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101.
Aim. Pulmonary complications are known to occur in over half the patients exposed to sulphur mustard. Many studies have focused on the clinical complications, often ignoring the pathogenesis of sulphur mustard. Also, the reasons for the variable severity of lung injuries caused by sulphur mustard are unclear. Hence, the current study was performed to evaluate the correlation between superoxide dismutase (SOD) and catalase (CAT) activity and pulmonary function in patients exposed to sulphur mustard. Methods. Our study was a comparative cross-sectional survey. Two hundred and fifty incident survivors were selected from the Sardasht population who were exposed to sulphur mustard in 1987. A control group from non-exposed civilians was also selected. We used a pulmonary function test, and SOD and CAT activity was measured in these groups. Results. The mean SOD activity in the healthy control group (70.5±10.8 U ml?1) was higher than in the moderate-to-severe group (67.0±6.1 U ml?1) (p <0.001, one-tail ANOVA, least significant difference (LSD) post hoc). The mean activity in the mild group (72.5±6.9 U ml?1) was no higher than in the healthy control group (70.5±10.8 U ml?1) (p=0.095 one-tail ANOVA, LSD post hoc). The mean CAT activity in the healthy control group (4.9±1.5 U ml?1) was lower than in the moderate-to-severe group (8.0±1.8 U ml?1) (p <0.001, one-tail ANOVA, LSD post hoc) and in the mild group (7.5±1.5 U ml?1) (p=0.012 one-tail ANOVA, LSD post hoc). Conclusion. According to our findings, it is reasonable to hypothesize that re-establishment of the activation–inactivation or oxidant–antioxidant balance in favour of the activation and antioxidant balances would be useful as a therapeutic strategy to suppress pathological mechanisms underlying lung injuries. 相似文献
102.
103.
Roland F Hoffmann Sina Zarrintan Simone M Brandenburg Arjan Kol Harold G de Bruin Shabnam Jafari Freark Dijk Dharamdajal Kalicharan Marco Kelders Harry R Gosker Nick HT ten Hacken Johannes J van der Want Antoon JM van Oosterhout Irene H Heijink 《Respiratory research》2013,14(1):97
Background
Cigarette smoking is the major risk factor for COPD, leading to chronic airway inflammation. We hypothesized that cigarette smoke induces structural and functional changes of airway epithelial mitochondria, with important implications for lung inflammation and COPD pathogenesis.Methods
We studied changes in mitochondrial morphology and in expression of markers for mitochondrial capacity, damage/biogenesis and fission/fusion in the human bronchial epithelial cell line BEAS-2B upon 6-months from ex-smoking COPD GOLD stage IV patients to age-matched smoking and never-smoking controls.Results
We observed that long-term CSE exposure induces robust changes in mitochondrial structure, including fragmentation, branching and quantity of cristae. The majority of these changes were persistent upon CSE depletion. Furthermore, long-term CSE exposure significantly increased the expression of specific fission/fusion markers (Fis1, Mfn1, Mfn2, Drp1 and Opa1), oxidative phosphorylation (OXPHOS) proteins (Complex II, III and V), and oxidative stress (Mn-SOD) markers. These changes were accompanied by increased levels of the pro-inflammatory mediators IL-6, IL-8, and IL-1β. Importantly, COPD primary bronchial epithelial cells (PBECs) displayed similar changes in mitochondrial morphology as observed in long-term CSE-exposure BEAS-2B cells. Moreover, expression of specific OXPHOS proteins was higher in PBECs from COPD patients than control smokers, as was the expression of mitochondrial stress marker PINK1.Conclusion
The observed mitochondrial changes in COPD epithelium are potentially the consequence of long-term exposure to cigarette smoke, leading to impaired mitochondrial function and may play a role in the pathogenesis of COPD. 相似文献104.
W. Edwin Harris Selvino R. de Kort Caroline M. Bettridge Joana Borges Bradley Cain Hamadi I. Dulle Robert Fyumagwa Donatua Gadiye Martin Jones Ladislaus Kahana Julius Kibebe Jafari R. Kideghesho Fidelcastor F. Kimario Alex Kisingo Francis Makari Emmanuel Martin Andimile Martin Masuruli B. Masuruli Kokel Melubo Hannah L. Mossman Linus Munishi Reginald Mwaya Robert Nasi Oliver Nyakunga Elizabeth Price Rehema A. Shoo Emily F. Strange Elias Symeonakis John E. Fa 《African Journal of Ecology》2021,59(1):326-331
105.
