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1.
Two South African Pyrgomorpha species have reduced chromosome numbers, due to centric fusions between the largest autosomes and the medium and small autosomes. P. rugosa has 2n=11(XO) (4 pairs of submetacentric and 1 pair of acrocentric autosomes) and P. granulata has 2n=13(XO) (3 pairs of submetacentric and 3 pairs of acrocentric autosomes). A third South African species has a typical Pyrgomorphidae number of 2n=19(XO) (acrocentrics). The mean chiasma frequency of the 2n=19 species is higher than that of the other two, although the frequencies of distal chiasmata in all three are similar. The recombination potential of the two species with lower chromosome numbers has been reduced, due to fewer crossovers in comparison to the 2n=19 species, as well as to independent assortment.  相似文献   
2.
On aligning the tryptic peptides of the myoglobin from a gorilla with the homologous human peptides, one amino acid difference was found. By dansyl-Edman degradation this was shown to be at position 22, i.e. at a position other than those where man, chimpanzee and gibbon differ from one another.  相似文献   
3.
We have previously reported the synthesis and evaluation of potent anti-human immunodeficiency virus compounds based on β-D-d4T analogues bearing a tether attached at the C-5 position and their β-L-counterparts. Initial study revealed a requirement for an alkyl side-chain with an optimal length of 12 carbons for a weak antiviral activity. As a continuation of that work, we have now prepared the corresponding phosphoramidate derivatives as possible membrane-permeable prodrugs. Phosphorochloridate chemistry gave the target phosphoramidates which were tested for anti-human immunodeficiency virus type 1 activity; unfortunately, they were devoid of anti-HIV activity.  相似文献   
4.
Several recent genetic studies have suggested linkage of Type 2 diabetes (non-insulin-dependent diabetes mellitus) susceptibility to a region of chromosome 20q12-q13.1. To facilitate the identification and cloning of a diabetes susceptibility gene(s) in this region, we have constructed correlated radiation hybrid and YAC/BAC contig physical maps of the region. A high-resolution radiation hybrid map encompassing 9.5 Mb between the PLC and the CEBPB genes was constructed using 68 markers: 25 polymorphic markers, 15 known genes, 21 ESTs, and 7 random genomic sequences. The physical order of the polymorphic markers within this radiation hybrid map is consistent with published genetic maps. A YAC/BAC contig that gives continuous coverage between PLC and CEBPB was also constructed. This contig was constructed from 24 YACs, 34 BACs, and 1 P1 phage clone onto which 71 markers were mapped: 23 polymorphic markers, 12 genes, 24 ESTs, and 12 random genomic sequences. The radiation hybrid map and YAC/BAC physical map enable precise mapping of newly identified transcribed sequences and polymorphic markers that will aid in linkage and linkage disequilibrium studies and facilitate identification and cloning of candidate Type 2 diabetes susceptibility genes residing in 20q12-q13.1.  相似文献   
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A simple three-component chiral derivatization protocol for determining the enantiopurity of chiral primary amines by 1H NMR spectroscopic analysis is described here. The method involves condensation of the amines with 2-formylphenylboronic acid and enantiopure 1,1'-bi-2-naphthol. This approach affords a mixture of diastereoisomeric iminoboronate esters whose ratio can be determined by the integration of well-resolved diastereotopic resonances in their 1H NMR spectra, thus enabling the enantiopurity of the parent amine to be determined easily. The protocol, as described, takes less than 90 min to complete.  相似文献   
7.
Acute services for mental health crises are very important to service users and their supporters, and consume a substantial share of mental health resources in many countries. However, acute care is often unpopular and sometimes coercive, and the evidence on which models are best for patient experience and outcomes remains surprisingly limited, in part reflecting challenges in conducting studies with people in crisis. Evidence on best ap­proaches to initial assessment and immediate management is particularly lacking, but some innovative models involving extended assessment, brief interventions, and diversifying settings and strategies for providing support are potentially helpful. Acute wards continue to be central in the intensive treatment phase following a crisis, but new approaches need to be developed, evaluated and implemented to reducing coercion, addressing trauma, diversifying treatments and the inpatient workforce, and making decision‐making and care collaborative. Intensive home treatment services, acute day units, and community crisis services have supporting evidence in diverting some service users from hospital admission: a greater understanding of how best to implement them in a wide range of contexts and what works best for which service users would be valuable. Approaches to crisis management in the voluntary sector are more flexible and informal: such services have potential to complement and provide valuable learning for statutory sector services, especially for groups who tend to be underserved or disengaged. Such approaches often involve staff with personal experience of mental health crises, who have important potential roles in improving quality of acute care across sectors. Large gaps exist in many low‐ and middle‐income countries, fuelled by poor access to quality mental health care. Responses need to build on a foundation of existing community responses and contextually relevant evidence. The necessity of moving outside formal systems in low‐resource settings may lead to wider learning from locally embedded strategies.  相似文献   
8.
ABSTRACT

Zone electrophoresis separations of human recombinant interleukin-3 (rh IL-3) and related proteins in untreated fused silica capillaries are presented. Results using pH 9 CHES buffer show that rh IL-3 is easily separated from a common carrier, human serum albumin, in a commercial preparation.  相似文献   
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The incorporation of the specialized carbohydrate affinity ligand methacrylamido phenylboronic acid in polyacrylamide gels for SDS‐PAGE analysis has been successful for the separation of carbohydrates and has here been adapted for the analysis of post‐translationally modified proteins. While conventional SDS‐PAGE analysis cannot distinguish between glycated and unglycated proteins, methacrylamido phenylboronate acrylamide gel electrophoresis (mP‐AGE) in low loading shows dramatic retention of δ‐gluconolactone modified proteins, while the mobility of the unmodified proteins remains unchanged. With gels containing 1% methacrylamido phenylboronate, mP‐AGE analysis of gluconoylated recombinant protein Sbi results in the retention of the modified protein at a position expected for a protein that has quadrupled its expected molecular size. Subsequently, mP‐AGE was tested on HSA, a protein that is known to undergo glycation under physiological conditions. mP‐AGE could distinguish between various carbohydrate‐protein adducts, using in vitro glycated HSA, and discriminate early from late glycation states of the protein. Enzymatically glycosylated proteins show no altered retention in the phenylboronate‐incorporated gels, rendering this method highly selective for glycated proteins. We reveal that a trident interaction between phenylboronate and the Amadori cis 1,2 diol and amine group provides the molecular basis of this specificity. These results epitomize mP‐AGE as an important new proteomics tool for the detection, separation, visualization and identification of protein glycation. This method will aid the design of inhibitors of unwanted carbohydrate modifications in recombinant protein production, ageing, diabetes, cardiovascular diseases and Alzheimer's disease.  相似文献   
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