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排序方式: 共有4128条查询结果,搜索用时 31 毫秒
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《Cytokine》2015,74(2):245-252
BackgroundWe aimed to investigate the use of novel serum biomarkers for predicting the recurrence and survival of patients with hepatitis B virus (HBV)-related early hepatocellular carcinoma (HCC) after hepatic resection or radiofrequency ablation (RFA).MethodsOne hundred and five patients with HBV-related HCC, who fulfilled the Milan criteria without vascular invasion and underwent hepatic resection or RFA, were followed-up for a median duration of 52 months. Pretreatment serum concentrations of 16 cytokines including interleukin-6 (IL-6) were measured by using a Luminex 200 system. The measured serum cytokines and several clinical factors were analyzed retrospectively.ResultsUnivariate analysis showed that patients with lower pretreatment serum levels of IL-10, IL-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α had significantly shorter disease-free survival (DFS) than those with higher levels. Multivariate analysis revealed that a low serum IL-6 level (⩽33.00 pg/mL; hazard ratio [HR] = 5.39; 95% confidence interval [CI] = 1.27–22.93; P = 0.022), low platelet count (<100 × 109/L; HR = 2.23; 95% CI = 1.28–3.89; P = 0.005), and low serum albumin level (⩽3.5 g/L; HR = 2.26; 95% CI = 1.28–3.97; P = 0.005) had a negative prognostic impact on DFS. In the analysis for overall survival, a low serum platelet level (<100 × 109/L; HR = 2.80; 95% CI = 1.31–5.99; P = 0.008) and multiple tumor (⩾2; HR = 4.05; 95% CI = 1.56–10.48; P = 0.004) showed a negative prognostic impact on the overall survival.ConclusionA low serum IL-6 level is, in addition to low platelet count and low serum albumin level, an independent prognostic factor for DFS in patients with HBV-related early HCC who underwent hepatic resection or RFA with curative intention. 相似文献
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Wei Liu Yaoting Sun Weigang Ge Fangfei Zhang Lin Gan Yi Zhu Tiannan Guo Kexin Liu 《Molecular & cellular proteomics : MCP》2022,21(2):100187
Drug resistance is a critical obstacle to effective treatment in patients with chronic myeloid leukemia. To understand the underlying resistance mechanisms in response to imatinib mesylate (IMA) and adriamycin (ADR), the parental K562 cells were treated with low doses of IMA or ADR for 2 months to generate derivative cells with mild, intermediate, and severe resistance to the drugs as defined by their increasing resistance index. PulseDIA-based (DIA [data-independent acquisition]) quantitative proteomics was then employed to reveal the proteome changes in these resistant cells. In total, 7082 proteins from 98,232 peptides were identified and quantified from the dataset using four DIA software tools including OpenSWATH, Spectronaut, DIA-NN, and EncyclopeDIA. Sirtuin signaling pathway was found to be significantly enriched in both ADR-resistant and IMA-resistant K562 cells. In particular, isocitrate dehydrogenase (NADP(+)) 2 was identified as a potential drug target correlated with the drug resistance phenotype, and its inhibition by the antagonist AGI-6780 reversed the acquired resistance in K562 cells to either ADR or IMA. Together, our study has implicated isocitrate dehydrogenase (NADP(+)) 2 as a potential target that can be therapeutically leveraged to alleviate the drug resistance in K562 cells when treated with IMA and ADR. 相似文献
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《Biomarkers》2013,18(2):186-191
Context: Usefulness of circulating Chromogranin A (CgA) for the diagnosis of neuroendocrine tumors (NEN) is controversial. The aim of the present study was to assess the actual role of this marker as diagnostic tool. Methods: Serum blood samples were obtained from 42 subjects affected with NEN, 120 subjects affected with non-endocrine neoplasias (non-NEN) and 100 non-neoplastic subjects affected with benign nodular goitre (NNG). Determination of CgA was performed by means of immunoradiometric assay. Results: The CgA levels among NEN-patients were not significantly different from NNG and non-NEN subjects. The Receiver operating characteristic (ROC) curves analysis failed to identify a feasible cut-off value for the differential diagnosis between NEN and the other conditions. Conclusion: Serum CgA is not helpful for the first-line diagnosis of NEN. 相似文献
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J. A. Halford 《Cytopathology》2002,13(6):364-370
A review of negative split-sample cervical cytology cases revealed five cases reported as chronic follicular cervicitis. These cases showed characteristic morphological features in conventional smears with lymphoid cells, plasma cells and tingible body macrophages smeared across the slides. This contrasts with the presentation of ThinPrep samples (Cytic Corporation, Boxburgh, MA, USA), where cells were observed aggregated in clumps. The different presentation noted in liquid-based samples may require careful microscopic evaluation at high-power magnification. 相似文献
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E. Pfeiler 《Journal of fish biology》2001,59(6):1677-1681
Survival times of metamorphosing leptocephali of the bonefish Albula sp. placed in hypoxic sea water (0·68 mg O2 l-1 ) decreased by about three-fold (from c. 15 to 5 min) over the 10 day metamorphic period. Increased sensitivity to hypoxia coincided with increased larval oxygen demand during metamorphosis. Plots of hypoxic survival time against standard length or wet mass suggested that metamorphosis (phase II of larval development) could be divided into subphases (IIa and IIb). American Public Health Association. 相似文献
