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991.
Because no consensus exists regarding recommendable dose levels for irinotecan, an intrapatient dose escalation phase I-II study was initiated in previously treated patients with colorectal cancer. Survival was a secondary endpoint. Thirty-five consecutive patients with progressive disease after 5-fluorouracil-based chemotherapy were enrolled to receive irinotecan starting from 250 mg/m2/3 weeks and rising to currently used therapeutic doses. In total, 162 cycles were administered. The median tolerable dose was 250 mg/m2. Twelve patients (34%) were unable to tolerate doses greater than 250 mg/m2, 10 patients (28%) presented toxicity at 250 mg/m2 and 2 patients tolerated only 200 mg/m2. Three patients (9%) had partial response. The major adverse reactions were grade III-IV diarrhea, grade II-III nausea/vomiting, grade II-III neutropenia, and grade II-III anaemia in 28%, 48%, 11%, and 17% of the patients, respectively. Median survival time and time to progression were 8 and 3 months, respectively. The current irinotecan dose of 350 mg/m2/3 weeks appears unacceptably toxic and, hence, a lower dose needs to be considered. The response rates obtained are similar to the results observed in phase III studies, and its activity appears not to be adversely affected with this treatment scheme.  相似文献   
992.
Chlorinated aromatic contaminants are active in carcinogenic processes within the skin and may have the potential to modulate ultraviolet radiation (UV)-induced skin carcinogenesis. Exposure to a complex environmental PCB/PCDD/PCDF mixture (polychlorinated biphenyls/polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans) during the irradiation phase of photocarcinogenesis was associated with significant (P < or = 0.001) reductions in papilloma incidence and squamous cell carcinoma multiplicity at irradiated skin sites. This protective effect was associated with significantly (P < 0.0001) reduced chronic epidermal thickening in UV and contaminant-exposed mice compared with mice exposed to UV only. Contaminant exposure was also associated with increased UV absorbance of skin methanol extracts implying a sunscreen-like effect.  相似文献   
993.
The purpose of this study was to assess the usefulness of thallium-201 (Tl-201) single-photon emission-computed tomography (SPECT) scintimammography to differentiate benign from malignant breast masses in 32 female Taiwanese patients with indeterminate mammographic probability of malignancy because of mammographically dense breasts. All breast masses were removed, and final histopathological diagnoses were obtained in all cases. The results showed that thallium-201 SPECT scintimammography findings were true-positive in 22 cases, false-positive in 1 case, true-negative in 7 cases, and false-negative in 2 cases. The diagnostic sensitivity, specificity, and accuracy were 91.7%, 87.5%, and 90.6%, respectively, for detecting breast cancer in mammographically dense breasts. In conclusion, thallium-201 SPECT scintimammography is a useful tool for differentiating benign from malignant breast masses in patients with indeterminate mammograms because of mammographically dense breasts.  相似文献   
994.
995.
Employing quantitative and qualitative measures, online and paper versions, we tested Kreps's (1988) relational health communication model by examining relations among social support, communication competence, and perceived stress in a study of well-elders, elderly individuals with cancer, and their lay caregivers (N = 76). Grounding the qualitative part of the study in the narrative paradigm (Fisher, 1984), we used the critical incident technique (Flanagan, 1954) to collect participant narratives focusing on positive and negative expressions of social support. The results indicated partial support for the relational health communication model. In particular, participants who were more communicatively competent were found to have lower levels of perceived stress, and they were more satisfied with the support offered by members of their support network. In addition, the critical incidents revealed that participants received significantly more emotional and esteem support from their network than other social support types. Key limitations and future directions are also identified.  相似文献   
996.
997.
998.
BACKGROUND: The recent transposition of the Biocides Directive by means of Royal Decree 1054/2002 involves a substantial change in different Environmental Health-related aspects. To assess the impact of these changes, an analysis of the current situation is provided, based on which the consequences of the implementation of this Directive in Spain may be assessed, in addition to setting out the main aspects which must be analyzed with a view to a Biocides Registry being put into place in accordance with the aforementioned Royal Decree. METHODS: The analysis was made based on the data included in the Spanish Ministry of Health and Consumer Affairs related to aerosol insect sprays registered for Household Use. Aerosols were chosen as a result of their being the type most numerous on the market for household use. RESULTS: The formulation of these aerosols includes 25 insecticides, 1 disinfectant and 2 synergizers. A majority of the 298 aerosol insect sprays include some pyretroid in their composition, by itself or combined with some other insecticide, disinfectant and/or synergizing compound. Most of these biocides are a mixture of active substances. CONCLUSIONS: Based on the analysis made, the need of setting out new procedures for assessing the effectiveness of the formulas prepared for the use in question (design of standardized testing protocols, assessment of effectiveness on the different pest species, the effect of the mixture of active ingredients, safety timeframes, ...), in addition to the aspects related to toxicology; ecotoxicology or physicochemical characteristics.  相似文献   
999.
Cystic lesions of the pancreas are infrequent, estimated at only some 1% of all pancreatic tumours and at some 10% of all pancreatic cysts. The pre-operational diagnosis is important for a suitable treatment, with valuable radiological techniques available today such as ultrasound, computerised tomography and magnetic resonance. In spite of this we have to accept that we are facing a group of tumours whose diagnosis is difficult, due to the great variety of cellular types existing within them.  相似文献   
1000.
BACKGROUND: On 17 November 2001, less than 900 days after the end of one of the largest population displacements since 1945, the, Kosovo electorate voted for their new self-government. An Assembly was formed in 2001 and a Health Minister, Dr Numan Balic, appointed in March 2002. He has inherited a health service that still reels from many years of neglect while it struggles to implement an ambitious health reform programme. METHODS: An analysis of UNMIK Regulations and available grey literature within Kosovo has formed the basis of material for this article. In addition, the authors collected, by informal interview, the opinions of international and Kosovars actively employed within the health sector. The authors would wish to acknowledge the contribution of Dr Hannu Vuori, Principal International Officer, Ministry of Health, Kosovo for his insight and suggestions. RESULTS: The analysis reveals that the current health system is inequitable and inefficient. The health sector reforms initiated by the international community are desperately needed: it is purported that one-in-three Kosovars cannot afford to access health care when ill. However, the combined legacy of neglect, the current status of the health service and the new Assembly regulations present significant challenges to health reform. CONCLUSIONS: Under the gaze of the newly formed Assembly, as well as the watchful eye of the United Nations Interim Administrative Mission in Kosovo, the Minister will take on the arduous responsibility of governing the Kosovo health sector. In any context implementing reform is difficult, in Kosovo it may be even more so and the international community should not exclusively focus on other world-trouble spots when many challenges remain to be addressed.  相似文献   
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