43篇 |
皮肤病学 | 10篇 |
神经病学 | 25篇 |
特种医学 | 7篇 |
外科学 | 26篇 |
综合类 | 1篇 |
预防医学 | 22篇 |
眼科学 | 1篇 |
药学 | 14篇 |
肿瘤学 | 21篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 2篇 |
2019年 | 7篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 6篇 |
2015年 | 4篇 |
2014年 | 5篇 |
2013年 | 17篇 |
2012年 | 9篇 |
2011年 | 8篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 8篇 |
2007年 | 14篇 |
2006年 | 16篇 |
2005年 | 9篇 |
2004年 | 5篇 |
2003年 | 18篇 |
2002年 | 17篇 |
2001年 | 14篇 |
2000年 | 12篇 |
1999年 | 10篇 |
1998年 | 9篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 6篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1976年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有276条查询结果,搜索用时 10 毫秒
1.
The cell-fusing ability of Newcastle disease virus (NDV) was quantified using flow microfluorometry (FMF). The rate of polykaryocyte formation, fusion dependence on multiplicity of infection, and cell fusion differences for 21 NDV strains were measured using this technique. No correlation was found between the virulence of a virus strain and its cell fusion index calculated from the FMF data. 相似文献
2.
3.
4.
5.
Fang Z Forslund N Takenaga K Lukanidin E Kozlova EN 《Journal of neuroscience research》2006,83(4):619-626
The central nervous system (CNS) is considered a nonpermissive environment for axonal regeneration because of the presence of myelin and associated repulsive molecules. However, neural cells transplanted to the CNS preferably migrate and extend their fibers in white matter areas. We previously showed that white matter astrocytes in vivo express the calcium-binding protein S100A4, which is strongly up-regulated in areas of white matter degeneration. To investigate the role of white matter astrocytes and their specific protein S100A4 in axonal regeneration, we developed white matter astrocyte cultures with strong S100A4 expression and grew dissociated adult dorsal root ganglion (DRG) cells on top of astrocytes for 24 hr. By using small interfering S100A4 RNA, we were able to eliminate S100A4 expression and compare growth of DRG cell neurites on S100A4-silenced and S100A4-expressing astrocytes. In addition, we studied whether extracellular S100A4 has an effect on neurite growth from adult DRG cells cultured on S100A4-expressing white matter astrocytes. Our data show that white matter astrocytes are permissive for neurite growth, although high levels of S100A4 in white matter astrocytes have a negative effect on this growth. Extracellular application of S100A4 induced extensive growth of DRG cell neurites on white matter astrocytes. These findings suggest that white matter astrocytes are able to support axonal regeneration and, furthermore, that administration of extracellular S100A4 provides strong additional support for axonal regeneration. 相似文献
6.
Reliable high risk HPV DNA testing by polymerase chain reaction: an intermethod and intramethod comparison 总被引:7,自引:0,他引:7 下载免费PDF全文
Jacobs MV Snijders PJ Voorhorst FJ Dillner J Forslund O Johansson B von Knebel Doeberitz M Meijer CJ Meyer T Nindl I Pfister H Stockfleth E Strand A Wadell G Walboomers JM 《Journal of clinical pathology》1999,52(7):498-503
BACKGROUND: The development of a reproducible, sensitive, and standardised human papillomavirus (HPV) polymerase chain reaction (PCR) test is required to implement HPV testing in cervical cancer screening programmes and for triaging women with mild to moderate dysplasia. AIMS: To determine the intermethod agreement between different GP5+/6+ and MY09/11 PCR based protocols for the detection and typing of high risk (HR) HPV DNA in cervical smears and to assess the intramethod reproducibility of the GP5+/6+ PCR enzyme immunoassay (EIA) for HR-HPV detection. METHODS: For the intermethod comparison, crude aliquots of 20 well characterised cervical smears comprising five HPV negative samples, and six and nine samples containing single and multiple HPV infections, respectively, were coded and sent from reference laboratory (A) to three other laboratories. One of these (laboratory B) used the GP5+/6+ PCR-EIA and was provided with standard protocols. Another laboratory (C) used GP5+/6+ PCR combined with sequence analysis and type specific PCR, whereas two laboratories (D and E) used MY09/11 PCR followed by restriction fragment length polymorphism (RFLP) analysis for the detection and typing of HR-HPV. The intramethod agreement of GP5+/6+ PCR-EIA was analysed in a subsequent study with four other laboratories (F to I) on crude aliquots of 50 well characterised cervical smears, consisting of 32 HR-HPV positive and 18 HPV negative samples. Standardised protocols, primers, and probes were also provided by the reference laboratory for HR-HPV detection. RESULTS: In the intermethod comparison, pairwise agreement of the different laboratories with reference laboratory A for the detection of HR-HPV varied between 75% and 100% (kappa values: 0.5 to 1). Typing data revealed a broader range in pairwise agreement rates between 32% and 100%. The highest agreement was found between laboratories A and B using standardised protocols and validated reagents. In the intramethod evaluation, pairwise comparison of the laboratories F to I with reference laboratory A revealed excellent agreement rates from 92% to 100% (kappa values: 0.88 to 1.0) with an overall sensitivity of 97.5% (195/200) and specificity of 99.5% (199/200). CONCLUSIONS: The detection of HR-HPV as a group is highly reproducible with GP5+/6+ PCR-EIA provided that standardised protocols and validated reagents are used. 相似文献
7.
