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31.
32.
W Guo RS Lovell YH Zhang BL Huang TP Burris WJ Craigen ER McCabe 《Canadian Metallurgical Quarterly》1996,178(1-2):31-34
We cloned the murine full-length cDNA encoding Ahch, the mouse homologue of DAX1 (DSS-AHC Region on Human X Chromosome, Gene1) which is the gene responsible for human X-linked adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH). Sequence analysis revealed that the murine and human cDNAs have 65% aa identity and 75% aa similarity overall. The cysteine residues in the putative DNA binding domain, which may interact with Zn2+ ions to form zinc fingers, are 100% conserved between the two species, indicating that the novel zinc-finger structures in DAX1 may be functional. In addition, mouse interspecific backcrosses show that the Ahch gene is closely linked to the glycerol kinase locus, GyK, on the mouse X chromosome, indicating that the order of the loci is conserved in this syntenic region between mouse and human. 相似文献
33.
CB McCoy SA Smith LR Metsch RS Anwyl R Correa L Bankston JJ Zavertnik 《Canadian Metallurgical Quarterly》1994,2(4):267-274
Socioeconomic status is the most significant factor influencing the decreased survival associated with breast cancer in minority groups in the United States. Barriers to the use of early detection programs by low-income women often result in the detection of breast cancer at stages too advanced to assure optimum outcomes. In an effort to increase accessibility of breast cancer screening among such individuals, the Early Detection Program (EDP) was initiated in 1987. The program provided breast cancer screening to women 40 years of age and older who attended eight primary healthcare centers located in low-income neighborhoods throughout Dade County, Florida. From its inception in October 1987 through December 1993, 23,866 medically underserved women had mammography examinations, with more than 17,000 of these women undergoing baseline mammograms. Since the program's inception, 126 cancers were diagnosed in 123 women. A dramatic shift from later to earlier stage breast cancers was observed. These results warrant a greater inclusion of medically underserved and lower socioeconomic status women in screening programs for the early detection of breast cancer. 相似文献
34.
Bipolar illness may be characterized by dysregulation and dysfunction of biologically active ions and ion pumps, respectively. In an effort to examine whether purported physiologic abnormalities may have functional counterparts, nerve conduction velocities (NCVs) and H-reflex recovery were examined in 7 acutely manic, 11 euthymic bipolar, 13 remitted schizophrenic, and 6 normal control individuals. All electrophysiologic tests were clinically normal. However, euthymic bipolar patients had significantly slower NCVs than either manic or normal individuals. Percent decrement of H-reflex recovery was nonsignificantly increased in manic versus euthymic bipolar subjects. Data analysis suggests lithium was not responsible for these changes. These data indicate that different mood states in bipolar illness are associated with alterations in electroneurophysiologic function. 相似文献
35.
RS Rosomoff 《Canadian Metallurgical Quarterly》1996,12(3):171-173
Intravesical potassium sensitivity can readily elicit abnormal epithelial permeability responses in subjects with diseased bladder, primarily interstitial cystitis. The technique involves eliciting responses in each subject to 40 cc of plain water or 40 cc of potassium chloride solution (40 mEq per 100 cc water). The subjects are asked to rate their subjective responses 3-5 minutes after instillation of the test solution and told to compare the water and potassium. An abnormal provocation to potassium but not water is considered a positive response and a useful way to delineate people with epithelial dysfunction and loss of permeability control. On the other hand, normal subjects will not respond to either the water or potassium. 相似文献
36.
