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151.
Neuroendocrine carcinoma of the larynx is a rare entity constituting about 0.6% of all laryngeal malignancies. An interesting case of neuroendocrine carcinoma of supraglottis in a 70 year old lady is being reported  相似文献   
152.
Although exposure to moderate-to-high doses of ionizing radiation is the only established environmental risk factor for brain and CNS tumors, it is not clear whether this relationship differs across tumor subtypes, by sex or age at exposure, or at the low-to-moderate range of exposure. This systematic review summarizes the epidemiologic evidence on the association between ionizing radiation exposure and risk of brain/CNS tumors. Articles included in this review estimated radiation exposure doses to the brain and reported excess relative risk (ERR) estimates for brain/CNS tumors. Eight cohorts were eligible for inclusion in the analysis. Average age at exposure ranged from 8 months to 26 years. Mean dose to the brain ranged from 0.07 to 10 Gy. Elevated risks for brain/CNS tumors were consistently observed in relation to ionizing radiation exposure, but the strength of this association varied across cohorts. Generally, ionizing radiation was more strongly associated with risk for meningioma compared with glioma. The positive association between ionizing radiation exposure and risk for glioma was stronger for younger vs older ages at exposure. We did not observe an effect modification on the risk for meningioma by sex, age at exposure, time since exposure, or attained age. The etiologic role of ionizing radiation in the development of brain/CNS tumors needs to be clarified further through additional studies that quantify the association between ionizing radiation and risk for brain/CNS tumors at low-to-moderate doses, examine risks across tumor subtypes, and account for potential effect modifiers.  相似文献   
153.
The 600% increase in medical radiation exposure to the US population since 1980 has provided immense benefit, but increased potential future cancer risks to patients. Most of the increase is from diagnostic radiologic procedures. The objectives of this review are to summarize epidemiologic data on cancer risks associated with diagnostic procedures, describe how exposures from recent diagnostic procedures relate to radiation levels linked with cancer occurrence, and propose a framework of strategies to reduce radiation from diagnostic imaging in patients. We briefly review radiation dose definitions, mechanisms of radiation carcinogenesis, key epidemiologic studies of medical and other radiation sources and cancer risks, and dose trends from diagnostic procedures. We describe cancer risks from experimental studies, future projected risks from current imaging procedures, and the potential for higher risks in genetically susceptible populations. To reduce future projected cancers from diagnostic procedures, we advocate the widespread use of evidence‐based appropriateness criteria for decisions about imaging procedures; oversight of equipment to deliver reliably the minimum radiation required to attain clinical objectives; development of electronic lifetime records of imaging procedures for patients and their physicians; and commitment by medical training programs, professional societies, and radiation protection organizations to educate all stakeholders in reducing radiation from diagnostic procedures. CA Cancer J Clin 2012. © 2012 American Cancer Society.  相似文献   
154.
Health promotion is very relevant today. There is a global acceptance that health and social wellbeing are determined by many factors outside the health system which include socioeconomic conditions, patterns of consumption associated with food and communication, demographic patterns, learning environments, family patterns, the cultural and social fabric of societies; sociopolitical and economic changes, including commercialization and trade and global environmental change. In such a situation, health issues can be effectively addressed by adopting a holistic approach by empowering individuals and communities to take action for their health, fostering leadership for public health, promoting intersectoral action to build healthy public policies in all sectors and creating sustainable health systems. Although, not a new concept, health promotion received an impetus following Alma Ata declaration. Recently it has evolved through a series of international conferences, with the first conference in Canada producing the famous Ottawa charter. Efforts at promoting health encompassing actions at individual and community levels, health system strengthening and multi sectoral partnership can be directed at specific health conditions. It should also include settings-based approach to promote health in specific settings such as schools, hospitals, workplaces, residential areas etc. Health promotion needs to be built into all the policies and if utilized efficiently will lead to positive health outcomes.  相似文献   
155.
Urovysion fluorescence in situ hybridization (UVFISH) identifies malignant cells in urine by detecting specific urothelial carcinoma-related chromosomal abnormalities. Some renal carcinomas (RCCs) share overlapping chromosomal aberrations with urothelial carcinoma. Malignant renal cells that are shed in urine can potentially cause a positive UVFISH result. We evaluated UVFISH in RCCs to determine its potential applicability to the diagnosis and grading of RCCs. Paraffin blocks from 39 RCCs (25 clear cell, 9 papillary, 2 chromophobe, and 3 sarcomatoid) and 15 controls (5 renal oncocytomas and 10 urothelial carcinomas) were tested. Of the RCCs, 15 (40%) were UVFISH-positive (9/25 [40%] clear cell, 3/9 [30%] papillary, 1/2 [50%] chromophobe, and 2/3 [67%] sarcomatoid carcinoma) and 24 (60%) were negative. Of the 15 controls, 8 (~50%) were UVFISH-positive (2/5 [40%] oncocytomas and 6/10 [60%] urothelial carcinomas) and 7 (~50%) were UVFISH-negative. Polysomy of chromosome 17 showed a statistically significant correlation with RCC subtype, being absent in most of the clear cell RCCs (P = .0096) compared with other RCCs. Polysomy of chromosome 7 was more frequent in high-grade than low-grade RCC (P = .0197) and more likely in high-grade clear cell than low-grade clear cell RCC (P = .0120). In conclusion, we showed that RCC has overlapping chromosomal abnormalities with urothelial carcinoma and can cause a positive UVFISH result. This has implications for the interpretation of Urovysion in patients whose urine contains malignant cells but who have negative cystoscopy and a concomitant renal mass. The chromosomal abnormalities observed in RCC are not distinct from those in urothelial carcinoma; therefore, UVFISH cannot distinguish these tumor types, nor can it type or grade RCC.  相似文献   
156.

