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51.
A simple and rapid method for the simultaneous determination of 11 metals (As, Be, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in urine by inductively coupled argon plasma-atomic emission spectrometry is presented. Acidification of the urine was the only sample preparation required. Background correction was applied to ensure accuracy. Analytical calibration was based on matrix matching using a "simulated urine" solution. Detection limits in the low mg/L range and linearity over three orders of magnitude were obtained for all 11 metals. In the Occupational Health Laboratory, this procedure has been applied for routine screening of workers for occupational exposure to toxic metals. 相似文献
52.
Faravelli C Abrardi L Bartolozzi D Cecchi C Cosci F D'Adamo D Lo Iacono B Ravaldi C Scarpato MA Truglia E Rossi Prodi PM Rosi S 《Psychotherapy and psychosomatics》2004,73(4):226-234
BACKGROUND: It has been argued that lay interviewers' use of fully-structured interviews could lead to a diagnostic pattern different to that by treating physicians. Clinical interviewers in community samples should probably identify cases that are closer to those seen in clinical settings. The greatest advantage of using clinical interviewers consists of the immediate assessment of a possible psychopathology, i.e. the evaluation of current disorders. METHODS: Two thousand three hundred and sixty-three citizens from the community of Sesto Fiorentino, Italy, were interviewed by their own general practitioners using the Mini International Neuropsychiatric Interview (MINI). Positive cases for any lifetime psychiatric disorder as well as a random sample of the negative cases were re-interviewed by psychiatrists or trained residents in psychiatry using the Florence Psychiatric Interview (FPI). RESULTS: The point prevalence for any current disorder was 8.7%; the two disorders with the highest prevalence were generalised anxiety disorder (2.9%) and major depressive episode (2.7%). The figures increase about 50% when the sub-threshold sequelae of previous disorders are considered. Current comorbidity was generally high. The one-year prevalence of any disorder was 10.6%. Ninety-two percent of the cases sought help, 82% were being treated at the moment of interview. Social impairment was considerable. CONCLUSIONS: The period prevalence rates for most of the disorders considered were generally comparable with the range defined by previous studies conducted in other Western countries, despite using different methodologies. Conversely, the use of health facilities, the treatment received and the social impairment were much higher than those reported by the other studies, suggesting a greater similarity with the clinical samples. 相似文献
53.
Demonstration of an antigen common to several varieties of neoplasia 总被引:21,自引:0,他引:21
54.
Dr. David Lo Christina R. Reilly Linda C. Burkly Jenefer DeKoning Terri M. Laufer Laurie H. Glimcher 《Immunologic research》1997,16(1):3-14
Ten years ago, we proposed a model for thymus function in which thymic epithelial cells are primarily responsible for imprinting
major histocompatibility complex (MHC)-restricted specificity, and bone marrow-derived macrophages or dendritic cells are
responsible for the induction of self-tolerance. Since then, transgenic and knockout models have allowed for a dissection
of thymic stromal components in vivo, leading to a new understanding of their specialized functions. We have determined that
with regard to class II-restricted CD4 T-cell development, two distinct subsets of thymic epithelium help shape the repertoire:
Cortical epithelium appears solely responsible for positive selection, whereas a fucose-bearing subset of medullary epithelium
is specialized for negative selection. This absolute separation of positive and negative selection into two distinct spatial
and temporal compartments leads to a much simpler view of the process of repertoire selection. Finally, a novel view of the
function of the thymic medulla is discussed. 相似文献
55.
Summary. Nested polymerase chain reaction (PCR) amplifying the morphological transforming region II (mtrII) of cytomegalovirus (CMV)
has been shown to be useful in the detection of CMV DNA in bone marrow transplant (BMT) recipients. However, there has never
been any report on mutation hot spots and subtypes of this open reading frame. Using primers derived from sequences upstream
and downstream of mtrII (ORF 79), CMV DNA from peripheral blood leukocytes (PBL) and conventional CMV culture of 16 BMT recipients
were amplified by PCR, cloned into pUC118, and sequenced. The amino acid sequences were predicted using the standard triplet
code. The DNA sequences obtained from direct amplification of CMV in PBL obtained from the 16 patients were 100% identical
to the corresponding ones obtained by amplification of CMV DNA extracted from conventional CMV culture. Within mtrII (ORF
79), hot spot single base mutations were observed at positions +40 (G→A), +123 (A→G), +213 (T→C), and +219 (T→C). However,
because of third base degeneracy, only amino acid 14 was changed from valine to isoleucine in the predicted protein of 13
patients. This corresponded to the hot spot mutation at position +40 (GTC→ATC), while the rest were silent mutations. An insertion
of 3 bases (ACG) was observed in the CMV DNA of 10 patients at positions +91 to +93, leading to a threonine insertion at amino
acid 31 in these patients. For patient no. 147 there was a 65 bp deletion in the CMV DNA amplified later in the course of
BMT as compared with that early in the course. This gave rise to a frame shift mutation and a change of more than 70% in the
predicted amino acid sequence of the protein.
Accepted October 14, 1998 Received May 20, 1998 相似文献
56.
