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1.
2.
Fifty couples and their children with Down syndrome (D.S.) were typed for HLA-A and HLA-B antigens and compared to 50 control families and 464 blood donors. The parental origin of the extra chromosome 21 was determined by cytogenetic methods. All individuals were caucasians and there was no history of consanguinity. No excessive HLA sharing was present in D.S. parents. The mothers of D.S. shared no more HLA antigens with their D.S. children than the control mothers with their normal children (14% vs. 18%). Thirteen of the fifty pairs (26%) (parent in whom the nondisjunction occurred and D.S. child) shared three HLA antigens at the A and/or B locus. This was not significantly higher than the proportion in the control group (12/50 or 24%). These data suggest that it is not the sharing of HLA-A and HLA-B antigens between the parents or between the parent who was the origin of the nondisjunction and the D.S. child that is related either to the occurrence of trisomy 21 zygotes or to prenatal survival of affected embryos and fetuses. 相似文献
3.
Zusammenfassung
Grundlagen: Seit Einführung der laparoskopischen Cholezystektomie wird diskutiert, ob bei diesem Eingriff Einmal- oder wiederverwendbare
Instrumente eingesetzt werden sollten. Argumenten der Wirtschaftlichkeit wurden Aspekte der Sicherheit und Hygiene entgegengestzt.
Eine Beurteilung des Ger?teeinsatzes unter Berücksichtigung der Kosten als auch des Nutzwertes der Instrumente ist bis heute
nicht erfolgt.
Methodik: Es wurde ein Kostenvergleich von 3 Varianten des Instrumenteneinsatzes durchgeführt (1. wiederverwendbare Instrumente, 2.
Einmalger?te, 3. kombinierte Anwendung). Der Wirtschaftlichkeitsrechnung wurde eine Nutzwertbestimmung der einzelnen Instrumente
durch die Operateure entgegengestellt.
Ergebnisse: Durch den Einsatz von wiederverwendbaren Instrumenten ist eine betr?chtlichen Kostenreduktion (5888 ATS bei ausschlie?licher
Anwendung von wiederverwendbaren Ger?ten. 3945 ATS bei kombiniertem Einsatz) zu erreichen. Der Nutzenvergleich zeigte beim
Clipsetzer und dem Port für die erste Insertion Vorteile für die Einmalinstrumente.
Schlu?folgerungen: Aufgrund der Ergebnisse von Kostenkalkulation und Nutzwertbestimmung stellt der kombinierte Einsatz von wiederverwendbaren
und Einmalinstrumenten derzeit die beste Alternative dar.
相似文献
4.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
5.
Summary A neurological complication occurs in 40–60% of HIV infected patients during the course of the disease. In 10–20% the neurological complication is the first manifestation of the HIV infection. A reliable neuropathological diagnosis is a prerequisite for a specifically selected treatment. While modern computer-assisted imaging techniques, such as computed tomography or magnetic resonance imaging, do possess a high sensitivity, they do not as a rule permit an unambiguous diagnosis.Between October 1989 and July 1994 we biopsied 38 HIV infected patients stereotactically. The indication for the biopsy was determined by having radiologically detectable lesions with no regression tendency in patients under antitoxoplasmosis therapy. In 89% an unambiguous diagnosis wa made based on the biopsy; 11 % of the biopsies were not diagnostic. For the most part, toxoplasmosis (31%) and progressive multifocal leucoencephalopathy (29%) were involved. 18% of the patients suffered from a non-Hodgkin lymphoma. The foci were primarily frontal (47%), parietal (21%) or localised in the basal ganglia area (11%). The result of the biopsy led to a change in treatment for 52% of the patients. Morbidity and mortality of the operation were 0%.The results or our research series are similar to other groups. It was shown that stereotactic brain biopsy is a safe and effective method for establishing a sound basis for treating the frequently life-threatening cerebral complications of AIDS. 相似文献
6.
Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP) 总被引:2,自引:2,他引:2
Roepman R; Bauer D; Rosenberg T; van Duijnhoven G; van de Vosse E; Platzer M; Rosenthal A; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(6):827-833
The gene for the most frequent from of X-linked retinitis pigmentosa
(XLRP), RP3, has been assigned by genetic and physical mapping to a segment
of less than 1000 kbp, which is flanked by the marker DXS1110 and the
ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have
screened the DNA of 30 unrelated patients with XLRP by employing a
representative set of YAC-derived DNA fragments that were generated by
restriction enzyme digestion and PCR amplification. In one of these
patients, a 6.4 kbp microdeletion was detected which was not present in the
DNA of 444 male controls. A cosmid contig spanning the deletion was
constructed and used to isolate cDNAs from retina-specific libraries. Exons
corresponding to these expressed sequences as well as other putative exons
were identified by sequencing more than 30 kbp of the critical region. So
far, no point mutations in these putative exon sequences have been
identified.
