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Air quality within and around confined animal housing operations is important from both occupational exposure and environmental quality perspectives. Appropriate sampling equipment should be available so that bioaerosols are adequately characterized in terms of their component microbial populations. In this study the efficacy of a commercially available impaction-based bioaerosol sampler (SAS-100) was evaluated in terms of its ability to detect male-specific coliphages within and around poultry broiler houses. In addition to the manufacturer recommended agar medium, cellulose and cellulose-acetate filter media were also used as the collection surface. The agar medium and the cellulose ester filters provided very high recoveries of phages as compared to the cellulose filter (P<0.05). There was a wide range of recoveries ranging from 0–100% when the cellulose acetate filter was used to detect phages in bioaerosols within and around broiler houses. The results suggest that the sampler is capable of concentrating male-specific coliphages from bioaerosols. However, further studies are still needed to accurately determine the collection efficiencies of viruses.  相似文献   
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This guidance details the needs of children, and the qualities of parenting that meet those needs. Parental mental disorders can damage the foetus during pregnancy through the action of drugs, prescribed or abused. Pregnancy and the puerperium can exacerbate or initiate mental illness in susceptible women. After their birth, the children may suffer from the social disadvantage associated with severe mental illness. The parents (depending on the disorder, its severity and its persistence) may have intermittent or prolonged difficulties with parenting, which may sometimes result in childhood psychological disturbance or child maltreatment. This guidance considers ways of preventing, minimizing and remedying these effects. Our recommendations include: education of psychiatrists and related professions about the effect of parental mental illness on children; revision of psychiatric training to increase awareness of patients as caregivers, and to incorporate relevant assessment and intervention into their treatment and rehabilitation; the optimum use of pharmacological treatment during pregnancy; pre-birth planning when women with severe mental illness become pregnant; development of specialist services for pregnant and puerperal women, with assessment of their efficacy; community support for parenting by mothers and fathers with severe mental disorders; standards of good practice for the management of child maltreatment when parents suffer from mental illness; the importance of multi-disciplinary teamwork when helping these families, supporting their children and ensuring child protection; the development of child and adolescent mental health services worldwide.  相似文献   
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The diversity of the Iberian vascular flora has been investigated using WORLDMAP versions 3.08 and 3.18. Two data sets scoring plant distributions as presences within the Iberian Peninsula were compiled; one for 2133 species at 50 × 50 km grid and the other for 801 species at 10 × 10 km map grids. Patterns of biodiversity were determined using the diversity measures of species richness, range-size rarity and character richness diversity. Using the diversity measures, combined with an area selection method, maps of priority areas were calculated using iterative procedures. Near minimum sets (NMSs) for both scales were calculated. Comparison of the NMS for the 10 × 10 km grid with the near minimum set for existing reserves (NMSER) showed that at least 2% more of the land surface would be required above and beyond the existing protected area network, currently comprising 6% of the area, to ensure representation of all species at least once as listed within the present data-base. It is demonstrated that reserve systems selected on a variety of different criteria are suboptimal when compared to particular groups of target organisms with a definite goal of representation for conservation. Calculating efficiency of existing reserve systems and accounting for all taxa identifies precisely the extra required areas for the protected area system to satisfy particular goals of representation.  相似文献   
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The products of cell-free ATP incorporation mediated by cytoplasmic fractions prepared from unfertilized sea urchin eggs, anucleate egg halves, nucleate egg halves, emetine-treated fertilized eggs, and four-cell embryos have been characterized to determine to what extent the polymers synthesized are poly(A) and to assess the size distribution of the primers adenylated. As judged by alkaline lability, ribonuclease resistance, and retention on poly(U)-impregnated filters, greater than 92% of the label recovered after RNA extraction is present in poly(A). LiCl fractionation indicates that little, if any, free poly(A) is synthesized or cleaved from RNA primers during the reaction, and that 4S RNA is not an effective initiator. In excess of 85% of the poly(A) is associated with RNA having S-values greater than or equal to 18S. Sedimentation profiles of RNA adenylated in the unfertilized egg and anucleate egg half reactions are identical. Suppression of in vivo protein synthesis by emetine alters the profile of RNA subsequently adenylated in vitro. It is proposed that the apparent constraints on the utilization of cytoplasmic RNA or ribonucleoprotein primers of oogenic origin may be effected by RNA-associated proteins capable of regulating the selection and/or extent of their polyadenylation during early embryogenesis.  相似文献   
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To evaluate the presence of androgen receptors in the human melanoma cell line IIBMEL-J, a Scatchard plot analysis was performed. Cells in culture revealed a single binding component with an apparent dissociation constant (KD) at 37°C of 11 nM and a binding capacity of 326 fmol/mg protein when measured with [3H]-R1881. Competition analysis revealed an atypical relaxation of specificity, since not only androgen (testosterone, dihydrotestosterone [DHT], R1881) and antiandrogen (hydroxy-flutamide [OH-FLU]) competed for [3H]-R1881 binding, but also estradiol, progesterone, and cortisol at 500-fold excess concentration. Binding of [3H]-estradiol and [3H]-R5020 in the absence of unlabeled DHT were completely suppressed in its presence. Immunohistochemistry of androgen receptor with a monoclonal antibody showed that nuclei were vigorously stained. Different doses of flutamide (FLU) and OH-FLU tested on cultured IIB-MEL-J cells in the presence of serum inhibited significantly cell proliferation in a dose-dependent manner. When cells were incubated with 10 nM DHT and 1%charcoal-adsorbed serum, a significant stimulation of growth that was observed was inhibited by 4 μM OH-FLU. DHT stimulation was completely reversed by the antiestrogen tamoxifen. In addition, male nude mice transplanted with IIB-MEL-J tumor were treated with FLU when tumors were palpable. FLU was effective in diminishing tumor growth and increasing survival rate of the animals. As a conclusion, the presence of functional androgen receptors in these cells has been demonstrated by growth inhibition in vitro and in vivo with antiandrogens, and their atypical nature is suggested by binding cross-reactivity and competition studies.  相似文献   
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Tomato yellow leaf curl virus (TYLCV) was recently divided into two different species: Tomato yellow leaf curl virus‐Israel (TYLCV‐Is) and Tomato yellow leaf curl virus‐Sardinia (TYLCV‐Sar). There are no rapid methods by which TYLCV viruses may be assigned to either TYLCV‐Is or TYLCV‐Sar species. In the present work, using an extensive alignment of begomovirus sequences, TYLCV‐specific primers were designed and tested which allow the specific amplification of DNA fragments from any isolate of TYLCV. Also, a primer was designed and tested which allows the specific amplification of TYLCV‐Sar. Furthermore, a combination of these primers was selected to develop a duplex PCR method, which has the potential to detect either TYLCV‐Is or TYLCV‐Sar. The PCR methods were also highly effective with minimal sample preparation and allowed direct amplification of TYLCV from infected leaf extracts. This approach may be used in the laboratory as a tool for rapid, large‐scale diagnostics of TYLCV‐infected samples.  相似文献   
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