Increased expression of osteopontin gene in atypical teratoid/rhabdoid tumor of the central nervous system. 总被引:4,自引:0,他引:4
Chung-Lan Kao Shih-Hwa Chiou Yann-Jang Chen Sher Singh Han-Tso Lin Ren-Shyan Liu Chih-Wen Lo Chi-Chang Yang Chin-Wen Chi Chen-hsen Lee Tai-Tong Wong 《Modern pathology》2005,18(6):769-778
The atypical teratoid/rhabdoid tumor, primary to the central nervous system, is a highly malignant and aggressive neoplasm of infancy and childhood. Although having distinct biological features and clinical outcomes, it is frequently misdiagnosed as primitive neuroectodermal tumor/medulloblastoma. To further distinguish the underlying pathogenesis and to identify biological markers for clinical use, an atypical teratoid/rhabdoid tumor-derived cell line was established and its gene expression pattern analyzed in comparison to the human astrocyte SVG12 cell line and the human DAOY medulloblastoma cell line using a complementary DNA microarray method. The osteopontin gene was found specifically upregulated in atypical teratoid/rhabdoid tumor cells. This specificity was confirmed by immunohistochemistry in pathological sections of tissues from atypical teratoid/rhabdoid tumor patients. Even though the role of osteopontin in the cytopathogenesis of atypical teratoid/rhabdoid tumor still needs to be determined, our data support that overexpressed osteopontin is a potential diagnostic marker for atypical teratoid/rhabdoid tumor. 相似文献
57.
Overexpression of connexin43 alters the mutant phenotype of midgestational wnt-1 null mice resulting in recovery of the midbrain and cerebellum 总被引:1,自引:0,他引:1
Melloy PG Kusnierczyk MK Meyer RA Lo CW Desmond ME 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,283(1):224-238
The midbrain-hindbrain (MHB) junction plays a key role in the patterning of the embryonic neural tube and the formation of brain structures such as the cerebellum. The mitogen wnt-1 is critical for cerebellar development, as evidenced by the lack of MHB region and cerebellar formation in the wnt-1 null embryo. We have generated wnt-1 null embryos overexpressing the gap junction gene connexin43 by crossing wnt-1 null heterozygotes into the CMV43 mouse line. We have confirmed that these mice show an increase in gap junctional communication by dye coupling analysis. Two-thirds of wnt-1 null CMV43(+) mouse embryos at E18.5 have a cerebellum. In addition, changes in the wnt-1 null phenotype in mouse embryos overexpressing connexin43 are observed as early as E9.5. At this stage, one-quarter of wnt-1 null CMV43(+) embryos display extra or expanded tissue present at the MHB boundary (a wnt-1 null enlarged phenotype). In situ hybridization studies conducted on these embryos have indicated no changes in the expression of embryonic brain positional markers in this region. We conclude from these studies that overexpression of the connexin43 gap junction restores cerebellar formation by compensating for the loss of wnt-1. 相似文献
58.
R C Porter P Lo D E Low A E Simor A McGeer S Scriver T C Moore C Goldman M Skulnick 《Journal of clinical microbiology》1993,31(10):2794-2795
The BACTEC PLUS 26 (NR26) (Becton Dickinson, Towson, Md.) high-volume blood culture bottle replaced the less expensive smaller-volume NR6A bottle in our hospital. An audit carried out several months after their introduction revealed that only 17.5% of the NR26 bottles received the required blood volume. Several audits and educational programs were required in order to achieve a compliance rate of > 60%. 相似文献
59.
AIM: Development of a specific polymerase chain reaction (PCR) assay for detection of the pre-core, stop codon, mutant of hepatitis B virus (HBV). METHODS: PCR primers, specific at the 3'-end for nucleotide 1896 of either the pre-core, stop codon, mutant or wild type HBV, were synthesised using published sequence data. Positive control templates for both types of virus were synthesised by the PCR, incorporating sequences specific for each virus type at the appropriate position. These templates were used to optimise the specificity of the procedure. Formalin fixed, paraffin wax embedded human tissue from acute or fulminant HBV hepatitis from Hong Kong or Oxford was then investigated for presence of mutant or wild type virus. The HBV DNA was amplified from this tissue using a two step procedure, with an initial amplification phase followed by a second diagnostic phase on optimally diluted target DNA. RESULTS: Specific detection of mutant or wild type HBV was achieved. An important factor in determining specificity was the temperature of annealing, 70 degrees C proving to be highly specific. To overcome the inherent variation of target copy number in clinical samples and to provide an intrinsic positive control, it was important to generate and standardise the amount of target HBV used for the specific PCR. Two cases of fulminant hepatitis and four cases of acute hepatitis from Hong Kong, and one case of fulminant hepatitis from Oxford, contained only wild type HBV, with no evidence of a mutant virus. CONCLUSION: This method can be applied to FFPE tissues. It is rapid, non-radioactive, and specific for the stop codon mutation at nucleotide 1896 of HBV. Preliminary investigation of a small number of cases of fulminant hepatitis from Oxford and Hong Kong showed only wild type virus. The result differs from results published from Japan and Israel. 相似文献