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991.
In a Danish population-based non-Hodgkin's lymphoma registry, 2687 newly diagnosed patients were registered from 1983 to 1992. 39 had testicular involvement (TL) (incidence 0.26/10(5)/year). Median age was 71 years. 24 cases had localised and 15 had disseminated disease. Histologically, all cases were diffuse (65% diffuse centroblastic type). Of the 27 tested, 11% were of T- and 89% of B-immunophenotype. In localised cases, where surgery was supplemented by combination chemotherapy (CCT), the relapse rate was 15.4%. The relapse rate for cases with localised disease treated with other regimens (orchiectomy and/or radiotherapy) was 63.6% (P < 0.05). Median relapse-free survival was 28 and 14 months, respectively. Overall 5-year survival for all cases was 17%. Adverse prognostic factors at the univariate level were stage IV, constitutional symptoms, serum lactic dehydrogenase elevation and performance score (WHO 3-4). It is suggested that the treatment of stage IE/IIE TL should include early CCT and CNS prophylaxis. 相似文献
992.
993.
S G?r?g M Babják G Balogh J Brlik F Dravecz M Gazdag P Horváth A Laukó K Varga 《Canadian Metallurgical Quarterly》1998,18(4-5):511-525
Due to the varied reactions leading to the 3-oxo group in steroids and the reactivity of its environment, a large number of impurities related to this group are formed during the reaction steps and the degradation studies. In this paper the experiences from the authors laboratory with the 3-oxo-related impurities in 19-nor-4-ene-3-oxosteroids (norgestrel, norethisterone, nandrolone, its esters and Nestorone) as well as corticosteroids (prednisolone, mazipredone, etc) are presented. The impurities include saturated 3-ones, 1-ene-3-ones, 5(10)-ene-3-ones, 3-deoxo and 3-ethinyl-3,5-diene derivatives, 6-ene, 8(14)-ene, 6,8(14)-diene, 6-hydroxy (alpha and beta), 10beta-hydroxy and 6-one derivatives in 4-ene-3-oxosteroids and 8(9)-ene, 9(11)-ene, 11alpha-hydroxy, 11-oxo and 4-ene-3-one derivatives in 11beta-hydroxy-1,4-diene-3-oxosteroids. The chromatographic, spectroscopic and hyphenated techniques used in this study include TLC, GC, HPLC with diode array UV detector, GC-MS, LC-MS and NMR methods. 相似文献
994.
The neuropsychological characteristics of frontal lobe epilepsy have rarely been reported, with neuropsychological indicators usually being related to subjects with other forms of neurological damage. In this study we assessed the performance of 74 subjects with frontal lobe epilepsy (42 with left, 32 with right frontal epileptic foci) on a series of measures thought to be sensitive to frontal lobe dysfunction and compared to 57 subjects with temporal lobe epilepsy (31 with left, 26 with right epileptic foci). The results indicated a number of measures that could be considered sensitive to frontal lobe epileptic dysfunction. However, the pattern of results did not indicate consistent deficits to be associated with frontal lobe epileptic dysfunction. There are a number of unique factors associated with epilepsy that need to be considered, and these may account for the variable pattern of results obtained. In particular, the rapid propagation of frontal lobe seizures both bilaterally and to other cortical regions has to be considered. 相似文献
995.
OBJECTIVE: To determine whether a significant association occurs between the presence of various periodontal diseases and recoverable infectious HIV-I in the saliva of injecting drug users. DESIGN: Five hundred and fifty-one injecting drug users were recruited from various programs associated with the Beth Israel Medical Center. Examiners were 'blinded' to the subject's HIV-I serostatus. A socio-economic and risk factors' survey was conducted and a complete oral examination, including periodontal disease indices was performed. Whole saliva and blood were collected for virus culture. MAIN OUTCOME MEASUREMENTS: Recovery of infectious HIV-I in saliva related to presence of periodontal diseases. RESULTS: Those HIV-I seropositive subjects with periodontal diseases did not differ from those HIV-I seropositive subjects without periodontal disease in mean age and immune status. Less than 1% of the HIV-I seropositive subjects had cultivable HIV-I in their saliva while it was present in 78% of PBMCs and 35% of the sera. There was no significant association between infectious HIV-I in saliva, serum, or PBMCs and any of the various periodontal diseases. CONCLUSIONS: The presence of periodontal disease in HIV-I seropositive injecting drug users does not appear to be a potential risk factor for infectious HIV-I in saliva, probably due to the various anti-viral components of saliva. 相似文献
996.
Epinephrine increased outflow facility and cyclic AMP in the in vitro perfused human anterior segment with a maximal facility increase of 44% occurring at approximately 2 x 10(-5) M. Cyclic AMP measured in the perfusate from anterior segments increased by 12-14 fold after administration of 10(-5) M epinephrine. Both the facility increase and cyclic AMP rise were blocked by the beta-2 selective antagonist, ICI118,551. While there was a correlation between the facility increase and elevation in cyclic AMP levels, the rise in cyclic AMP preceded the facility increase by about 1 hour, suggesting that the ultimate effect of epinephrine involved a rather slow event such as synthesis and release of prostaglandins or protein synthesis. Subsequent perfusion studies showed that very large concentrations of indomethacin were necessary to block the outflow facility effect of epinephrine, suggesting that prostaglandin synthesis did not underlie the facility effect in this system. However, 5 x 10(-5) M cyclohexamide blocked the effect on outflow facility of both epinephrine and forskolin, but did not block the rise in cyclic AMP. These studies suggest that protein synthesis may play a role in the epinephrine-induced facility increase at some point beyond the second messenger level. 相似文献
997.
998.
999.
1000.
B Springer L Stockman K Teschner GD Roberts EC B?ttger 《Canadian Metallurgical Quarterly》1996,34(2):296-303
Previous studies have indicated that the conventional tests used for the identification of mycobacteria may (i) frequently result in erroneous identification and (ii) underestimate the diversity within the genus Mycobacterium. To address this issue in a more systematic fashion, a study comparing phenotypic and molecular methods for the identification of mycobacteria was initiated. Focus was given to isolates which were difficult to identify to species level and which yielded inconclusive results by conventional tests performed under day-to-day routine laboratory conditions. Traditional methods included growth rate, colonial morphology, pigmentation, biochemical profiles, and gas-liquid chromatography of short-chain fatty acids. Molecular identification was done by PCR-mediated partial sequence analysis of the gene encoding the 16S rRNA. A total of 34 isolates was included in this study; 13 of the isolates corresponded to established species, and 21 isolates corresponded to previously uncharacterized taxa. For five isolates, phenotypic and molecular analyses gave identical results. For five isolates, minor discrepancies were present; four isolates remained unidentified after biochemical testing. For 20 isolates, major discrepancies between traditional and molecular typing methods were observed. Retrospective analysis of the data revealed that the discrepant results were without exception due to erroneous biochemical test results or interpretations. In particular, phenotypic identification schemes were compromised with regard to the recognition of previously undescribed taxa. We conclude that molecular typing by 16S rRNA sequence determination is not only more rapid (12 to 36 h versus 4 to 8 weeks) but also more accurate than traditional typing. 相似文献