Ghaffari Maedeh Kalantar Seyed Mehdi Hemati Mahdie Dehghani Firoozabadi Ali Asri Amir Shams Ali Jafari Ghalekohneh Sina Haghiralsadat Fateme 《Biotechnology letters》2021,43(5):981-994
Biotechnology Letters - Tumor suppressor miRNAs, miR-15a and miR-16–1, with high-specificity and oncogenic targeting of Bcl-2, can target tumor tissues. Disadvantages of the clinical... 相似文献
106.
Rafiei F. Niknam N. Shiran B. Kohpayegani J. A. Jafari P. 《Molecular biology reports》2021,48(2):1567-1578
Molecular Biology Reports - Spinach is salt-tolerant leafy vegetable stemmed from central Asia. It has been well adapted to different climates of Iran. We aimed to study genetic diversity between... 相似文献
107.
Eva Absmeier Karen Vester Tahereh Ghane Dmitry Burakovskiy Pohl Milon Petra Imhof Marina V. Rodnina Karine F. Santos Markus C. Wahl 《The Journal of biological chemistry》2021,297(1)
Brr2 is an essential Ski2-like RNA helicase that exhibits a unique structure among the spliceosomal helicases. Brr2 harbors a catalytically active N-terminal helicase cassette and a structurally similar but enzymatically inactive C-terminal helicase cassette connected by a linker region. Both cassettes contain a nucleotide-binding pocket, but it is unclear whether nucleotide binding in these two pockets is related. Here we use biophysical and computational methods to delineate the functional connectivity between the cassettes and determine whether occupancy of one nucleotide-binding site may influence nucleotide binding at the other cassette. Our results show that Brr2 exhibits high specificity for adenine nucleotides, with both cassettes binding ADP tighter than ATP. Adenine nucleotide affinity for the inactive C-terminal cassette is more than two orders of magnitude higher than that of the active N-terminal cassette, as determined by slow nucleotide release. Mutations at the intercassette surfaces and in the connecting linker diminish the affinity of adenine nucleotides for both cassettes. Moreover, we found that abrogation of nucleotide binding at the C-terminal cassette reduces nucleotide binding at the N-terminal cassette 70 Å away. Molecular dynamics simulations identified structural communication lines that likely mediate these long-range allosteric effects, predominantly across the intercassette interface. Together, our results reveal intricate networks of intramolecular interactions in the complex Brr2 RNA helicase, which fine-tune its nucleotide affinities and which could be exploited to regulate enzymatic activity during splicing. 相似文献
108.
109.
Background
Intimate partner violence against women (IPVAW) is a serious and widespread problem worldwide. Much of the research on IPVAW focused on individual-level factors and attention has been paid to the contextual factors. The aim of this study was to develop and test a model of individual- and community-level factors associated with IPVAW.Methods and Findings
We conducted a (multivariate) multilevel structural equation analysis on 8731 couples nested within 883 communities in Nigerian Demographic and Health Survey 2008. Variables included in the model were derived from respondents'' answers to the experience of IPVAW, attitudes towards wife beating and witnessing physical violence in childhood. We found that women that witnessed physical violence were more likely to have tolerant attitudes towards IPVAW and women with tolerant attitudes were more likely to have reported spousal IPVAW abuse. Women with husbands with tolerant attitudes towards IPVAW were more likely to have reported spousal abuse. We found that an increasing proportion of women in the community with tolerant attitudes was significantly positively associated with spousal sexual and emotional abuse, but not significantly associated with spousal physical abuse. In addition, we found that an increasing proportion of men in the community with tolerant attitudes and an increasing proportion of women who had witnessed physical violence in the community was significantly positively associated with spousal physical abuse, but not significantly associated with spousal sexual and emotional abuse. There was a positive correlation between all three types of IPVAW at individual- and community-level.Conclusions
We found that community tolerant attitudes context in which people live is associated with exposure to IPVAW even after taking into account individual tolerant attitudes. Public health interventions designed to reduce IPVAW must address people and the communities in which they live in order to be successful. 相似文献110.