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51.

Purpose

Epidemiologic data on whether consumption of fruit and vegetables (FVs) decreases the risk of gallstone disease are sparse. Therefore, we examined the association between FV consumption and the 14-year risk of symptomatic gallstone disease (defined as occurrence of cholecystectomy) in a large group of middle-aged and elderly persons.

Methods

Data from two population-based cohorts were used, which included 74,554 men and women (born 1914–1952). Participants filled in a food frequency questionnaire in the late fall of 1997 and were followed up for cholecystectomy between 1998 and 2011 via linkage to the Swedish Patient Register. Cox regression models were used to obtain hazard ratios (HRs).

Results

During 939,715 person-years of follow-up, 2120 participants underwent a cholecystectomy (1120 women and 1000 men). An inverse association between FV consumption and risk of cholecystectomy was observed in age- and sex-adjusted analyses (P trend = .036) but not in confounder-adjusted analyses (P trend = .43). The multivariable-adjusted HR was 0.95 (95 % CI 0.83–1.08) for the highest compared with the lowest sex-specific quartile of FV consumption. There was no evidence of interactions with age (P = .25) or sex (P = .72) in analyses pooled by sex. However, an age-by-FV consumption interaction was observed in separate analyses of women (P = .010), with decreased HRs of cholecystectomy for ages up to 60 years.

Conclusions

This study supports an inverse association between FV consumption and risk cholecystectomy in women, although the association was restricted to women aged 48–60 years. In contrast, the study does not support an association in men.
  相似文献   
52.
53.
Thousands of tons of zeolitic materials are used yearly as soil conditioners and components of slow-release fertilizers. A positive influence of application of zeolites on plant growth has been frequently observed. Because zeolites have extremely large cation exchange capacity, surface area, porosity and water holding capacity, a paradigm has aroused that increasing plant growth is caused by a long-lasting improvement of soil physicochemical properties by zeolites. In the first year of our field experiment performed on a poor soil with zeolite rates from 1 to 8 t/ha and N fertilization, an increase in spring wheat yield was observed. Any effect on soil cation exchange capacity (CEC), surface area (S), pH-dependent surface charge (Qv), mesoporosity, water holding capacity and plant available water (PAW) was noted. This positive effect of zeolite on plants could be due to extra nutrients supplied by the mineral (primarily potassium—1 ton of the studied zeolite contained around 15 kg of exchangeable potassium). In the second year of the experiment (NPK treatment on previously zeolitized soil), the zeolite presence did not impact plant yield. No long-term effect of the zeolite on plants was observed in the third year after soil zeolitization, when, as in the first year, only N fertilization was applied. That there were no significant changes in the above-mentioned physicochemical properties of the field soil after the addition of zeolite was most likely due to high dilution of the mineral in the soil (8 t/ha zeolite is only ~0.35% of the soil mass in the root zone). To determine how much zeolite is needed to improve soil physicochemical properties, much higher zeolite rates than those applied in the field were studied in the laboratory. The latter studies showed that CEC and S increased proportionally to the zeolite percentage in the soil. The Qv of the zeolite was lower than that of the soil, so a decrease in soil variable charge was observed due to zeolite addition. Surprisingly, a slight increase in PAW, even at the largest zeolite dose (from 9.5% for the control soil to 13% for a mixture of 40 g zeolite and 100 g soil), was observed. It resulted from small alterations of the soil macrostructure: although the input of small zeolite pores was seen in pore size distributions, the larger pores responsible for the storage of PAW were almost not affected by the zeolite addition.  相似文献   
54.
Shiga toxin-converting bacteriophages (Stx phages) are present as prophages in Shiga toxin-producing Escherichia coli (STEC) strains. Theses phages can be transmitted to previously non-pathogenic E. coli cells making them potential producers of Shiga toxins, as they bear genes for these toxins in their genomes. Therefore, sensitivity of Stx phage virions to various conditions is important in both natural processes of spreading of these viruses and potential prophylactic control of appearance of novel pathogenic E. coli strains. In this report we provide evidence that virions of Stx phages are significantly more sensitive to UV irradiation than bacteriophage λ. Following UV irradiation of Stx virions at the dose of 50 J/m2, their infectivity dropped by 1–3 log10, depending on the kind of phage. Under these conditions, a considerable release of phage DNA from virions was observed, and electron microscopy analyses indicated a large proportion of partially damaged virions. Infection of E. coli cells with UV-irradiated Stx phages resulted in significantly decreased levels of expression of N and cro genes, crucial for lytic development. We conclude that inactivation of Stx virions caused by relatively low dose of UV light is due to damage of capsids that prevents effective infection of the host cells.  相似文献   
55.
The polymerase chain reaction (PCR) and indirect immunofluorescent test (IF) were used for examination of serum samples obtained from infants with respiratory tract infections. Sixty (11.9%) out of the 503 examined infant samples were positive for anti-P. carinii IgM and 354 (70.4%) contained anti-Pneumocystis IgG. P. carinii DNA was found in 6 (6.7%) sera from 90 of infected infants. Five out these 6 samples were for anti-Pneumocystis antibodies positive; 4 contained both IgG and IgM classes and one had only IgG. The sixth sample had neither IgG nor IgM, despite of P. carinii DNA presence. The results of the studies indicated that for diagnosis Pneumocystis carinii pneumonia (PCP) in infants on serum specimens detection of antibodies by IF test is of greater value than Pneumocystis DNA amplification by PCR method.  相似文献   
56.

