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91.
Postoperative combined modality therapy with radiotherapy and 5-fluorouracil (5FU) chemotherapy is an effective adjuvant approach that reduces locoregional and distant metastatic disease in patients with high-risk rectal carcinoma. However, this approach results in a treatment regimen of at least 6 months’duration. The present prospective study investigates the integration of radiotherapy and 5FU chemotherapy in a protocol designed to minimize toxicity and reduce the overall treatment time. A total of 40 patients with TNM stage II or III disease received postoperative radiotherapy at four fractions per week with weekly 5FU bolus injections delivered on the fifth non-radiotherapy day. Patients also received systemic chemotherapy with leucovorin both before and after pelvic irradiation, with the total treatment duration extending for only 18 weeks. Patients were able to complete radiotherapy in 90% of cases, while the delivery of full-dose chemotherapy was achievable in the vast majority. The incidence of haematologic and gastrointestinal toxicities requiring the cessation of treatment was acceptable. With a median follow-up of 20.9 months among surviving patients, the estimated progression-free and overall survival at 2 years were 71 % and 79%, respectively.  相似文献   
92.
BACKGROUND: Poverty is a major determinant of population health, but little is known about its role in modifying air pollution effects. OBJECTIVES: We set out to examine whether people residing in socially deprived communities are at higher mortality risk from ambient air pollution. METHODS: This study included 209 tertiary planning units (TPUs), the smallest units for town planning in the Special Administrative Region of Hong Kong, China. The socioeconomic status of each TPU was measured by a social deprivation index (SDI) derived from the proportions of the population with a) unemployment, b) monthly household income < US$250, c) no schooling at all, d) one-person household, e) never-married status, and f ) subtenancy, from the 2001 Population Census. TPUs were classified into three levels of SDI: low, middle, and high. We performed time-series analysis with Poisson regression to examine the association between changes in daily concentrations of ambient air pollution and daily number of deaths in each SDI group for the period from January 1996 to December 2002. We evaluated the differences in pollution effects between different SDI groups using a case-only approach with logistic regression. RESULTS: We found significant associations of nitrogen dioxide, sulfur dioxide, particulate matter with aerodynamic diameter < 10 mum, and ozone with all nonaccidental and cardiovascular mortality in areas of middle or high SDI (p < 0.05). Health outcomes, measured as all nonaccidental, cardiovascular, and respiratory mortality, in people residing in high SDI areas were more strongly associated with SO(2) and NO(2) compared with those in middle or low SDI areas. CONCLUSIONS: Neighborhood socioeconomic deprivation increases mortality risks associated with air pollution.  相似文献   
93.
Leung GM  Thach TQ  Chan E  Foo W  Meng O  Fielding R  Lam WW  Hedley AJ  Wong CM  Lam TH 《Cancer》2005,103(3):501-508
BACKGROUND: Estimates of lifetime and shorter-term risks of developing and dying of breast carcinoma are useful translational statistics for risk communication; however, these statistics are unknown for Chinese women, who account for one-fifth of the world's female population. In the current study, the authors examined age-specific 5-year, 10-year, 20-year, and lifetime risks of breast carcinoma incidence and disease-related mortality among Hong Kong women. METHODS: Multiple-decrement life tables were constructed by applying age-specific incidence and mortality rates obtained from cross-sectional data to a hypothetic birth cohort. Incidence, mortality, and population data from 1976 through 2000 were used. RESULTS: For Hong Kong women in the period 1996-2000, the overall lifetime risk of developing invasive breast carcinoma was 5.7% (1 in 17), compared with 10.6% (1 in 9) for U.S. Asian/Pacific Islander women and 14.5% (1 in 7) for U.S. white women. The lifetime breast carcinoma-related mortality risk for Hong Kong women in that same period was 1.7% (1 in 58). For women age 50 years, the 5-, 10-, and 20-year risks of developing breast carcinoma were 0.6% (1 in 172), 1.1% (1 in 87), and 2.1% (1 in 47), respectively. The absolute lifetime probability of developing breast carcinoma increased from 3.81% (1 in 26) during the period 1976-1980 to 5.73% (1 in 17) during the period 1996-2000; 44.5% of this change can be attributed to the increased longevity of women in the latter time period, and the remaining 55.5% can be ascribed to a secular rise in breast carcinoma incidence. CONCLUSIONS: As China becomes more Westernized, the authors expect that the risks of developing and dying of breast carcinoma for Chinese women will become more similar to the corresponding risks for Western women. The current data from Hong Kong, the most Westernized Chinese community, appear to support this conclusion.  相似文献   
94.