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KURT C. VERCAUTEREN MICHAEL J. LAVELLE NATHAN W. SEWARD JUSTIN W. FISCHER GREGORY E. PHILLIPS 《The Journal of wildlife management》2007,71(5):1594-1602
Abstract: Direct and indirect contact between wild and farmed cervids along perimeter fences may play a role in transmission of diseases like chronic wasting disease (CWD), but no studies have quantified such interactions. At 9 high-fenced commercial elk (Cervus elaphus) farms in Colorado, USA, during October 2003 to January 2005, we used animal-activated video to estimate rates of fence-line use by wild cervids, rates of direct contact between farmed and wild cervids, and probability of direct contact when wild cervids were present. We recorded 8-fold-more wild elk per unit time than mule deer (Odocoileus hemionus) at fence lines. Depending on site, we recorded 0.66 to 46.90 wild elk per 1,000 hours of camera monitoring. We documented 77 interactions between wild and farmed elk involving naso-oral contact and no contact between wild mule deer and farmed elk. Rate of direct contact ranged from 0.00 to 1.92 direct contacts per 1,000 hours of camera monitoring among sites. Given recorded presence of wild elk, estimated probability of observing direct contact during a 2-minute video recording ranged from 0.00 to 0.11 among sites. Risk of direct contact was about 3.5 times greater for single woven-wire fence compared with offset electric fence attached to a single woven-wire fence. We observed no direct contact through double woven-wire fences. Because little is currently known about infection rates associated with infection mechanisms, we cannot infer a level of CWD infection risk from our results, but some form of double fencing should reduce potential for direct and indirect transmission of disease into or out of elk farms. 相似文献
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1. When dissolved oxygen levels decline in aquatic systems, prey may be unable to maintain behaviours protecting them from predators. We examined how oxygen availability affected anti‐predator responses in the freshwater clam, Corbicula fluminea. 2. When attacked, bivalves protect their soft tissues by closing their protective valves. This reduces vulnerability to small predators, but ventilation and oxygen uptake are suspended. We found that after a simulated attack, clams under low oxygen conditions reopened their valves sooner than clams under high oxygen conditions, suggesting that hypoxia increases vulnerability to predation. 3. Bivalves may also evade predators through burial into the substratum. Deeper burial confers greater refuge from predators, but increases the costs of ventilation. In a second experiment, we studied how burial depth of C. fluminea is affected by oxygen availability. Additionally, we examined whether clams changed burial depth following a simulated attack by a small predator, and whether this response was affected by oxygen availability. Our results offered partial support for the hypothesis that burial depth is reduced under hypoxic conditions, but the simulated attack did not affect burial depth in any oxygen treatments. 相似文献
10.
Etiolated bean plants were grown in intermittent light with dark intervals of shorter or longer duration, to modulate the rate of chlorophyll accumulation, relative to that of the other thylakoid components formed. We thus produced conditions under which chlorophyll becomes more or less a limiting factor. We then tested whether LHC complexes can be incorporated in the thylakoid. It was found that an equal amount of chlorophyll, formed under the same total irradiation received, may be used for the stabilization of few and large-in-size PS units containing LHC components (short dark-interval intermittent light), or for the stabilization of many and small-in-size PS units with no LHC components (long dark-interval intermittent light). The size of the PS units diminishes as the dark-interval duration is increased, with no further change after 98 minutes. The PSII/cytf ratio remains constant throughout development in intermittent light and equal to that of mature chloroplasts (PSII/cytf = 1) except in the case of very long dark-interval regimes, where about half PSII units per cytf are present. The PSII/PSI ratio was found to be correlated with the PSII unit size (the larger the size, the lower the ratio). The number of PSI units operating on the same electron transfer chain varied depending on the size of the PSII unit (the larger the PSII unit size, the more the PSI units per chain). The results suggest that it is not the chlorophyll content per se which regulates the stabilization of LHC in developing thylakoids and consequently the size of the PS units, but rather the rate by which it is accumulated, relative to that of the other thylakoid components.Abbreviations Chl
Chlorophyll
- CL
Continuous light
- CPa
the reaction center complex of PSII
- CPI
the reaction center complex of PSI
- CPIa
Chlorophyll protein complex containing the CPI and the light harvesting complex of PSI
- fr w
fresh weight
- LDC
Light dark cycles
- LHC-I
Light-harvesting complex of PSI
- LHC-II
Light harvesting complex of PSII
- PS
photosystem
- PSI
photosystem I
- PSII
photosystem II 相似文献