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111.
The present study evaluated the outcome of salvage treatment for women with local or local-regional recurrence after initial breast conservation treatment with radiation for mammographically detected ductal carcinoma in situ (DCIS; intraductal carcinoma) of the breast. The study cohort consisted of 90 women with local only first failure (n=85) or local-regional only first failure (n=5). The histology at the time of recurrence was invasive carcinoma for 53 patients (59%), non-invasive carcinoma for 34 patients (38%), angiosarcoma for one patient (1%), and unknown for two patients (2%). The median follow-up after salvage treatment was 5.5 years (mean=5.8 years; range=0.2-14.2 years). The 10-year rates of overall survival, cause-specific survival, and freedom from distant metastases after salvage treatment were 83%, 95%, and 91%, respectively. Adverse prognostic factors for the development of subsequent distant metastases after salvage treatment were invasive histology of the local recurrence and pathologically positive axillary lymph nodes. These results demonstrate that local and local-regional recurrences can be salvaged with high rates of survival and freedom from distant metastases. Close follow-up after initial breast conservation treatment with radiation is warranted for the early detection of potentially salvageable local and local-regional recurrences.  相似文献   
112.
Reproductive factors are associated with reduced risk of breast cancer, but less is known about whether there is differential protection against subtypes of breast cancer. Assuming reproductive factors act through hormonal mechanisms they should protect predominantly against cancers expressing oestrogen (ER) and progesterone (PR) receptors. We examined the effect of reproductive factors on subgroups of tumours defined by hormone receptor status as well as histology using data from the NIHCD Women's Contraceptive and Reproductive Experiences (CARE) Study, a multicenter case-control study of breast cancer. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) as measures of relative risk using multivariate unconditional logistic regression methods. Multiparity and early age at first birth were associated with reduced relative risk of ER + PR + tumours (P for trend=0.0001 and 0.01, respectively), but not of ER - PR - tumours (P for trend=0.27 and 0.85), whereas duration of breastfeeding was associated with lower relative risk of both receptor-positive (P for trend=0.0002) and receptor-negative tumours (P=0.0004). Our results were consistent across subgroups of women based on age and ethnicity. We found few significant differences by histologic subtype, although the strongest protective effect of multiparity was seen for mixed ductolobular tumours. Our results indicate that parity and age at first birth are associated with reduced risk of receptor-positive tumours only, while lactation is associated with reduced risk of both receptor-positive and -negative tumours. This suggests that parity and lactation act through different mechanisms. This study also suggests that reproductive factors have similar protective effects on breast tumours of lobular and ductal origin.  相似文献   
113.
BACKGROUND: Ductal carcinoma in situ (DCIS) is detected most commonly on routine screening mammography in the asymptomatic patient, and has a long natural history. The objective of the current study was to determine the long-term outcome after breast-conservation surgery followed by definitive breast irradiation for women with mammographically detected DCIS of the breast. METHODS: In total, 1003 women with unilateral, mammographically detected DCIS of the breast underwent breast-conserving surgery followed by definitive breast irradiation. These women were treated in 10 institutions in North America and Europe. The median follow-up was 8.5 years (mean, 9.0 years; range, 0.2-24.6 years). RESULTS: The 15-year overall survival rate was 89%, and the 15-year cause-specific survival rate was 98%. The 15-year rate of freedom from distant metastases was 97%. In total, there were 100 local failures (10%) in the treated breast. The 15-year rate of any local failure was 19%, and the 15-year rate of local only first failure was 16%. Patient age > or = 50 years at the time of treatment and negative final pathology margins from the primary tumor excision both were associated independently with a lower risk of local failure in univariate analysis (P = 0.00062 and P = 0.024, respectively) and in multivariate analysis (P = 0.00057 and P = 0.0026, respectively). For favorable subgroups of patients age > or = 50 years or with negative resection margins, the 10-year risk of local failure was < or = 8%. CONCLUSIONS: The current results support the use of breast-conserving surgery followed by definitive breast irradiation for the treatment of patients with mammographically detected DCIS of the breast. Patient age > or = 50 years at the time of treatment and negative resection margins both were associated independently with a decreased risk of local failure.  相似文献   
114.
