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21.
Jan Frisell Gunnar Eklund Lars Hellström Ulla Glas Anders Somell 《Breast cancer research and treatment》1989,13(1):79-87
In screening programmes it is important to assess a preliminary effectiveness of the screening method as soon as possible in order to forecast survival figures. In March 1981 a controlled single-view mammographic screening trial for breast cancer was started in the south of Stockholm. The population invited for screening mammography consisted of 40,000 women aged 40–64 years, and 20,000 women served as a well-defined control group. The main aim of the trial was to determine whether repeated mammographic screening could reduce the mortality in the study population (SP) compared to the control population (CP).The cumulative number of advanced mammary carcinomas in the screening and the control populations from the first five years of screening have shown a tendency towards more favourable stages in the screened population aged 40–64 years. A breakdown by age suggests an effect in age group 50–59 years, but not yet in age groups 40–49 and 60–64 years.When comparing the rates of stage II+ cancer, an increased number is found in the study group. As the total rate of breast cancer is higher in SP than in CP, there ought to be a concealed group of stage II+ cancers in the CP which makes the comparison biased. A new approach has been designed, where an estimation of the hidden number of stage II+ cancers in CP is added to the clinically detected cases, and in this respect a comparison has shown a decrease in the cumulative number of advanced cancers in the SP in relation to the CP (p<0.05). According to this it could be important to add the estimated number of undetected, hidden cases in the control group in order to utilize the difference in detection rate in the screening- and control group respectively. 相似文献
22.
Intranasal immunization of mice with group B streptococcal protein rib and cholera toxin B subunit confers protection against lethal infection 总被引:3,自引:0,他引:3
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Intranasal immunization of mice with Rib, a cell surface protein of group B streptococcus (GBS), conjugated to or simply coadministered with the recombinant cholera toxin B subunit, induces systemic immunoglobulin G (IgG) and local IgA antibody responses and confers protection against lethal GBS infection. These findings have implications for the development of a human GBS vaccine. 相似文献
23.
Thierbach R Schulz TJ Isken F Voigt A Mietzner B Drewes G von Kleist-Retzow JC Wiesner RJ Magnuson MA Puccio H Pfeiffer AF Steinberg P Ristow M 《Human molecular genetics》2005,14(24):3857-3864
We have disrupted expression of the mitochondrial Friedreich ataxia protein frataxin specifically in murine hepatocytes to generate mice with impaired mitochondrial function and decreased oxidative phosphorylation. These animals have a reduced life span and develop multiple hepatic tumors. Livers also show increased oxidative stress, impaired respiration and reduced ATP levels paralleled by reduced activity of iron-sulfur cluster (Fe/S) containing proteins (ISP), which all leads to increased hepatocyte turnover by promoting both apoptosis and proliferation. Accordingly, phosphorylation of the stress-inducible p38 MAP kinase was found to be specifically impaired following disruption of frataxin. Taken together, these findings indicate that frataxin may act as a mitochondrial tumor suppressor protein in mammals. 相似文献
24.
Genome profiles of bilateral dysgerminomas, a unilateral gonadoblastoma, and a metastasis from a 46, XY phenotypic female 总被引:3,自引:0,他引:3
Kildal W Kraggerud SM Abeler VM Heim S Tropé CG Kristensen GB Risberg B Lothe RA Danielsen HE 《Human pathology》2003,34(9):946-949
We present a case report of a 16-year-old, phenotypic female with bilateral dysgerminomas, a unilateral gonadoblastoma, and a peritoneal metastasis. The patient's constitutional karyotype was 46,XY. The chromosomal copy number, examined by the comparative genomic hybridization technique, showed 3 gains in the dysgerminoma of the right ovary, 6 gains in the dysgerminoma of the left ovary, and 2 gains and 1 loss in the gonadoblastoma of the left ovary. The metastasis showed 5 gains of which 4 were also observed in the dysgerminoma of the left ovary. The DNA ploidy classifications of the gonadoblastoma and the dysgerminoma in the right ovary were tetraploid, whereas the dysgerminoma in the left ovary and the metastasis were aneuploid. We therefore propose that the metastasis most probably developed from the dysgerminoma of the left ovary. 相似文献
25.
