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A Drosophila-related expressed sequence tag (DRES) with sequence similarity to the peanut gene has previously been localized to human chromosome 22q11. We have isolated the cDNA corresponding to this DRES and show that it is a novel member of the family of septin genes, which encode proteins with GTPase activity thought to interact during cytokinesis. The predicted protein has P-loop nucleotide binding and GTPase motifs. The gene, which we call PNUTL1, maps to the region of 22q11.2 frequently deleted in DiGeorge and velo-cardio-facial syndromes and is particularly highly expressed in the brain. The mouse homologue, Pnutl1, maps to MMU16 adding to the growing number of genes from the DiGeorge syndrome region that map to this chromosome.  相似文献   
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This paper documents an exercise to synthesize and assess the best available scientific knowledge on the effectiveness of different farm practices at enhancing natural pest regulation in agriculture. It demonstrates a novel combination of three approaches to evidence synthesis—systematic literature search, collated synopsis and evidence assessment using an expert panel. These approaches follow a logical sequence moving from a large volume of disparate evidence to a simple, easily understandable answer for use in policy or practice. The example of natural pest regulation in agriculture was selected as a case study within two independent science-policy interface projects, one European and one British. A third funder, a private business, supported the final stage to translate the synthesized findings into a useful, simplified output for agronomists. As a whole, the case study showcases how a network of scientific knowledge holders and knowledge users can work together to improve the use of science in policy and practice. The process identified five practices with good evidence of a benefit to natural pest regulation, with the most beneficial being ‘Combine trap and repellent crops in a push–pull system’. It highlights knowledge gaps, or potential research priorities, by showing practices considered important by stakeholders for which there is not enough evidence to make an assessment of effects on natural pest regulation, including ‘Alter the timing of pesticide application.’ Finally, the process identifies several important practices where the volume of evidence of effects on natural pest regulation was too large (>300 experimental studies) to be summarised with the resources available, and for which focused systematic reviews may be the best approach. These very well studied practices include ‘Reduce tillage’ and ‘Plant more than one crop per field’.  相似文献   
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Saturation and competitive binding analyses demonstrated the presence of a high affinity (KD = 0.92 nM), specific antiestrogen binding site (AEBS) in rat liver microsomes and at least 75% of total liver AEBS was recovered in this fraction. When microsomes were further separated into smooth and rough fractions, AEBS was concentrated in the latter. Subsequent dissociation of ribosomes from the rough membranes revealed that AEBS was associated with the membrane and not the ribosomal fraction. Antiestrogen binding activity could not be extracted from membranes with 1 M KCl or 0.5 M acetic acid but could be solubilized with sodium cholate. These data indicate that AEBS is an integral membrane component of the rough microsomal fraction of rat liver.  相似文献   
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Enzymic hydrolysis of colanic acid   总被引:2,自引:0,他引:2  
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OBJECTIVE--To review treatment with pulsatile luteinising hormone releasing hormone in infertile women who do not ovulate and are resistant to clomiphene after 100 pregnancies achieved with this treatment. DESIGN--Retrospective analysis of 146 courses of treatment over 434 cycles. SETTING--Infertility clinic. PATIENTS--118 Women whose failure to ovulate was due to idiopathic hypogonadotrophic hypogonadism (n = 39), amenorrhoea related to low weight (n = 17), organic pituitary disease (n = 15), or polycystic ovaries (n = 47). INTERVENTIONS--Dose of 15 micrograms luteinising hormone releasing hormone/pulse subcutaneously every 90 minutes given with a miniaturised pump throughout cycle monitored by ultrasound. Women with hypogonadotrophic hypogonadism had 48 courses, women with amenorrhoea related to low weight 23, women with organic pituitary disease 18, and women with polycystic ovaries 57. END POINT--Follow up of 100 pregnancies achieved in 77 women during six years after introducing treatment. MEASUREMENTS and main results--One hundred pregnancies (seven multiple, 28 miscarriages). Cumulative rates of pregnancy were 93-100% at six months in women with idiopathic hypogonadotrophic hypogonadism, amenorrhoea related to low weight, and organic pituitary disease. In women with polycystic ovaries (cumulative rate of pregnancy 74%) adverse prognostic factors were obesity, hyperandrogenism, and high luteinising hormone concentrations, which were also associated with a high rate of early pregnancy loss. CONCLUSIONS--Treatment with pulsatile luteinising hormone releasing hormone is safe, simple, and effective, and the preferred method of inducing ovulation in appropriately selected patients. Compared with exogenous gonadotrophin treatment there is little need for monitoring, no danger of hyperstimulation, and a low rate of multiple pregnancies.  相似文献   
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