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91.
Twenty-eight patients had combined conventional drip infusion CT scans. The information about the anatomic location of the lesion, its configuration, its cross-sectional appearance, its vascularity (as determined by dynamic signature curves), and its clinical presentation were considered as a single overall unit. This diagnostic approach allowed a diagnosis to be made on virtually all of these enhancing lesions without resorting to either a digital venous imaging study or angiographic procedure. In 17 of these cases, such an invasive second procedure was performed either to confirm the CT impression as part of this study or as part of a therapeutic embolization procedure. 相似文献
92.
To determine whether prior oral contraceptive (OC) use is a risk factor for pituitary prolactinoma, we attempted to identify all women (n = 72) with a prolactinoma diagnosed between 1976 and 1980 in three counties in western Washington. A control group of 303 women was selected by dialing random telephone numbers from the same counties. Prior OC use, according to OC indication, was ascertained during a standardized telephone interview. Relative to the risk for women who had never used an OC, the risk of prolactinoma for women who had used OCs for birth control was 1.3 (95% confidence interval, 0.7 to 2.6). This risk was 7.7 for women who used OCs for menstrual regulation (95% confidence interval, 3.7 to 17.0). Previous findings of an association between OC use and prolactinoma may have resulted from OC treatment of menstrual irregularity in women with an undiagnosed prolactinoma. 相似文献
93.
Bronchial artery embolization in the management of hemoptysis: technical aspects and long-term results 总被引:26,自引:0,他引:26
Uflacker R; Kaemmerer A; Picon PD; Rizzon CF; Neves CM; Oliveira ES; Oliveira ME; Azevedo SN; Ossanai R 《Radiology》1985,157(3):637-644
Seventy-five patients with hemoptysis were treated with bronchial artery embolization (BAE). The procedure was performed with Hexabrix (sodium methylglucamine ioxaglate), Mikaelson catheters, and Gelfoam particles. Angiographic evaluation of the bronchial artery anatomy revealed ten different configurations, which are described. The embolization attempt failed in three cases (4%); eight additional patients (10.7%) were excluded from the series because of inadequate data. In the remaining 64 patients, 41 underwent BAE alone and 23 underwent either chemotherapy or surgery in addition to embolization. Immediate control of hemoptysis was achieved in 49 of 64 patients (76.6%). Long-term control of hemoptysis was achieved in 46 of the 56 patients included in the long-term follow-up (82.1%). Eight of the 64 patients were lost to follow-up, which ranged from one to 47 months (mean 24.8 months). Hemoptysis recurred in 12 of 56 patients (severe in 10, mild in 2) (21.4%). Twelve patients died (21.4%), five of them due to hemoptysis (8.9%). None of the patients who died of hemoptysis had responded to initial BAE. It is concluded that BAE is an effective treatment for immediate control of life-threatening hemoptysis, allowing long-term control of bleeding in the majority of patients. 相似文献
94.
Corrine R. Kliment Hagir B. Suliman Jacob M. Tobolewski Crystal M. Reynolds Brian J. Day Xiaodong Zhu Charles F. McTiernan Kenneth R. McGaffin Claude A. Piantadosi Tim D. Oury 《Journal of molecular and cellular cardiology》2009,47(5):730-742
Extracellular superoxide dismutase (EC-SOD) is an antioxidant that protects the heart from ischemia and the lung from inflammation and fibrosis. The role of cardiac EC-SOD under normal conditions and injury remains unclear. Cardiac toxicity, a common side effect of doxorubicin, involves oxidative stress. We hypothesize that EC-SOD is critical for normal cardiac function and protects the heart from oxidant-induced fibrosis and loss of function. C57BL/6 and EC-SOD-null mice were treated with doxorubicin, 15 mg/kg (i.p.). After 15 days, echocardiography was used to assess cardiac function. Left ventricle (LV) tissue was used to assess fibrosis and inflammation by staining, Western blot, and hydroxyproline analysis. At baseline, EC-SOD-null mice have LV wall thinning and increases in LV end diastolic dimensions compared to wild-type mice but have normal cardiac function. After doxorubicin, EC-SOD-null mice have decreases in fractional shortening not apparent in WT mice. Lack of EC-SOD also leads to increases in myocardial apoptosis and significantly more LV fibrosis and inflammatory cell infiltration. Administration of the metalloporphyrin AEOL 10150 abrogates the loss of cardiac function, and potentially fibrosis, associated with doxorubicin treatment in both wild-type and EC-SOD KO mice. EC-SOD is critical for normal cardiac morphology and protects the heart from oxidant-induced fibrosis, apoptosis, and loss of function. The antioxidant metalloporphyrin AEOL 10150 effectively protects cardiac function from doxorubicin-induced oxidative stress in vivo. These findings identify targets for the use of antioxidant agents in oxidant-induced cardiac fibrosis. 相似文献
95.
