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61.
MH West RE Barsley JE Hall S Hayne M Cimrmancic 《Canadian Metallurgical Quarterly》1992,37(6):1480-1488
This article is a discussion of the use of narrow-band light sources coupled with cameras equipped with band-pass filters to document patterned injuries on human skin. Several case reports are included. 相似文献
62.
We have isolated a putative serine/threonine receptor kinase gene with an expression pattern indicating that it may play a role in the stylar response to pollination. Differential display PCR was used to select tobacco mRNAs with increased accumulation following pollination. NTS16, a cDNA identified by this method, is homologous to a ca. 2.4 kb mRNA primarily expressed in pistil tissues. Levels of this mRNA increase during floral development and are further increased by pollination reaching maximal accumulation 12-18 hours after pollination and then declining. mRNA levels can also be increased by the application of ethylene to unpollinated flowers. A polypeptide encoded by the NTS 16 open reading frame has sequence similarity to the catalytic domain of several receptor protein kinases from plants including the S-receptor kinases implicated in the rejection of self-pollen in Brassica species and the Pto gene product of tomato which confers resistance to a bacterial pathogen. 相似文献
63.
LB Corbeil RP Gogolewski I Kacskovics KH Nielsen RR Corbeil JL Morrill R Greenwood JE Butler 《Canadian Metallurgical Quarterly》1997,61(3):207-213
AIMS/BACKGROUND: To characterise clinically a large kindred segregating retinitis pigmentosa and sensorineural hearing impairment in an autosomal dominant pattern and perform genetic linkage studies in this family. Extensive linkage analysis in this family had previously excluded the majority of loci shown to be involved in the aetiologies of RP, some other forms of inherited retinal degeneration, and inherited deafness. METHODS: Members of the family were subjected to detailed ophthalmic and audiological assessment. In addition, some family members underwent skeletal muscle biopsy, electromyography, and electrocardiography. Linkage analysis using anonymous microsatellite markers was performed on DNA samples from all living members of the pedigree. RESULTS: Patients in this kindred have a retinopathy typical of retinitis pigmentosa in addition to a hearing impairment. Those members of the pedigree examined demonstrated a subclinical myopathy, as evidence by abnormal skeletal muscle histology, electromyography, and electrocardiography. LOD scores of Zmax = 3.75 (theta = 0.10), Zmax = 3.41 (theta = 0.10), and Zmax = 3.25 (theta = 0.15) respectively were obtained with the markers D9S118, D9S121, and ASS, located on chromosome 9q34-qter, suggesting that the causative gene in this family may lie on the long arm (q) of chromosome 9. CONCLUSIONS: These data indicate that the gene responsible for the phenotype in this kindred is located on chromosome 9 q. These data, together with evidence that a murine deafness gene is located in a syntenic area of the mouse genome, should direct the research community to consider this area as a candidate region for retinopathy and/or deafness genes. 相似文献
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65.
Four genes on the short arm of human chromosome 19 (HSA 19p) were assigned to bovine chromosome 7 (BTA 7) using a bovine x rodent somatic hybrid cell panel. These four genes were cartilage oligomeric matrix protein (COMP), lymphoblastic leukemia derived sequence 1 (LYL1), lysosomal alpha-mannosidase (MANB), and RAS oncogene family member RAB3A. Bovine sequence tagged sites were developed for the four genes and used for screening a bovine x rodent somatic cell panel. All four genes were mapped to bovine synteny group U22 (BTA 7) with a correlation coefficient of 0.901-1.000. This study confirms that the centromeric region of BTA 7 is conserved with HSA 19p. 相似文献
66.
67.
