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A convenient approach to the new 2-aminobenzophenone analogue 4 is reported. Condensation reactions of 4 with ortho esters or amide acetals, respectively, followed by intramolecular cyclisations were found to provide smooth access to (4-pyridazinyl)-substituted quinolines 10, 13a,b , and the quinazoline derivative 15 .  相似文献   
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Systemic angioendotheliomatosis is a very rare malignant disease characterized by intravascular neoplastic proliferation of reticuloendothelial cells. According to the clinical features three different types of prognostic value can be distinguished: Exclusive skin involvement; Progressive skin lesions disseminating to internal organs; Aggressive and lethal type affecting primarily internal organs. Until now about 60 cases of systemic angioendotheliomatosis have been reported in the literature. Here we describe the first well-documented case with almost isolated lung involvement. The presentation of morphologic and clinical signs and differential-diagnostic considerations are followed by a critical review of the literature.  相似文献   
4.
Budd–Chiari syndrome (BCS) is characterized by obstruction of the hepatic venous outflow tract. Therapeutic options for BCS are limited. We report a case of a 21-year-old woman with protein S and C deficiency with gross ascites. Treatment with transjugular intrahepatic portosystemic shunt (TIPS) was attempted, which revealed occluded hepatic veins, so transcaval TIPS was performed. No serious procedure-related complication occurred. After successful shunt creation, the patient's symptoms subsided and she was discharged and followed up for 6 months.  相似文献   
5.
Live and boiled cells of 16 strains of Aeromonas caviae, isolated from patients with diarrhea, agglutinated with Shigella boydii 5 antiserum in a slide test. Further studies with seven selected strains showed agglutination with boiled cells in a tube test. Lipopolysaccharide antigen extracted from one of these strains cross-reacted with S. boydii 5 in enzyme-linked immunosorbent assay and immunoblot studies. Either all or the majority of the seven strains possessed properties deemed to be diarrheagenic.  相似文献   
6.
Zusammenfassung Auf den Organismus einwirkende Stressoren, die einen gewissen Schwellenwert überschritten haben, bewirken deutliche StoffwechselverÄnderungen; diese Tatsache ist seit langem experimentell bewiesen.Wir konnten zeigen, da\ diese VerÄnderungen bei Einfach- und Mehrfachstre\ verschieden sind und da\ die StoffwechselverÄnderungen bei wiederholter Belastung offensichtlich Habituationsbzw. AdaptationsvorgÄngen unterworfen sind. Derartige stre\induzierte Stoffwechselmechanismen laufen aber für die einzelnen Blutfette und die Glukose unterschiedlich ab, was durch die verschiedenen Funktionen der einzelnen Parameter in Belastungssituationen erklÄrbar ist. Die Analyse dieser VerÄnderungen ist für die PrÄvention von stre\induzierten Stoffwechelentgleisungen von gro\er Bedeutung.Mit finanzieller Unterstützung des österreichischen Fonds zur Förderung der wissenschaftlichen Forschung  相似文献   
7.
Plasmid profiles and antimicrobial susceptibility patterns of 343 strains of Shigella dysenteriae type 1, obtained from 18 different geographical locations, were analyzed. Three plasmids, with molecular sizes of 140, 6, and 2 megadaltons (MDa), were present in 94, 98, and 96%, respectively, of the 343 strains isolated during either epidemic or nonepidemic periods from 1965 to 1987. In addition to these plasmids, 83% of the strains harbored a 4-MDa plasmid and 25% harbored a 20-MDa plasmid. Various plasmid profiles were observed in which the 140-, 6-, and 2-MDa plasmids occurred commonly, irrespective of the place of isolation and drug resistance pattern of the strains. Certain profiles showed significant association with drug resistance patterns. These findings suggest that three plasmids, of molecular sizes 140, 6, and 2 MDa, are unique to S. dysenteriae type 1 strains and may indicate the global spread of a pathogenic bacterial clone. Additionally, these core plasmids, plus plasmids of various other sizes, could be used to identify emerging subclones which are causing both epidemic and sporadic disease. Thus, plasmid profiles of S. dysenteriae type 1 strains can be used to monitor possible pandemic strains as well as individual epidemic strains.  相似文献   
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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   
10.
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   
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