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991.
The Brighton Collaboration: addressing the need for standardized case definitions of adverse events following immunization (AEFI) 总被引:3,自引:0,他引:3
Bonhoeffer J Kohl K Chen R Duclos P Heijbel H Heininger U Jefferson T Loupi E 《Vaccine》2002,21(3-4):298-302
To further scientific progress of immunization safety, comparability of data from clinical trials and surveillance systems is essential. Comparability requires the availability of standardized case definitions for adverse events following immunization (AEFI) and guidelines for case determination, recording and data presentation. METHOD: International collaborative working groups, consisting of professional volunteers from developed and developing countries, conduct systematic literature reviews to develop 50-100 AEFI definitions. Case definitions are finalized after a comment period by a reference group consisting of organizations concerned with immunization safety, and will be disseminated via the world-wide-web and other means for free world-wide use. RESULTS: Literature reviews yielded substantial diversity in data collection and presentation. We have developed standardized case definitions together with guidelines for use in clinical trials and surveillance systems. CONCLUSIONS: Diversity in safety methods leads to considerable loss of scientific information. We have built the necessary international network of currently about 300 participants from patient care, public health, scientific, pharmaceutical, regulatory and professional organizations to develop and assess standardized AEFI case definitions and guidelines. Evaluation studies, global implementation, ongoing definition development and a continuously growing network will be essential for the success of the collaboration. 相似文献
992.
Ethnic differences in social correlates of diet 总被引:2,自引:0,他引:2
Cullen KW Baranowski T Owens E de MC Rittenberry L Olvera N Resnicow K 《Health education research》2002,17(1):7-18
Little is known about whether culture influences social correlates of dietary behaviors. Questionnaires on parent- and child-reported family and peer influences on children's fruit, juice and vegetable consumption were analyzed for ethnic group differences in responses. Grade 4-6 students completed the questionnaires in the classroom and their parents completed telephone or in-home interviews. Analyses of variance across ethnic categories and chi2 analysis of differences in ethnic group composition between clusters of scales were conducted. Few ethnic group differences were detected, suggesting substantial commonality among respondents. Ethnic differences might be accommodated by interventions tailored to particular behaviors among ethnic groups. 相似文献
993.
Xu KT 《Social science & medicine (1982)》2002,54(1):133-146
This paper studied smoking behavior in the context of the interactions among health, smoking, exercise and seeking medical care using a microeconomic model. Based on a dynamic optimal choice theory, a simultaneous equation system was used in the empirical estimation. This study found that smokers with longer smoking history tend to have extra incentives to maintain or improve their health. It was found that they tend to use more medical services and to be more active in exercise than smokers with shorter smoking history. Health status nonlinearly affects smoking decisions. Quitting incentives can be "curative" or "preventive", depending on one's health status. Light smokers' addiction is qualitatively and quantitatively different from heavy smokers'. 相似文献
994.
995.
996.
