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391.
Growing evidence has shown that nuclear factor-κB (NF-κB) plays a key role in the initiation and progression of systemic lupus erythematosus (SLE) pathogenesis. A common polymorphism (-94 insertion/deletion ATTG, rs28362491) in the promoter region of NFKB1 gene was identified as functional. The -94del ATTG allele exhibited loss of binding to nuclear proteins and resulted in reduced promoter activity. We investigated the association between NFKB1 -94 insertion/deletion ATTG polymorphism and risk of SLE. A total of 224 SLE patients and 256 control subjects were genotyped using a polymerase chain reaction-polyacrylamide gel electrophoresis strategy and DNA sequencing. We found that the ATTG(1)/ATTG(2) genotype was associated with a significantly decreased risk of SLE (odds ratio=0.52, 95% confidence interval: 0.32-0.87, p=0.012). This finding indicates that the -94 insertion/deletion ATTG polymorphism may play pivotal roles in the development of SLE in the Chinese population. Further studies with larger sample size are warranted to confirm this finding, especially in different populations. 相似文献
392.
Yu M Mazor T Huang H Huang HT Kathrein KL Woo AJ Chouinard CR Labadorf A Akie TE Moran TB Xie H Zacharek S Taniuchi I Roeder RG Kim CF Zon LI Fraenkel E Cantor AB 《Molecular cell》2012,45(3):330-343
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393.
Ting Wang Yang Liu Li Sima Liang Shi Zhaoming Wang Chunhui Ni Zhengdong Zhang Meilin Wang 《PloS one》2012,7(11)
Background
The -93G>A (rs1800734) polymorphism located in the promoter of mismatch repair gene, MLH1, has been identified as a low-penetrance variant for cancer risk. Many published studies have evaluated the association between the MLH1 -93G>A polymorphism and colorectal cancer (CRC) risk. However, the results remain conflicting rather than conclusive.Objective
The aim of this study was to assess the association between the MLH1 -93G>A polymorphism and the risk of CRC.Methods
To derive a more precise estimation of the association, a meta-analysis of six studies (17,791 cases and 13,782 controls) was performed. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the strength of the association. Four of these published studies were performed on subjects of known microsatellite instability (MSI) status. An additional analysis including 742 cases and 10,895 controls was used to assess the association between the MLH1 -93G>A polymorphism and the risk of MSI-CRC.Results
The overall results indicated that the variant genotypes were associated with a significantly increased risk of CRC (AG versus GG: OR = 1.06, 95% CI = 1.01–1.11; AA/AG versus GG: OR = 1.06, 95% CI = 1.01–1.11). This increased risk was also found during stratified analysis of MSI status (AA versus GG: OR = 2.52, 95% CI = 1.94–3.28; AG versus GG: OR = 1.29, 95% CI = 1.10–1.52; AA/AG versus GG: OR = 1.45, 95% CI = 1.24–1.68; AA versus AG/GG: OR = 2.29, 95% CI = 1.78–2.96). Egger’s test did not show any evidence of publication bias.Conclusion
Our results suggest that the MLH1 -93G>A polymorphism may contribute to individual susceptibility to CRC and act as a risk factor for MSI-CRC. 相似文献394.
