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121.
C Joseph Muniz Arthur C Fleischer Edwin F Donnelly Murray J Mazer 《Journal of ultrasound in medicine》2002,21(2):129-133
OBJECTIVE: To assess the accuracy of three-dimensional color Doppler sonography and uterine artery arteriography in depicting changes in fibroid vascularity before and after embolization. METHODS: Preembolization and postembolization three-dimensional color Doppler sonography and selective uterine artery arteriography were retrospectively compared in 15 patients who underwent uterine artery embolization for treatment of symptomatic fibroids. Three-dimensional color Doppler sonography was performed by using a scanner with color power angiographic imaging capability. Vascularity was quantified by using an estimation of power-weighted pixel density as described by our group in previously published studies. Uterine artery arteriography was performed by using a standard selective microcatheter embolization technique. For purposes of comparison, fibroids were classified as either hypervascular or hypovascular relative to myometrial vascularity before and minutes to several hours after uterine artery embolization. Changes in fibroid vascularity (i.e., from hypervascular to hypovascular) as depicted by three-dimensional color Doppler sonography were compared with those shown on uterine artery arteriography and classified as being in agreement or disagreement. RESULTS: In 13 (87%) of 15 patients there was agreement; in 2 (13%) of 15 there was disagreement. In both cases of disagreement, three-dimensional color Doppler sonography showed collateral flow not depicted by uterine artery arteriography The mean reduction in quantitated vascularity after uterine artery embolization was 44% (range, 19%-78%). CONCLUSIONS: Three-dimensional color Doppler sonography accurately depicts fibroid vascularity and in some cases can reveal collateral flow not depicted by uterine artery arteriography. 相似文献
122.
L Joseph Melton 《Journal of bone and mineral research》2003,18(6):1139-1141
Osteoporotic fractures exact a terrible toll on the population with respect to morbidity and cost, and to a lesser extent mortality, which will increase dramatically with the growing elderly population. Attention has focused on the 12-20% excess deaths after hip fracture, but most are caused by underlying medical conditions unrelated to osteoporosis. More important is fracture-related morbidity. An estimated 10% of patients are disabled by hip fracture, and 19% require institutionalization, accounting for almost 140,000 nursing home admissions annually in this country. Distal forearm and vertebral fractures less commonly result in nursing home placement, but about 10% of postmenopausal women have vertebral deformities that cause chronic pain, and a substantial minority have poor function after forearm fracture. These fractures interfere greatly with the activities of daily living, and all of them can have a substantial negative impact on quality of life. Annual expenditures for osteoporotic fracture care in the United States (dollar 17.5 million in 2002 dollars) are dominated by hip fracture treatment, but vertebral fractures, distal forearm fractures, and importantly, the other fractures related to osteoporosis contribute one-third of the total. Although all fracture patients are at increased risk of future fractures, few of them are currently treated for osteoporosis, and only a subset (i.e., those with vertebral fractures) are considered candidates for many clinical trials. Eligibility criteria should be expanded and fracture end-points generalized to acknowledge the overall burden of osteoporotic fractures. 相似文献
123.
Impaired cortisol stress response in fish from environments polluted by PAHs,PCBs, and mercury 总被引:6,自引:0,他引:6
Alice Hontela Joseph B. Rasmussen Céline Audet Gaston Chevalier 《Archives of environmental contamination and toxicology》1992,22(3):278-283
The cortisol stress response to capture was investigated in two species of fish (Perca flavescens and Esox lucius) from sites polluted by high levels of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and mercury, and from reference sites in the St. Lawrence river system. Fish from the reference sites exhibited the normal elevation of serum cortisol in response to the acute stress of capture and had large pituitary corticotropes. In contrast, fish from the most polluted sites were unable to increase their serum cortisol in response to the acute stress of capture and their pituitary corticotropes were atrophied. These results suggest that a life-long exposure to chemical pollutants may lead to an exhaustion of the cortisol-producing endocrine system, possibly as a result of prolonged hyperactivity of the system. 相似文献
124.
