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1.
2.
Controversy exists about the value of ultrasonography of meniscal tears. We therefore examined 101 knee joints of 99 patients in a prospective study. Prior to the arthroscopy the menisci were scanned from an independent team by using 7.5 and 10.0 MHz ultrasound waves. 81 meniscal tears were seen at arthroscopy; 36% of these tears could not be detected with the scanner (? false negative results) while 20% of intact menisci showed positive echogenic structures, which were analysed as meniscal tears. It seems that ultrasonography of the menisci is still of experimental use without any clinical importance. 相似文献
3.
Lisa A Peterson Meredith E Cummings Choua C Vu Brock A Matter 《Drug metabolism and disposition》2005,33(10):1453-1458
Furan is a liver carcinogen and toxicant. Furan is oxidized to the reactive dialdehyde, cis-2-butene-1,4-dial, by microsomal enzymes. This reactive metabolite readily reacts with glutathione nonenzymatically to form conjugates. A high-performance liquid chromatography-electrochemical method for the detection of cis-2-butene-1,4-dial-glutathione (GSH) conjugates in microsomal preparations was developed to measure the extent of furan metabolism to cis-2-butene-1,4-dial in vitro. Previously unobserved mono-GSH reaction products of cis-2-butene-1,4-dial were detected in addition to the already characterized bis-GSH conjugates. Chemical characterization of these compounds indicated that the alpha-amino group of glutathione had reacted with cis-2-butene-1,4-dial to form a thiol-substituted pyrrole adduct. The analytical method was used to estimate the extent of furan oxidation in rat liver microsomes from untreated or acetone-pretreated F344 rats as well as in human P450 2E1 Supersomes. Our results confirm that cytochrome P450 2E1 can catalyze the oxidation of furan to cis-2-butene-1,4-dial. However, the data are also consistent with the involvement of other P450 enzymes in the oxidation of furan in untreated animals. This assay will be a valuable tool to explore tissue and species differences in rates of furan oxidation. 相似文献
4.
Tobias von Lukowicz Michela Silacci Matthias T Wyss Eveline Trachsel Christine Lohmann Alfred Buck Thomas F Lüscher Dario Neri Christian M Matter 《Journal of nuclear medicine》2007,48(4):582-587
Targeting proteins that are overexpressed in atherosclerotic plaques may open novel diagnostic applications. The C domain of tenascin-C is absent from normal adult tissues but can be inserted during tumor progression or tissue repair into the molecule by alternative splicing. We tested the ability of the human antibody G11, specific to this antigen, to reveal murine atherosclerotic plaques ex vivo. The antibody directed against the extra domain B of fibronectin (L19) was used as a reference. METHODS: We intravenously injected (125)I-labeled G11 or L19 antibodies into apolipoprotein E-deficient (ApoE(-/-)) mice and harvested the aortae 4 or 24 h later. En face analyses of distal aortae and longitudinal sections of the aortic arch were performed to compare antibody uptake using autoradiography with plaque staining using oil red O. Plaque macrophages were detected by immunohistochemistry (anti-CD68 staining). Biodistribution of injected antibodies was investigated in aortae and blood at 4 and 24 h. RESULTS: En face analyses revealed a significant correlation between radiolabeled G11 and fat-stained areas, increasing from 4 to 24 h, with a correlation coefficient of 0.92 (P < 0.0001) and an average signal-to-noise ratio of 104:1 at 24 h. Plaque imaging using L19 showed similar results (r = 0.86; P < 0.0001; signal-to-noise ratio, 72:1 at 24 h). Uptake of radiolabeled antibodies in histologic sections colocalized with fat staining and activated macrophages in aortic plaques. Biodistribution analyses confirmed specific accumulation in aortic plaques as well as rapid blood pool clearance of the antibodies 24 h after injection. Immunofluorescence analyses revealed increased expression of tenascin and fibronectin isoforms in macrophage-rich plaques. CONCLUSION: The antibody G11, specific to the C domain of tenascin-C, visualizes murine atherosclerotic plaques ex vivo. In conjunction with the increased expression of the C domain of tenascin-C in macrophage-rich plaques, the colocalization of G11 uptake with activated macrophages, and the favorable target-to-blood ratio at 24 h, this antibody may be useful for molecular imaging of advanced atherosclerotic plaques in the intact organism. 相似文献
5.