Presence of active gelatinases in endometrial carcinoma and correlation of matrix metalloproteinase expression with increasing tumor grade and invasion 总被引:23,自引:0,他引:23
Di Nezza LA Misajon A Zhang J Jobling T Quinn MA Ostör AG Nie G Lopata A Salamonsen LA 《Cancer》2002,94(5):1466-1475
BACKGROUND: The actions of the extracellular-matrix degrading enzymes, matrix metalloproteinases (MMPs), are implicated in tumorigenesis. The cellular localization of MMP-2, MMP-9, membrane type 1 (MT1)-MMP, tissue inhibitors of metalloproteinases (TIMPs) 1-3, and the presence of active gelatinases were investigated in endometrial carcinoma. METHODS: Endometrial carcinomas were grouped according to histologic grade (Grades 1-3), depth of myometrial invasion (0, < 50%, > 50%) and the presence of vascular/lymphatic invasion. Twenty-nine endometrial carcinoma biopsies were investigated immunohistochemically to determine the tissue localization of MMP-2 (gelatinase A), MMP-9 (gelatinase B), MT1-MMP, and TIMPs 1-3. In situ hybridization was performed to localize MMP-2 and MMP-9 mRNA. The presence of active gelatinases was assessed using in situ zymography. RESULTS: Epithelial tumor cells were the main site of MMP-2, MMP-9, and MT1-MMP protein. Variable stromal cell localization was also observed, particularly in areas adjacent to tumor nests. Semiquantitative analysis revealed increases in MMP-9 and MMP-2 but not MT1-MMP staining scores in tumor epithelial cells in the transition from histologic Grade 1 to Grades 2 and 3. Matrix metalloproteinase-9 and MT1-MMP staining scores in tumor cells were significantly associated with the presence of myometrial invasion and vascular/lymphatic invasion, while MMP-2 did not correlate with these factors. In addition, MT1-MMP was co-localized with MMP-2, supporting its role in the activation of proMMP-2. Tumor cells from all histologic grades stained intensely for TIMP-2 and TIMP-3 proteins, while variable stromal staining was observed. In Grade 1 carcinomas TIMP-1 was predominantly immunolocalized to the stromal compartment with variable tumor cell localization being observed in Grades 2 and 3 carcinomas. Matrix metalloproteinase-9 and MMP-2 mRNAs were predominantly observed in tumor epithelial cells as well as in the stroma to varying degrees. In situ zymography revealed active forms of gelatinases at the cellular surface and in association with tumor epithelial cells within endometrial carcinoma tissues. CONCLUSIONS: These data suggest that increasing expression of MMPs and endometrial carcinoma progression are closely related. Active gelatinases are present in endometrial carcinoma, resulting in alterations to the microenvironment that promote tumor invasion and metastasis. 相似文献
997.
Markovic SN Suman VJ Vukov AM Fitch TR Hillman DW Adjei AA Alberts SR Kaur JS Braich TA Leitch JM Creagan ET 《American journal of clinical oncology》2002,25(3):308-312
KW-2189, a semisynthetic duocarmycine antibiotic has been shown to exert antiproliferative effects against human tumor cell lines in vitro and animal tumor models in vivo. Phase I studies identified myelosuppression as the most noteworthy adverse effect. Presented are two concurrent phase II studies assessing the antitumor and toxicity profile of KW-2189 in metastatic melanoma patients. One of the studies accrued patients with a history of prior melanoma therapy and the other accrued patients without a history of prior melanoma therapy. KW-2189 was administered at 0.4 mg/m2 to previously treated patients and 0.5 mg/m2 to the previously untreated. Treatment was administered intravenously on day 1 of a 6-week cycle. Thirty previously untreated and 15 previously treated patients were accrued. The toxicity profiles of the both groups of patients were similar. Of the 15 previously treated patients, 8 completed once cycle of treatment, 2 completed 2 cycles, and 5 completed 3 cycles. Dose modification for neutropenia/ thrombocytopenia was necessary in six patients. Among the previously untreated cohort (30 patients), 16 completed 1 cycle, 5 completed 2 cycles, 4 completed 3 cycles, 3 completed 4 cycles, and 2 completed 6 cycles. Doses were modified (neutropenia or thrombocytopenia) in 11 patients. None of the 15 previously treated patients responded to therapy. Four patients remained stable during two cycles. Five of the previously untreated patients achieved a partial remission/regression. Response duration ranged from 2.8 to 16.6 months. Overall objective response rate was 17%. Regarding survival, one previously treated patient is still alive 2.9 years after study entry, and three previously untreated patients are still alive 1.6, 2.3, and 2.9 years after study entry. The 1-year survival rate for previously treated patients is 27% and for the untreated patients is 23%. In summary, the lack of significant antitumor activity of KW-2189 and its associated toxicity suggest that further testing of this regimen in patients with stage IV melanoma is not warranted. 相似文献
998.