RP Dullaart K Hoogenberg SC Riemens JE Groener A van Tol WJ Sluiter BK Stulp 《Canadian Metallurgical Quarterly》1997,46(12):2082-2087
The TaqIB cholesteryl ester transfer protein (CETP) gene polymorphism (B1B2) is a determinant of HDL cholesterol in nondiabetic populations. Remarkably, this gene effect appears to be modified by environmental factors. We evaluated the effect of this polymorphism on HDL cholesterol levels and on the lipoprotein response to a linoleic acid-enriched, low-cholesterol diet in patients with type 1 diabetes. In 44 consecutive type 1 diabetic patients (35 men), CETP polymorphism, apolipoprotein (apo) E genotype, serum lipoproteins, serum CETP activity (measured with an exogenous substrate assay, n = 30), clinical variables, and a diet history were documented. The 1-year response to diet was assessed in 14 type 1 diabetic patients, including 6 B1B1 and 6 B1B2 individuals. HDL cholesterol was higher in 10 B2B2 than in 14 B1B1 homozygotes (1.63 +/- 0.38 vs. 1.24 +/- 0.23 mmol/l, P < 0.01). HDL cholesterol, adjusted for triglycerides and smoking, was 0.19 mmol/l higher for each B2 allele present. CETP activity levels were not significantly different between CETP genotypes. Multiple regression analysis showed that VLDL + LDL cholesterol was associated with dietary polyunsaturated:saturated fatty acids ratio (P < 0.02) and total fat intake (P < 0.05) in the B1B1 homozygotes only and tended to be related to the presence of the apo E4 allele (P < 0.10). In response to diet, VLDL + LDL cholesterol fell (P < 0.05) and HDL cholesterol remained unchanged in 6 B1B1 homozygotes. In contrast, VLDL + LDL cholesterol was unaltered and HDL cholesterol decreased (P < 0.05) in 6 B1B2 heterozygotes (P < 0.05 for difference in change in VLDL + LDL/HDL cholesterol ratio). This difference in response was unrelated to the apo E genotype. Thus, the TaqIB CETP gene polymorphism is a strong determinant of HDL cholesterol in type 1 diabetes. This gene effect is unlikely to be explained by a major influence on the serum level of CETP activity, as an indirect measure of CETP mass. Our preliminary data suggest that this polymorphism may be a marker of the lipoprotein response to dietary intervention. 相似文献
68.
The Drosophila developmental mutation quartet causes late larval lethality and small imaginal discs and, when expressed in the adult female, has a lethal effect on early embryogenesis. These developmental defects are associated with mitotic defects, which include a low mitotic index in larval brains and incomplete separation of chromosomes in mitosis in the early embryo. quartet mutations also have a biochemical effect, i.e., a basic shift in isoelectric point in three proteins. We have purified one of these proteins, raised an antibody to it, and isolated and sequenced its cDNA. At the amino acid level, the sequence shows 68% identity and 81% similarity to bovine smg p25a GDP dissociation inhibitor (GDI), a regulator of ras-like small GTPases of the rab/SEC4/YPT1 subfamily. The correlation between a basic shift in isoelectric point in Drosophila GDI in quartet mutant tissue and the quartet developmental phenotype raises the possibility that a posttranslational modification of GDI is necessary for its function and that GDI function is essential for development. 相似文献
69.
70.
S Sawaguchi BY Yue JE Kawa IL Chang SS Twining B Meberg 《Canadian Metallurgical Quarterly》1994,35(1):251-261
PURPOSE: To examine in the human trabecular meshwork lysosomal enzymes and one inhibitor of serine proteases that actively participate in the degradation of macromolecules into low molecular weight constituents. METHODS: Using an avidin-biotin-peroxidase technique, lysosomal proteases and alpha 1-proteinase inhibitor were examined in the trabecular meshwork of 23 human eyes with donor ages ranging from 2 to 90 years. These eyes were categorized into three age groups (< or = 20, 21 to 49, and > or = 50 years). Histochemical staining for lysosomal hydrolases was also performed on frozen sections of 20 human eyes. The staining was analyzed by an image analyzer and the levels of lysosomal proteases were further measured by biochemical assays. RESULTS: The trabecular meshwork from all the eyes stained intensely against antibodies to cathepsins B and G and alpha 1-proteinase inhibitor. The staining for elastase was weaker but evident. Image analyses revealed that the staining intensity for each protease or inhibitor was similar in all age groups. The staining in the uveal meshwork appeared to be the strongest among all the trabecular meshwork regions. Biochemical assays of tissue extracts confirmed that the enzyme and inhibitor levels were comparable among the three donor age groups. Activities of two lysosomal hydrolases, acid phosphatase and acid esterase, were also found in trabecular meshwork cells of 20 eyes. No apparent difference in enzyme activities was found with increasing age, and variation related to region was not observed. CONCLUSIONS: This study demonstrated the age-independent distribution of a variety of lysosomal enzymes and a protease inhibitor in the human trabecular meshwork. The presence of these proteins suggests a possible role in the metabolic operation of the trabecular meshwork. 相似文献