Purpose

To assess risk of developing a second benign brain tumor in a nationwide population of cancer survivors.

Methods

We evaluated the risk of developing second benign brain tumors among 2,038,074 1-year minimum cancer survivors compared to expected risk in the general population between 1973 and 2007 in nine population-based cancer registries in the NCI’s surveillance, epidemiology, and end results program. Excess risk was estimated using standardized incidence ratios (SIRs) for all second benign brain tumors and specifically for second meningiomas and acoustic neuromas diagnosed during 2004–2008.

Results

1,025 patients were diagnosed with a second primary benign brain tumor, of which second meningiomas composed the majority (n = 745). Statistically significant increases in risk of developing a second meningioma compared to the general population were observed following first cancers of the brain [SIR = 19.82; 95 % confidence interval (CI) 13.88–27.44], other central nervous system (CNS) (SIR = 9.54; CI 3.10–22.27), thyroid (SIR = 2.05; CI 1.47–2.79), prostate (SIR = 1.21; CI 1.02–1.43), and acute lymphocytic leukemia (ALL) (SIR = 42.4; CI 23.18–71.13). Statistically significant decreases in risk were observed following first cancers of the uterine corpus (SIR = 0.63; CI 0.42–0.91) and colon (SIR = 0.56; CI 0.37–0.82). Differences in risk between patients initially treated with radiotherapy versus non-irradiated patients were statistically significant for second meningioma after primary cancers of the brain (p Het < 0.001) and ALL (p Het = 0.02). No statistically significant increased risks were detected for second acoustic neuromas (n = 114) following any first primary tumor.

Conclusions

Risk of second benign brain tumors, particularly meningioma, is increased following first primary cancers of the brain/CNS, thyroid, prostate, and ALL. Radiation exposure likely contributes to these excess risks.  相似文献   
157.
Neuroendocrine carcinoma of the larynx is a rare entity constituting about 0.6% of all laryngeal malignancies. An interesting case of neuroendocrine carcinoma of supraglottis in a 70 year old lady is being reported  相似文献   
158.
Titin/connectin is the main determinant of physiological levels of passive muscle force. This force is generated by the extensible I-band region of the molecule, which is composed of serially-linked immunoglobulin (Ig)-like domains and several unique sequence elements. Here we address the role of titin/connectin in sarcomeres shortened to below the slack length (length attained by an un-activated cell in absence of external forces). Such shortened cells develop so-called restoring forces that re-extend the cells upon relaxation. The experiments that we present are based on a high throughput method with a rapid solution switching system which allows unattached single cardiac myocytes to be activated (resulting in shortening below the slack length) and then to be rapidly relaxed while their maximal re-lengthening velocity is measured at the sarcomere level (dSL/dt max), with high-resolution imaging techniques. Experiments were carried out on myocytes that express different isoforms of titin/connectin. We measured the relation between dSL/dt max and the minimal SL during contraction (SLmin) and determined the slope of this relation as a measure of ‘restoring stiffness.’ We found that the restoring stiffness correlates with the isoform expression profile with myocytes that express high levels of the stiff isoform (N2B) having the highest restoring stiffness. These results support the notion that titin/connectin is a bi-directional spring that develops passive force when stretched above the slack length and restoring force when shortened to below this length. We also discuss in detail the mechanisms that underlie titin/connectin’s restoring force development and focus on whether or not unfolding of Ig domains plays a role.  相似文献   
159.
160.
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