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201.
We report the case of a patient with advanced squamous carcinoma of the supraglottic larynx and hypopharynx who developed metastatic gastric deposits occurring at the site of a percutaneous endoscopic gastrostomy tube, inserted 10 months previously by the pull technique. We review seven previous reports of tumour deposits occurring at the site of placement of a percutaneous endoscopic gastrostomy in patients with head and neck cancer, and consider alternative methods of enteral feeding in such patients. 相似文献
202.
This evaluation of the third year of the Massachusetts Medicaid managed Mental Health/Substance Abuse Program showed that overall utilization increased slightly and expenditures were nearly the same in FY1994 compared to FY1993; however, they were lower for disabled members. Providers believed that access to care, utilization, and quality of care were the same or better than a year earlier and that the clinical review process was improved. Client severity was higher. Aftercare planning improved but gaps in services persisted. Integration of care improved. Administrative and management problems continued. Lessons for similar, more recent initiatives are discussed. 相似文献
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The adsorption and degradation behavior of RDX, HMX, TNT and DNT and the impact of pH, ionic strength and dissolved organic matter on sorption were examined for two volcanic soils of a former military training area on Hawaii Island, Hawaii, USA. The transport of these chemicals in the soil was also studied in small packed columns and simulated using a water-flow and solute-transport model, HYDRUS_1D. The results show that HMX and RDX are both significantly more mobile than TNT and DNT. The adsorbability of the four chemicals was ranked as: RDXRDX>DNT>TNT. No significant trend was observed for the effect of ionic strength, pH and dissolved organic carbon (DOC) on the adsorption of explosive compounds within the concentrations and pH ranges evaluated. The simulation results show that TNT and DNT would not leach beyond a depth of 30cm soil profile whereas a significant amount of HMX and RDX would pass the 30cm depth. It seems that the risk for contamination of groundwater is much higher for both HMX and RDX than for DNT and TNT as the substratum in this area consists of highly permeable lavas. 相似文献
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LE Taylor DS Kronfeld PL Ferrante JA Wilson W Tiegs 《Canadian Metallurgical Quarterly》1998,85(3):1030-1036
Rectal temperature (Tre) is often used to adjust measurements of blood gases, but these adjusted measurements may not approximate temperatures during intense exercise at main sites of gas exchange: muscle and lung. To evaluate differences in blood gases between sites, temperatures (T) were measured with thermocouples in the rectum (re), in mixed venous blood (v), in gluteal muscle (mu), and on the skin (sk) in seven Arabian horses as they underwent an incremental exercise test on a treadmill. Blood samples were drawn from the carotid artery and pulmonary artery (mixed venous) 30 s before each increase in speed and during recovery. Blood gases and pH were measured at 37 degreesC, and all variables were adjusted to Tre, Tv, and Tmu. Adjusted variables during exercise and recovery were significantly different from each other at the three sites. Linear and polynomial equations described the time course of venous temperature and from Tre and Tsk during exercise and from Tsk during recovery. Interpretation of changes in muscle metabolism and gas exchanges based on blood-gas measurements is improved if they are adjusted appropriately to Tmu or Tv, which may be predicted from Tsk in addition to Tre during strenuous exercise and from Tsk during recovery. 相似文献
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SM Schwartz DB Petitti DS Siscovick WT Longstreth S Sidney TE Raghunathan CP Quesenberry J Kelaghan 《Canadian Metallurgical Quarterly》1998,29(11):2277-2284
BACKGROUND AND PURPOSE: The available data on low-dose oral contraceptive pill (OCP) use and stroke risk in US women are limited by small numbers. We sought more precise estimates by conducting a pooled analysis of data from 2 US population-based case-control studies. METHODS: We analyzed interview data from 175 ischemic stroke cases, 198 hemorrhagic stroke cases, and 1191 control subjects 18 to 44 years of age. RESULTS: For ischemic stroke, the pooled odds ratio (pOR) adjusted for stroke risk factors for current use of low-dose OCPs compared with women who had never used OCP (never users) was 0.66 (95% confidence interval [CI], 0.29 to 1.47) and compared with women not currently using OCPs (nonusers) the pOR was 1.09 (95% CI, 0.54 to 2.21). For hemorrhagic stroke, the pOR for current use of low-dose OCPs compared with never users was 0.95 (95% CI, 0.46 to 1.93) and compared with nonusers the pOR was 1.11 (95% CI, 0.61 to 2.01). The pORs for current low-dose OCP use and either stroke type were not elevated among women who were >/=35 years, cigarette smokers, obese, or not receiving medical therapy for hypertension. pORs for current low-dose OCP use were 2.08 (95% CI, 1. 19 to 3.65) for ischemic stroke and 2.15 (95% CI, 0.85 to 5.45) for hemorrhagic stroke among women reporting a history of migraine but were not elevated among women without such a history. Past OCP use (irrespective of formulation) was inversely related to ischemic stroke but unrelated to hemorrhagic stroke. CONCLUSIONS: Women who use low-dose OCPs are, in the aggregate, not at increased risk of stroke. Studies are needed to clarify the risk of stroke among users who may be susceptible on the basis of age, smoking, obesity, hypertension, or migraine history. 相似文献
210.
BF O'Donnell JR Marsden CA O'Donnell DS Sanders C Billingham 《Canadian Metallurgical Quarterly》1996,34(4):632-637
BACKGROUND: Relatively few studies have addressed the question of whether clinical estimation of melanoma thickness by palpation can accurately predict its histologic thickness. If palpability was a reliable predictor of dermal invasion, it could be used to define the surgical margin. OBJECTIVE: We sought to determine whether clinical elevation of melanoma could be used to predict the presence or absence and the degree of dermal invasion in patients with stage 1 cutaneous melanoma. METHODS: Melanomas in 165 patients were categorized by one observer as flat, just palpable, palpable, or nodular. This was compared with histologic measurements of tumor thickness. RESULTS: Overall there was significant correlation between the degree of palpability of melanoma and the presence or absence of dermal invasion (p<0.001), Breslow thickness (p<0.0001), and Clark level (p<0.001). However, the relation between palpability and Breslow thickness for invasive melanomas less than 1 mm thick was weaker (n=62, p=0.053), and the correlation between elevation and Clark level was not significant for invasive melanomas less than 4 mm thick (n=111, p>0.999). CONCLUSION: We conclude that palpability of melanoma is an inadequate guide to the presence or absence and degree of dermal invasion in melanomas less than 1 mm thick and cannot be used to determine the surgical margin. 相似文献