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81.
Summary The anti-inflammatory agent diftalone was administered in the diet to male and female BALB/c mice at 300-, 600-, and 1200-ppm dose levels for 80 weeks, starting at 8 weeks of age. The animals were kept under observation until 126–128 weeks of age, when the experiment was terminated. Diftalone treatment at the highest dose was hepatotoxic and induced hepatocellular tumors in females, angiomas of the liver in males, and angiosarcomas of the liver in male and female mice. The 300- and 600-ppm dose levels were not carcinogenic. The compound was not mutagenic for Salmonella typhimurium.  相似文献   
82.
Background and aimsStudies regarding dietary patterns and cardiometabolic risk markers during pregnancy are scarce. The aim of the present study was to analyse whether different degrees of adherence to the Mediterranean diet (MD) and the MD components were associated with cardiometabolic markers and a clustered cardiometabolic risk during pregnancy.Methods and resultsThis study comprised 119 pregnant women from the GEStation and FITness (GESTAFIT) project. Dietary habits were assessed with a food frequency questionnaire at the 16th and 34th gestational weeks (g.w.). The Mediterranean Diet Score was employed to assess MD adherence. The following cardiometabolic markers were assessed: pre-pregnancy body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose, triglycerides and high-density lipoprotein cholesterol (HDL-C). A greater MD adherence was associated with a better cardiometabolic status in cross-sectional (16th g.w. and 34th g.w.) and prospective analyses (MD adherence at the 16th g.w. and cardiometabolic markers at the 34th g.w.; SBP, DBP and HDL-C; all, p < 0.05). Participants with the highest MD adherence (Tertile 3) had a lower clustered cardiometabolic risk than those with the lowest MD adherence (Tertile 1) at the 16th and 34th g.w. (both, p < 0.05). A higher intake of fruits, vegetables and fish and a lower intake of refined cereals and red meat and subproducts were associated with a lower cardiometabolic risk during pregnancy (all, p < 0.05).ConclusionA higher MD adherence, a greater intake of fruits, vegetables and fish and a lower intake of refined cereals and red meat and subproducts showed a cardioprotective effect throughout gestation.  相似文献   
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84.
The sympathetic outflow appears to be capable of displaying a rhythmicity synchronous with cardiovascular Mayer's waves even after spinal section. To test the hypothesis that spinal sympathetic low frequency (LF) oscillation can be enhanced during sympathetic excitation, we recorded cardiac sympathetic nerve activity (SNA), R-R interval, arterial pressure, and ventilation in 9 unanesthetized decerebrate-vagotomized cats before and after C1 spinal section. LF and high frequency (HF) components were detected in the variability of SNA, R-R interval, and systolic arterial pressure both before and after spinal section. In this latter condition, a significant coherence between LF(SNA) and LF(R-R) was present in 5 animals, whereas HF(SNA) and HF(R-R) were correlated in 4 animals. During an excitatory sympathetic spinal reflex elicited by aortic constriction, the efferent sympathetic firing was markedly enhanced (from 7+/-2 to 33+/-7 spikes/s); concomitantly, the powers of both LF(SNA) and HF(SNA) were also increased. Coherence between LF(SNA) and LF(R-R) became significant in all cases, whereas HF(SNA) and HF(R-R) became correlated in 6 animals. In 3 animals, the reflex sympathetic excitation was no longer elicitable after interrupting a vast contingent of sympathetic afferents by means of thoracic dorsal root section. We report for the first time that LF and HF oscillations are detectable in SNA, R-R interval, and systolic arterial pressure variabilities of decerebrate-vagotomized spinal cats and that an excitatory spinal reflex is capable of increasing the power of both SNA spectral components.  相似文献   
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86.