G Cizza S Mistry VT Nguyen F Eskandari P Martinez S Torvik JC Reynolds PW Gold N Sinai G Csako;for the POWER Study Group 《PloS one》2012,7(7):e40894
Background
An inverse relationship between major depressive disorder (MDD) and bone mineral density (BMD) has been suggested, but prospective evaluation in premenopausal women is lacking.Methods
Participants of this prospective study were 21 to 45 year-old premenopausal women with MDD (n = 92) and healthy controls (n = 44). We measured BMD at the anteroposterior lumbar spine, femoral neck, total hip, mid-distal radius, trochanter, and Ward''s triangle, as well as serum intact parathyroid hormone (iPTH), ionized calcium, plasma adrenocorticotropic hormone (ACTH), serum cortisol, and 24-hour urinary-free cortisol levels at 0, 6, 12, 24, and 36 months. 25-hydroxyvitamin D was measured at baseline.Results
At baseline, BMD tended to be lower in women with MDD compared to controls and BMD remained stable over time in both groups. At baseline, 6, 12, and 24 months intact PTH levels were significantly higher in women with MDD vs. controls. At baseline, ionized calcium and 25-hydroxyvitamin D levels were significantly lower in women with MDD compared to controls. At baseline and 12 months, bone-specific alkaline phosphatase, a marker of bone formation, was significantly higher in women with MDD vs. controls. Plasma ACTH was also higher in women with MDD at baseline and 6 months. Serum osteocalcin, urinary N-telopeptide, serum cortisol, and urinary free cortisol levels were not different between the two groups throughout the study.Conclusion
Women with MDD tended to have lower BMD than controls over time. Larger and longer studies are necessary to extend these observations with the possibility of prophylactic therapy for osteoporosis.Trial Registration
ClinicalTrials.gov NCT 00006180相似文献395.
Florian P Macovei A Sima L Nichita N Mattsby-Baltzer I Roseanu A 《Biochimie et biologie cellulaire》2012,90(3):449-455
Different cell types have been reported to internalize lactoferrin (Lf) by specific or nonspecific receptors. Our studies focused on the endocytic pathway of human Lf in macrophage-like THP-1 cells. Lactoferrin was found to be internalized by THP-1 cells differentiated with phorbol myristate acetate. Incubation of cells with chlorpromazine and dansylcadaverine, inhibitors of clathrin-dependent endocytosis, led to a 50% inhibition of Lf internalization compared with untreated cells. Bafilomycin A1 and NH(4)Cl treatment also resulted in 40%-60% inhibition, respectively, suggesting that the internalization of Lf may partly be mediated by acidic endosome-like organelles. Endocytic uptake of Lf was also cholesterol-dependent, as shown by methyl-β-cyclodextrin or nystatin treatment of the cells prior to internalization. Partial colocalization of Lf and EEA-1, a marker specific for early endosomes, could be observed. Colocalization of Lf with a specific endoplasmic reticulum marker was also detected. Our results suggest that Lf is internalized mainly by the clathrin-dependent pathway in THP-1 cells and targets the ER. The physiological consequences of this intracellular trafficking will be the subject of future investigations. 相似文献
396.
The objective of this paper was to study the potential for bioremoval of a textile dye, Reactive Red 198 (RR198), by a fungus
isolated from soil collected from an effluent disposal area near a textile company. The fungus was identified as Aspergillus flavus, and its use as a low-cost live-cell biomass for the biodegradation of RR198 from contaminated water was investigated using
batch studies. The effects of time, dye concentration, and pH as variable factors were examined in the process. Results showed
that bioremoval of RR198 by A. flavus increased to over 84.96% with increasing time until equilibrium was reached after a period of 24 h. A low pH was the most
effective, as were lower levels of dye concentration. The decolorization was determined by the decrease in the absorption
maximums of this dye by UV–visible spectroscopy. A. flavus was shown to be an efficient fungus for removal of RR198 from wastewater. 相似文献
397.
