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排序方式: 共有3005条查询结果,搜索用时 31 毫秒
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Arnold Criel Gregor Verhoef Robert Vlietinck Cristina Mecucci Johan Billiet Lucienne Michaux Peter Meeus ries Louwagie Angeline Van Orshoven Achiel Van Hoof Mark Boogaerts Herman Van den Berghe & Chris De Wolf-Peeters 《British journal of haematology》1997,97(2):383-391
We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases. In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL. Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival. 相似文献
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H M Frénay C M Vandenbroucke-Grauls M J Molkenboer J Verhoef 《The Journal of hospital infection》1992,22(3):207-215
The purpose of this study was to determine whether patients who become carriers of methicillin-resistant Staphylococcus aureus (MRSA) during their stay in hospital, remain colonized after discharge. Thirty-six patients colonized with MRSA during one of three outbreaks at Utrecht University Hospital (1986-89) were screened 2 or 3 years after they had become carriers. Patients were also interviewed to determine factors contributing to persistent carriage, such as antibiotics, re-admissions to the hospital, presence of skin lesions and chronic diseases. At the same time transmission of MRSA to family members was determined. The epidemic MRSA strain was still found in three patients (8%). One was a cystic fibrosis patient who had had frequent re-admissions to the hospital and had received several course of antibiotic treatment. Both of the other patients had skin lesions: a fistula and a colostomy respectively. None of the 44 family members of the patients was colonized or infected with MRSA. We conclude that long-term MRSA carriage occurs with low frequency and is comparable to persistent carriage of methicillin-sensitive Staphylococcus aureus (MSSA). Transmission of MRSA to healthy individuals in an antibiotic-free environment is a rare event. 相似文献
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Marja Hilska Yrj? Collan Peter J Roberts Jari Ovaska Jyrki K?ssi Hannu Paajanen Matti Laato 《Acta chirurgica》2002,168(2):84-90
OBJECTIVE: To compare the ability of various methods of staging and grading to predict survival in proximal colon cancer. DESIGN: Retrospective study. SETTING: University hospital, Finland. SUBJECTS: 153 patients with primary proximal colon cancer. MAIN OUTCOME MEASURES: Staging by four classification systems, grading by two grading systems, and survival analysis based on Kaplan-Meier survival curves. RESULTS: In all staging systems the survival curves of different stages differed significantly from each other. The modified Dukes' classification was still the best predictor of survival. Grade of tumours had no significant effect on long term survival, but short term survival was affected adversely by the presence of anaplastic tissue. Tumours with no mucin had a worse prognosis than those that produced mucin. All staging methods were superior to either of the histological grading systems tested as prognosticators. Tumour depth correlated with the operator's clinical impression of radicality of operation, and also predicted survival. CONCLUSION: The clinicopathological modified Dukes' staging system was the most powerful prognosticator in proximal colonic cancer and its use in clinical practice should continue. Even a small amount of anaplastic tissue (> or = 5%) had an adverse effect on short term survival. 相似文献
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Safety aspects of non-ionic surfactant vesicles: a toxicity study related to the physicochemical characteristics of non-ionic surfactants. 总被引:1,自引:0,他引:1
H E Hofland J A Bouwstra J C Verhoef G Buckton B Z Chowdry M Ponec H E Junginger 《The Journal of pharmacy and pharmacology》1992,44(4):287-294