Joseph V. Hajnal Ralph Myers Angela Oatridge Jane E. Schwieso Ian R. Young Graeme M. Bydder 《Magnetic resonance in medicine》1994,31(3):283-291
To assess the effect of stimulus correlated motion on the appearance of functional magnetic resonance images, conventional visual and motor protocols were each performed by four normal volunteers and an image co-registration technique was used to retrospectively monitor subject motion. In three studies synthetic data sets were constructed from single baseline images using the positional information obtained from the co-registration procedure. Cumulative difference images were then created from both the synthetic and functional image sets. Stimulus correlated motion was detected in all eight studies and the synthetic cumulative difference images showed striking similarities to the equivalent functional images in each case. 相似文献
125.
Esther Kahana Nelly Zilber Joseph H. Abramson Victor Biton Yaffa Leibowitz Oded Abramsky 《Journal of neurology》1994,241(5):341-346
The incidence and prevalence of multiple sclerosis (MS) were compared, controlling for age, in native-born Israelis of different origins and in immigrants to Israel. This comparison was carried out in two populations, countrywide and in Jerusalem. In the countrywide population, ascertainment was based mainly on hospitalizations; it included 252 patients who were native-born and 150 who had immigrated from Africa-Asia (AA immigrants). The 89 MS patients of Jerusalem also included patients diagnosed in outpatient clinics. In native-born Israelis whose father was born in Europe-America (I-EA), the incidence and prevalence of MS were found to be as high as or even higher than that found previously in immigrants from Europe-America. Among native-born Israelis whose father was born in Africa or Asia (I-AA), the yearly age-adjusted incidence and prevalence rates were found to be 1.4- to 1.8-fold higher than among AA immigrants, pointing to environmental factors. The incidence and prevalence rates in the I-EA were 1.2- to 1.6-fold higher than in the I-AA, pointing to genetic factors. These results seem to point to both environmental and genetic factors in the aetiology of MS. Further research is needed, however, to disentangle the genetic factors from possible environmental differences in the two ethnic groups. 相似文献
126.
European system for cardiac operative risk evaluation predicts long-term survival in patients with coronary artery bypass grafting. 总被引:3,自引:0,他引:3
Ioannis K Toumpoulis Constantine E Anagnostopoulos Joseph J DeRose Daniel G Swistel 《European journal of cardio-thoracic surgery》2004,25(1):51-58
OBJECTIVE: To evaluate the accuracy of predicting long-term mortality in patients with coronary artery bypass grafting (CABG) by using the European system for cardiac operative risk evaluation (EuroSCORE). METHODS: Medical records of patients with CABG (n=3760) between January 1992 and March 2002 were retrospectively reviewed and their predicted surgical risk was calculated according to the standard (study A) and logistic (study B) EuroSCORE. In study A the patients were divided into six groups: 0-2 (n=610), 3-5 (n=1479), 6-8 (n=1099), 9-11 (n=452), 12-14 (n=103) and >14 (n=17). In study B the patients were divided into seven groups: 0.00-2.00 (n=447), 2.01-5.00 (n=1190), 5.01-10.00 (n=890), 10.01-20.00 (n=686), 20.01-30.00 (n=234), 30.01-60.00 (n=254) and >60.00 (n=59). Long-term survival was obtained by the National Death Index and Kaplan-Meier curves were constructed and compared employing the log-rank test. Multivariate Cox regression analysis was performed in order to control for pre, intra and postoperative factors and adjusted hazard ratios were calculated for standard and logistic EuroSCORE groups. The receiver operating characteristic (ROC) curves were plotted to assess the discrimination ability of the EuroSCORE. RESULTS: In study A there were differences among the six groups in 30-day mortality (0.7%, 