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101.
102.
Sebat J Lakshmi B Malhotra D Troge J Lese-Martin C Walsh T Yamrom B Yoon S Krasnitz A Kendall J Leotta A Pai D Zhang R Lee YH Hicks J Spence SJ Lee AT Puura K Lehtimäki T Ledbetter D Gregersen PK Bregman J Sutcliffe JS Jobanputra V Chung W Warburton D King MC Skuse D Geschwind DH Gilliam TC Ye K Wigler M 《Science (New York, N.Y.)》2007,316(5823):445-449
We tested the hypothesis that de novo copy number variation (CNV) is associated with autism spectrum disorders (ASDs). We performed comparative genomic hybridization (CGH) on the genomic DNA of patients and unaffected subjects to detect copy number variants not present in their respective parents. Candidate genomic regions were validated by higher-resolution CGH, paternity testing, cytogenetics, fluorescence in situ hybridization, and microsatellite genotyping. Confirmed de novo CNVs were significantly associated with autism (P = 0.0005). Such CNVs were identified in 12 out of 118 (10%) of patients with sporadic autism, in 2 out of 77 (3%) of patients with an affected first-degree relative, and in 2 out of 196 (1%) of controls. Most de novo CNVs were smaller than microscopic resolution. Affected genomic regions were highly heterogeneous and included mutations of single genes. These findings establish de novo germline mutation as a more significant risk factor for ASD than previously recognized. 相似文献
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104.
Evaluation of effects of transgenic Bt maize on microarthropods in a European multi-site experiment 总被引:2,自引:5,他引:2
Jrme Cortet Bryan S. Griffiths Marko Bohanec Damjan Demsar Mathias N. Andersen Sandra Caul Andrew N. E. Birch Cline Pernin Elisabeth Tabone Annette de Vaufleury Xin Ke Paul Henning Krogh 《Pedobiologia》2007,51(3):207-ECOGEN
The effects of maize expressing the Bacillus thuringiensis Cry1Ab protein (Bt maize) on soil microarthropods were assessed in the field at four European locations (two in Denmark and two in France) that differ in their climatic conditions or soil properties. Each site was considered as a separate experiment, with separate statistical comparison. Effects of farming practices using Bt maize were compared with conventional farming practices using near-isogenic non-Bt maize and also (at some of the sites) other conventional varieties. Furthermore, at one field site (Foulum, Denmark), the effects of Bt crops were studied in both conventional tillage and reduced tillage contexts. At another field site (Askov, Denmark), Bt maize effects were also compared to the effects of the chemical insecticide dimethoate. Moreover, at three of the field sites (all except Narbons, France), the possibility of a localised Bt effect around the rhizosphere compared to the bulk soil was assessed by sampling within and between maize rows. There were some significant negative effects of Bt maize on microarthropods in soils with a high clay content. Significant differences of the same magnitude also occurred between different conventional varieties of maize, but the effect of dimethoate appeared clearly greater than Bt effects. It is thus debatable if the Bt maize effect is an effect of the Bt toxin or just an effect of the maize variety. Based on the results, it can be concluded that the effect of Bt maize on soil microarthropods was small and within the normal variation expected in conventional agricultural systems. 相似文献
105.
This work describes the production of transgenic, fertile plants of soybean [Glycine max (L.) Merrill]. The transformation method combines the advantages of somatic embryo genesis with the efficiency of particle
bombardment of tissues that have a great capacity for in vitro proliferation and regeneration. The results described here represent the first report of transformation of soybean cultivars
recommended for commercial growing in South Brazil using somatic embryogenesis, and may open the field for the improvement
of this crop in this country by genetic engineering.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
106.
107.
108.
Annette Dickinson 《Fitoterapia》2011,82(1):5-10
The Dietary Supplement Health and Education Act (DSHEA), enacted in 1994, had two primary goals: to ensure continued consumer access to a wide variety of dietary supplements, and to provide consumers with more information about the intended use of dietary supplements. It accomplished these goals, and more, without changing the fundamental regulatory status of dietary supplements as a category of foods. This article explores the history and reasoning behind the major provisions of the Act and reflects on the impact of each during 15 years of experience under DSHEA. 相似文献
109.
Nobmann JA Blaha T Beyerbach M Kreienbrock L Meemken D 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(7-8):313-319
The German Salmonella Monitoring Programme started by the QS-System in 2002 (Blaha, 2004) is mandatory due to the so-called "Salmonella Regulation for Pigs" since 2007 (Anonym, 2007). The Regulation does not clearly prescribe the specific muscle which is to be taken as source of the meat juice. Thus, at different slaughter plants meat samples are also taken from different muscles and several scientific papers describe various muscles as source of the meat juice, too. The objective of this study was to compare the serological results of meat juices from three different locations (diaphragm pillar, neck, belly muscle) to each other and to those of the blood serum from exactly the same animals. All samples were simultaneously tested for Salmonella antibodies by two serological tests (Salmo-type Pig Screen, LDL, Germany; HerdChek Swine Salmonella, IDEXX, Germany). Comparisons were carried out between the various sample kinds per animal and between the two test systems. The analysis of all results of the meat juices revealed in both test systems a clear decline of the OD% values from the diaphragm pillar to the neck to the belly muscle. The average OD% values of all samples were higher when measured by the HerdChek ELISA (IDEXX, Germany) than by the Salmotype ELISA (LDL, Germany), especially in blood serum. Since the results of the meat juice samples gained from the diaphragm pillar were in both test systems by far the closest to the results of the corresponding serum blood samples, it is recommended to amend the "Salmonella Regulation for Pigs" by prescribing meat from the diaphragm pillar as the only muscle for gaining meat juice. 相似文献
110.
Nissen S Poulsen IH Nejsum P Olsen A Roepstorff A Rubaire-Akiiki C Thamsborg SM 《Tropical animal health and production》2011,43(3):567-572
During the last 30 years, pig production in Uganda and neighbouring counties has increased markedly. Pigs are mainly kept
as a source of income for small-scale farmers; however, the pig production is subject to several constraints, one of them
being worm infections. A study was carried out in rural communities in Kabale District in the South Western part of Uganda
in September and October 2007 in order to estimate the prevalence of gastrointestinal nematode parasites in pigs based on
coprological examination. Fifty-six households were randomly selected and visited. Housing system and deworming history were
recorded. Faeces was sampled from rectum of one to five pigs (age, 3–12 months) per household. A total of 106 pigs were examined
coprologically of which 91% excreted nematode eggs. The following prevalences of nematode eggs were recorded: strongyles (89%),
Ascaris suum (40%), Trichuris suis (17%) and spiruroid eggs (48%). On household level, rearing pigs on slatted floors in pens significantly reduced the faecal
egg excretion of strongyle eggs with almost 80% (p = 0.010) and a significant interaction between floor type and anthelmintic treatment was found for spiruroids (p = 0.037). Fifteen T. suis egg positive pigs were selected for post-mortem examination of the gastrointestinal tract. The post-mortem examinations revealed
that 93% pigs were infected with Oesophagostomum spp. (worm burden, min–max 10–2,180), 73% with A. suum (1–36), 67% with T. suis (6–58), and 20% with Hyostrongylus rubidus (worms not quantified). In general, nematode infections were widespread and polyparasitism common in pigs in Uganda. However,
worm burdens were moderate which may be related to recent deworming or to the practice of rearing pigs on slatted floors in
wooden elevated pens. 相似文献