Laparoscopic Cholecystectomy for Acute Cholecystitis: Prospective Trial 总被引:23,自引:0,他引:23
Samuel Eldar Edmond Sabo Ernest Nash Jack Abrahamson Ibrahim Matter 《World journal of surgery》1997,21(5):540-545
p
< 0.00001) and for hydrops (28.5%) and empyema of the gallbladder
(28.5%) (
p
= 0.004). The difference in conversion
between the group with acute necrotizing (gangrenous) cholecystitis and
the two groups with hydrops and empyema of the gallbladder was not
statistically significant (
p
= 0.07). The complication
rates of acute cholecystitis, hydrops, empyema of the gallbladder, and
gangrenous cholecystitis were 9.0%, 9.5%, 14.0%, and 20.0%,
respectively (
p
= NS). Patients with an operative
delay of 96 hours or less from the onset of acute cholecystitis had a
conversion rate of 23%, whereas a delay of more than 96 hours was
associated with a conversion rate of 47% (
p
= 0.022).
The complication rate was 8.5% in the laparoscopic group and 27% in
the converted group (
p
= 0.013). Patients over 65
years of age, with a history of biliary disease, a nonpalpable
gallbladder, WBC count over 13,000/cc, and acute gangrenous
cholecystitis were independently associated with a high LC conversion
rate; male patients, finding large bile stones, serum bilirubin over
0.8 mg/dl, and WBC count over 13,000/cc were independently associated
with a high complication rate following laparoscopic surgery with or
without conversion. Generally, LC can be performed safely for acute
cholecystitis, with acceptably low conversion and complication rates.
Different forms of cholecystitis carry various conversion and
complication rates in selected cases. LC for acute cholecystitis should
be performed within 96 hours of the onset of disease. Predictors of
conversion and complications may be helpful when planning the
laparoscopic approach to acute cholecystitis. 相似文献
6.
F. Berthold R. Berthold I. Matter M. Reither U. Rother F. Skvaril W.R. Willems 《Immunobiology》1982,162(1):46-55
Spleen exposure to ultrasound has been reported to influence antibody response to sheep red blood cell injection in mice (decreased hemagglutination and hemolytic titers and IgM, IgG2a and IgG2b levels and elevated IgG1 levels). In a controlled clinical trial, we investigated the possible immunosuppressive side-effect of splenic exposure (2.0 mW/m2, 3.5 MHz, 5 minutes) to ultrasound on the immune response to Rubella vaccination in 41 anti-Rubella antibody-negative volunteers. The measured parameters (blood cell count, IgA, IgM, IgG including subclasses IgG1-IgG4, isoagglutinins, anti-Rubella hemagglutinin and hemolysin titers, complement C3, skin tests to mumps and tuberculin, T, B and O lymphocytes, esterase-positive and negative T-cell subsets) suggest changes dependent on the time of vaccination, but provide no evidence of an immunosuppressive effect of ultrasound in man. 相似文献
7.
Blanton RE Salam EA Ehsan A King CH Goddard KA 《European journal of human genetics : EJHG》2005,13(5):660-668
A minority of individuals infected with the parasite Schistosoma mansoni develops hepatic fibrosis. HLA studies in Egypt and a candidate gene search in a Sudanese population indicate that the host's genetics contribute to disease susceptibility. In an Egyptian community, 32.7% of individuals 11 years and older had significant fibrosis by WHO ultrasound criteria. Linkage to 10 candidate genes was tested using 89 affected sibling pairs from 40 pedigrees in this community. The candidates included genes that initiate fibrosis, participate in collagen synthesis, or control collagen degradation. Two to four single-nucleotide polymorphisms (SNPs) were genotyped per locus, and 188 individuals were genotyped at 48 markers. Model-free modified Haseman-Elston analysis identified linkage to a SNP in the interferon gamma receptor locus (P=0.000001). There was also weak evidence for linkage to the interleukin 13-4 region and tissue growth factor beta 1. 相似文献
8.