1.0%, 3.1%, 4.6%, 13.6% and 23.5%; P<0.001), in major complications (8.5%, 10.4%, 16.2%, 20.4%, 31.1% and 35.3%; P<0.001) as well as in actuarial long-term survival (86.2%, 79.6%, 53.6%, 37.9%, 24.9% and 0% from EuroSCORE 0-2 to >14; P<0.001). In study B there were differences among the seven groups in 30-day mortality (0.9%, 1.1%, 1.2%, 3.6%, 3.4%, 8.7% and 15.3%; P<0.001), major complications (8.5%, 10.1%, 12.1%, 18.4%, 16.2%, 26.0% and 30.5%; P<0.001) as well as in actuarial long-term survival (89.5%, 79.9%, 66.9%, 51.0%, 40.3%, 38.4% and 13.7% from EuroSCORE 0.00-2.00 to >60.00; P<0.001). Multivariate Cox regression analysis confirmed that EuroSCORE (standard or logistic) was a statistically significant predictor for long-term mortality, while the area under the ROC curve was 0.72 for either standard or logistic EuroSCORE. CONCLUSION: The predicted surgical risk in CABG patients as calculated by standard or logistic EuroSCORE is a strong predictor for long-term survival in addition to predicting operative survival for which it was originally designed. 相似文献
127.
G P Tuszynski M Smith V L Rothman D M Capuzzi R R Joseph J Katz E C Besa J Treat H I Switalska 《Thrombosis and haemostasis》1992,67(6):607-611
Thrombospondin (TSP), a large glycoprotein present in platelets, and various normal and tumor tissues, has recently been shown to promote cell adhesion and platelet aggregation. Most importantly because TSP has been shown to promote metastasis of melanoma tumor cells to the lung in a murine model (1) and since thromboembolic events commonly occur in patients afflicted with metastatic tumors, we explored the role of TSP in human cancer by measuring TSP blood levels in patients with various malignant neoplasms. Blood TSP levels were measured by indirect enzyme-linked immunoadsorbent assay (ELISA) from 20 control subjects, 22 patients with gastrointestinal (GI) cancer, 18 patients with breast cancer, and 17 patients with lung cancer. Control subjects consisted both of healthy subjects and acutely ill patients with no malignancies. TSP levels of both healthy and acutely ill controls were found to range between 245-440 ng/ml with a mean of 365 ng/ml. In contrast, elevated levels of TSP greater than the mean value of 400 ng/ml for controls ranging between 590-3,650 ng/ml were found in 20/22 (91%) patients with GI malignancies, 13/18 (72%) patients with breast cancer, and 15/17 (88%) with lung cancer. Mean TSP levels of GI, breast, and lung cancer patients were 3, 2, and 3 fold greater than controls, respectively. Increased blood TSP levels in patients were not due to increased levels of platelets since both control and patient groups had platelet counts within the normal range. These results suggest that TSP may play a role in tumor cell metastasis in man and could serve as a blood marker for metastasis. 相似文献
128.
129.
130.
Trang T. Duong Joanne St. Louis Joseph J. Gilbert Fred D. Finkelman Gill H. Strejan 《Journal of neuroimmunology》1992,36(2-3)
SJL/J mice challenged with myelin basic protein (MBP) in complete Freund's adjuvant (CFA) developed only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence. However, treatment of challenged mice with anti-infeferonγ (IFN-γ) monoclonal antibody (mAb) determined severe disease in all cases. Similarly, in passive EAE, the addition of anti-IFN-γ to the in vitro MBP-activated cells at the time of transfer led to significant disease exacerbation in all recipients. The disease enhancing effect was observed only when the mAb was given at the time of active challenge or of passive transfer, but not at later times. Anti-interleukin-2 (IL-2) antibody had only a marginal effect in the active induction, but drastically reduced the manifestations of passive EAE, even when mixed with a disease-enhancing dose of anti-IFN-γ. These findings support the notion that IL-2 is required for disease induction whereas IFN-γ plays a disease-limiting role early in the development of EAE. 相似文献