相似文献
7.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
8.
Gliwitzky B. Conrad D. Thierbach A. Kumpch M. Schwietring J. Ruppert M. Armbruster W. 《Notfall & Rettungsmedizin》2021,24(8):1107-1113
Notfall + Rettungsmedizin - Anfang September 2019 wurde ein neuer Dual-use-RTH/ITH-Standort in der Westpfalz etabliert. Während der Einarbeitung der medizinischen Crew entstand bei den Autoren... 相似文献
9.
Comprehensive mutational scanning of the p53 coding region by two- dimensional gene scanning 总被引:2,自引:0,他引:2
A comprehensive mutational scanning test for the p53 coding region based on
multiplex PCR and two-dimensional DNA electrophoresis was designed and
evaluated. In a 2-step multiplex PCR, the p53 coding region (exons 2-11)
was amplified as a single 8646-bp fragment by long- distance PCR in step
one. This fragment served as a template for the subsequent co-amplification
of the individual exons in two multiplex groups in step two. The multiplex
products were then separated, first on the basis of size in non-denaturant
polyacrylamide gels and then on the basis of sequence by denaturing
gradient gel electrophoresis (DGGE). Primers for optimal PCR, melting
behavior and 2-D gel distribution were designed using a recently developed
computer program. The resulting two-dimensional gene scanning (TDGS) test
was evaluated by screening, in a blinded fashion, 29 coded DNA samples from
Li- Fraumeni syndrome patients with previously identified germline
mutations. All mutations were correctly detected. This assay provides an
accurate, cost-effective and non-radioactive method for simultaneous
mutational scanning of all p53 coding exons.
相似文献
10.
Associations between both genetic and environmental biomarkers and lung cancer: evidence of a greater risk of lung cancer in women smokers 总被引:3,自引:4,他引:3
Tang DL; Rundle A; Warburton D; Santella RM; Tsai WY; Chiamprasert S; Hsu YZ; Perera FP 《Carcinogenesis》1998,19(11):1949-1953
This molecular epidemiologic case-control study of lung cancer incorporated
three complementary biomarkers: the glutathione S- transferase M1 (GSTM1)
null genotype, a potential marker of susceptibility, and polycyclic
aromatic hydrocarbon-DNA adducts (PAH- DNA) and sister chromatid exchanges
(SCE), both indicators of environmentally induced genetic damage.
Associations between biomarkers and lung cancer were investigated, as were
possible gene-environment interactions between the GSTM1 null genotype and
tobacco smoke exposure. Subjects included 136 primary non-small cell lung
cancer surgical patients and 115 controls at the Columbia Presbyterian
Medical Center. Questionnaire and Tumor Registry data, pre-treatment blood
samples and biomarker measurements on blood were obtained. Overall, GSTM1
null genotype was significantly associated with lung cancer [odds ratio
(OR) = 2.04, 95% confidence interval (CI) = 1.13-3.68]. ORs for GSTM1 and
lung cancer were significant in females (2.50, 1.09-5.72) and smokers
(2.25, 1.11-4.54) and not significant in males (1.4, 0.58-3.38) and
non-smokers (0.88, 0.18-4.33). However, ORs for males versus females and
smokers versus non-smokers did not differ significantly. The OR for GSTM1
and lung cancer in female smokers was 3.03 (1.09- 8.40), compared with 1.42
(0.53-4.06) in male smokers. In contrast to PAH-DNA adducts in leukocytes,
SCE did not differ between cases and controls. Neither biomarker differed
significantly between the two GSTM1 genotypes. The combined effect of
elevated PAH-DNA adducts and GSTM1 genotype on case-control status (16.19,
1.2-115) appeared multiplicative. Results suggest that the effect of the
GSTM1 null genotype is greatest in female smokers, which is consistent with
other evidence that indicates that women are at higher risk of lung cancer
than males, given equal smoking. Persons with both the GSTM1 deletion and
elevated PAH-DNA adducts may represent a sensitive subpopulation with
respect to carcinogens in tobacco smoke and other environmental media.
相似文献