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211.
Lukas Mangnus Hanna W. van Steenbergen Elisabet Lindqvist Elisabeth Brouwer Monique Reijnierse Tom WJ Huizinga Peter K. Gregersen Ewa Berglin Solbritt Rantap??-Dahlqvist Désirée van der Heijde Annette HM van der Helm-van Mil 《Arthritis research & therapy》2015,17(1)
IntroductionThe western population is ageing. It is unknown whether age at diagnosis affects the severity of Rheumatoid Arthritis (RA), we therefore performed the present study.Method1,875 RA-patients (7,219 radiographs) included in five European and North-American cohorts (Leiden-EAC, Wichita, Umeå, Groningen and Lund) were studied on associations between age at diagnosis and joint damage severity. In 698 Leiden RA-patients with 7-years follow-up it was explored if symptom duration, anti-citrullinated-peptide-antibodies (ACPA), swollen joint count (SJC) and C-reactive-protein (CRP) mediated the association of age with joint damage. Fifty-six other RA-patients of the EAC-cohort underwent baseline MRIs of wrist, MCP and MTP-joints; MRI-inflammation (RAMRIS-synovitis plus bone marrow edema) was also evaluated in mediation analyses. Linear regression and multivariate normal regression models were used.ResultsAnalysis on the five cohorts and the Leiden-EAC separately revealed 1.026-fold and 1.034-fold increase of radiographic joint damage per year increase in age (β=1.026, 1.034, both p<0.001); this effect was present at baseline and persisted over time. Age correlated stronger with baseline erosion-scores compared to joint space narrowing (JSN)-scores (r=0.38 versus 0.29). Symptom duration, ACPA, SJC and CRP did not mediate the association of age with joint damage severity. Age was significantly associated with the MRI-inflammation-score after adjusting for CRP and SJC (β=1.018, p=0.027). The association of age with joint damage (β=1.032, p=0.004) decreased after also including the MRI-inflammation-score (β=1.025, p=0.021), suggesting partial mediation.ConclusionRA-patients presenting at higher age have more severe joint damage; this might be partially explained by more severe MRI-detected inflammation at higher age.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0740-0) contains supplementary material, which is available to authorized users. 相似文献212.
Margaret M. Demment Karen Peters J. Andrew Dykens Ann Dozier Haq Nawaz Scott McIntosh Jennifer S. Smith Angela Sy Tracy Irwin Thomas T. Fogg Mahmooda Khaliq Rachel Blumenfeld Mehran Massoudi Timothy De Ver Dye 《PloS one》2015,10(9)
Background
Breast and cervical cancers have emerged as major global health challenges and disproportionately lead to excess morbidity and mortality in low- and middle-income countries (LMICs) when compared to high-income countries. The objective of this paper was to highlight key findings, recommendations, and gaps in research and practice identified through a scoping study of recent reviews in breast and cervical cancer in LMICs.Methods
We conducted a scoping study based on the six-stage framework of Arskey and O’Malley. We searched PubMed, Cochrane Reviews, and CINAHL with the following inclusion criteria: 1) published between 2005-February 2015, 2) focused on breast or cervical cancer 3) focused on LMIC, 4) review article, and 5) published in English.Results
Through our systematic search, 63 out of the 94 identified cervical cancer reviews met our selection criteria and 36 of the 54 in breast cancer. Cervical cancer reviews were more likely to focus upon prevention and screening, while breast cancer reviews were more likely to focus upon treatment and survivorship. Few of the breast cancer reviews referenced research and data from LMICs themselves; cervical cancer reviews were more likely to do so. Most reviews did not include elements of the PRISMA checklist.Conclusion
Overall, a limited evidence base supports breast and cervical cancer control in LMICs. Further breast and cervical cancer prevention and control studies are necessary in LMICs. 相似文献213.
Silencing a key gene of the common symbiosis pathway in Nicotiana attenuata specifically impairs arbuscular mycorrhizal infection without influencing the root‐associated microbiome or plant growth 下载免费PDF全文
Karin Groten Ali Nawaz Nam H. T. Nguyen Rakesh Santhanam Ian T. Baldwin 《Plant, cell & environment》2015,38(11):2398-2416
While the biochemical function of calcium and calmodulin‐dependent protein kinase (CCaMK) is well studied, and plants impaired in the expression of CCaMK are known not to be infected by arbuscular mycorrhizal fungi (AMF) in glasshouse studies, the whole‐plant and ecological consequences of CCaMK silencing are not well understood. Here we show that three independently transformed lines of Nicotiana attenuata plants silenced in CCaMK (irCCaMK) are neither infected by Rhizophagus irregularis in the glasshouse nor by native fungal inoculum in the field. The overall fungal community of field‐grown roots did not differ significantly among empty vector (EV) and the transgenic lines, and the bacterial communities only showed minor differences, as revealed by the alpha‐diversity parameters of bacterial OTUs, which were higher in EV plants compared with two of the three transformed lines, while beta‐diversity parameters did not differ. Furthermore, growth and fitness parameters were similar in the glasshouse and field. Herbivory‐inducible and basal levels of salicylic acid, jasmonic acid and abscisic acid did not differ among the genotypes, suggesting that activation of the classical defence pathways are not affected by CCaMK silencing. Based on these results, we conclude that silencing of CCaMK has few, if any, non‐target effects. 相似文献
214.
