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1.

This study aimed to examine the side effects of selected neonicotinoids (Acetamiprid, Aceta, and Imidacloprid, Imid) on Oreochromis niloticus juveniles. The acute toxicity, Probit method, revealed an LC50 of 195.81 and 150.76 ppm for Aceta/96 h and Imid/72 h respectively. The fish were divided into three groups that were exposed, for 21 days (n?=?5/replicate), to 1/10 of the LC50 of either neonicotinoids, however, the third was an unexposed control group. Results of erythrocytic micronucleus (MN), and nuclear abnormalities (NA) showed that Aceta and Imid exposure caused a significant (p?<?0.05) increase in MN by?~?2.2 and?~?10 folds, respectively relative to control. NAs occurred at the order of kidney-shaped?>?budding?>?binucleated in Aceta, however, budding?>?binucleated?>?kidney-shaped was noticed in the Imid group. Histopathological changes in gills, liver, and muscles were observed significantly in both exposed groups with more severity in the Imid group. Collectively, Aceta and Imid have potential genotoxicity and histopathological alterations in O. niloticus.

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OBJECTIVE: A wide range of Doppler threshold values for carotid stenosis is found in the literature. We undertook this study to compare methods of derivation and to determine if an optimum strategy of threshold selection exists for a high-risk population. MATERIALS AND METHODS: From the sonograms of all patent internal carotid arteries, peak systolic velocity in the internal carotid artery (ICA(PSV)) and the ratio of peak systolic velocity in the internal carotid artery to that of the common carotid artery (ICA(PSV)/ CCA(PSV)) were compared with the percentage of angiographically determined stenosis. Receiver operating characteristic curves were generated for levels of stenosis > or =60% and > or =70%. Doppler thresholds were chosen on the basis of maximum accuracy and on the basis of > or =90% sensitivity and specificity. Patients were then segregated into symptomatic and asymptomatic cohorts, and the above process was repeated. An effectiveness analysis was also conducted using various Doppler thresholds. Thresholds derived using these three methods were compared and optimal values chosen. RESULTS. Of 333 carotid arteries that fit inclusion criteria, 132 were found in asymptomatic patients and 201 in symptomatic patients. Maximum accuracy, > or =90% sensitivity and specificity, and effectiveness analysis each produced different ranges of thresholds. We chose final thresholds that maintained patient outcome profiles. For asymptomatic patients at the > or =60% stenosis level, thresholds were ICA(PSV) = 200 cm/sec and ICA(PSV)/CCA(PSV) = 3.0. For symptomatic patients with stenosis > or =70%, thresholds were ICA(PSV) = 175 cm/sec and ICA(PSV)/CCA(PSV) = 2.5. CONCLUSION: Considerable latitude exists in the choice of carotid Doppler thresholds. We propose a rational strategy for threshold selection based on a combination of three commonly used methods. Our observations indicate that it appears advisable to consider symptomatic and asymptomatic patients separately and to apply appropriately derived thresholds.  相似文献   
3.
PURPOSE: To determine if duplex ultrasonography (US) can help predict the degree of internal carotid arterial (ICA) stenosis. MATERIALS AND METHODS: ICA peak systolic velocity (PSV) and the ratio of the PSV in the ICA to that in the ipsilateral common carotid artery (VICA/VCCA) were compared with the degree of arteriographically measured stenosis. ICAs were arteriographically subgrouped at 10% incremental levels of stenosis and broader ranges. Mean PSV, VICA/VCCA, and SDs were calculated for each category. Histograms showing the numbers of stenotic ICAs in subgroups and for vessels with stenoses of greater than or equal to or less than 70% narrowing were constructed. The number of vessels correctly subgrouped with typical Doppler US thresholds was calculated. RESULTS: Mean PSV and VICA/VCCA increased with stenosis level (P < .01); SDs were wide. Histograms showed Doppler US values in the central groups across all disease levels. Histograms differentiating at least or less than 70% stenosis showed minimal overlap. PSV and VICA/VCCA helped classify, respectively, 185 and 181 of 204 vessels with stenoses of less than 50%, 15 and 21 of 46 vessels with stenoses of 50%-69%, and 73 and 67 of 84 vessels with stenoses of 70% or greater. When classifying stenoses as 69% or less or 70% or more, PSV and VICA/VCCA were correct in 90.6% and 90.3% of vessels. CONCLUSION: Doppler US is excellent for classifying stenoses as above or below a single degree of severity but does not function well in stenosis subclassification.  相似文献   
4.
Summary: A case of primary carcinoma of the left Fallopian tube is reported. The patient presented with postmenopausal bleeding which persisted after curet-tage and removal of a benign endometrial polyp. Total hysterectomy and bilateral salpingo-oophorectomy was performed, and the diagnosis of tubal carcinoma was made only on histopathological examination of the specimen.  相似文献   
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6.
Trimethoprim-sulphamethoxazole in acute brucellosis   总被引:2,自引:0,他引:2  
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The adriamycin resistant breast cancer cell line (MCF-7/ADR) is a subject of ongoing debate concerning its origin and or source. Previous studies in our laboratory showed that MCF-7/ADR has a unique cytosolic protein expression pattern when compared to that of the parental MCF-7 cell line and other drug resistant MCF-7 cell lines. Protein expression patterns obtained using two-dimensional gel electrophoresis and mass spectrometry indicated that this MCF-7/ADR cell line shares some similarities with the metastatic breast cancer cell lines MDA-MB. Further comparisons with available two-dimensional gel electrophoresis maps in the literature indicate that MCF-7/ADR has a protein expression signature even closer to of the ductal infiltrating breast carcinoma cell line 8701. These observations suggest that MCF-7/ADR cells might have originated in a selection of ductal infiltrating carcinoma cells, which were present among the original MCF-7 cell population. These ductal infiltrating carcinoma cells may possess an intrinsic adriamycin resistance phenotype.  相似文献   
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10.
Abstract: Objective: To assess the role of ambient air pollutants in type 1 diabetes in children. Design and methods: Prediagnosis exposure to five air pollutants was studied in two subgroups with onset of type 1 diabetes before and after 5 yr of age, and two matched subgroups of healthy children. Zip codes and dates of residence from birth to diagnosis were used to obtain geographic‐ and time‐specific air concentrations of SO2, NO2, ozone (O3), SO4, and particulate matter < 10 µm in diameter (PM10). Prediagnosis time‐adjusted pollutant exposure levels were created by summing up zip code‐specific pollution data and dividing by months of exposure from birth to diagnosis. Two‐tailed t‐test and logistic regression were used to evaluate relative effects and test data between cases and controls. Results: Prediagnosis average O3 exposure was significantly higher in children with type 1 diabetes than in healthy controls. Prediagnosis PM10 exposure was significantly higher in children diagnosed before 5 yr of age, when compared with healthy controls. SO2 exposure was significantly higher in children with later‐onset diabetes compared with those with early‐onset diabetes (EOD). NO2, SO2 and SO4 exposure was significantly lower in children diagnosed after 5 yr of age, when compared with healthy controls. O3, NO2, SO4 and PM10 levels did not significantly differ between the two diabetic subgroups. Conclusion: Increased ozone exposure may be a contributory factor to the increased incidence of type 1 diabetes. PM10 may be a specific contributory factor to the development of type 1 diabetes before 5 yr of age.  相似文献   
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