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1.
We examined susceptibility to the murine rotavirus, epizootic diarrhea of infant mice virus (EDIM), in normal suckling and weaned mice and in suckling mice treated with glucocorticoids. Normal mice 1 to 40 days old were inoculated by gastrin intubation with high doses of EDIM and subsequently evaluated for rotavirus infection by solid-phase radioimmunoassay, by electron microscopy of intestinal tissue sections or by both. Radioimmunoassay and electron microscopy showed a concordance of 89.5% in the detection of rotavirus infection. After a period of low susceptibility to EDIM infection during the first 3 days after birth (23%), susceptibility was high for the next 11 days (95%), but decreased abruptly as mice approached weaning (41% on days 15 through 17). Mice 34 days or older did not develop EDIM infection after inoculation, but rotavirus antigen was detected in 12% of uninoculated mothers nursing inoculated litters. Administration of cortisone acetate to 8-day-old mice induced partial intestinal maturation prematurely. At 3 to 6 days after cortisone acetate treatment, susceptibility to EDIM infection decreased to 60% compared with 94% in age-matched controls. Our data suggest (i) that susceptibility of mice to EDIM infection is age dependent, decreasing in concert with intestinal maturation, and (ii) that glucocorticoids, which induce premature partial intestinal maturation, modulate susceptibility of mice to EDIM.  相似文献   
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AIM: To analyze the prognostic value of adipokines in predicting the course, complications and fatal outcome of acute pancreatitis (AP).METHODS: We performed the search of PubMed database and the systemic analysis of the literature for both experimental and human studies on prognostic value of adipokines in AP for period 2002-2012. Only the papers that described the use of adipokines for prediction of severity and/or complications of AP were selected for further analysis. Each article had to contain information about the levels of measured adipokines, diagnosis and verification of AP, to specify presence of pancreatic necrosis, organ dysfunction and/or mortality rates. From the very beginning, study was carried out adhering to the PRISMA checklist and flowchart for systemic reviews. To assess quality of all included human studies, the Quality Assessment of Diagnostic Accuracy Studies tool was used. Because of the high heterogeneity between the studies, it was decided to refrain from the statistical processing or meta-analysis of the available data.RESULTS: Nine human and three experimental studies were included into review. In experimental studies significant differences between leptin concentrations at 24 and 48 h in control, acute edematous and acute necrotizing pancreatitis groups were found (P = 0.027 and P < 0.001). In human studies significant differences between leptin and resitin concentrations in control and acute pancreatitis groups were found. 1-3 d serum adiponectin threshold of 4.5 μg/mL correctly classified the severity of 81% of patients with AP. This threshold yielded a sensitivity of 70%, specificity 85%, positive predictive value 64%, negative predictive value88% (area under curve 0.75). Resistin and visfatin concentrations differ significantly between mild and severe acute pancreatitis groups, they correlate with severity of disease, need for interventions and outcome. Both adipokines are good markers for parapancreatic necrosis and the cut-off values of 11.9 ng/mL and 1.8 ng/mL respectively predict the high ranges of radiological scores. However, the review revealed that all nine human studies with adipokines are very different in terms of methodology and objectives, so it is difficult to generalize their results. It seems that concentrations of the leptin and resistin increases significantly in patients with acute pancreatitis compared with controls. Serum levels of adiponectin, visfatin and especially resitin (positive correlation with Acute Physiology and Chronic Health Evaluation II, Ranson and C-reactive protein) are significantly different in mild acute pancreatitis and severe acute pancreatitis patients, so, they can serve as a markers for the disease severity prediction. Resistin and visfatin can also be used for pancreatic and parapancreatic necrosis prediction, interventions needs and possible, outcome.CONCLUSION: High levels of adipokines could allow for prediction of a severe disease course and outcome even in small pancreatic lesions on computed tomography scans.  相似文献   
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We have investigated the dependence of the static first hyperpolarizability on the bond-length alternation (BLA) parameter. Our analysis indicates that the validity of the first hyperpolarizability/BLA parameter relationship is restricted to the no-field, vacuum, limit, while it successively breaks down along with increasing polarity of a surrounding medium, becoming invalid, for instance, in an aqueous solution. This contention is based on a series of TD-DFT, TD-DFT/PCM and hybrid TD-DFT/MM calculations of the first hyperpolarizability for a set of molecular configurations generated from Car–Parrinello hybrid QM/MM simulations of the stilbazolium merocyanine chromophore in chloroform and water solvents, and on a rationalization by means of the two-state model for the first hyperpolarizability. The BLA dependence of the three parameters entering the two-state model is shown to be qualitatively different in vacuum and in solvents. Particularly, in the vacuum case, the difference between ground and excited state dipole moments goes to zero for a vanishing BLA, which is not true in the presence of an aqueous medium. In the aqueous medium, an opposing behavior of the parameters involved in the two-state model results in an almost constant first hyperpolarizability with varying BLA parameter.  相似文献   
