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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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The pharmacotherapy of schizophrenia remains an ongoing challenge for researchers and clinicians alike. Current medications remain suboptimal to effectively treat this illness despite the recent surge of what are considered to be better antipsychotics: the atypicals. The atypicals cause fewer extrapyramidal symptoms and tardive dyskinesia, but there is growing concern regarding the significant long-term metabolic and cardiac adverse effects of these novel antipsychotics. There are differences among the atypicals in their propensity to produce these adverse effects, and clinicians should weigh the risk-benefit ratio for each drug with each individual patient. Diabetes, heart disease, obesity, and unhealthy lifestyle choices are on the rise in the general population, and individuals with chronic schizophrenia are even more at risk. The dilemma clinicians face in trying to avoid the neurological morbidity of the typicals (extrapyramidal side effects and tardive dyskinesia) is the risk of consequently exposing patients to both the morbidity and potential mortality of the atypicals (cardiovascular, endocrine, and metabolic adverse effects). The importance of baseline investigations and monitoring at regular intervals as well as identification of patients at risk for obesity, diabetes, and cardiovascular morbidity has become crucial. Informed decision making is essential for successful antipsychotic pharmacotherapy. For a condition, which often necessitates long-term pharmacotherapy, the importance of prevention and (or) minimization of morbidity and mortality related to adverse effects of such pharmacotherapy cannot be understated.  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   
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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   
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Localized, diffuse, and aggregative adherence patterns of Escherichia coli identified with specific DNA probes were compared in cell culture adherence assays by using the Center for Vaccine Development, Baltimore, method, the University of Texas Medical School, Houston (UTH), method, and a modified UTH method. Increasing postwash incubation time from 2 to 4 h in the modified UTH method allowed identification of enteroaggregative E. coli, which was otherwise not identified by the original UTH method.  相似文献   
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The slow acquisition of protection against Plasmodium falciparum malaria probably reflects the extensive diversity of important antigens. The variant surface antigens (VSA) that mediate parasite adhesion to a range of host molecules are regarded as important targets of acquired protective immunity, but their diversity makes them questionable vaccine candidates. We determined levels of VSA-specific immunoglobulin G (IgG) in human plasma collected at four geographically distant and epidemiologically distinct localities with specificity for VSA expressed by P. falciparum isolates from three African countries. Plasma levels of VSA-specific IgG recognizing individual parasite isolates depended on the transmission intensity at the site of plasma collection but were largely independent of the geographical origin of the parasites. The total repertoire of immunologically distinct VSA thus appears to be finite and geographically conserved, most likely due to functional constraints. Furthermore, plasma samples frequently had high IgG reactivity to VSA expressed by parasites isolated more than 10 years later, showing that the repertoire is also temporally stable. Parasites from patients with severe malaria expressed VSA (VSASM) that were better recognized by plasma IgG than VSA expressed by other parasites, but importantly, VSASM-type antigens also appeared to show substantial antigenic homogeneity. Our finding that the repertoire of immunologically distinct VSA in general, and in particular that of VSASM, is geographically and temporally conserved raises hopes for the feasibility of developing VSA-based vaccines specifically designed to accelerate naturally acquired immunity, thereby enhancing protection against severe and life-threatening P. falciparum malaria.  相似文献   
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Traditional enteropathogenic Escherichia coli serotypes demonstrate a plasmid-mediated localized adherence in cultured HeLa or HEp-2 cells and induce an attaching-effacing intestinal lesion, both of which are considered pathognomonic and causes of diarrhea. This study describes three E. coli strains from infantile diarrhea which share these properties but belong to serotypes (O2:H2, O2:H25 and O15:H2) not considered enteropathogenic.  相似文献   
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