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本文报道消旋棉酚与15种不同结构的光学活性胺缩合产物的薄层色谱性质和核磁共振氢谱数据,以及8个光学活性胺与光学活性棉酚缩合物的光学稳定性,并探讨了结构与这些性质的关系。  相似文献   
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A 23-year-old Chinese man with dermatomyositis associated calcinosis cutis received electric shock wave lithotripsy (ESWL) as an alternate to a conventional pharmacological regimen to reduce pain associated with the complications of subcutaneous calcinosis nodules. He became symptom and opioid free after two courses of ESWL. No significant adverse effect had been noted. ESWL may serve as a means of pain killing in patients suffering from debilitating pain caused by complicated calcinosis cutis.  相似文献   
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High-density single-nucleotide polymorphism (SNP) genotyping technology enables extensive genotyping as well as the detection of increasingly smaller chromosomal aberrations. In this study, we assess molecular karyotyping as first-round analysis of patients with mental retardation and/or multiple congenital abnormalities (MR/MCA). We used different commercially available SNP array platforms, the Affymetrix GeneChip 262K NspI, the Genechip 238K StyI, the Illumina HumanHap 300 and HumanCNV 370 BeadChip, to detect copy number variants (CNVs) in 318 patients with unexplained MR/MCA. We found abnormalities in 22.6% of the patients, including six CNVs that overlap known microdeletion/duplication syndromes, eight CNVs that overlap recently described syndromes, 63 potentially pathogenic CNVs (in 52 patients), four large segments of homozygosity and two mosaic trisomies for an entire chromosome. This study shows that high-density SNP array analysis reveals a much higher diagnostic yield as that of conventional karyotyping. SNP arrays have the potential to detect CNVs, mosaics, uniparental disomies and loss of heterozygosity in one experiment. We, therefore, propose a novel diagnostic approach to all MR/MCA patients by first analyzing every patient with an SNP array instead of conventional karyotyping.  相似文献   
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Williams syndrome (WS) is a developmental disorder with a characteristic personality and cognitive profile that is associated, in most cases, with a 2 Mb deletion of part of chromosome band 7q11.23. By applying CpG island cloning methods to cosmids from the deletion region, we have identified a new gene, called FZD3. Dosage blotting of DNA from 11 WS probands confirmed that it is located within the commonly deleted region. Sequence comparisons revealed that FZD3, encoding a 591 amino acid protein, is a novel member of a seven transmembrane domain receptor family that are mammalian homologs of the Drosophila tissue polarity gene frizzled. FZD3 is expressed predominantly in brain, testis, eye, skeletal muscle and kidney. Recently, frizzled has been identified as the receptor for the wingless (wg) protein in Drosophila. We show that Drosophila as well as human cells, when transfected with FZD3 expression constructs, bind Wg protein. In mouse, the wg homologous Wnt1 gene is involved in early development of a large domain of the central nervous system encompassing much of the midbrain and rostral metencephalon. The potential function of FZD3 in transmitting a Wnt protein signal in the human brain and other tissues suggests that heterozygous deletion of the FZD3 gene could contribute to the WS phenotype.   相似文献   
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反相HPLC法测定六味安消胶囊及大黄药材中大黄素的含量   总被引:9,自引:0,他引:9  
目的:用反相HPLC法测定六味安消胶囊及大黄药材中大黄素的含量.方法:采用CLC-ODS C18色谱柱(5μm,4.6×150mm),流动相:甲醇-0.4%磷酸溶液(85∶15),检测波长:438nm,流速:1.2ml/min,柱温25℃.结果:大黄素的平均回收率为98.56%(RSD=2.61%,n=12),线性范围为0.0798~0.638μg(r=0.9999).结论:本法快速,准确,灵敏,简便易行.  相似文献   
46.
本文报道用中压柱色谱快速分离S或R-α-甲基苯乙胺及S或R-α-甲基苄胺缩(±)-棉酚的方法,可得光学活性胺缩( )或(一)-棉酚非对映体,经水解分别得到( )或(一)-棉酚。并证明胺缩光学活性棉酚非对映体之间有互相转化的性质,此特性可利用于棉酚对映体的转化。  相似文献   
47.
BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up.  相似文献   
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