Targeted disruption of Dkc1, the gene mutated in X-linked dyskeratosis congenita,causes embryonic lethality in mice 总被引:5,自引:0,他引:5
Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome associated with increased cancer susceptibility. The X-linked form is due to mutations in the DKC1 gene encoding dyskerin, a nucleolar protein predicted to be involved in rRNA processing and associated with the telomerase complex. Available evidence suggests the pathology of DC is due to telomerase defects. We have used the inducible Cre/loxP system to produce deletions in the murine Dkc1 gene in early embryogenesis. A large deletion lacking exons 12-15 and a small deletion lacking only the last exon, were produced. We found both deletions showed a parent-of-origin effect with 100% embryonic lethality when the mutation occurred on the maternal Dkc1. Embryonic analysis at day E7.5 and E9.5 showed no male embryos carrying either deletion whereas females with maternally derived deletions died around day E9.5, with degeneration of the extra embryonic tissue, in which the paternal X-chromosome is inactivated. Female mice carrying the deletion in the paternally derived Dkc1 show extreme skewing of X-inactivation with the wild type X-chromosome active in all cells. Since mice with no telomerase are viable in the first generations the lethality we observe is unlikely to be due to the effects of mutated dyskerin on telomerase activity. 相似文献
999.
Oinonen R Jantunen E Itälä M Lehtinen T Kuittinen O Franssila K Wiklund T Elonen E 《Leukemia & lymphoma》2002,43(6):1229-1237
High-dose therapy followed by autologous stem cell transplantation (ASCT) has been considered a potential treatment approach in order to improve the poor prognosis in mantle cell lymphoma (MCL), but its role has not yet been clearly established. We analyzed retrospectively the outcome and prognostic factors in 48 consecutive patients with MCL scheduled for ASCT in five transplant centers. In 14 patients (29%), a sufficient amount of stem cells could not be collected. Mobilization failure was associated with female sex, blastoid cytology, and low hemoglobin level. Altogether 35 patients underwent ASCT, 24 patients as part of the first-line treatment and 11 patients later. After transplantation 28 patients (80%) remained in or achieved remission. Two patients died of transplant-related complications. During the median follow-up time of 38 months, nine patients have relapsed. The median event-free survival (EFS) was 39 months. Age over 60 years and elevated C-reactive protein level at diagnosis were associated with poorer outcome after transelantation. ASCT is an effective treatment in MCL with a high response rate and a longer survival than seen in conventionally treated patients. However, no plateau was seen in the EFS curve after ASCT. Whether cure Can be achieved in a proportion of patients with ASCT is currently unknown and should be studied in larger patient series with a longer follow-up. 相似文献
1000.
Pickles T Agranovich A Berthelet E Duncan GG Keyes M Kwan W McKenzie MR Morris WJ;British Columbia Cancer Agency Prostate Cohort Outcomes Initiative 《Cancer》2002,94(2):362-367
BACKGROUND: This study was conducted to describe the rate and completeness of the recovery of testosterone production following prolonged temporary androgen ablative therapy in men with prostate carcinoma undergoing curative radiation therapy. METHODS: Two-hundred and sixty-seven men treated with between 3 months and 3 years of adjuvant androgen ablation (AA) were followed at 6-month intervals following cessation of their androgen deprivation therapy. A comparative group of 518 men not undergoing AA were also followed. RESULTS: Drugs used included low dose cyproterone/stilboestrol (CPA/DES) in combination (56%) and 1 month depot (18%) and 3 month depot (25%) leutinizing hormone releasing hormone agonist (LHRHa). Seventy-nine percent of men in the current study recovered normal testosterone levels (10nmol/L), and 93% recovered levels of at least 5nmol/L. In comparison, men who had never received androgen ablative therapy showed a fall of testosterone, with 17% having sub-normal levels after 3 years. Median time to testosterone recovery was 10 months. Factors associated on multivariate analysis with delayed testosterone recovery included advanced age (P = 0.008), low pre-therapy testosterone (P = 0.04), and the use of 3 month LHRHa preparations as compared with CPA/DES (P = 0.002) or 1 month LHRHa preparations (P = 0.015). The duration of drug use was not significantly associated with time to testosterone recovery. CONCLUSIONS: Long-acting LHRHa preparations appear to have a more prolonged action than previously supposed. Most men treated for up to 2 years recover normal testosterone levels after cessation of adjuvant androgen ablation, and the limited data available in the current study on patients treated for 3 years also suggests most will recover. 相似文献