CF Samer Y Daali M Wagner G Hopfgartner CB Eap MC Rebsamen MF Rossier D Hochstrasser P Dayer JA Desmeules 《British journal of pharmacology》2010,160(4):919-930
Background and purpose:
Thrombus formation is commonly associated with pulmonary arterial hypertension (PAH). Thrombin may thus play an important role in the pathogenesis and pathophysiology of PAH. Hence, we investigated the contractile effects of thrombin and its mechanism in pulmonary artery.Experimental approach:
The cytosolic Ca2+ concentrations ([Ca2+]i), 20 kDa myosin light chain (MLC20) phosphorylation and tension development were evaluated using the isolated porcine pulmonary artery.Key results:
Thrombin induced a sustained contraction in endothelium-denuded strips obtained from different sites of a pulmonary artery, ranging from the main pulmonary artery to the intrapulmonary artery. In the presence of endothelium, thrombin induced a transient relaxation. The contractile effect of thrombin was abolished by either a protease inhibitor or a proteinase-activated receptor 1 (PAR1) antagonist, while it was mimicked by PAR1-activating peptide (PAR1AP), but not PAR4AP. The thrombin-induced contraction was associated with a small elevation of [Ca2+]i and an increase in MLC20 phosphorylation. Thrombin and PAR1AP induced a greater increase in tension for a given [Ca2+]i elevation than that obtained with high K+-depolarization. They also induced a contraction at a fixed Ca2+ concentration in α-toxin-permeabilized preparations.Conclusions and implications:
The present study revealed a unique property of the pulmonary artery. In contrast to normal arteries of the systemic circulation, thrombin induces a sustained contraction in the normal pulmonary artery, by activating PAR1 and thereby increasing the sensitivity of the myofilament to Ca2+. This responsiveness of the pulmonary artery to thrombin may therefore contribute to the pathogenesis and pathophysiology of PAH. 相似文献96.
97.
Hillian AD Londono D Dunn JM Goddard KA Pace RG Knowles MR Drumm ML;CF Gene Modifier Study Group 《Genes and immunity》2008,9(6):501-508
Cystic fibrosis pulmonary disease is characterized by excessive and prolonged inflammation. CF Pulmonary disease severity exhibits considerable variation that, to some extent, appears to be due to the presence of modifier genes. Several components of the inflammatory response are known to have altered regulation in the CF lung. Genetic variants in 52 inflammatory genes were tested for associations with lung disease indices in a CF patient population (n=737) homozygous for the DeltaF508 cystic fibrosis transmembrane conductance regulator mutation. Variants in three inflammatory genes showed significant genotypic associations with CF lung disease severity, including IL8 and previously reported TGFbeta1 (P< or =0.05). When analyzed by gender, it was apparent that IL8 variant associations were predominantly due to males. The IL8 variants were tested in an additional CF population (n=385) and the association in males verified (P< or =0.01). The IL8 variants were in strong linkage disequilibrium with each other (R2> or =0.82), while variants in neighboring genes CXCL6, RASSF6 and PF4V1 did not associate (P> or =0.26) and were in weaker LD with each other and with the IL8 variants (0.01< or =R2< or =0.49). Studies revealed differential expression between the IL8 promoter variant alleles (P<0.001). These results suggest that IL8 variants modify CF lung disease severity and have functional consequences. 相似文献
98.
Kong A Beresford SA Alfano CM Foster-Schubert KE Neuhouser ML Johnson DB Duggan C Wang CY Xiao L Bain CE McTiernan A 《Journal of the American Dietetic Association》2011,111(12):1898-1903
Snacking may play a role in weight control. The associations of timing and frequency of snacking with observed weight change and nutrient intake were assessed in an ancillary study to a 12-month randomized controlled trial in Seattle, WA. Overweight-to-obese postmenopausal women (n=123) enrolled in the two dietary weight-loss arms from 2007 to 2008 with complete data at 12 months were included in these analyses. Generalized linear models were used to test the associations between snacking and weight loss (percent) and nutrient intake at the 12-month time point. Participants were, on average, 58 years old and mainly non-Hispanic white (84%). Ninety-seven percent reported one or more snacks per day. Weight loss (percent) was significantly lower among mid-morning (10:30 am to 11:29 am) snackers (7.0%, 95% confidence interval: 4.3 to 9.7) compared to non–mid-morning snackers (11.4%, 95% confidence interval: 10.2 to 12.6; P=0.005). A higher proportion of mid-morning snackers reported more than one snack per day (95.7%), compared to afternoon (82.8%) and evening (80.6%) snackers, although differences were not statistically significant (P>0.05). Women who reported two or more snacks per day vs one or no snacks per day had higher fiber intake (P=0.027). Afternoon snackers had higher fruit and vegetable intake compared to non–afternoon-snackers (P=0.035). These results suggest that snack meals can be a source for additional fruits, vegetables, and fiber-rich foods; however, snacking patterns might also reflect unhealthy eating habits and impede weight-loss progress. Future dietary weight-loss interventions should evaluate the effects of timing, frequency, and quality of snacks on weight loss. 相似文献
99.