全文获取类型
收费全文 | 330篇 |
免费 | 25篇 |
专业分类
355篇 |
出版年
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 5篇 |
2017年 | 4篇 |
2016年 | 9篇 |
2015年 | 6篇 |
2014年 | 6篇 |
2013年 | 10篇 |
2012年 | 18篇 |
2011年 | 21篇 |
2010年 | 18篇 |
2009年 | 6篇 |
2008年 | 12篇 |
2007年 | 18篇 |
2006年 | 9篇 |
2005年 | 15篇 |
2004年 | 15篇 |
2003年 | 12篇 |
2002年 | 13篇 |
2001年 | 3篇 |
2000年 | 10篇 |
1999年 | 5篇 |
1997年 | 7篇 |
1996年 | 9篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1984年 | 5篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 5篇 |
1974年 | 9篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1969年 | 2篇 |
1967年 | 2篇 |
排序方式: 共有355条查询结果,搜索用时 15 毫秒
51.
52.
53.
54.
In this 40th anniversary year of the first IVF live birth, it is pertinent to look at all those teams endeavouring to generate live births from this unique technology and who succeeded within 4 years of the first. There were 9 teams who achieved this and a further 3 who were successful soon after, by the end of 1982. This historical review is compiled by 2 authors who were actively engaged in the field of IVF at the time of the first birth and who have remained active in Reproductive Medicine throughout their professional lives. They bring intimate and relevant knowledge of those pioneer researchers from the early years who can be classified as the "Founding Pioneers" of IVF. 相似文献
55.
John A. Craft Fiona E. Robertson Mary E. McPhail Elaine Brown Ronald M. Stagg 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2001,129(2):115-127
Induction of cytochrome P4501A (CYP1A) in fish is an important biomarker in marine monitoring programmes but a number of factors complicate interpretation of data based on catalytic activity. To provide additional analytical tools, we have cloned and sequenced entire (dab) and partial cDNAs (flounder, turbot, sand eel) from several fish species. A detailed analysis comparing the new sequences to those on the database (13 sequences) is presented and identifies an invariant, teleost-specific sequence (195-IVVSVANVICGMCFGRRYDH-214) which might be the basis for production of a species cross-reactive antibody. Northern and slot blots of fish RNA (sand eel, plaice, turbot, flounder and dab) showed extensive cross-species hybridisation with each of the cDNAs (sand eel, plaice, turbot, flounder and dab). The exception was turbot RNA, which only gave adequate hybridisation when the turbot probe was used. Attempts to normalise the hybridisation data to GAPDH mRNA were not satisfactory since there were significant species differences in expression of this gene and expression was suppressed (20–40%) by β-naphthoflavone treatment. The CYP1A probes indicated induction levels relative to untreated dab of: plaice (five-fold); turbot (12-fold); flounder (12-fold); and dab (10-fold). The study demonstrates the relative ease with which species-specific molecular probes can be generated and used. 相似文献
56.
David Wilkin Frederick Graham Michael Shields Ian Craft 《Prostaglandins & other lipid mediators》1974,6(5):405-411
Induction of labour was performed on 20 patients with favourable induction features by amniotomy and administration of a fixed dose of 0.5 mg of prostaglandin E2 (PGE2) hourly. Effective uterine action resulted in a mean time to delivery of 6 hrs 57 mins in primagravid patients and 4 hrs 40 mins in multigravid subjects. In two patients an intravenous oxytocin infusion was used to assist labour. There were no significant maternal or fetal side effects. 相似文献
57.