OBJECTIVES: We investigated differences in smoking behaviors between US-and Mexican-born ever smokers and examined the influence of US culture on smoking initiation. METHODS: Participants were 5030 adults of Mexican descent enrolled in an ongoing population-based cohort in Houston, Tex. RESULTS: More men than women reported current smoking; rates among US-born women were higher than those among Mexican-born women. Smoking rates among US-born men were higher than earlier published rates among Hispanics and non-Hispanic Whites but similar to rates among African Americans. Current smoking rates among Mexican-born women were lower than published rates for Hispanics, non-Hispanic Whites, and African Americans. Older age, male gender, a higher level of acculturation, more than a high school education, and residing in a census tract with a higher median age predicted history of smoking among US-born participants. Among Mexican-born participants, older age, male gender, a higher level of acculturation, and younger age at migration predicted history of smoking. CONCLUSIONS: Smoking interventions for people of Mexican descent should be tailored according to gender, nativity, and acculturation level and should target all ages, not just young people.  相似文献   
115.
116.
Isolated hepatocyte transplantation for Crigler-Najjar syndrome type 1   总被引:1,自引:0,他引:1  
Crigler-Najjar syndrome type 1 (CN1) is an inherited disorder characterized by the absence of hepatic uridine diphosphoglucuronate glucuronosyltransferase (UDPGT), the enzyme responsible for the conjugation and excretion of bilirubin. We performed allogenic hepatocyte transplantation (AHT) in a child with CN1, aiming to improve bilirubin glucuronidation in this condition. A 9-year-old boy with CN1 was prepared with plasmapheresis and immunosuppression with prednisolone and tacrolimus. When a graft was made available, 7.5 x 10(9) hepatocytes were isolated and infused into the portal vein percutaneously. After 2 weeks phenobarbitone was added to promote the enzymatic activity of UDPGT of the transplanted hepatocytes. Nocturnal phototherapy was continued throughout the studied period. Total bilirubin was considered a reliable marker of allogenic cell function. There was no significant variation of vital signs nor complications during the infusion. Mean +/- SD bilirubin level was 530 +/- 38 micromol/L before and 359 +/- 46 micromol/L after AHT (t-test, p < 0.001). However, the introduction of phenobarbitone was followed by a drop of tacrolimus level with increase of alanine aminotransferase (ALT) and increase of bilirubin. After standard treatment of cellular rejection bilirubin fell again but from then on it was maintained at a greater level. After discharge the patient experienced a further increase of bilirubin that returned to predischarge levels after readmission to the hospital. This was interpreted as poor compliance with phototherapy. Only partial correction of clinical jaundice and the poor tolerability to nocturnal phototherapy led the parents to refuse further hepatocyte infusions and request an orthotopic liver transplant. After 24 months the child is well, with good liver function on tacrolimus and prednisolone-based immunosuppression. Isolated AHT, though effective and safe, is not sufficient to correct CN1. Maintenance of adequate immunosuppression and family compliance are the main factors hampering the success of this procedure.  相似文献   
117.
118.
Multispectral analysis of magnetic resonance images   总被引:1,自引:0,他引:1  
Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.  相似文献   
119.
120.
BACKGROUND: In January 2003, smallpox vaccinations were offered to health care workers to create hospital-based teams prepared to care for patients with smallpox as part of national bioterrorism preparedness activities. METHODS: An anonymous survey of pediatric emergency health care workers was conducted in November and December 2002. Two mailings were sent to physicians, nurses and ancillary staff at five academic pediatric emergency departments in major US cities. We assessed the willingness to receive preevent smallpox vaccine. In addition we measured the prevalence of vaccine contraindications, perceived likelihoods of a local smallpox outbreak or a vaccine-related adverse event and reasons for or against wanting to receive the vaccine. RESULTS: Overall 72% of respondents were willing to receive the smallpox vaccine. Individuals who were willing to receive the smallpox vaccine, compared with those not willing, believed a local outbreak was more likely to occur (odds ratio, 1.29; 95% confidence interval, 1.16 to 1.44). One-fifth of respondents reported a contraindication to smallpox vaccine; however, more than half indicated they would still be willing to receive vaccine. Individuals who perceived themselves at high risk for vaccine-related adverse events were less willing to receive the preevent smallpox vaccine. Self-protection was the most common reason cited for wanting to receive the vaccine. CONCLUSIONS: A majority of pediatric healthcare workers were willing to receive preevent smallpox vaccine before the onset of Phase I of the CDC Smallpox Vaccination Program. A greater understanding of the knowledge, attitudes and beliefs of pediatric health care workers toward preevent smallpox vaccination will assist in the development of future bioterrorism preparedness programs.  相似文献   
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