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61.
Annually, 4.5 trillion cigarette butts (CBs) are flicked into our environment. Evidence exists that CB waste is deadly to aquatic life, but their lethality to the aquatic life of the main dengue vector is unknown. CBs are full of toxicants that occur naturally, during planting and manufacturing, which may act as larvicidal agents. We assessed Aedes aegypti vulnerability to Marlboro butts during its development. Overall, CBs showed insecticidal activities against larvae. At early phases of development, mortality rates were much higher in two CBs solution (2CBSol) and 3CBSol microcosms (MICRs). Larval survival gradually decreased with development in 1CBSol-MICRs. However, in great presence of CBs, mortality was high even for the late developmental stages. These results suggest that A. aegypti larvae are vulnerable to CB presence in their habitats, but this effect was seen most during the early developmental phases and in the presence of increased amounts of cigarette remnants. CB filters are being used as raw material in many sectors, i.e., brick, art, fashion, plastic industries, as a practical solution to the pollution problem, the observed butt waste toxicity to mosquito larvae open new avenues for the identification of novel insecticide products.  相似文献   
62.
Overexpression of the MDM2 Oncogene in Leukemia and Lymphoma   总被引:13,自引:0,他引:13  
A cellular phosphoprotein that binds to and inactivates p53 has recently been identified as a product of the oncogene MDM2. Amplification of the MDM2 gene was found in more than a third of sarcomas and in a subset of malignant gliomas. Despite the absence of amplification, the MDM2 gene was overexpressed in some types of leukemias and lymphomas. Overexpression was significantly more frequent in the low-grade type of B-cell non-Hodgkin's lymphoma (B-NHL) than in the intermediate/high grade types of lymphoma and the overexpression was also significantly more frequent in the advanced rather than the earlier stages of B-cell chronic lymphocytic leukemia (B-CLL) and B-NHL. This suggests that MDM2 could play a role, via the p53 pathway, in tumorigenicity and/or in disease progression in some hematological malignancies. However, in the light of our findings that, in a few cases, both the overexpression of MDM2 and mutant-type p53 was seen, it is possible that MDM2 overexpression may also promote neoplastic growth by mechanisms other than inactivation of the p53 protein.  相似文献   
63.
64.
We used a combination of bone and bone-marrow scintigraphy to study 25 patients with prostatic cancer. Of the 18 cases whose 99mTc-methylene diphosphonate (MDP) bone scans showed hot spots in the lower lumbar region of the spine and/or the pelvic bone, 8 had normal bone-marrow scintigrams. These 8 patients were subsequently shown to have senile, degenerative changes of the spine. On the other hand, in 9 of the 10 patients whose bone-marrow scintigrams showed accumulation defects, follow-up study and characteristic X-ray findings confirmed the presence of metastases. In all 6 cases with extensive bone metastases shown by 99mTc-MDP bone scintigraphy, 99mTc-sulphur-colloid bone-marrow scintigraphy showed multiple accumulation defects. In conclusion, bone-marrow scintigraphy was found to be useful in distinguishing metastatic lesions from benign degenerative changes in the cases with suspected bone involvement, as well as in evaluating equivocal lesions in the pelvis.  相似文献   
65.
66.
Visualization of ocular melanoma with N-isopropyl-p-[123I]-iodoamphetamine   总被引:1,自引:0,他引:1  
In a patient with ocular melanoma, scintigraphy with N-isopropyl-p-[123I]-iodoamphetamine [( 123I]IMP) clearly delineated the histologically proven ocular lesion. In a tissue distribution study, using the resected specimen, a significantly high accumulation of the radioactivity was confirmed in tumor tissue. Thus, [123I]IMP scintigraphy provided specific localization of an ocular melanoma.  相似文献   
67.