Esophageal atresia(EA) is one of the most common congenital digestive malformations and requires surgical correction early in life. Dedicated centers have reported survival rates up to 95%. The most frequent comorbidities after EA repair are dysphagia(72%) and gastroesophageal reflux(GER)(67%). Chronic GER after EA repair might lead to mucosal damage, esophageal stricturing, Barrett's esophagus and eventually esophageal adenocarcinoma. Several long-term follow-up studies found an increased risk of Barrett's esophagus and esophageal carcinoma in EA patients, both at a relatively young age. Given these findings, the recent ESPGHAN-NASPGHAN guideline recommends routine endoscopy in adults born with EA. We report a series of four EA patients who developed a carcinoma of the gastrointestinal tract: three esophageal carcinoma and one colorectal carcinoma in a colonic interposition. These cases emphasize the importance of lifelong screening of the upper gastrointestinal tract in EA patients.  相似文献   
95.
Hepatocellular carcinoma(HCC) is the second most common cause of death from cancer worldwide. Standard potentially curative treatments are either resection or transplantation. The aim of this paper is to provide an overview of the surgical management of HCC, as well as highlight current issues in hepatic resection and transplantation. In summary, due to the relationship between HCC and chronic liver disease, the management of HCC depends both on tumourrelated and hepatic function-related considerations. As such, HCC is currently managed largely through nonsurgical means as the criteria, in relation to the above considerations, for surgical management is still largelyrestrictive. For early stage tumours, both resection and transplantation offer fairly good survival outcomes(5 years overall survival of around 50%). Selection therefore would depend on the level of hepatic function derangement, organ availability and local expertise. Patients with intermediate stage cancers have limited options, with resection being the only potential for cure. Otherwise, locoregional therapy with transarterial chemoembolization or radiofrequency ablation are viable options. Current issues in resection and transplantation are also briefly discussed such as laparoscopic resection, ablation vs resection, anatomical vs non-anatomical resection, transplantation vs resection, living donor liver transplantation and salvage liver transplantation.  相似文献   
96.
Human dirofilariasis caused by infection with Dirofilaria worms has been frequently reported. The symptoms associated with infection by these filarial parasites, which are transmitted to humans by zooanthropophilic mosquitoes, are characterized by mainly pulmonary and subcutaneous nodules. Here, we report the first case in Vietnam of a subcutaneous dirofilariasis with a painful nodule in the right eyelid. An immature female worm was removed by excisional biopsy and identified as Dirofilaria repens by histology and DNA analysis.  相似文献   
97.
PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM.  相似文献   
98.
Since its inception, the field of invasive and interventionalcardiology has witnessed tremendous procedural andtechnological advancements, thereby offering quantumexpansion in clinical applications. As the complexity ofthe subspecialty continues to grow, so does the need forsystematic guidelines and appropriate utilization criteriafor these procedures. To this end, the American Collegeof Cardiology (ACC), in association with the Societyfor Cardiovascular Angiography and Interventions(SCAI) and several other professional societies, hasdeveloped recommended indications for diagnosticcardiac catheterizations and percutaneous coronaryinterventions (PCI) based upon evidence-based literatureor expert concensus. By and large, these guidelines haveemphasized the importance of optimal medical therapy(OMT), regardless of whether an invasive or conservativeapproach is followed. The Appropriate Use Criteria (AUC)aim "to improve patient care and health outcomes in a cost-effective manner while recognizing that some ambiguityand nuance are intrinsic to clinical decision making". 1  相似文献   
99.
100.
Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
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