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81.
SL Anliker MS McClure TC Britton EA Stephan SR Maple GG Cooke 《Canadian Metallurgical Quarterly》1994,83(5):716-719
The anti-tumor agent gemcitabine hydrochloride, a beta-difluoronucleoside, is remarkably stable in the solid state. In 0.1 N HCI solution at 40 degrees C, deamination of gemcitabine occurs, yielding its uridine analogue. Approximately 86% of the initial gemcitabine remains after 4 weeks under these conditions. Cleavage of the N-glycosidic bond of gemcitabine or conversion to its alpha-anomer in 0.1 N HCI solution is not observed over a 4-week period. However, this work has shown that gemcitabine hydrochloride anomerizes in 0.1 N NaOH at 40 degrees C. Approximately 72% of the initial gemcitabine remains after 4 weeks under the basic conditions used. Uridine hydrolysis products are also formed under these conditions. The anormerization reaction, which is unusual under basic conditions, has been confirmed by characterization of the chromatographically isolated alpha-anomer by NMR and mass spectrometry. A mechanism involving an acyclic intermediate is proposed. 相似文献
82.
We describe an example of a rare benign intranodal haemorrhagic spindle cell tumour (also called intranodal myofibroblastoma), occurring in a lymph node of the right inguinal region of a 53 year-old male patient. This is the first documentation of this tumour in the Danish literature. The lesion presents typically as a unilateral, solitary, painless inguinal lump. The microscopic appearance is characterized by proliferating spindle-shaped cells, interstitial haemorrhage and amianthoid fibers. Differential diagnosis includes primary and secondary lymph node tumours, such as Kaposi's sarcoma; metastatic spindle cell carcinoma; melanoma; neurilemmoma and soft tissue sarcomas. The clinical behaviour of the tumour is benign and local excision is the treatment of choice. 相似文献
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KM McRoberts BP Meloni UM Morgan R Marano N Binz SL Eriandsen SA Halse RC Thompson 《Canadian Metallurgical Quarterly》1996,82(5):711-718
Following the first report of avian Giardia infection in Australia, isolates of the parasite recovered from naturally infected straw-necked ibis (Theskiornis spinicollis) were characterized using median body morphology, scanning electron microscopy, multilocus enzyme electrophoresis, random amplified polymorphic DNA (RAPD), and small subunit ribosomal RNA (SSU-rRNA) analyses. Results were compared with Giardia from other birds and mammals, and the extent of genetic diversity between a range of ibis isolates collected in Western Australia was determined. The ibis isolates of Giardia were genetically relatively homogeneous, which is in contrast to the extensive genetic heterogeneity often displayed by mammalian Giardia isolates. Morphologically, Giardia from ibis were similar to Giardia ardeae although they differed genetically and by the fact that the ibis isolates could not be established in in vitro culture. Sequence data of the DNA coding for the SSU-rRNA found a 96% homology between the ibis isolates from Western Australia and G. ardeae, suggesting that they represent distinct strains of the same species. In contrast, the ibis isolates were genetically and morphologically very different than Giardia duodenalis and Giardia muris from mammals. 相似文献
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SL McElroy CA Soutullo DA Beckman P Taylor PE Keck 《Canadian Metallurgical Quarterly》1998,59(4):203-10; quiz 211
BACKGROUND: The authors' objective was to provide data regarding the demographic, phenomenological, course of illness, associated psychiatric and medical comorbidity, family history, and psychiatric treatment response characteristics of rigorously diagnosed subjects who met DSM-IV criteria for intermittent explosive disorder. METHOD: Twenty-seven subjects meeting DSM-IV criteria for a current or past history of intermittent explosive disorder were given structured diagnostic interviews. The subjects' medical histories, family histories of psychiatric disorders, and responses to psychiatric treatments were also assessed. RESULTS: Most subjects described their intermittent explosive disorder symptoms as very distressing and/or highly problematic. All 27 subjects described aggressive impulses prior to their aggressive acts. Of 24 subjects who were systematically queried, 21 (88%) experienced tension with the impulses; 18 (75%), relief with the aggressive acts; and 11 (48%), pleasure with the acts. Most subjects stated that their aggressive impulses and acts were also associated with affective symptoms, particularly changes in mood and energy level. Twenty-five (93%) subjects had lifetime DSM-IV diagnoses of mood disorders; 13 (48%), substance use disorders; 13 (48%), anxiety disorders; 6 (22%), eating disorders; and 12 (44%), an impulse-control disorder other than intermittent explosive disorder. Subjects also displayed high rates of comorbid migraine headaches. First-degree relatives displayed high rates of mood, substance use, and impulse-control disorders. Twelve (60%) of 20 subjects receiving monotherapy with an antidepressant or a mood stabilizer reported moderate or marked reduction of their aggressive impulses and/or episodes. CONCLUSION: Intermittent explosive disorder appears to be a bona fide impulse-control disorder that may be related to mood disorder and may represent another form of affective spectrum disorder. 相似文献
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EM Perchellet JB Ladesich Y Chen HS Sin DH Hua SL Kraft JP Perchellet 《Canadian Metallurgical Quarterly》1998,9(6):565-576
Methods of both linkage analysis and association analysis may be model-based or model-free. The former are useful for initial exploratory analysis, the latter for more detailed multivariate genometric analysis. Linkage leads to an association, but that association may be solely intrafamilial. Allelic association may be due to pleiotropy, linkage disequilibrium, meiotic drive, selection, or population stratification. Using non-transmitted parental alleles as controls for alleles transmitted to cases, in conjunction with a McNemar-type test, does not detect association in the absence of linkage. Model-based analyses should use models that approximate the complexity of the disease being studied in order to be both robust and powerful. 相似文献
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Sexually transmitted diseases are common complications of pregnancy and may have significant maternal/fetal effects. Knowledge of the symptoms and physical examination features, methods of diagnosis, indications for screening, and appropriate treatment options are essential for obstetric/gynecologic health care providers. 相似文献