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71.
72.
Radioactivity in the soil of a tea garden in the Fatickchari area in Chittagong, Bangladesh, was measured using a high-resolution HPGe detector. The soil samples were collected from depths of up to 20 cm beneath the soil surface. The activity concentrations of naturally occurring 238U and 232Th were observed to be in the range of 27 ± 7 to 53 ± 8 Bq kg−1 and 36 ± 11 to 72 ± 11 Bq kg−1, respectively. The activity concentration of 40K ranged from 201 ± 78 to 672 ± 81 Bq kg−1, and the highest activity of fallout 137Cs observed was 10 ± 1 Bq kg−1. The average activity concentration observed for 238U was 39 ± 8 Bq kg−1, for 232Th was 57 ± 11 Bq kg−1, for 40K was 384 ± 79 Bq kg−1 and for 137Cs was 5 ± 0.5 Bq kg−1. The radiological hazard parameters (representative level index, radium equivalent activity, outdoor and indoor dose rates, outdoor and indoor annual effective dose equivalents, and radiation hazard index) were calculated from the radioactivity in the soil.  相似文献   
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This study was designed to examine stool specimens of irritable bowel syndrome (IBS) patients for Blastocystis hominis, a common intestinal parasite. One hundred fifty patients were enrolled, 95 IBS cases and 55 controls. These patients provided a medical history, and underwent physical and laboratory evaluations that included stool microscopy and culture for B. hominis and colonoscopy. The 95 cases (51 males and 44 females) had a mean +/- SD age of 37.8 +/- 13.2 years. Stool microscopy was positive for B. hominis in 32% (30 of 95) of the cases and 7% (4 of 55) of the controls (P = 0.001). Stool culture was positive in 46% (44 of 95) of the cases and 7% (4 of 55) of the controls (P < 0.001). Stool culture for B. hominis in IBS was more sensitive than microscopy (P < 0.001). Blastocystis hominis was frequently demonstrated in the stool samples of IBS patients; however, its significance in IBS still needs to be investigated. Stool culture has a higher positive yield for B. hominis than stool microscopy.  相似文献   
76.
S ummary Peripheral blood values and bone marrow appearances were monitored in eight patients treated for chronic granulocytic leukaemia in transformation by cytotoxic drugs with or without total body irradiation followed by autografting with cryopreserved-thawed peripheral blood nucleated cells. One of the patients was 'autografted' on two occasions. Five patients had been splenectomized early in the first chronic phase and the other three patients had their spleens intact. Recovery of peripheral blood values was more rapid in the splenectomized than in the non-splenectomized patients. CFUc were present in the circulation immediately after autografting in each case but subsequently the pattern of CFUc changes differed between patients. The bone marrow was hypocellular at the time of autografting but the rate at which it returned to a typical chronic phase picture varied. Peripheral blood nucleated cells collected at the time of diagnosis include stem cells with the capacity to repopulate the marrow after 'ablative' therapy for transformation. Elective splenectomy in the chronic phase may promote more rapid recovery of peripheral blood values but its long-term importance is unknown.  相似文献   
77.
The retinoblastoma tumor suppressor protein pRb restricts cell growth through inhibition of cell cycle progression. Increasing evidence suggests that pRb also promotes differentiation, but the mechanisms are poorly understood, and the key question remains as to how differentiation in tumor cells can be enhanced in order to diminish their aggressive potential. Previously, we identified the histone demethylase KDM5A (lysine [K]-specific demethylase 5A), which demethylates histone H3 on Lys4 (H3K4), as a pRB-interacting protein counteracting pRB''s role in promoting differentiation. Here we show that loss of Kdm5a restores differentiation through increasing mitochondrial respiration. This metabolic effect is both necessary and sufficient to induce the expression of a network of cell type-specific signaling and structural genes. Importantly, the regulatory functions of pRB in the cell cycle and differentiation are distinct because although restoring differentiation requires intact mitochondrial function, it does not necessitate cell cycle exit. Cells lacking Rb1 exhibit defective mitochondria and decreased oxygen consumption. Kdm5a is a direct repressor of metabolic regulatory genes, thus explaining the compensatory role of Kdm5a deletion in restoring mitochondrial function and differentiation. Significantly, activation of mitochondrial function by the mitochondrial biogenesis regulator Pgc-1α (peroxisome proliferator-activated receptor γ-coactivator 1α; also called PPARGC1A) a coactivator of the Kdm5a target genes, is sufficient to override the differentiation block. Overexpression of Pgc-1α, like KDM5A deletion, inhibits cell growth in RB-negative human cancer cell lines. The rescue of differentiation by loss of KDM5A or by activation of mitochondrial biogenesis reveals the switch to oxidative phosphorylation as an essential step in restoring differentiation and a less aggressive cancer phenotype.  相似文献   
78.