Background

Adherence to a combination of healthy dietary and lifestyle practices may have an impressive impact on the primary prevention of myocardial infarction (MI).

Objectives

The aim of this study was to examine the benefit of combined low-risk diet and healthy lifestyle practices on the incidence of MI in men.

Methods

The population-based, prospective cohort of Swedish men comprised 45- to 79-year-old men who completed a detailed questionnaire on diet and lifestyle at baseline in 1997. In total, 20,721 men with no history of cancer, cardiovascular disease, diabetes, hypertension, or high cholesterol levels were followed through 2009. Low-risk behavior included 5 factors: a healthy diet (top quintile of Recommended Food Score), moderate alcohol consumption (10 to 30 g/day), no smoking, being physically active (walking/bicycling ≥40 min/day and exercising ≥1 h/week), and having no abdominal adiposity (waist circumference <95 cm).

Results

During 11 years of follow-up, we ascertained 1,361 incident cases of MI. The low-risk dietary choice together with moderate alcohol consumption was associated with a relative risk of 0.65 (95% confidence interval [CI]: 0.48 to 0.87) compared with men having 0 of 5 low-risk factors. Men having all 5 low-risk factors compared with those with 0 low-risk factors had a relative risk of 0.14 (95% CI: 0.04 to 0.43). This combination of healthy behaviors, present in 1% of the men, could prevent 79% (95% CI: 34% to 93%) of the MI events on the basis of the study population.

Conclusions

Almost 4 of 5 MIs in men may be preventable with a combined low-risk behavior.  相似文献   
57.
Lysosomal storage diseases are inherited metabolic disorders caused by genetic defects causing deficiency of various lysosomal proteins, and resultant accumulation of non-degraded compounds. They are multisystemic diseases, and in most of them (>70 %) severe brain dysfunctions are evident. However, expression of various phenotypes in particular diseases is extremely variable, from non-neuronopathic to severely neurodegenerative in the deficiency of the same enzyme. Although all lysosomal storage diseases are monogenic, clear genotype-phenotype correlations occur only in some cases. In this article, we present an overview on various factors and processes, both general and specific for certain disorders, that can significantly modulate expression of phenotypes in these diseases. On the basis of recent reports describing studies on both animal models and clinical data, we propose a hypothesis that efficiency of production of compounds that cannot be degraded due to enzyme deficiency might be especially important in modulation of phenotypes of patients suffering from lysosomal storage diseases.  相似文献   
58.
The ability of two-component dyeing photoinitiating systems for the radical polymerization of 1,6-hexanediol diacrylate (HDDA) and 2-ethyl-2-(hydroxymethyl)-1,3-propanediol triacrylate (TMPTA) is presented. The systems under study comprised a hemicyanine dye as a sensitizer and iodonium salts that played a role of a coinitiator. The kinetic parameters of the polymerization reaction, such as the rate of polymerization (Rp) and the degree of conversion of monomer (C%), were estimated. The thermodynamic feasibility of an electron transfer process in the systems studied was verified and calculated using the Rehm–Weller equation. It was found that a benzoxazole derivative in the presence of iodonium salts effectively initiated the polymerization of acrylate monomers. The polymerization rates of about 10−7 s−1 and the degree of conversion of acrylate groups from 20% to 50% were observed. The effects of photoinitiator structures on the initiating ability and spectroscopic properties of sensitizers are described in this article.

The ability of two-component dyeing photoinitiating systems for the radical polymerization of 1,6-hexanediol diacrylate (HDDA) and 2-ethyl-2-(hydroxymethyl)-1,3-propanediol triacrylate (TMPTA) is presented.  相似文献   
59.
Pharmaceutical Chemistry Journal - In this study, iron oxide (Fe3O4) nanoparticles were synthesized using the Massart co-precipitation method followed by surface coating with dextran. Next, coated...  相似文献   
60.
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