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101.
102.
A simultaneous analysis of aspirin and nonaspirin salicylates in solid pharmaceutical dosage forms is described. Two separate extraction procedures are employed, one for plain aspirin tablets and one for tablets containing aspirin plus buffers or antacids. The analyses of the extracted samples are accomplished by a stabilized normal-phase high-performance liquid chromatographic (HPLC) procedure. Prepared samples and standards are stable for up to 24 h, and the methodology is suitable for an automated HPLC system.  相似文献   
103.
A nonsolvolytic (solid-state) acetylation of codeine phosphate in the presence of aspirin to yield acetylcodeine phosphate is reported. GLC assays for the simultaneous determination of aspirin and salicylic acid and codeine and acetylcodeine are described. The apparent heat of activation for codeine phosphate is estimated, and the possible reaction mechanisms are discussed.  相似文献   
104.
The Herpesviridae contain a group of highly conserved proteins designated the Herpes UL33 Superfamily (pfam03581). The Varicella-zoster virus (VZV) homolog, encoded by the ORF25 gene, was used to generate a GST-ORF25 fusion protein. Purified GST-ORF25 was used to generate a polyclonal rabbit antiserum that detected the 17.5 kDa ORF25 protein (pORF25) in VZV infected cells. In pull-down assays, GST-ORF25 interacted with a number of encapsidation proteins including ORF30, ORF42 (the second exon of ORF45/42) and itself. The self-interaction was confirmed via a yeast two-hybrid assay. Additionally, pORF25 and pORF30 were shown to co-immunoprecipitate from VZV infected cells. Our results suggest that pORF25 is part of the trimeric terminase complex for VZV. However, combined with data from previous studies on HSV-1 and Kaposi's sarcoma associated herpesvirus (KSVH), we hypothesize that VZV pORF25 and the Herpes UL33 Superfamily homologs are not encapsidation proteins per se but instead work to bring viral proteins together to form functional complexes.  相似文献   
105.
106.
Splenic infarction has been associated with haematologic and tromboembolic disorders and, more rarely, with infectious diseases. A case of splenic infartion during an attack of brucellosis is reported. Symptoms included persistent left upper quadrant pain and fever. An abdomen scan confirmed the presence of a triangular area of hypodensity in the spleen. Serum and culture exams confirmed the diagnosis of brucellosis. The patient recovered once a course of antibiotic therapy was completed, after 2 and half months.  相似文献   
107.
In order to improve the knowledge of host/pathogenic agent interaction and to obtain a more careful estimation of risk related to ingestion of food contaminated by Vibrio spp., the effects of bile extracts have been studied. The growth of one V. fluvialis, two V. alginolyticus, and three V. parahaemolyticus strains, isolated from mollusks and crustaceans, has been determined to evaluate their adaptability to intestinal environment. Moreover, the expression of virulence factors responsible for the colonization, as bacterial "swarming mobility", biofilm production, adherence on epithelial cells and hydrophobicity, has been evaluated. Using a bile concentration of 1.5%, all examined strains showed a constant inhibitory effect, quite moderate in the first growth phases. Bile increased the "swarming mobility" and biofilm production; also the adherence was favored, but only after adaptation and during the early logarithmic phase. The decreased hydrophobicity could explain the reduction of adherence during the stationary phase. Studying the phenotypic expression of virulence factors in "minor vibrios" in the presence of bile, it was possible to extend the knowledge about their pathogenetic mechanisms owing to the ingestion of contaminated food. That permits a more careful estimation of risk related to the contamination, considering the high frequency of isolation of these species in some seafood.  相似文献   
108.
The PEARLS study prospectively monitored selected nosocomial pathogens from 38 centres in 13 European, three Middle Eastern countries and South Africa during 2001-2002. Extended spectrum beta-lactamase (ESBL) production rates among Escherichia coli, Klebsiella pneumoniae, and Enterobacter spp. were 5.4% (142/2609), 18.2% (401/2,206) and 8.8% (204/2,328), respectively, for all study sites. The overall ESBL production rate for the combined Enterobacteriaceae was 10.5% (747/7,143), highest in Egypt, 38.5%, and Greece, 27.4%, and lowest in The Netherlands, 2.0%, and Germany, 2.6%. IEF, PCR and DNA sequencing determined 10.7% false positives among Enterobacter spp. when using NCCLS guidelines to screen for ESBL production. The prevalence of nosocomial methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium was 32.4% (294/908) and 8.7% (83/949), respectively. PEARLS provides baseline data against which prospective changes in resistant determinants and outcomes can be measured in this ongoing study.  相似文献   
109.
Murine cytomegalovirus (MCMV) m137 null mutants, Deltam137A and Deltam137B, were generated by inserting a gpt cassette into a deleted region of the open reading frame. A polyclonal antiserum produced to an Escherichia coli expressed gst-m137 fusion protein was used to show that a 38 kDa polypeptide corresponding to the predicted m137 gene product was present in NIH 3T3 fibroblasts infected with wild-type MCMV but was not detected in Deltam137 infected cells. The protein did not fractionate with infected cell membranes and was not detectable in purified wild-type virions. Plaque size, plaque morphology, and viral yield did not differ significantly between Deltam137 and wild-type MCMV infected 3T3 fibroblasts. The results showed that deletion of the 38 kDa protein did not negatively effect viral growth in 3T3 fibroblasts indicating that the m137 gene product is not essential for replication in these cells. In vivo analysis revealed that two independently isolated m137 mutants showed a significant delay in time until death but ultimately killed 100% of the mice in a SCID mouse model of virulence.  相似文献   
110.
Summary.  The herpes simplex virus type 1 (HSV-1) UL45 gene encodes an 18 kDa virion envelope protein whose function remains unknown. Previous studies using a UL45 null mutant, UL45Δ, demonstrated that deletion of the UL45 gene altered plaque size in Vero and HeLa cells, but was not essential for replication in these cell types. The goal of this study was to determine if mutation of the UL45 gene influenced virus growth in the CNS. Two UL45 mutants, as well as a repaired revertant virus, were constructed and tested for their ability to cause encephalitis and replicate in the CNS. The UL45 mutants were not lethal when 1 × 103 pfu were injected intracerebrally into Balb/c mice. In contrast, at inocula greater than 1 × 103, the UL45 mutants were lethal. In vivo growth curves derived from mice inoculated intracerebrally with 1 × 103 pfu of virus revealed that the mutants grew poorly compared to wild type or revertant viruses. These results suggest that the 18 kDa UL45 gene product is required for efficient growth in the central nervous system at low doses. We propose that the UL45 gene may play an important role under the conditions of a naturally acquired infection. Received June 23, 2001 Accepted November 1, 2001  相似文献   
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