Rankin AL Guay H Herber D Bertino SA Duzanski TA Carrier Y Keegan S Senices M Stedman N Ryan M Bloom L Medley Q Collins M Nickerson-Nutter C Craft J Young D Dunussi-Joannopoulos K 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(4):1656-1667
MRL/MpJ-Fas(lpr/lpr)/J (MRL(lpr)) mice develop lupus-like disease manifestations in an IL-21-dependent manner. IL-21 is a pleiotropic cytokine that can influence the activation, differentiation, and expansion of B and T cell effector subsets. Notably, autoreactive CD4(+) T and B cells spontaneously accumulate in MRL(lpr) mice and mediate disease pathogenesis. We sought to identify the particular lymphocyte effector subsets regulated by IL-21 in the context of systemic autoimmunity and, thus, generated MRL(lpr) mice deficient in IL-21R (MRL(lpr).IL-21R(-/-)). Lymphadenopathy and splenomegaly, which are characteristic traits of the MRL(lpr) model were significantly reduced in the absence of IL-21R, suggesting that immune activation was likewise decreased. Indeed, spontaneous germinal center formation and plasma cell accumulation were absent in IL-21R-deficient MRL(lpr) mice. Correspondingly, we observed a significant reduction in autoantibody titers. Activated CD4(+) CD44(+) CD62L(lo) T cells also failed to accumulate, and CD4(+) Th cell differentiation was impaired, as evidenced by a significant reduction in CD4(+) T cells that produced the pronephritogenic cytokine IFN-γ. T extrafollicular helper cells are a recently described subset of activated CD4(+) T cells that function as the primary inducers of autoantibody production in MRL(lpr) mice. Importantly, we demonstrated that T extrafollicular helper cells are dependent on IL-21R for their generation. Together, our data highlighted the novel observation that IL-21 is a critical regulator of multiple pathogenic B and T cell effector subsets in MRL(lpr) mice. 相似文献
58.
Wardell TM Ferguson E Chinnery PF Borthwick GM Taylor RW Jackson G Craft A Lightowlers RN Howell N Turnbull DM 《Mutation research》2003,525(1-2):19-27
Mitochondrial DNA (mtDNA) is the only extrachromosomal DNA in human cells. The mitochondrial genome encodes essential information for the synthesis of the mitochondrial respiratory chain. Inherited defects of this genome are an important cause of human disease. In addition, the mitochondrial genome seems to be particularly prone to DNA damage and acquired mutations may have a role in ageing, cancer and neurodegeneration. We wished to determine if radiotherapy and chemotherapy used in the treatment of cancer could induce changes in the mitochondrial genome. Such changes would be an important genetic marker of DNA damage and may explain some of the adverse effects of treatment. We studied samples from patients who had received radiotherapy and chemotherapy for point mutations within the mtDNA control region, and for large-scale deletions. In blood samples from patients, we found a significantly increased number of point mutations compared to the control subjects. In muscle biopsies from 7 of 8 patients whom had received whole body irradiation as well as chemotherapy, the level of a specific mtDNA deletion was significantly greater than in control subjects. Our studies have shown that in patients who have been treated for cancer there is an increased level of mtDNA damage. 相似文献
59.
White MY Cordwell SJ McCarron HC Prasan AM Craft G Hambly BD Jeremy RW 《Proteomics》2005,5(5):1395-1410
Brief periods of myocardial ischemia prior to timely reperfusion result in prolonged, yet reversible, contractile dysfunction of the myocardium, or "myocardial stunning". It has been hypothesized that the delayed recovery of contractile function in stunned myocardium reflects damage to one or a few key sarcomeric proteins. However, damage to such proteins does not explain observed physiological alterations to myocardial oxygen consumption and ATP requirements observed following myocardial stunning, and therefore the impact of alterations to additional functional groups is unresolved. We utilized two-dimensional gel electrophoresis and mass spectrometry to identify changes to the protein profiles in whole cell, cytosolic- and myofilament-enriched subcellular fractions from isolated, perfused rabbit hearts following 15 min or 60 min low-flow (1 mL/min) ischemia. Comparative gel analysis revealed 53 protein spot differences (> 1.5-fold difference in visible abundance) in reperfused myocardium. The majority of changes were observed to proteins from four functional groups: (i) the sarcomere and cytoskeleton, notably myosin light chain-2 and troponin C; (ii) redox regulation, in particular several components of the NADH ubiquinone oxidoreductase complex; (iii) energy metabolism, encompassing creatine kinase; and (iv) the stress response. Protein differences appeared to be the result of isoelectric point shifts most probably resulting from chemical modifications, and molecular mass shifts resulting from proteolytic or physical fragmentation. This is consistent with our hypothesis that the time course for the onset of injury associated with myocardial stunning is too brief to be mediated by large changes to gene/protein expression, but rather that more subtle, rapid and potentially transient changes are occurring to the proteome. The physical manifestation of stunned myocardium is therefore the likely result of the summed functional impairment resulting from these multiple changes, rather than a result of damage to a single key protein. 相似文献