Comparison of serum hepatitis C virus RNA and core antigen concentrations and determination of whether levels are associated with liver histology or affected by specimen storage time
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Lagging LM Garcia CE Westin J Wejstål R Norkrans G Dhillon AP Lindh M 《Journal of clinical microbiology》2002,40(11):4224-4229
An enzyme immunoassay has recently been developed for the hepatitis C virus (HCV) core antigen. To evaluate the possible association between core antigen and HCV RNA levels with regards to the change in liver histology over time as well as study the effect of duration of storage on viral load results, sequential sera were analyzed from 45 patients with chronic HCV infection who had undergone two or more liver biopsies. A relatively strong association was found between the core antigen and HCV RNA concentrations (r(s) = 0.8), with a core antigen level of 1 pg/ml corresponding to approximately 1,000 IU/ml. All 42 sera with detectable HCV RNA at the time of the second biopsy had core antigen concentrations above 1 pg/ml, and the three sera without detectable HCV RNA had concentrations below 1 pg/ml. No association was found between HCV RNA or core antigen levels and the stage of fibrosis in biopsy samples, progression of fibrosis, necro-inflammatory grade, steatosis, genotype, alanine aminotransferase level, or alcohol consumption. A significant association was demonstrated between the storage time of the samples and both the HCV RNA and core antigen concentrations. The median log HCV RNA concentrations (international units/milliliter) were 3.92 for the sera obtained at the time of the first biopsy (median storage time, 13.0 years) and 4.41 for the sera obtained at the time of the second biopsy (median storage time, 6.6 years) compared to 5.96, the median for 102 different routine clinical patient samples. 相似文献
26.
Micci F Walter CU Teixeira MR Panagopoulos I Bjerkehagen B Saeter G Heim S 《Cancer Genetics and Cytogenetics》2003,144(2):119-124
Endometrial stromal sarcomas (ESS) are rare neoplasms with the capacity both to invade the myometrium locally and to give rise to extrauterine metastases. Cytogenetic abnormalities have been reported in 22 cases of ESS, mostly involving rearrangements of chromosomes 6, 7, and 17. The most characteristic translocation of this tumor type, t(7;17)(p15 approximately p21;q12 approximately q21), was recently shown to generate a JAZF1/JJAZ1 fusion gene. We report three additional cases of ESS with abnormal karyotypes, whose interpretation was based on the combined analysis by conventional cytogenetics and cross-species color banding FISH (RxFISH). The combination of G-banding and RxFISH in every case gave additional information beyond that obtained by either technique alone, determining the identity of even complex inter- as well as intrachromosomal rearrangements. In one of the three tumors, a t(7;17) was seen; molecular genetic studies identified the JAZF1/JJAZ1 fusion gene in this case. Two tumors had aberrations that included structural changes of chromosome arms 6p and 7p. Evidently, karyotypic, and hence pathogenetic, heterogeneity exists for tumors classified as endometrial stromal sarcomas based on their phenotypic features. 相似文献
27.
