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51.
Plant Cell, Tissue and Organ Culture (PCTOC) - Lychnis flos-cuculi L. is a species containing ecdysteroids, triterpenoid saponins, flavonoids, and phenolic acids, and therefore is a plant of...  相似文献   
52.
DNA content was estimated by flow cytometry in seedlings and in vitro clones of six species: Oenothera paradoxa, Inula verbascifolia ssp. aschersoniana, Rubus chamaemorus, Solidago virgaurea, S. graminifolia and Pueraria lobata. With the exception of P. lobata, there was no difference in genome sizes between seedlings and in vitro cultured plants from any species, indicative that they maintain their genetic stability during in vitro culture. This confirms the usefulness of tissue culture for production of certified plant material to obtain herbal medicines.  相似文献   
53.

Background

Killed oral cholera vaccines (OCVs) are available but not used routinely for cholera control except in Vietnam, which produces its own vaccine. In 2007–2008, unprecedented cholera outbreaks occurred in the capital, Hanoi, prompting immunization in two districts. In an outbreak investigation, we assessed the effectiveness of killed OCV use after a cholera outbreak began.

Methodology/Principal Findings

From 16 to 28 January 2008, vaccination campaigns with the Vietnamese killed OCV were held in two districts of Hanoi. No cholera cases were detected from 5 February to 4 March 2008, after which cases were again identified. Beginning 8 April 2008, residents of four districts of Hanoi admitted to one of five hospitals for acute diarrhea with onset after 5 March 2008 were recruited for a matched, hospital-based, case-control outbreak investigation. Cases were matched by hospital, admission date, district, gender, and age to controls admitted for non-diarrheal conditions. Subjects from the two vaccinated districts were evaluated to determine vaccine effectiveness. 54 case-control pairs from the vaccinated districts were included in the analysis. There were 8 (15%) and 16 (30%) vaccine recipients among cases and controls, respectively. The vaccine was 76% protective against cholera in this setting (95% CI 5% to 94%, P = 0.042) after adjusting for intake of dog meat or raw vegetables and not drinking boiled or bottled water most of the time.

Conclusions/Significance

This is the first study to explore the effectiveness of the reactive use of killed OCVs during a cholera outbreak. Our findings suggest that killed OCVs may have a role in controlling cholera outbreaks.  相似文献   
54.

Background

Aedes aegypti, the major vector of dengue viruses, often breeds in water storage containers used by households without tap water supply, and occurs in high numbers even in dense urban areas. We analysed the interaction between human population density and lack of tap water as a cause of dengue fever outbreaks with the aim of identifying geographic areas at highest risk.

Methods and Findings

We conducted an individual-level cohort study in a population of 75,000 geo-referenced households in Vietnam over the course of two epidemics, on the basis of dengue hospital admissions (n = 3,013). We applied space-time scan statistics and mathematical models to confirm the findings. We identified a surprisingly narrow range of critical human population densities between around 3,000 to 7,000 people/km2 prone to dengue outbreaks. In the study area, this population density was typical of villages and some peri-urban areas. Scan statistics showed that areas with a high population density or adequate water supply did not experience severe outbreaks. The risk of dengue was higher in rural than in urban areas, largely explained by lack of piped water supply, and in human population densities more often falling within the critical range. Mathematical modeling suggests that simple assumptions regarding area-level vector/host ratios may explain the occurrence of outbreaks.

Conclusions

Rural areas may contribute at least as much to the dissemination of dengue fever as cities. Improving water supply and vector control in areas with a human population density critical for dengue transmission could increase the efficiency of control efforts. Please see later in the article for the Editors'' Summary  相似文献   
55.

Background

Pain and musculoskeletal complaints are among the most common symptoms in the general population. Despite their epidemiological, clinical and health economic importance, prevalence data on pain and musculoskeletal complaints for Germany are scarce.

Methods

A cross-sectional survey of a random sample of citizens of Herne, Germany, aged ≥ 40 years was performed. A detailed self-complete postal questionnaire was used, followed by a short reminder questionnaire and telephone contacts for those not responding. The questionnaire contained 66 items, mainly addressing pain of any site, musculoskeletal complaints of any site and of knee and hip, pain intensities, the Western Ontario MacMaster Universities (WOMAC) index, medication, health care utilization, comorbidities, and quality of life.

