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81.
Diagnosis of X-chromosomal microdeletions has relied upon the traditional methods of Southern blotting and DNA amplification, with carrier identification requiring timeconsuming and unreliable dosage calculations. In this report, we describe rapid molecular cytogenetic identification of deleted DNA in affected males with the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency, CGKD) and female carriers for this disorder. CGKD deletions involve the genes for glycerol kinase, Duchenne muscular dystrophy, and/or adrenal hypoplasia congenita. We report an improved method for diagnosis of deletions in individuals with CGKD and for identification of female carriers within their families, using fluorescence in situ hybridization (FISH) with a cosmid marker (cosmid 35) within the glycerol kinase gene. When used in combination with an Xq control probe, affected males demonstrate a single signal from the control probe, while female carriers demonstrate a normal chromosome with two signals, as well as a deleted chromosome with a single signal from the control probe. FISH analysis for CGKD provides the advantages of speed and accuracy for evaluation of submicroscopic X-chromosomal deletions, particularly in identification of female carriers. In addition to improving carrier evaluation, FISH will make prenatal diagnosis of CGKD more readily available. © 1995 Wiley-Liss, Inc.  相似文献   
82.
Selective hyperthermia can be a feasible treatment modality for deep tissue abnormalities. It is accomplished by using a laser or ultrasound noninvasively to transfer energy to a desired target causing tissue damage. This process has two potential benefits to medical professionals: simplicity of procedure and safety to patient. However, optimizing these selective interactions is difficult due to the number of variables. We propose an optimization coefficient relating the dynamic and geometric parameters of selective hyperthermia, and proceed to measure it in an experimental setup consisting of a near-infrared laser and laser-absorbing dye. To simulate tissue, gelatin phantoms are created using a combination of water, intralipid, and gelatin. Our experiments use a 1.00-cm-diam spherical phantom that is homogeneously enhanced with an indocyanine green (ICG) solution and placed inside a nontarget phantom and irradiated by an 805-nm diode laser. Temperature measurements taken at different locations are analyzed so optimization coefficients can be calculated for different parameters. This optimization coefficient compares the difference in temperatures from inside and outside the target. Analysis of the values after thermal equilibrium provides information about the best parameter selection. Our findings indicate that the optimal ICG concentration and power combination for our tested parameters are 0.083% and 0.97 W, respectively. Based on our analysis, optimization can be obtained by using this coefficient to compare the selectivity of several parameter combinations.  相似文献   
83.
Summary The Escherichia coli aspartase gene aspA has been expressed in the fungus Aspergillus nidulans using the powerful constitutive gpdA promoter and trpC terminator, both from A. nidulans. Multiple, but not single, copies of aspA overcome nutritional deficiencies resulting from the loss of catabolic NAD-linked glutamate dehydrogenase. They also circumvent certain nutritional deficiencies resulting from loss of the positive-acting regulatory gene product mediating nitrogen metabolite repression. Both of these cases of physiological suppression involve the aspartase-catalyzed catabolism of aspartate to ammonium plus fumarate. No physiological evidence for the opposite reaction leading to aspartate synthesis was obtained as multiple copies of aspA did not affect the phenotype resulting from the loss of anabolic NADP-linked glutamate dehydrogenase. The use of vectors containing aspA and recipients lacking NAD-linked glutamate dehydrogenase is an efficient means of selecting multicopy transformants in A. nidulans and also offers the possibility to select strains having increased aspartase levels from original transformants.  相似文献   
84.
Cell exfoliation in the gut is an important cell renewal mechanism. To approach its investigation we applied a novel immunomagnetic technique for isolation of exfoliated cells from human stool. Exfoliated colonocytes were isolated from 168 stool samples. The cells were assessed microscopically using conventional stains and immunohistochemistry. The technique allowed us to obtain well-preserved colonocytes displaying characteristic features of well-differentiated colonic epithelium and positive immunostaining for cytokeratin 5/8. No mucin-producing cells were found. Exfoliated cells did not produce inducible nitric oxide synthase, albeit cultured colon carcinoma cells HT-29 analysed in parallel showed strong immunostaining. Analysis of exfoliated cell numbers in consecutive stool samples from the same subjects revealed considerable interindividual variation. Overall exfoliated colonocyte numbers were relatively low, isolation being unaffected by addition during the procedure of excessive amounts of HT-29 cells. Apoptosis was extremely rare among exfoliated colonocytes. Well-preserved exfoliated colonocytes can be consistently isolated from human faeces using a simple procedure. Our findings suggest that the actual process of cell exfoliation in the human colon may be much less intense than is generally accepted. Exfoliated cell isolation from human stool constitutes a convenient non-invasive approach that can be used for diagnostic and research purposes.  相似文献   
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Breast cancer and early detection of the disease is a significant issue for all women. Moreover, the sociocultural implications in the differential mortality rates increased interest in possible barriers to screening practices. Recently, a number of studies have investigated African Americans' cultural beliefs associated with breast cancer. This study is based upon qualitative focus group data gathered from 1989 to 1991 and 1996. This article provides focus group data that informed a culturally competent community-based cancer education program for African-American women--the Witness Project. Analysis of the qualitative data along with the quantitative outcome data revealed a direct relationship between cultural beliefs and patterns with mammography utilization. The once perceived cultural barriers can actually be applied as a cultural intervention strategy to improve breast cancer screening initiatives designed specifically for African-American women.  相似文献   
87.
Short-term exploratory activity was found to be significantly higher in C57BL/6By than in BALB/cBy inbred mice. Scopolamine reversed the activity levels in these strains. Basal exploratory activity levels and the effects of scopolamine on this behavioral measure assessed in these two strains, their reciprocal F1 hybrids, their recombinant inbred strains and three C57BL/6 congenic lines permitted characterization of a gene exerting a major effect on short-term exploratory activity [Exa, linked to H(w26), chromosome 4 (LG VIII)] and of a gene modulating the effects of scopolamine in this behavior, [Sco, linked to H-2, chromosome 17 (LG IX)]. Amphetamine exerted opposite effects in relation to those exerted by scopolamine on activity and its action was found to be determined by a polygenic system.  相似文献   
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Properties of a filamentous virus of the honey bee (Apis mellifera)   总被引:2,自引:0,他引:2  
An ellipsoidal particle, measuring 450 x 150 nm, from honey bees comprises a nucleocapsid measuring 3000 x 40 nm, containing double-stranded DNA with a molecular weight of approximately 12 x 10(6), which is coiled within a membrane. The buoyant densities in CsCl of the whole particle, nucleocapsid, DNA and DNA with ethidium bromide are 1.28, 1.36, 1.71 and 1.61 g/ml, respectively. The particle contains about 12 proteins, with molecular weights ranging from 13,000 to 70,000, which are distributed approximately equally between the membrane and the nucleocapsid.  相似文献   
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