Previously, we reported that the deposition of 67Ga into malignant tumors may be a sensitive index of proliferative activity in tumor cells. For the purpose of elucidation of this hypothesis, we investigated the relationship between the accumulation of 67Ga into malignant tumor cells and the intra cellular ATP metabolism in vitro.The uptake of 67Ga into tumor cells was inhibited by adding NaF which is an inhibitor of ATP production. Furthermore, the uptake of 67Ga into tumor cells was strongly inhibited by adding ouabain which is a specific inhibitor of Na+–K+-ATPase. From these in vitro results, it was concluded that there is a correlation between 67Ga uptake and intra cellular ATP metabolism in tumor cells.  相似文献   
68.
Previously we reported that the deposition of 67Ga into malignant tumor may be a sensitive index of proliferative activity in tumor cells. For the purpose of elucidation of this hypothesis, we investigated the relationship between the accumulation of 67Ga into malignant tumor cells and the cell cycle in vitro. We discovered that the uptake of both 67Ga and 59Fe into synchronized mouse tumor cells reaches a peak at the G2 stage which precedes cellular proliferation. Both iron and transferrin are specifically required by cells in culture for cell division, and the fact that 67Ga and 59Fe uptake into tumor cells peaks at the G2 stage of the cell cycle suggests that there is a correlation between 67Ga uptake and the rate of cellular proliferation in malignant tumor cells.  相似文献   
69.
Sone T  Imai Y  Joo YI  Onodera S  Tomomitsu T  Fukunaga M 《BONE》2006,38(5):708-713
The importance of physical activity in the development and maintenance of bone mineral density (BMD) is widely accepted. However, the effects on cortical BMD have not been clarified in detail. The present study examined bilateral asymmetries in cortical BMD of the tibia using peripheral quantitative computed tomography. Subjects comprised 37 young male athletes and 57 controls (age range, 18-28 years). BMD and geometrical indices were determined in bilateral tibiae. Cortical and trabecular BMD were calculated at the diaphysis and distal metaphysis, respectively. Cortical width, periosteal cross-sectional area, and cross-sectional moment of inertia were calculated using tomographic data of the tibial diaphysis. In athletes, the non-dominant leg showed greater cortical BMD than the dominant leg (mean difference, 5.42%; P < 0.0001). Cortical width and moment of inertia were also greater in the non-dominant leg. Periosteal area displayed no significant difference between legs. The control group exhibited similar results except for cortical BMD. No differences in trabecular BMD were noted between legs in either athletes or controls. These results implies the existence of mechanisms for the mechanical adaptation of cortical BMD. Dominant leg is used for mobility or manipulation whereas the non-dominant leg contributes to support the actions of the dominant leg. Loading differences in bilateral legs in young athletes might affect the remodeling rate leading to the side-to-side differences in cortical BMD.  相似文献   
70.
PURPOSE: To investigate the effect of transcorneal electrical stimulation (TES) on the survival of axotomized RGCs and the mechanism underlying the TES-induced neuroprotection in vivo. METHODS: Adult male Wistar rats received TES after optic nerve (ON) transection. Seven days after the ON transection, the density of the surviving RGCs was determined, to evaluate the neuroprotective effect of TES. The levels of the mRNA and protein of insulin-like growth factor (IGF)-1 in the retina after TES were determined by RT-PCR and Northern and Western blot analyses. The localization of IGF-1 protein in the retina was examined by immunohistochemistry. RESULTS: TES after ON transection increased the survival of axotomized RGCs in vivo, and the degree of rescue depended on the strength of the electric charge. RT-PCR and Northern and Western blot analyses revealed a gradual upregulation of intrinsic IGF-1 in the retina after TES. Immunohistochemical analysis showed that IGF-1 immunoreactivity was localized initially in the endfeet of Muller cells and then diffused into the inner retina. CONCLUSIONS: TES can rescue the axotomized RGCs by increasing the level of IGF-1 production by Muller cells. These findings provide a new therapeutic approach to prevent or delay the degeneration of retinal neurons without the administration of exogenous neurotrophic factors.  相似文献   
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