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导数光谱系数倍率法测定多组分体系感冒清胶囊中盐酸吗啉胍的含量 总被引:1,自引:0,他引:1
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12). 相似文献
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D A Strom R S Dean L S Wenck K J Ibe 《The International journal of neuroscience》1987,33(3-4):179-184
Evidence accumulating from a variety of methodological approaches suggests that unusual laterality is often a concomitant feature of emotional pathology. In the present study both torque and a multifaceted measure of laterality were examined with respect to personality variables measured by the 16 PF in a normal population. Interestingly, a pattern of emotionality for subjects with a more confused laterality was revealed in a normal population which is notably similar to reported aberrant personality factors and laterality in more pathological groups. The existence of a cohesive continuum of emotional expression in relation to confused laterality is suggested. In addition, both torque and the multifactored measure of laterality are critiqued as research measures and for their clinical potential. 相似文献
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Application of reflectance spectroscopy to the estimation of uric acid, urea and glucose: an evaluation of the Ames Seralyzer
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An original approach to the measurement of analytes in clinical chemistry has now become available, in which dry reagent strip technology is linked to measurement by reflectance spectroscopy. The present studies have evaluated the performance of the first of these test systems—for uric acid, urea and glucose, in serum—by comparison with conventional liquid chemistry methods. Satisfactory performance in terms of both precision and accuracy was obtained for all three test systems, the current “state-of-the-art” performance criteria being met; the Seralyzer system proved reliable and easy to use in the hands of trained operators. It should find a place as a “Stat” analyser in the laboratory, in specified wards and in Health Centres. 相似文献
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Heath EM Morken NW Campbell KA Tkach D Boyd EA Strom DA 《Archives of pathology & laboratory medicine》2001,125(1):127-133
CONTEXT: To maximize the participation rate in population genetic studies, alternatives to invasive whole blood collection are increasing. One such alternative is buccal epithelial cell collection, which, in contrast to venipuncture and finger sticks, is painless. Buccal cells, if collected and purified efficiently, offer an acceptable source for DNA to be used in research and clinical applications. OBJECTIVE: To develop a noninvasive sampling method for collecting cells for routine DNA testing in a clinical laboratory setting. DESIGN: Five factors were used to evaluate several brands of mouthwash: (1) compatibility with the DNA purification chemistry, (2) DNA yield, (3) DNA quality, (4) DNA stability at room temperature, and (5) mouthwash taste. Next, an optimization study was undertaken to maximize DNA yield. Finally, a validation study was undertaken with the optimized protocol to test a panel of 14 donors for DNA yield and performance and to test for the stability of DNA held in mouthwash. SETTING: Industrial research and development laboratory. RESULTS: Of 5 mouthwashes tested, Scope brand mouthwash received the highest overall ranking. The addition of proteinase K and glycogen to the protocol significantly enhanced DNA yields, with a test panel (n = 14) giving a range of 12 to 60 microg of DNA per donor. In a 4-week room temperature stability study, the DNA in mouthwash samples was found to be stable for at least 2 weeks. CONCLUSION: A clinically validated DNA purification chemistry was adapted to a noninvasive specimen collection method. This method used a commercially available mouthwash, Scope, to collect buccal epithelial cells for the preparation of high-quality DNA in high yield. 相似文献
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Kermit Zhang Eleina Cox Samuel Strom Zhuo Luan Xu Alexis Disilvestro Kelly Usrey 《American journal of medical genetics. Part A》2020,182(9):2124-2128
Baraitser‐Winter cerebrofrontofacial syndrome (BWCFF) is a rare autosomal dominant developmental disorder associated with missense mutations in the genes ACTB or ACTG1. The classic presentation of BWCFF is discerned by the combination of unique craniofacial characteristics including ocular coloboma, intellectual disability, and hypertelorism. Congenital contractures and organ malformations are often present, including structural defects in the brain, heart, renal, and musculoskeletal system. However, there is limited documentation regarding its prenatal presentation that may encourage healthcare providers to be aware of this disorder when presented throughout pregnancy. Herein we describe a case of a pregnancy with large cystic hygroma and omphalocele. Whole exome sequencing (WES) was performed and a de novo, heterozygous, likely pathogenic mutation in ACTB was detected, c.1004G>A (p.Arg335His), conferring a diagnosis of BWCFF. 相似文献
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The epidermal growth factor receptor (EGFr) is a membrane-bound glycoprotein that is present in a wide variety of human normal and malignant tissues. In this study EGFr expression in frozen sections of prostate tissue obtained from 40 different surgical specimens was examined immunohistochemically with a well-characterized monoclonal antibody to EGFr, Ab-1 (Oncogene Science). Twenty cases of prostate adenocarcinoma and 20 cases of benign prostatic hyperplasia were studied. Six of the 20 cases of adenocarcinoma also contained prostatic intraepithelial neoplasia grade III (severe intraductal dysplasia). All of the cases containing benign glands showed strong immunostaining in a continuous or nearly continuous pattern, with staining restricted to the basal layer of the benign glands. Adenocarcinoma lacked immunostaining in 15 (75%) of 20 cases, while the remaining five cases (25%) showed diffuse cytoplasmic staining, which was weaker than that seen in the benign glands and that lacked basal accentuation. The six cases that contained prostatic intraepithelial neoplasia grade III showed a discontinuous basal pattern of staining, and the gaps in the staining appeared to correspond to areas of disruption of the basal cell layer. We conclude that the antigenic determinant recognized by this antibody to EGFr was detected preferentially in the basal layer in benign prostatic glands. In contrast, a minority of cases of adenocarcinoma expressed EGFr, as assessed by immunoreactivity with the Ab-1 monoclonal antibody. Prostatic intraepithelial neoplasia grade III expressed EGFr with a predominantly discontinuous basal pattern that corresponded to the disrupted basal cell layer typical of this process. 相似文献
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Autoimmune MRL-lpr have an abnormal pattern of lymphokine production. In our attempt to repair this defect, MRL-lpr mice were prophylactically treated daily with a lectin stimulated rat spleen cell product rich in interleukin-2. Therapy inhibited the lymphoid hyperplasia of the unique lymphocytes regulated by the lpr gene, suppressed the enhanced supranormal expression of Ia on peritoneal macrophages and protected this strain from autoimmune renal injury. Purified recombinant interleukin-2 alone did not prevent autoimmune disease expression. Thus, a spleen cell product other than interleukin-2 can ameliorate the aggressive course of lymphoproliferation and autoimmunity in MRL-lpr mice. 相似文献