Results

The response rate was 57.8% (4,527 of 7,828 individuals). Survey participants were on average 1.3 years older, and the proportion of women among responders tended to be greater than in the population sample. There was no age difference between the population sample and 2,221 participants filling out the detailed questionnaire. The following standardized prevalences were assessed: current pain: 59.7%, pain within the past four weeks: 74.5%, current joint complaints: 49.3%, joint complaints within the past four weeks and twelve month: 62.8% and 67.4%, respectively, knee as the site predominantly affected: 30.9%, knee bilateral: 9.7%, hip: 15.2%, hip bilateral: 3.5%, knee and hip: 5.5%. Pain and musculoskeletal complaints were significantly more often reported by women. A typical relationship of pain and joint complaints to age could be found, i.e. increasing prevalences with increasing age categories, with a drop in the highest age groups. In general, pain and joint pain were associated with comorbidity and body mass index as well as quality of life.

Conclusions

Our data confirm findings of other recent national as well as European surveys. The high site specific prevalences of knee and hip complaints underline the necessity to further investigate characteristics and consequences of pain and symptomatic osteoarthritis of these joints in adults in Germany.  相似文献   
56.

Aim

Changing preferences regarding which species humans have transported to new regions can have major consequences for the potential distribution of alien taxa, but the mechanisms shaping these patterns are poorly understood. We assessed the extent to which changes in human preferences for transporting and introducing alien freshwater fishes have altered their biogeography.

Location

Australia.

Methods

We compiled an up‐to‐date database of alien freshwater fishes established in drainages in Australia before and after the number of established alien fish species doubled (pre‐1970 and post‐1970, respectively). Using metacommunity models, we analysed the influence of species traits and drainage features on the distribution of alien fishes that established pre‐ and post‐1970.

Results

Alien fishes in Australia were introduced via four main transport pathways: acclimatization, aquaculture, biocontrol and ornamental trade. The relative importance of each pathway changed substantially between the two periods, accompanied by changes in the distribution of alien fishes and the variables predicting their distribution. Pre‐1970, most species (64%) were introduced by acclimatization societies for purposes such as angling and biocontrol, and these fish have established in inland drainages more heavily impacted by human activities. In contrast, most of the post‐1970 introductions (69%) were ornamental fishes, with most species established in small, north‐eastern, tropical and subtropical coastal drainages.

Main conclusions

Substantial changes in introduction preferences and transport pathways over time have altered both the patterns and underlying processes shaping the biogeography of alien fishes in Australia. Our findings highlight the need for caution when using historical data to infer potential future distributions of alien species. The continuing spread of alien species means traditional biogeographical units may no longer be identifiable in the foreseeable future.
  相似文献   
57.
Radio-tracking was used in monitoring the reintroduction of on-grown 2 year-old trout cod Maccullochella macquariensis (Percichthyidae) (a nationally endangered freshwater fish) in both a large and small upland river. Thirty-six radio-tagged M. macquariensis were stocked into a site in each of the Murrumbidgee and Cotter Rivers (Australian Capital Territory). Restricted dispersal occurred in both rivers, with both samples of M. macquariensis remaining within 5 km of the release site for the duration of the study. Mortality was rapid and 1 month after release 61 and 31% of the sample was alive in the Murrumbidgee and Cotter Rivers, respectively. In the Murrumbidgee River, complete mortality had occurred 6 months after release. An individual survived in the Cotter River until 7 months after release. Predation by cormorants Phalacrocorax spp. and predation or scavenging by the common water rat Hydromys chrysogaster were the probable causes of mortality. Predator-assisted movement of radio-tags by cormorants occurred in both groups and had the potential to confound interpretation of active dispersal movements.  相似文献   
58.
Plant Cell, Tissue and Organ Culture (PCTOC) - Phenolic acids and flavonoids, important bioactive compounds of polyphenols, play a significant role in plants; their impact, mainly as antioxidants,...  相似文献   
59.
60.
Membrane-bound beta-Gal-3'-sulfotransferase (GP3ST) was expressed and used for in vitro sulfation of Tamm-Horsfall glycoprotein. Further, the regioselective transfer of sulfate to an N-acetyllactosamine derivative could be realised with soluble chimeric GP3ST, also in combination with Lac transglycosylation by means of beta-galactosidase. Two alternative straightforward chemical syntheses for the target compound could be elaborated.  相似文献   
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