Two different toxicity models were used to assess the relationship between the physicochemical properties of non-ionic surfactant vesicles (NSVs), and the safety of these vesicles for topical drug administration. The vesicles used in this study consisted of polyoxyethylene alkyl ethers (CnEOm) in which the number of C atoms (n) varied between 12 and 18 and the number of oxyethylene units (m) between 3 and 7. The physicochemical properties of the vesicles are described in terms of hydrophilic-lipophilic balance (HLB) values, and critical micelle concentrations (CMC), and the rigidity of the bilayers as determined by the gel-liquid transition temperatures and the cholesterol content of the bilayers. The first toxicity model, comprising the measurement of the ciliary beat frequency, is a tool to assess the safety of intranasally applied formulations. Studies using this ciliotoxicity model revealed that by increasing the length of the alkyl chain of the surfactant, a decrease in toxicity was observed. The opposite correlation was found if the length of the polyoxyethylene headgroup was increased. Furthermore, it was observed that gel-state vesicles produce less of an effect on the ciliary beat frequency than liquid state vesicles. The second toxicity model, comprising the determination of cell proliferation of human keratinocytes, is a method to assess skin irritancy. In contrast to the ciliotoxicity model the length of the polyoxyethylene headgroup and of the alkyl chains did not seem to have an effect on the safety of the vesicles.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Depression-executive dysfunction syndrome in stroke patients. 总被引:6,自引:0,他引:6
Risto Vataja Tarja Pohjasvaara Riitta M?ntyl? Raija Ylikoski Maarit Leskel? Hely Kalska Marja Hietanen Hannu Juhani Aronen Oili Salonen Markku Kaste Antero Lepp?vuori Timo Erkinjuntti 《The American journal of geriatric psychiatry》2005,13(2):99-107
OBJECTIVE: It has been suggested that executive dysfunction could be the core defect in patients with geriatric or vascular depression, and that this depression-dysexecutive syndrome (DES) might be related to frontal-subcortical circuit dysfunction. The authors tested this hypothesis in 158 poststroke patients, of whom 21 had both depression and executive dysfunction. Methods: In this cross-sectional cohort study, a neurological, psychiatric, and neuropsychological examination was carried out 3 months after ischemic stroke, and brain infarcts, white-matter changes, and brain atrophy were recorded by MRI. RESULTS: The 21 patients with DES had significantly more brain infarcts affecting their frontal-subcortical circuit structures than the 137 patients without DES, or the 41 patients with depression but without executive dysfunction. Patients with DES also had more severe depressive symptoms and worse psychosocial functioning, and they coped less well in complex activities of daily living. CONCLUSIONS: DES is a valid concept and may define a subgroup of poststroke patients with frontal-subcortical pathology and with distinct prognosis and treatment options. 相似文献
10.
Thomas Zeiler MD Antti Taivainen MD PhD Marja Rytkönen PhD Jaakko Rautiainen MSc Henry Karjalainen PhD Rauno Mäntjärvi MD PhD Leena Tuomisto MD PhD Tuomas Virtanen MD PhD 《The Journal of allergy and clinical immunology》1997,100(6):721-727
Background: Lately, renewed interest has arisen in the new forms of allergen immunotherapy because they may offer alternatives for drug treatment. Objective: The purpose of this study was to develop a well-characterized preparation of the main respiratory cow dander allergen, Bos d 2, with attenuated allergenic activity. Methods: The immunologic characteristics of Bos d 2 preparations were studied by indirect IgE ELISA, ELISA inhibition, Western blotting, histamine release, skin prick tests, and the proliferation tests of allergen-specific T-cell clones. Results: The complete recombinant Bos d 2 was observed to bind effectively, IgE of cow-allergic patients in indirect ELISA. In other experiments, the IgE-binding capacity of recombinant Bos d 2 proved to be lower compared with native Bos d 2. When the two overlapping recombinant fragments of Bos d 2 (corresponding amino acids 1-131 and 81-172, respectively) covering the whole molecule were compared with the complete recombinant Bos d 2 with several methods, only a low level of residual reactivity was observed. For example, recombinant fragments could not bind antibody at all in ELISA inhibition tests retaining, however, some reactivity in skin prick tests. In contrast, the fragments were able to stimulate vigorously Bos d 2-specific T-cell clones. Conclusion: The approach we have taken may offer a simple and reproducible way to produce hypoallergenic preparations for immunotherapy, circumventing simultaneously some of the problems of other experimental methods such as individual T-cell epitope recognition in peptide-based immunotherapy. (J Allergy Clin Immunol 1997;100:721-7.) 相似文献