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1.
Environmental chemical exposure could be an important etiologic factor for geographic differences in breast cancer incidence. In this study, we examined emissions of polycyclic aromatic hydrocarbons (PAHs) and PM2.5 in relation to breast cancer incidence in metro Atlanta and rural Georgia by analyzing data from the Surveillance, Epidemiology, and End Results Program and the Environmental Protection Agency. The results showed that metro Atlanta had a significantly higher age-adjusted annual incidence rate of female breast cancer than rural Georgia (132.6 vs. 113.7 per 100,000) for 1992–2011. Emissions of both PAHs [adjusted β = 0.568 (95 % CI: 0.209, 0.927); p = 0.004] and PM2.5 [adjusted β = 2.964 (95 % CI: 0.468, 5.459); p = 0.023] were significantly associated with breast cancer incidence in metro Atlanta area. This study suggests that ambient air pollution, especially PAHs and PM2.5, could have a significant impact on the increased incidence of female breast cancer in urban areas.  相似文献   
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BACKGROUND: Many mild-to-moderately obese individuals (body mass index [BMI] 30-35 kg/m(2)) have serious diseases related to their obesity. Nonoperative therapy is ineffective in the long term, yet surgery has never been made widely available to this population. METHODS: Between 1996 and 2004, 93 patients with a BMI of 30-35 kg/m(2) underwent laparoscopic adjustable gastric banding with the LAP-BAND. All patients were referred by their primary physician, entered into a comprehensive bariatric surgery program at one Australian center, and operated on by one surgeon. Data on all patients were collected prospectively and entered into an electronic registry. The study parameters included preoperative age, gender, BMI, presence of co-morbidities, percentage of excess weight loss, and resolution of co-morbidities. RESULTS: The mean age was 44.6 years (range 16-76), mean weight was 98 kg, and the mean BMI was 32.7 kg/m(2) (range 30-34). Of the 93 patients, 42 (45%) had co-morbidities, including asthma, diabetes, hypertension, and sleep apnea. The proportion of patients in follow-up was 79%, 85%, and 89% at 1, 2, and 3 years, respectively. The mean weight was reduced to 71 kg at 1 year, 72 kg at 2 years, and 72 kg at 3 years. The mean BMI was reduced to 27.2 +/- 2.2, 27.3 +/- 3.1, and 27.6 +/- 3.7 kg/m(2), respectively, and the mean percentage of excess weight loss was 57.9% +/- 24.5%, 57.6 +/- 29.3%, and 53.8% +/- 32.8% at 1, 2, and 3 years, respectively. At 3 years, the BMI was 18-24 kg/m(2) in 34%, 25-29 kg/m(2) in 51%, and 30-35 kg/m(2) in 10%. At 3 years, the percentage of excess weight loss was <25% in 10%, 25-50% in 24%, 50-75% in 51%, and >75% in 10%. The co-morbidities improved or completely resolved in most patients. No mortality occurred. CONCLUSION: We are very encouraged by this series of low BMI patients treated with the LAP-BAND. Their weight loss has been good, the complications have been minimal, and the co-morbidities have partially or wholly resolved. With additional study, it is reasonable to expect the weight guidelines for bariatric surgery to be altered to include patients with a BMI of 30-35 kg/m(2).  相似文献   
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BACKGROUND: Abnormalities in calcium and vitamin D metabolism have been reported after bariatric surgery. The purpose of this study was to evaluate vitamin D nutritional status among morbidly obese patients before gastric bypass surgery. METHODS: We prospectively studied 279 morbidly obese patients seeking gastric bypass surgery for vitamin D nutritional status as assessed by serum 25-hydroxyvitamin D level. In addition, serum samples were analyzed for calcium, alkaline phosphatase (AP), intact parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D. RESULTS: Mean patient age was 43 +/- 9 years; 87% of the study patients were women, and 72% were white. Serum calcium and AP levels were normal in 88% and 89% of the patients, respectively. Vitamin D depletion, defined as serum 25-hydroxyvitamin D level 相似文献   
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Blood histamine levels were measured by the bioassay of histamine (on an isolated strip of guinea pig ileum) in workers exposed to cotton dust in a textile mill in Ahmedabad. Byssinotic subjects showed very high levels of blood histamine as compared to nonbyssinotic and control subjects. The blood histamine levels were not well correlated to the dust concentrations or duration of exposure but rather to the day of the week (ie, first, second, third, etc., after weekend break) on which the samples were collected. The blood histamine levels were high on the first day of the work week, when byssinotics complained most of their symptoms.  相似文献   