The biological consequences of O6-methylguanine (m6G) in DNA are well recognized. When template m6G is encountered by DNA polymerases, replication is hindered and trans-lesion replication results in the preferential incorporation of dTMP opposite template m6G. Thus, unrepaired m6G in DNA is both cytotoxic and mutagenic. Yet, cell lines tolerant to m6G in DNA have been isolated, which indicates that some cellular DNA polymerases may replicate m6G-containing DNA with reasonable efficiency. Previous reports suggested that mammalian pol beta could not replicate m6G-containing DNA, but we find that pol beta can catalyze trans-lesion replication; however, the lesion must reside in the optimal context for pol beta activity, single- or short nucleotide gapped substrates. Primed single-stranded DNA templates, with or without template m6G, were poor substrates for pol beta as reported in earlier studies. In contrast, trans-lesion replication by bacteriophage T4 DNA polymerase was observed for primed single-stranded DNA templates. Replication of m6G-containing DNA by T4 DNA polymerase required the gp45 accessory protein that clamps the polymerase to the DNA template. The rate-limiting step in replicating m6G-containing DNAs by both DNA polymerases tested was incorporation of dTMP across from the lesion. 相似文献
37.
We report the differences between using either EDTA plasma or serum in a turbidimetric assay for quantitation of C-reactive protein (CRP). A systematic discrepancy was found for these two sample materials. This was most pronounced in the low concentration range (below 20 mg1(-1)) at which lower values were found in serum than in EDTA plasma. Conversely, in the high concentration range, serum showed slightly higher values. Addition of K3-EDTA to the reaction buffer improved the kinetics for sera with low concentrations of CRP, thus increasing the sensitivity of the assay. We found an overall constant discrepancy of approximately 8% lower values in plasma than in serum (equally for low and high levels of CRP) after the addition of K3-EDTA. The most probable explanation for this effect seems to be the differing water content of serum and EDTA plasma. We discuss the role and function of EDTA in the CRP assay and suggest some hypothetical mechanisms. 相似文献
38.
Tuberous sclerosis (TSC) is an autosomal dominant syndrome that is linked to two genetic loci: TSC1 (9q34) and TSC2 (16p13). Brain manifestations such as cortical tubers and subependymal hamartoma/giant cell astrocytomas are major causes of TSC-related morbidity. In this study, we describe the central nervous system involvement in a unique rodent model of tuberous sclerosis. The Eker rat carries a spontaneous germline mutation of the TSC2 gene and is predisposed to multiple neoplasia. In a series of 45 adult Eker carriers (TSC2 +/-), three types of focal intracranial lesions were found, of which the subependymal and subcortical hamartomas were most prevalent (65%). There exist remarkable phenotypic similarities between the Eker rat and human subependymal lesions. Our study indicates that the predominant cellular phenotype of the subependymal hamartomas is astroglial and suggests that the neuronal contribution within these lesions is, in part, the result of pre-existing myelinated axons. The hamartomas did not show evidence of loss of the wild-type TSC2 allele; it remains to be determined whether TSC2 inactivation is necessary for their pathogenesis. This genetically-defined rodent model may be useful in elucidating the molecular and developmental basis of the subependymal giant cell astrocytoma in humans. 相似文献
39.
RS Wallis P Nsubuga C Whalen RD Mugerwa A Okwera D Oette JB Jackson JL Johnson JJ Ellner 《Canadian Metallurgical Quarterly》1996,174(4):727-733
Macrophage activation and tumor necrosis factor-alpha (TNF-alpha) production are critical in tuberculosis immunity but may result in increased human immunodeficiency virus (HIV) expression and accelerated HIV disease progression in HIV-infected persons. Pentoxifylline inhibits expression of TNF-alpha and HIV. A double-blind, placebo-controlled study of adjunctive therapy with pentoxifylline (1800 mg/day) as a timed-release formulation was done in Ugandan HIV-infected patients with pulmonary tuberculosis. Subjects had early HIV disease (mean CD4 cell count, 380/microL) and did not receive other antiretroviral drugs. Pentoxifylline resulted in decreased plasma HIV RNA and serum beta 2-microglobulin and, in a subset of moderately anemic patients, improved blood hemoglobin levels. Trends were noted toward reduced TNF-alpha production in vitro and improved performance scores, but these did not reach statistical significance. No effect was noted on body mass, CD4 cell count, or survival. Additional studies of more potent TNF-alpha inhibitors in HIV-positive subjects with tuberculosis are warranted. 相似文献
40.