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1.
Between 1992 and 1995 a series of studies was undertaken to assess the long-term suitability of pyrethroid-impregnated bednets (PIBs) for malaria control in Afghan refugee communities in two villages in North-West Frontier Province, Pakistan. During 1992, 86% of bednet owners volunteered to have their bednets re-impregnated, and a further 15% of families purchased nets at two-thirds of cost price. From 1992 onwards, 27% of the villagers returned to Afghanistan, and annual house spraying campaigns were introduced to protect those still resident but sleeping without bednets. Within 3 years, these campaigns, together with PIBs, reduced the annual incidence of malaria by 87%, from 597 to 78 cases per 1000 population. Nevertheless, 65% of resident families continued to re-impregnate their nets annually with permethrin. To assess whether PIBs were still being used and were still protective, in view of these reduced transmission rates, we carried out a case--control study in 1994 on febrile or otherwise symptomatic patients presenting at village health centres. Comparison of the slide-positivity rates of PIB users and those without bednets showed that regular usage reduced the odds of contracting falciparum and vivax malaria to 0.22 (95% confidence interval (CI): 0.09-0.55) and 0.31 (95% CI: 0.19-0.51), respectively. There was no evidence of a sex- or age-bias in bednet use or in protective effect. The results indicate that a community-based PIB programme is an appropriate malaria control measure in areas where management or security problems make traditional house-spraying campaigns impossible. A relevant finding for those involved in the monitoring of bednet distribution projects is that the local coverage of bednets and the local impact on malaria, even when introduced to remote areas, can be estimated very cheaply by health centre microscopists who simply catalogue blood film diagnoses according to patients'' bednet use practices.  相似文献   
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PURPOSE: Combination chemotherapy with irinotecan (CPT-11; 50 mg/kg/week x 4 intravenously), followed 24 hour later by 5-fluorouracil (50 mg/kg/week x 4 intravenously), results in 10 and 100% cure rates of animals bearing human head and neck squamous cell carcinoma xenografts A253 and FaDu, respectively. A253 consists of 30% well-differentiated and avascular and 70% poorly differentiated regions with low microvessel density (10/x400), whereas FaDu is uniformly poorly differentiated with higher microvessel density (19/x400). Studies were carried out for determining the role of well-differentiated and avascular regions in drug resistance in A253 and detection of such regions with noninvasive functional magnetic resonance (fMR) imaging. EXPERIMENTAL DESIGN: Tumors were harvested for histopathologic evaluation and immunohistochemistry (CD31, CD34; differentiation marker: involucrin; hypoxia markers: carbonic anhydrase IX, pimonidazole; vascular endothelial factor (VEGF) and Ki67) immediately after fMR imaging following the 3rd dose of chemotherapy. High-performance liquid chromatography determination of intratumoral drug concentration of 7-ethyl-10-hydroxyl-camptothecin and autoradiography with (14)C-labeled CPT-11 was done 2 hours after CPT-11 administration. RESULTS: Although A253 xenografts showed three times higher concentration of 7-ethyl-10-hydroxyl-camptothecin, FaDu was more responsive to therapy. After therapy, A253 tumor consisted mostly (approximately 80%) of well-differentiated regions (positive for involucrin) lacking microvessels with a hypoxic rim (positive for carbonic anhydrase IX and pimonidazole) containing few proliferating (Ki67 positive) poorly differentiated cells. Autoradiography revealed that well-differentiated A253 tumor regions showed 5-fold lower (14)C-labeled CPT-11 concentrations compared with poorly differentiated areas (P < 0.001). Blood oxygen level dependant fMR imaging was able to noninvasively distinguish the hypoxic and well-vascularized regions within the tumors. CONCLUSION: Avascular-differentiated regions in squamous cell carcinoma offer sanctuary to some hypoxic but viable tumor cells (carbonic anhydrase IX and Ki67 positive) that escape therapy because of limited drug delivery. This study provides direct evidence that because of a specific histologic structure, avascular, well-differentiated hypoxic regions in tumors exhibit low drug uptake and represent a unique form of drug resistance.  相似文献   
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Forty-five patients with metastatic breast cancer without clinically evident disease were treated with thiotepa 750 mg/m2, mitoxantrone 40 mg/m2 and carboplatin 1000 mg/m2 followed by stem cell transplantation to determine the safety and efficacy of CD34+ selection of peripheral blood stem cells. Of these, 15 patients' (group I) stem cells were processed through Baxter Isolex 300 device for CD34+ selection, whereas 30 patients (group II) received unmanipulated stem cells. Toxicity, progression-free survival and survival were compared between these two groups. There was no difference in transfusion requirements, white cell count and platelet recovery and non-hematologic toxicity between the two groups. The survival of patients in group I was 27 months compared to 38 months in group II (P = 0.8). The progression-free survival was 12 months and 13.5 months for group I and group II patients, respectively (P = 0.6). Our results indicate that while there is no adverse effect, there is also no significant advantage of CD34+ selection in terms of progression-free survival and survival in patients with metastatic breast cancer without clinically evident disease. Bone Marrow Transplantation (2000).  相似文献   
5.