Papaya shoot tip associated endophytic bacteria isolated from in vitro cultures and host-endophyte interaction in vitro and in vivo 总被引:3,自引:0,他引:3
Fourteen distinct bacterial clones were isolated from surface-sterilized shoot tips (approximately 1 cm) of papaya (Carica papaya L. 'Surya') planted on Murashige and Skoog (MS)-based papaya culture medium (23/50 nos.) during the 2-4 week period following in vitro culturing. These isolates were ascribed to six Gram-negative genera, namely Pantoea (P. ananatis), Enterobacter (E. cloacae), Brevundimonas (B. aurantiaca), Sphingomonas, Methylobacterium (M. rhodesianum), and Agrobacterium (A. tumefaciens) or two Gram-positive genera, Microbacterium (M. esteraromaticum) and Bacillus (B. benzoevorans) based on 16S rDNA sequence analysis. Pantoea ananatis was the most frequently isolated organism (70% of the cultures) followed by B. benzoevorans (13%), while others were isolated from single stocks. Bacteria-harboring in vitro cultures often showed a single organism. Pantoea, Enterobacter, and Agrobacterium spp. grew actively on MS-based normal papaya medium, while Microbacterium, Brevundimonas, Bacillus, Sphingomonas, and Methylobacterium spp. failed to grow in the absence of host tissue. Supplying MS medium with tissue extract enhanced the growth of all the organisms in a dose-dependent manner, indicating reliance of the endophyte on its host. Inoculation of papaya seeds with the endophytes (20 h at OD550=0.5) led to delayed germination or slow seedling growth initially. However, the inhibition was overcome by 3 months and the seedlings inoculated with Pantoea, Microbacterium, or Sphingomonas spp. displayed significantly better root and shoot growths. 相似文献
398.
The in vivo rodent micronucleus test is widely used as a genotoxic assay to detect the clastogenic activity of chemicals. In this research the genotoxic effects of herbal drops of garlic and pasipy were evaluated using the micronucleus test. Maximum Tolerated Dose (MTD) was determined by a dose-response test. For each medicine three treatment groups were considered with doses of MTD, 1/2 MTD and 1/4 MTD according to the CSGMT protocol (1995 Japan). Drugs were administered orally to mice (test groups). Mitomicin C was used as a known genotoxic agent in positive control group. The peripheral blood samples before treatment (zero time samples) were considered as negative control. The appearance of a micronucleus is used as an index for genotoxic potential. The results obtained indicated that the herbal drops showed genotoxicity effect and it was dose-dependent compared to the negative control group. This genotoxicity was significant (p < 0.05) but the genotoxic effects of garlic and pasipy were "not significant" compared to the historical negative control group (p > 0.05). Therefore our results if compared to the negative control group is significant and it is worthy of consideration. 相似文献
399.
400.
Ubiquitous presence of fastidious endophytic bacteria in field shoots and index-negative apparently clean shoot-tip cultures of papaya 总被引:5,自引:0,他引:5
This study establishes the widespread prevalence of fastidious or viable but non-culturable endophytic bacteria in field shoots
and in unsuspicious shoot-tip cultures of papaya (Carica papaya L.) against the norm of asepsis in vitro. A total of 150 shoot-tips (approximately 10 mm) were inoculated on MS-based culture
medium after surface sterilization of field-derived axillary shoots of cv. Surya during November or January (100 and 50, respectively)
when 35–50% cultures showed endophytic microbial growth on culture medium. Indexing of apparently clean cultures using bacteriological
media helped in detecting and removing additional 14–17% stocks with covert bacteria during the first two passages. The rest
of the stocks stayed consistently index-negative during the first eight subculture cycles, but appeared positive in PCR-screening
undertaken thereafter employing universal bacterial 16S rRNA gene primers indicating the association of non-cultivable bacteria.
Direct sequencing of the PCR product yielded overlapping nucleotide data signifying mixed template or the presence of diverse
endophytic microorganisms. This was confirmed by light microscopy of tissue sap revealing viable bacteria in considerable
numbers, which were detected under phase contrast or with negative staining. Planting tissue segments or applying homogenate
from these stocks on diverse bacteriological media did not induce the organisms to grow in vitro. The shoot cultures displayed
variation in growth and rooting potential, the onus of such variation was solely attributable to the associated microorganisms.
The findings were confirmed with additional field shoots and fresh in vitro stocks established subsequently. The observations
have implications in micropropagation and all other applications involving plant cell, tissue, organ, and protoplast culture. 相似文献