8.
Fredrik Ahlsson Barbro Diderholm Uwe Ewald Björn Jonsson Anders Forslund Mats Stridsberg Jan Gustafsson 《European journal of obstetrics, gynecology, and reproductive biology》2013
Objective
The role of adipokines in the regulation of energy substrate production in non-diabetic pregnant women has not been elucidated. We hypothesize that serum concentrations of adiponectin are related to fetal growth via maternal fat mass, insulin resistance and glucose production, and further, that serum levels of leptin are associated with lipolysis and that this also influences fetal growth. Hence, we investigated the relationship between adipokines, energy substrate production, insulin resistance, body composition and fetal weight in non-diabetic pregnant women in late gestation.Study design
Twenty pregnant women with normal glucose tolerance were investigated at 36 weeks of gestation at Uppsala University Hospital. Levels of adipokines were related to rates of glucose production and lipolysis, maternal body composition, insulin resistance, resting energy expenditure and estimated fetal weights. Rates of glucose production and lipolysis were estimated by stable isotope dilution technique.Results
Median (range) rate of glucose production was 805 (653–1337) μmol/min and that of glycerol production, reflecting lipolysis, was 214 (110–576) μmol/min. HOMA insulin resistance averaged 1.5 ± 0.75 and estimated fetal weights ranged between 2670 and 4175 g (−0.2 to 2.7 SDS). Mean concentration of adiponectin was 7.2 ± 2.5 mg/L and median level of leptin was 47.1 (9.9–58.0) μg/L. Adiponectin concentrations (7.2 ± 2.5 mg/L) correlated inversely with maternal fat mass, insulin resistance, glucose production and fetal weight, r = −0.50, p < 0.035, r = −0.77, p < 0.001, r = −0.67, p < 0.002, and r = −0.51, p < 0.032, respectively. Leptin concentrations correlated with maternal fat mass and insulin resistance, r = 0.76, p < 0.001 and r = 0.73, p < 0.001, respectively. There was no correlation between maternal levels of leptin and rate of glucose production or fetal weight. Neither were any correlations found between levels of leptin or adiponectin and maternal lipolysis or resting energy expenditure.Conclusion
The inverse correlations between levels of maternal adiponectin and insulin resistance as well as endogenous glucose production rates indicate that low levels of adiponectin in obese pregnant women may represent one mechanism behind increased fetal size. Maternal levels of leptin are linked to maternal fat mass and its metabolic consequences, but the data indicate that leptin lacks a regulatory role with regard to maternal lipolysis in late pregnancy. 相似文献9.
H Helenius L Laasonen T Forslund B Kock B Kuhlb?ck J Edgren 《Scandinavian journal of urology and nephrology》1983,17(2):213-216
Renal ultrasonic scanning was performed before and after 57 consecutive kidney biopsies in order to assess the value of this method in the diagnosis of complications. One large and six small perirenal haematomas were found, corresponding to an incidence of 13%. This figure is considerably larger than the incidence found with conventional diagnostic methods, but smaller than with computed tomography. One hydronephrosis and a blood clot in the urinary bladder were also diagnosed. No clinically significant complications were missed. We recommend ultrasonography as the first diagnostic procedure when biopsy complications are suspected. 相似文献
10.
Operators' experiences of emergency calls 总被引:1,自引:0,他引:1
In Sweden, the operators at emergency dispatch centres are responsible for allocating resources (e.g. ambulances, fire brigade, police) in response to calls. We analysed situations that the emergency operators experienced as difficult and their reflections on how they managed them. Interviews were conducted with all 16 emergency operators at a centre that serves a population of 275,000 and receives about 700,000 emergency calls annually. A phenomenological-hermeneutic approach was used for the analysis. Situations that operators experienced as difficult were characterized by uncertainty, communication difficulties and insufficient resources. Skills, knowledge and experience were regarded as important in the management of these situations, as were personal qualities such as sensitivity, insight, empathy and intuition. The emergency operators stated that they needed more guidance, feedback and education in their work. This would lead to an increased sense of certainty, which would lead to decreased stress and a better outcome for those in need. 相似文献