Haemophilus parasuis is a colonizer of healthy piglets and the etiological agent of Glässer''s disease. Differences in virulence among strains of H. parasuis have been widely observed. In order to explore the host-pathogen interaction, snatch-farrowed colostrum-deprived piglets were intranasally infected with 4 strains of H. parasuis: reference virulent strain Nagasaki, reference nonvirulent strain SW114, field strain IT29205 (from a systemic lesion and virulent in a previous challenge), and field strain F9 (from the nasal cavity of a healthy piglet). At different times after infection, two animals of each group were euthanized and alveolar macrophages were analyzed for the expression of CD163, CD172a, SLA I (swine histocompatibility leukocyte antigen I), SLA II, sialoadhesin (or CD169), and CD14. At 1 day postinfection (dpi), virulent strains induced reduced expression of CD163, SLA II, and CD172a on the surfaces of the macrophages, while nonvirulent strains induced increased expression of CD163, both compared to noninfected controls. At 2 dpi, the pattern switched into a strong expression of CD172a, CD163, and sialoadhesin by the virulent strains, which was followed by a steep increase in interleukin 8 (IL-8) and soluble CD163 in serum at 3 to 4 dpi. The early increase in surface expression of CD163 induced by nonvirulent strains went along with higher levels of IL-8 in serum than those induced by virulent strains in the first 2 days of infection. Alpha interferon (IFN-α) induction was observed only in animals infected with nonvirulent strains. Overall, these results are compatible with a delay in macrophage activation by virulent strains, which may be critical for disease production.  相似文献   
87.

Acute gastroenteritis (AGE) is a leading cause of disease worldwide. The aim of this prospective observational study is to describe the epidemiology of AGE in closed and semi-closed institutions in Catalonia. In 2017, 151 outbreaks were reported; 30.5% occurred in closed and semi-closed institutions; 71.7% caused by norovirus (NoV) (1532) cases. Person-to-person transmission accounted for 75.8% of NoV outbreaks vs 46.1% in non-NoV outbreaks (p?<?0.001). Attack rate for NoV outbreaks was 33.1% vs 14.3% for non-NoV outbreaks (RR?=?2.3; 95%CI: 2.0–2.7). The high number of affected underscores prompt and intense preventive measures to avoid the extension and perpetuation of outbreaks in these settings.

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88.
89.
The aim of this study was to analyse changes in radicular dentine composition after different irrigation regimes using attenuated total reflectance Fourier‐transform infrared spectroscopy (ATR‐FTIR). Dentine slices from human single‐root teeth were immersed in: (i) 5.25% sodium hypochlorite (NaOCl) for 1, 5 and 20 min; (ii) 17% EDTA for 1 min; and (iii) 5.25% NaOCl for 20 min, and 17% EDTA and 5.25% NaOCl, both for 1 min. Carbonate/mineral, Amide I/mineral and Amide III/CH2 ratios were determined using ATR‐FTIR before and after immersion in the irrigation solutions tested. Results showed that 5.25% NaOCl significantly decreased carbonate/mineral, Amide I/mineral and Amide III/CH2 ratios (P < 0.05). Application of 17% EDTA produced no change in carbonate/mineral ratio (P = 0.120), while an increase in Amide I/mineral in apical third (P = 0.002) and Amide III/CH2 (P < 0.001) was observed. The combination of NaOCl, EDTA and NaOCl increased carbonate/mineral ratio in coronal third (P = 0.037), and Amide I/mineral (P = 0.003) and Amide III/CH2 (P = 0.001) ratios. In conclusion, irrigation solutions tested significantly affected radicular dentine composition.  相似文献   
90.
Cryopreservation of hematopoietic stem cells (HSC) involves slow rate cooling in the presence of a cryoprotectant (DMSO) to avoid the damaging effects of intracellular ice formation. The infusion of DMSO with the thawed product has been related to adverse events. Reduction of DMSO content by washing the HSCs after thawing has been suggested as a method to avoid infusion-related side-effects. Albumin-dextran washing methods have proved useful in thawing HSC products. Dextran40 shortages prompted us to search for suitable alternatives. We report the results of a comparative study of the use of hydroxyethyl starch (HES) as an alternative to dextran40 for washing thawed HSCs products. A total of 10 HSC bags cryopreserved with 10 % DMSO were used. We conducted a paired study; one of the bags was thawed and washed with our standard washing solution (Dextran 40) and the paired bag with HES solution with a final HES and Human Serum Albumin (HSA) concentration of 2.4 % and 4.2 % respectively. Each final product was tested immediately after washing (sample 0’) and after 90 min (sample 90’) for total nucleated cells (TNC) recovery, acridine orange viability, viable CD34+ enumeration, and clonogenicity. No significant difference was found for any of the cell counts, viability tests, cell recovery, or potency. We can state that the washing solution based on 2.4 % HES and 4.2 % HSA is equivalent to that used in our routine practice. Therefore, we could use the solution with HES, paying special attention to the renal function of the recipient.  相似文献   
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