The hybrid structure of ZnO NWs with the presence of different dopants recently has drawn many interests from researchers due to the possibility to integrate multiple functionalities into one single structure. In this article, we investigated the morphology, crystal structure and ferromagnetism of the ZnO@Co/Ni hybrid core@shell NWs prepared by a facile electrochemical deposition method. The results show that a thin layer of Ni and Co coated on the surface of ZnO NWs (confirmed by XRD, EDS, TEM and Raman scattering) can create a significant improvement of ferromagnetic property in such hybrid core@shell NWs. In which, for the coating time of 10, 15, 20 min, the value of Ms is around 0.67, 0.88 and 2.56 emu g−1 for ZnO@Co NWs, and about 0.013, 0.022 and 0.031 emu g−1 for ZnO@Ni NWs, respectively, in comparison with the number of 0.016 emu g−1 for pure ZnO NWs. Interestingly, we also found the temperature dependence of ferromagnetism of such Co/Ni coated ZnO NWs. These results reveal the possibility to employ such hybrid core@shell NWs for many applications, e.g. spin field effect transistors.

Facile electrochemical synthesis of ZnO@Co and ZnO@Ni hybrid core@shell nanowires with enhanced ferromagnetism.  相似文献   
79.
We formulated a conceptual framework that begins to answer the national call to improve health care access, delivery, and quality by explaining the processes through which community health workers (CHWs) facilitate patients’ adoption of healthy behaviors. In September 2011 to January 2012, we conducted a qualitative study that triangulated multiple data sources: 26 in-depth interviews, training documents, and patient charts. CHWs served as partners in health to immigrant Filipinos with hypertension, leveraging their cultural congruence with intervention participants, employing interpersonal communication techniques to build trust and rapport, providing social support, and assisting with health behavior change. To drive the field forward, this work can be expanded with framework testing that may influence future CHW training and interventions.Community health workers (CHWs) are laypeople from within the communities where they work, who share common characteristics with their patients (e.g., ethnicity, culture, race, and language).1–4 CHWs have demonstrated effectiveness in an array of conditions, ranging from maternal and child health to chronic disease management.4–12 A systematic review of randomized controlled trials on CHW effectiveness determined that CHWs address health issues among various ethnic and racial groups, help improve use of early intervention services for children at risk for developmental delay, improve screening for breast and cervical cancer, and aid in improving dietary behaviors and blood pressure control.10CHWs have specific training in providing basic nutrition and health promotion services; they aim to improve health care access through a set of core skills,13,14 advocacy, outreach, and education.2,15,16 They function in multiple roles: bridging communication between patients and providers, providing health education and counseling, and monitoring health status.7,12 Thus, CHWs have a tremendous potential to influence and improve health outcomes.Although CHWs play integral roles in supporting patients’ individual health behaviors,17–23 the processes through which they are influential are poorly understood.21 Increasing use of this model in the United States, and recommendations in the Patient Protection and Affordable Care Act to integrate CHWs as part of health care teams,24 underscore the need to advance the knowledge base surrounding CHWs and to better understand mechanisms of this role. We developed a conceptual framework to explicate the processes through which CHWs facilitate the adoption of healthy behaviors among their patients.  相似文献   
80.
We have used intramarrow injection/administration of cytarabine (Ara‐C) instead of conventional intravenous approach to induce remission in an elderly patient with acute myelogenous leukemia. We show for the first time that the intramarrow injection of chemotherapeutic agents such as Ara‐C can be used safely and effectively.  相似文献   
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