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21.
Mammillaria gracilis Pfeiff. plants cultivated in the pot (pot plants, PP), as well as in vitro-grown normal shoots (NS), habituated callus (HC), hyperhydric shoots (HS), and tumour tissue (TT) were investigated in order to reveal the influence of in vitro culture on functionality of the photosynthetic apparatus and CAM photosynthesis in cactus M. gracilis Pfeiff. Photosynthetic pigments content as well as maximum (F v/F m) and effective (??PSII) quantum yield of photosystem II (PSII) decreased in all in vitro-grown tissues in comparison to PP. The decrease observed in hyperhydric HC, HS and TT correlated with a low expression of Rubisco large subunit (RbcL) and ?? subunit of ATP synthase (?? ATP synt) and almost undetectable levels of protein D1, light-harvesting chlorophyll a/b-binding protein (LHCII) and cytochrome f protein of thylakoid Cyt b 6 /f-complex (Cyt f) found in these tissues. As for crassulacean acid metabolism (CAM) pattern, PP and NS expressed diurnal acid fluctuation, while HC, HS and TT failed to show it. Nevertheless, all M. gracilis tissues exhibited diurnal changes of phosphoenolpyruvate carboxylase (PEPC) activity indicating the typical CAM physiology. In conclusion, the photosynthesis was down-regulated in all in vitro-grown tissues. NS maintained typical CAM photosynthesis, while HC, HS and TT withheld PEPC activity, but not acid accumulation specific for CAM. Minor changes observed in NS in comparison to PP could be attributed to the sugar supplementation while the more prominent deviations found in HC, HS and TT could be correlated with hyperhydricity and the loss of characteristic tissue organisation pattern.  相似文献   
22.
The content of biologically active phenolic compounds (total polyphenols, tannins, flavonoids, and phenolic acids) were determined using spectrophotometry in four wild Croatian species of Daphne L. in the family Thymelaeaceae (Daphne alpina, D. cneorum, D. laureola, and D. mezereum). The concentration of total flavonoids (TF) was highest in the leaves of these Daphne species (0.12?C0.51% dry herb weight, DW) whereas the content of other phenolic compounds analyzed were highest in the roots, including total polyphenols (TP; 2.71?C19.03% DW), tannins (T; 1.14?C7.39% DW), and total phenolic acids (TPA; 0.12?C0.87% DW). D. alpina contained the highest amount of polyphenols, with the exception of flavonoids, where maximum concentrations were found in D. laureola. We also examined the antioxidant activity of leaf, stem, and root extracts. All extracts analyzed demonstrated high free radical scavenging activity with the highest concentration in the leaf extracts of D. alpina. Leaf extracts of D. cneorum showed the highest antioxidant activity in a ??-carotene bleaching assay.  相似文献   
23.
It has already been shown that tetanus toxoid (TTd) hyper-immunization is a suitable experimental method for creating the animal model of antiphospholipid syndrome (APS) in BALB/c mice. The severity of APS pathology in BALB/c mice mainly correlates to the affinity of anti-β(2) glycoprotein I (β(2)GPI) antibodies. In this study we have investigated reproductive pathology induced in C57BL/6 mice by TTd hyper-immunization using a combination of different pretreatments (complete Freund's adjuvant or glycerol) and adjuvants (alhydrogel or glycerol). A decrease in fecundity was recorded in only C57BL/6 mice immunized with alhydrogel adjuvant, irrespective of the kind of applied pretreatment; it was associated with an increase in abundance of low affinity anti-β(2)GPI IgG antibodies and Th1 prevalence.  相似文献   
24.
BackgroundOut-of-hospital cardiac arrest (OHCA) remains a major public health issue and research has shown that large regional variation in outcomes exists. Of the interventions associated with survival, the provision of bystander CPR is one of the most important modifiable factors. The aim of this study is to identify census areas with high incidence of OHCA and low rates of bystander CPR in Victoria, AustraliaMethodsWe conducted an observational study using prospectively collected population-based OHCA data from the state of Victoria in Australia. Using ArcGIS (ArcMap 10.0), we linked the location of the arrest using the dispatch coordinates (longitude and latitude) to Victorian Local Government Areas (LGAs). We used Bayesian hierarchical models with random effects on each LGA to provide shrunken estimates of the rates of bystander CPR and the incidence rates.ResultsOver the study period there were 31,019 adult OHCA attended, of which 21,436 (69.1%) cases were of presumed cardiac etiology. Significant variation in the incidence of OHCA among LGAs was observed. There was a 3 fold difference in the incidence rate between the lowest and highest LGAs, ranging from 38.5 to 115.1 cases per 100,000 person-years. The overall rate of bystander CPR for bystander witnessed OHCAs was 62.4%, with the rate increasing from 56.4% in 2008–2010 to 68.6% in 2010–2013. There was a 25.1% absolute difference in bystander CPR rates between the highest and lowest LGAs.ConclusionSignificant regional variation in OHCA incidence and bystander CPR rates exists throughout Victoria. Regions with high incidence and low bystander CPR participation can be identified and would make suitable targets for interventions to improve CPR participation rates.  相似文献   
25.