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AIM: To define the probability of foetal and neonatal death (PFND) in Lithuania by means of the Medical Birth registry. METHODS: The Medical Birth registry for the year 2002 (29,619 pregnancies resulting in delivery) was used, covering social, environmental, health behaviour factors, obstetric history, health status of pregnant women, and delivery. RESULTS: A statistically significant model has been obtained in which 12 out of 45 analysed factors were significant for the risk of perinatal mortality (PM). In the case of previous neonatal pathology, e.g. damage to CNS, the risk of PM (OR 5.2; 95% CI = 2.1-13.3) was similar to the reported manual work or harmful working conditions during pregnancy (OR 4.8; 95% CI = 1.9-12.1 and OR 4.5; 95% CI = 1.3-15.2, respectively). The influence of father's alcohol abuse (OR 2.6; 95% CI = 1.4-4.7) was comparable to that of the stillborns or premature deliveries. The combination of several factors increased PFND significantly: maternal smoking during pregnancy and paternal smoking and alcohol abuse raised PFND to 0.03 (OR 6.8), mother's hard manual work in combination with harmful conditions during pregnancy increased OR more than 10 times (PFND 0.32) as compared with the situation when only one of those factors was present. CONCLUSIONS: The influence of social, environmental, and behavioural factors on the risk of PM was comparable to that of some of the complications during a previous pregnancy. The combination of risk factors significantly increased PFND. Using modelling, the individual prognosis may be presented to every pregnant woman at an early stage of pregnancy to potentially decrease the impact of unfavourable risk factors on PM.  相似文献   
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In this work, the suitability of natural raw materials with various modifications of SiO2—granite sawing waste (quartz) and opoka (a mixture of cristobalite, tridymite, quartz, and an amorphous part)—for the 1.13 nm tobermorite and xonotlite synthesis is examined, and their specific surface area, pore diameter and volume, and the predominant pores are determined. Hydrothermal syntheses were carried out at 200 °C for 12 and 72 h from mixtures with a molar ratio of CaO/SiO2 = 1.0. X-ray diffraction analysis, simultaneous thermal analysis, and scanning electronic microscopy were used, which showed that in the lime–calcined opoka mixture the formation of crystalline calcium silicate hydrates takes place much faster than in the lime–granite sawing waste mixture. The high reactivity of amorphous SiO2 results in the rapid formation of 1.13 nm tobermorite and xonotlite (12 h). According to Brunauer, Emmet and Taller (BET) analysis data, this product features a specific surface area of ~68 m2/g, a total pore volume of 245 × 10−3 cm3/g, and has dominating 1–2.5 nm and 5–20 nm diameter pores. This porosity of the material should provide good thermal insulation properties of the products made from it as no air convection occurs in the fine pores.  相似文献   
9.
Gastric cancer (GC) is one of the most common malignancies worldwide and surgery remains the only potentially curative treatment option for it. Although a significant proportion of GC patients are found with distant metastases already at the initial diagnosis. Peritoneal dissemination is the most common site of metastases. Positive peritoneal cytology (Cy1) is associated with poor long-term outcomes; thus, these patients are considered as stage IV even if macroscopic carcinomatosis is absent. Currently, there is no clear evidence for the most optimal treatment for this distinct subpopulation of the stage IV cohort. Available strategies vary from palliative chemotherapy to upfront gastrectomy. This comprehensive review summarized current evidence of different treatment strategies for Cy1 GC including roles of surgery, systemic and intraperitoneal chemotherapy.  相似文献   
10.
Heme oxygenase-1 (HO-1) is believed to represent a key enzyme for the protection of cells against "stress." Its overexpression in different types of human cancers supports the notion that HO-1 provides a growth advantage and contributes to cellular resistance against chemotherapy and radiotherapy. Given the poor survival rates of patients with pancreatic cancer due to its aggressive growth behavior and its exceptional resistance to all known forms of anticancer treatment, we have investigated the expression of HO-1 in human pancreatic cancer cells growth behavior and prognosis. Expression of HO-1 was analyzed in human pancreatic cancer samples in comparison with normal pancreas by quantitative PCR, Western blot, and confocal microscopy. The influence of radiotherapy and chemotherapy on HO-1 expression in pancreatic cancer cell lines was evaluated. Furthermore, HO-1 expression was specifically suppressed by small interfering RNA transfection and subsequently the alterations of growth behavior and resistance to anticancer treatment were tested. Human pancreatic cancer showed a 6-fold and 3.5-fold HO-1 up-regulation in comparison to normal pancreas based on mRNA and protein level, respectively (P < 0.05). Cancer tissues revealed marked HO-1 immunoreactivity in tumor cells and in tumor associated immunocytes. Treatment of the pancreatic cancer cell lines with gemcitabine or radiation strongly induced HO-1 expression. Targeted knockdown of HO-1 expression led to pronounced growth inhibition of the pancreatic cancer cells and made tumor cells significantly more sensitive to radiotherapy and chemotherapy. Therefore, specific inhibition of HO-1 expression may be a new option in pancreatic cancer therapy and may be used as sensitizer to chemotherapy and radiotherapy.  相似文献   
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