A Matter 《Journal of immunological methods》1976,12(3-4):289-301
Culture conditions have been established for optimal generation of cytotoxic T lymphocytes (CTL) in one-way mixed lymphocyte cultures (MLC). The responder cell concentration was found to be most critical. In general the more active the proliferation was, the lower was the optimum for CTL generation. Optimal proliferation was usually found to occur at lower cell concentrations than optimal CTL generation. Above the optimal CTL generation proliferation also decreased, most likely due to overcrowding. These observations were made on both unpurified and nylon wool-passaged spleen cells, though the latter generally produced higher levels of cytotoxic activity per equal number of harvested cells. Cells prestimulated for 2 or 4 days in the absence or presence of antigen (M-locus differences) were unable to mount an effective response when restimulated with another antigen presenting an H-2 difference. This hyporesponsiveness was not due to the exhaustion of the culture medium or the presence of dead cells (since these were removed before restimulation). A high degree of hyporesponsiveness was also induced in the absence of antigen during prestimulation which rendered antigenic competition highly unlikely. Overcrowding could be excluded since the observed inhibition could not be diluted out by lowering the responder cell concentrations. A carry-over of CTL destroying newly added antigen (Fitch et al., 1975) could not account for our observations since in the system utilized (M-locus stimulation) there was no generation of CTL (Festerstein, 1973; R?llinghoff et al., 1975). The development of suppressor cells would seem the most likley explanation of the data. 相似文献
9.
D Geleick H Müller A Matter J Torhorst U Regenass 《Cancer Genetics and Cytogenetics》1990,46(2):217-229
Chromosome counts were performed on 1,100 cells from 17 malignant breast carcinomas and on 168 cells of four normal tissue samples after amethopterin treatment and G-banding. Karyotypes were established from 216 cells of 11 tumor-derived cultures and from 47 cells of four nonmalignant tissue-derived cultures. Karyotypes of cells from nonmalignant samples showed a normal diploid chromosomal constitution with no consistent loss or gain of a specific chromosome. Structural chromosomal abnormalities were not observed. Tumor-derived cultures could be distinguished from normal cultures on the basis of a significantly increased incidence of numerical changes and structural chromosomal aberrations. In nine of 11 tumor-derived cultures, numerically normal cells were shown to be pseudodiploid, with frequencies ranging to 43% (mean, 13.2%) of the diploid cells. In agreement with previous reports, cytogenetic analyses showed predominantly diploid cells. Clonal numerical changes of chromosomes 17, 18, 20, and 21 could be detected in three tumor samples. Clonal structural abnormalities could be observed in two of 11 analyzed tumours. A t(6;12)(p21;p13) and an enlarged chromosome 7 (7q+) were found in a patient with invasive ductal carcinoma. An inversion of chromosome 7 [inv(7)(q11.2q32)] was observed in one case, also diagnosed as invasive ductal carcinoma. The significance of these findings in relation to clinical data is discussed. 相似文献
10.
The impact of patient delay and physician delay on the outcome of laparoscopic cholecystectomy for acute cholecystitis 总被引:6,自引:0,他引:6
Eldar S Eitan A Bickel A Sabo E Cohen A Abrahamson J Matter I 《American journal of surgery》1999,178(4):303-307
BACKGROUND: Laparoscopic cholecystectomy is now used in the management of acute cholecystitis. Under these circumstances unfavorable conditions may result in conversion and complications. Information about these conditions may help in planning the laparoscopic approach or in proceeding directly to open cholecystectomy. This study was initiated to evaluate perioperative factors associated with conversion and complications of laparoscopic cholecystectomy in acute cholecystitis. Special attention was paid to the duration of complaints until surgery, to the delay on the part of the patient, and to the delay on the part of the physician. METHODS: Between January 1994 and December 1997, we attempted to perform laparoscopic cholecystectomy on 348 patients with acute cholecystitis. All perioperative data were collected on standardized forms. RESULTS: There were 182 cases (52%) of acute uncomplicated cholecystitis, 90 (26%) of gangrenous cholecystitis, 33 of hydrops (9.5%), and 43 of empyema of the gallbladder (12.5%). Seventy six patients (22%) needed conversion to open cholecystectomy and complications occurred in 57 cases. Advanced cholecystitis was associated with significant patient delay (P = 0.01), and it had a significantly higher conversion rate (39%) compared with early cholecystitis (14.5%); (P <0.00001). Conversion rates were also associated with male gender (P = 0.0017), a history of biliary disease (P = 0.0085), and a patient delay of >48 hours (P = 0.028). The total and infectious complication rates were associated with an age older than 60 years (P = 0.023 and 0.007, respectively) and male gender (P = 0.026 and 0.014, respectively). CONCLUSIONS: In acute cholecystitis, patient delay is associated with a high conversion rate. Early timing of laparoscopic cholecystectomy tends to reduce the conversion rate, as well as the total and the infectious complication rates. Male gender, a history of biliary disease, and advanced cholecystitis are associated with conversion. Male and older patients are associated with a high total and infectious complication rates. 相似文献