Usefulness of high-resolution comparative genomic hybridization (CGH) for detecting and characterizing constitutional chromosome abnormalities 总被引:6,自引:0,他引:6
Comparative genomic hybridization (CGH) is a technique for detection of chromosomal imbalances in a genomic DNA sample. We here report the application of the recently developed method of high-resolution CGH on DNA samples from 66 children having various degrees of delayed psychomotor development with or without clear dysmorphic features and congenital malformations. In 5 of 50 patients with apparently normal karyotypes, a deletion or duplication was revealed by CGH. Only one of these cases had a subtelomeric rearrangement. In one of seven cases with a de novo apparently balanced translocation, deletions were found. In all nine cases where the origin of a marker chromosome or additional chromosomal material was difficult to determine, CGH gave a precise identification. The following findings were from cases having a deletion or duplication as the sole chromosomal imbalance; dup(2)(p16p21), del(4)(q21q21), del(6)(q14q15), del(6)(p12p12), dup(6)(q24qter), and dup(15)(q11q13). One case had dup(9)(p11pter) combined with a very small subtelomeric deletion on 6q. In our hands, CGH is highly useful not only for identifying known chromosomal imbalances, but also for finding elusive deletions or duplications in the large group of children with developmental delay with or without congenital abnormalities. In such cases, the diagnostic yield of CGH appears to be higher than what has been reported from subtelomeric FISH screening. 相似文献
28.
Expression of CD44 in effusions of patients diagnosed with serous ovarian carcinoma – diagnostic and prognostic implications 总被引:2,自引:0,他引:2
Berner HS Davidson B Berner A Risberg B Kristensen GB Trope CG Van de Putte G Nesland JM 《Clinical & experimental metastasis》2000,18(2):197-202
CD44 is a family of cell adhesion molecules involved in a variety of cellular functions. The present study analysed the expression
of two CD44 isoforms in serous effusions of patients diagnosed with ovarian carcinoma and corresponding primary and metastatic
lesions. Fifty-eight effusions, 23 primary ovarian tumours, and 44 metastatic lesions were studied for protein expression
of CD44s and v3-10 using immunohistochemistry. Results were correlated with clinical parameters. CD44v3-10 was seen in carcinoma
cells in the majority of cases at all sites. Malignant effusions showed an up-regulation of CD44s compared to both primary
tumours and metastatic solid lesions. Mesothelial cells frequently expressed CD44s, but were rarely immunoreactive for v3-10.
CD44s immunoreactivity in cancer cells in effusions was significantly more often observed in patients with FIGO stage 3 than
in stage 4 patients (P = 0.045). Staining results did not correlate with age, effusion site, metastatic site, tumour grade or residual tumour mass
after initial surgery. Likewise, comparison of overall and disease-free survival with expression of the CD44 isoforms studied
did not reveal any statistically significant associations. The up-regulation in CD44 levels in effusions, primarily in stage
3 disease, suggests that adhesion of ovarian carcinoma cells to mesothelium may be regulated at the level of CD44s expression,
and provides further evidence of phenotypic alteration in the transition from primary tumour cell clones to effusions. The
similar expression profile of CD44 in carcinoma cells in peritoneal and pleural effusions supports our previous observations
and the hypothesis that carcinoma cells in peritoneal effusions are truly metastatic.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
29.
John M. Opitz Gunnar B. Stickler James F. Reynolds 《American journal of medical genetics. Part A》1987,27(4):971-975
We report on a consanguineous Brazilian couple whose 2 children had tibial aplasia-ectrodactyly. Femoral bifurcation was present in one of the affected children. The relationship of tibial aplasia-ectrodactyly to the Gollop-Wolfgang complex is discussed. Clinical and genetic aspects of the conditions involving tibial aplasia and femoral bifurcation are discussed. 相似文献
30.
Gunnar Rockborn 《Archives of virology》1958,8(4):493-499
Summary Studies on serological distemper immunity in an urban dog population are reported. Presumably maternal antibodies were demonstrable in the youngest age groups with successive decrease in rate of immunity as well as in antibody titers with age, insignificant levels being reached at 5 to 6 months after birth. Antibodies in high titers indicating subclinical infections began to appear in year-old animals, and dogs above the age of 2 years showed immunity in 91% of the cases. A study of the age distribution of immunity and reported incidence of clinical disease indicated that distemper infection, frequent in the years preceding 1953, had been relatively rare in the period 1953 to 1955.This work was supported by grants from the Research Fund of the Royal Veterinary College. 相似文献