ContextPatients with metastatic lung cancer and their spousal caregivers are at high risk of psychological symptoms. Mindfulness may improve psychological symptoms via spiritual well-being (SW); yet, this mediation model has not been examined in a dyadic context.ObjectivesWe examined the mediating role of two dimensions of SW (meaning/peace and faith) in the mindfulness-symptoms link in Stage IV lung cancer patients and their spousal caregivers.MethodsWe examined the actor-partner interdependence model of mediation using multivariate multilevel modeling with 78 couples. Four actor-partner interdependence model of mediation analyses were conducted to examine one predictor (mindfulness) × two mediators (meaning/peace and faith) × two psychological symptoms (depressive symptoms and cancer distress). We also tested four alternative models in which mindfulness mediates the associations between SW and psychological symptoms.ResultsThe alternative model (SW → mindfulness → psychological symptoms) was preferred than the original model (mindfulness → SW → psychological symptoms). For patients, meaning/peace was directly associated with their own psychological symptoms, whereas faith was only indirectly associated with their own psychological symptoms via mindfulness. For spouses, meaning/peace was both directly and indirectly associated with their own psychological symptoms, whereas faith was only directly associated with their own depressive symptoms (but not cancer distress). Moreover, spouses' faith was indirectly associated with patients' psychological symptoms through patients' mindfulness.ConclusionSW is associated with patients' and spouses' psychological symptoms both directly and indirectly through mindfulness. Thus, interventions that target SW, particularly meaning and peace, along with mindfulness may be beneficial to the psychological management of patients facing a terminal disease and their spousal caregivers.  相似文献   
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The nucleoside analogue decitabine can deplete the epigenetic regulator DNA methyltransferase 1 (DNMT1), an effect that occurs, and is saturated at, low concentrations/doses. A reason to pursue this molecular-targeted effect instead of the DNA damage/cytotoxicity produced with high concentrations/doses, is that non-cytotoxic DNMT1-depletion can cytoreduce even p53-null myeloid malignancies while sparing normal haematopoiesis. We thus identified minimum doses of decitabine (0·1–0·2 mg/kg) that deplete DNMT1 without off-target anti-metabolite effects/cytotoxicity, and then administered these well-tolerated doses frequently 1–2X/week to increase S-phase dependent DNMT1-depletion, and used a Myeloid Malignancy Registry to evaluate long-term outcomes in 69 patients treated this way. Consistent with the scientific rationale, treatment was well-tolerated and durable responses were produced (~40%) in genetically heterogeneous disease and the very elderly.  相似文献   
8.
T-cell large granular lymphocytic leukaemia (T-LGLL) is a chronic clonal lymphoproliferative disorder of cytotoxic T lymphocytes which commonly occurs in older patients and is often associated with autoimmune diseases. Among 246 patients with T-LGLL seen at our institution over the last 10 years, we encountered 15 cases following solid organ or haematopoietic stem cell transplantation. Here, we studied the clinical characterization of these cases and compared them to de novo T-LGLL. This experience represented a clear picture of the intricate nature of the disease manifestation and the complexities of several immune mechanisms triggering the clonal expansion.  相似文献   
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Complete or partial fingers are the most commonly encountered forms of partial hand losses. Though finger amputations are commonly due to traumatic injuries, digit loss may also be attributed to congenital malformations and disease. Irrespective of the etiology, the loss of a finger has a considerable functional and psychological impact on an individual. In order to alleviate these problems, partial or complete finger prosthesis may be fabricated. This clinical report portrays a method to fabricate silicone rubber prosthesis for a patient who has a partial finger loss caused due to trauma.  相似文献   
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