Shahzad Khurram Tahir M. B. Ashraf M. Nawaz Tasmia Khalid N. R. Kabli Mohammad Reda 《Plasmonics (Norwell, Mass.)》2020,15(4):1205-1212
Plasmonics - A highly efficient, visible-light-driven and hybrid-activated carbon-doped pure tungsten trioxide (WO3) composite photocatalyst, with greatest stability has been synthesized by using... 相似文献
215.
Salt-bridges (sb) play an important role in the folding and stability of proteins. This is deduced from the evaluation of net energy in the microenvironments (ME, residues that are 4 Å away from positive and negative partners of salt-bridge and interact with them). MEs act as a determinant of net-energy due to the intrinsic features in the sequence. The stability of extremophilic proteins is due to the presence of favorable residues at the ME without any unfavorable residues. We studied a dataset of four structures from the protein data bank (PDB) and a homology model (1HM5) to gain insights on this issue. Data shows that the presence of isolated charges and polar residues in the core of extremophilic proteins helps in the formation of stable salt-bridges with reduced desolvation. Thus, site-specific mutations with favorable residues at the ME will help to develop thermo stable proteins with strong salt bridges. 相似文献
216.
Nosheen Mirza Arshid Pervez Qaisar Mahmood Mohammad Maroof Shah Mustafa Nawaz Shafqat 《Ecological Engineering》2011,37(12):1949-1956
The possible arsenic tolerance mechanisms were explored in Arundo donax L. under various supplied arsenic concentrations. The treatments included control (no metal) and five doses of arsenic trioxide i.e., 0, 50, 100, 300, 600 and 1000 μg L−1 As to A. donax. The phytoextraction ability of A. donax L. plants was assessed using both the translocation and bioaccumulation factors. The transpirates were collected to analyze the arsenic concentration volatilized along-with study of anatomical characteristics of the plant parts. In general, the arsenite and arsenate accumulation linearly increased in roots, shoot and leaves with the increasing supplied arsenic levels i.e., from 2.348, 2.775 and 3.25 μg g−1 at 50 μg L−1 to 50, 53.125 and 64.25 μg g−1 arsenite, at 1000 μg L−1, from 4.075, 5.425 and 13.56 μg g−1 at 50 μg L−1 to 71, 62.02 and 436.219 μg g−1 arsenate at 1000 μg L−1, respectively. The order of arsenic accumulation in A. donax L. was: solution As(III) < Root As(III) < Shoot As(III) < Leaf As(III) < Solution As(V) < Root As(V) < Shoot As(V) < Leaf As(V). The range of arsenic volatilization by A. donax L. was 7.2–22% at higher supplied arsenic (300–1000 μg L−1). Volatilization was an important mechanism to avoid toxic effects of arsenic by A. donax L. in addition to bioaccumulation. 相似文献
217.
Yi-Shiuan Lin Arthur Y Shaw Shi-Gang Wang Chia-Chen Hsu I-Wen Teng Min-Jen Tseng Tim HM Huang Ching-Shih Chen Yu-Wei Leu Shu-Huei Hsiao 《Journal of biomedical science》2011,18(1):1-8
Background
The extracellular calcium-sensing receptor (CaSR) belongs to family C of the G protein coupled receptors. Whether the CaSR is expressed in the pulmonary artery (PA) is unknown.Methods
The expression and distribution of CaSR were detected by RT-PCR, Western blotting and immunofluorescence. PA tension was detected by the pulmonary arterial ring technique, and the intracellular calcium concentration ([Ca2+]i) was detected by a laser-scanning confocal microscope.Results
The expressions of CaSR mRNA and protein were found in both rat pulmonary artery smooth muscle cells (PASMCs) and PAs. Increased levels of [Ca2+]o (extracellular calcium concentration) or Gd3+ (an agonist of CaSR) induced an increase of [Ca2+]i and PAs constriction in a concentration-dependent manner. In addition, the above-mentioned effects of Ca2+ and Gd3+ were inhibited by U73122 (specific inhibitor of PLC), 2-APB (specific antagonist of IP3 receptor), and thapsigargin (blocker of sarcoplasmic reticulum calcium ATPase).Conclusions
CaSR is expressed in rat PASMCs, and is involved in regulation of PA tension by increasing [Ca2+]i through G-PLC-IP3 pathway. 相似文献218.
219.
Gastroenteritis is a common illness causing considerable morbidity and mortality worldwide. Despite improvements in detection methods, a significant diagnostic gap still remains. Human bocavirus (HBoV)s, which are associated with respiratory infections, have also frequently been detected in stool samples in cases of gastroenteritis, and a tentative association between HBoVs, and in particular type-2 HBoVs, and gastroenteritis has previously been made. The aim of this study was to determine the role of HBoVs in gastroenteritis, using archived DNA samples from the case-control Infectious Intestinal Disease Study (IID). DNA extracted from stool samples from 2,256 cases and 2,124 controls were tested for the presence of HBoV DNA. All samples were screened in a real time PCR pan-HBoV assay, and positive samples were then tested in genotype 1 to 3-specific assays. HBoV was detected in 7.4% but no significantly different prevalence was observed between cases and controls. In the genotype-specific assays 106 of the 324 HBoV-positive samples were genotyped, with HBoV-1 predominantly found in controls whilst HBoV-2 was more frequently associated with cases of gastroenteritis (p<0.01). A significant proportion of HBoV positives could not be typed using the type specific assays, 67% of the total positives, and this was most likely due to low viral loads being present in the samples. However, the distribution of the untyped HBoV strains was no different between cases and controls. In conclusion, HBoVs, including HBoV-2 do not appear to be a significant cause of gastroenteritis in the UK population. 相似文献
220.