The development of photochemical activities in isolated barley plastids during illumination of dark-grown plants has been studied and compared with the behaviour of plastocyanin, cytochromes f, b-559LP, b-563 and b-559HP and pigments P546 (C550) and P700. Electron-transport activity dependent on Photosystem 1 and cyclic photophosphorylation dependent on N-methylphenazonium methosulphate (phenazine methosulphate) were very active relative to the chlorophyll content after only a few minutes of illumination of etiolated leaves, and then rapidly declined during the first few hours of greening. By contrast, Photosystem 2 activity (measured with ferricyanide as electron acceptor) and non-cyclic photophosphorylation were not detectable during the first 2½h of greening, but then increased in total amount in parallel with chlorophyll. The behaviour of the electron carriers suggested their association with either Photosystem 1 or 2 respectively. In the first group were plastocyanin, cytochrome f and cytochrome b-563, whose concentrations in the leaf did not change during greening, and cytochrome b-559LP whose concentration fell to one-half its original value, and in the second group were cytochrome b-559HP and pigment P546, the concentrations of which closely followed the activities of Photosystem 2. Pigment P700 could not be detected during the first hour, during which time some other form of chlorophyll may take its place in the reaction centre of Photosystem 1. The plastids started to develop grana at about the time that Photosystem 2 activity became detectable.  相似文献   
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27.
The Bayash are a branch of Romanian speaking Roma living dispersedly in Central, Eastern, and Southeastern Europe. To better understand the molecular architecture and origin of the Croatian Bayash paternal gene pool, 151 Bayash Y chromosomes were analyzed for 16 SNPs and 17 STRs and compared with European Romani and non-Romani majority populations from Europe, Turkey, and South Asia. Two main layers of Bayash paternal gene pool were identified: ancestral (Indian) and recent (European). The reduced diversity and expansion signals of H1a patrilineages imply descent from closely related paternal ancestors who could have settled in the Indian subcontinent, possibly as early as between the eighth and tenth centuries AD. The recent layer of the Bayash paternal pool is dominated by a specific subset of E1b1b1a lineages that are not found in the Balkan majority populations. At least two private mutational events occurred in the Bayash during their migrations from the southern Balkans toward Romania. Additional admixture, evident in the low frequencies of typical European haplogroups, J2, R1a, I1, R1b1b2, G, and I2a, took place primarily during the early Bayash settlement in the Balkans and the Romani bondage in Romania. Our results indicate two phenomena in the Bayash and analyzed Roma: a significant preservation of ancestral H1a haplotypes as a result of considerable, but variable level of endogamy and isolation and differential distribution of less frequent, but typical European lineages due to different patterns of the early demographic history in Europe marked by differential admixture and genetic drift.  相似文献   
28.
Psoriasis is a disease with a profound impact on the psychological and social aspects of the patient, particularly because of its visibility. Quality of life is impaired and different mental health disorders like depression, anxiety, alcoholism, posttraumatic stress disorder (PTSD) are found among persons suffering from psoriasis. Studies have shown the influence of stressful life events on onset, exacerbation and relapse of psoriasis. Rare studies explored prevalence of psoriasis during war times and relations between psoriasis and war provoked PTSD. Psoriasis is a disease with multiple possible causes and additional caution is necessary among medical professional to recognize all contributing factors. This report describes a case of a person whose first episode of psoriasis appeared six months after engaging in combat activities. He is diagnosed with psoriasis vulgaris, psoriatic arthritis and permanent personality changes after the traumatic experiences caused by war participation. His occupational history is burdened with additional causational factors; work with heavy metals and metal dusts. Cumulative effects of different aetiological factors can contribute to psoriasis with intensive trauma induced stressors serving as a trigger. His medical history indicates cognitive difficulties typical for early dementia which makes this case even more interesting. Research results suggesting common aetiology of psoriasis, autoimmune diseases and neurodegenerative diseases, indicate a need, as in the case of our patient, for multidisciplinary approach to studying aetiology of psoriasis.  相似文献   
29.
The aim of this research was to determine the role of gender, type of residence, living arrangement, self-rated health status, loneliness, and sense of humor in self-reported life satisfaction in elderly retirees. The study included 300 elderly retirees from Zagreb, Croatia. Demographic data were collected with a structured questionnaire, whereas data on self-reported health status, loneliness, and sense of humor were collected with the UCLA Loneliness Scale, Life Satisfaction Index, HOPA-86, and SF-36 Health Survey. Participants living in a retirement home showed higher life satisfaction than those who lived in their own households. Those who had children showed greater life satisfaction No differences in life satisfaction were found with respect to gender, marital status, or living arrangement. The investigated demographic variables, self-rated health status, self-rated loneliness, and a sense of humor explained 52.8% of variance in life satisfaction. An active sense of humor was the most significant predictor. Living in a retirement home, having children, and having an active sense of humor had a positive influence on self-reported life satisfaction, whereas poorer self-rated health and loneliness had a negative influence. Taking into account the predictors of life satisfaction in preventive activities may contribute to successful aging.  相似文献   
30.
Fibrodysplasia ossificans progressiva (FOP) is an extremely rare genetic disorder with diffuse extra-skeletal bone formation. The genetic mutation responsible for FOP has recently been discovered and is connected with excessive activation of bone morphogenetic protein receptor. This disease usually begins with typical ossification pattern in early childhood, causing increasing disability and making patients totally disabled by the age of 30. Ectopic ossification develops spontaneously and can be triggered by any trauma and even intramuscular injections. The symptoms of FOP are often misdiagnosed as cancer, causing unnecessary biopsies, which can precipitate further progressive heterotopic ossification. There is no effective treatment for this severe condition. Radiotherapy can be helpful in impeding ossification, although the strict evidence for that is lacking. There are only two reports in the literature referring to the use of radiotherapy in treatment of FOP. Herein, we present a 35-year-old patient successfully treated with small doses of fractionated radiotherapy in several courses. This case indicates that radiotherapy can be useful in treating patients with FOP.  相似文献   
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