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BACKGROUND: Various malignancies and cytotoxic chemotherapy have been proposed to increase the risk of reactivation of tuberculosis. Available literature to support this observation is still conflicting. There is scarcity of data from countries with rampant tubercular infection, such as India, in this regard. DESIGN AND METHODS: In the present retrospective analysis, patients with high-grade non-Hodgkin's lymphoma with past history of tuberculosis and have had adequate antitubercular therapy were identified from a Lymphoma Group study. These patients were followed up during cytotoxic chemotherapy and later to assess the risk of reactivation. RESULTS: A cohort of eight patients with past history of tuberculosis was selected from 141 patients of high-grade non-Hodgkin's lymphoma. The median age was 33.5 years (range, 24-53 years). Median duration between completion of antitubercular treatment and diagnosis of lymphoma was 5 years (range, 1.5-10 years). All patients received cyclical cytotoxic chemotherapy. The median duration of follow up after completion of chemotherapy was 5 years (range, 10 months to 5 years). None of these patients developed reactivation of tuberculosis. CONCLUSION: Cyclical chemotherapy for non-Hodgkin's lymphoma does not lead to reactivation of tuberculosis.  相似文献   
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Differential mood changes following basal ganglia vs thalamic lesions   总被引:3,自引:0,他引:3  
Patients with computed tomographic scan-verified unilateral lesions in the basal ganglia or thalamus were examined for the presence of poststroke mood disorders. Patients with left-sided basal ganglia lesions (mainly in the head of the caudate nucleus) showed a significantly higher frequency and severity of depression, as compared with patients with right-sided basal ganglia or thalamic (left- or right-sided) lesions. Results suggest that damage to biogenic amine pathways and/or frontocaudate projections may play an important role in the modulation of mood.  相似文献   
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Thirty-four cases of osteosarcoma involving the craniofacial bones over a period of 19 years were reviewed. They formed 6.2% of osteosarcomas occurring in the skeleton during the same period at the Tata Memorial Hospital. Mean age of occurrence was 30.9% years, with a range of 7 to 61 years. Male preponderance was noted in maxillary tumours (M:F = 2.6:1), while the mandibular tumours occurred with equal frequency in both sexes. The mandible was the bone of origin in 56%, maxilla in 32% and other craniofacial bones in 12% of patients. Histological sub-type did not affect the prognosis. Radical surgery with resection of adequate disease-free margins is the most effective mode of treatment. Morbidity and mortality is due to extensive local recurrence of disease, particularly with maxillary tumours. Metastasis to other organs occurs rarely. No statistically significant difference in survival was observed between tumours of the mandible and maxilla, or between patients above and below 20 years of age.  相似文献   
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Primary salivary gland carcinoma with neuroendocrine differentiation is of rare occurrence, especially so in the parotid gland. Amongst the various reported primary tumors with neuroendocrine differentiation, acinic cell carcinoma (ACC) one such tumor. A 48 year old lady presented with a gradually increasing right infra-auricular swelling for a period of 1 year which enlarged suddenly in a short period. Contrast Enhanced Computed Tomography (CECT) suggested diagnosis of Pleomorphic Adenoma. Fine Needle Aspiration Cytology (FANC) yielded a cystic fluid suggesting a possibility of Warthin’s tumor or Oncocytic lesion. Intraoperative findings were suggestive of a Warthin’s tumor. Initial histopathological examination of the tumor was suggestive of neuroendocrine carcinoma. However, extensive sectioning revealed peripheral islands of ACC. Immunoexpression of S-100, Neuron specific Enolase (NSE), Chromogranin A and Synaptophysin confirmed the diagnosis. The possibility of neuroendocrine differentiation in a primary salivary gland tumor should be kept in mind whenever a salivary gland tumor shows only neuroendocrine histology.  相似文献   
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