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排序方式: 共有850条查询结果,搜索用时 15 毫秒
31.
Khan N Murphy TP Soares GM Zahir IS 《Journal of vascular and interventional radiology : JVIR》2005,16(12):1753-1757
To identify trends in Evaluation and Management (E&M) and non-E&M services of interventional radiologists (physician specialty type 94) from 2000 to 2003 for Medicare patients, Medicare Part B physician annual allowed services data from the Centers of Medicare and Medicaid Services (CMS) were analyzed for all interventional radiologists from 2000 to 2003. Because the number of interventional radiologists in the United States according to the Society of Interventional Radiology is, on average, 4.2 times the number of interventional radiologists who use physician specialty type 94, we extrapolated the E&M services for each year. During the period examined, the total number of E&M services by interventional radiologists increased 309%, from 9,698 in 2000 to 29,914 in 2003. The most commonly performed services were Office or Other Outpatient Visit (Current Procedural Terminology [CPT] codes 99211-99215) for established patients, followed by Subsequent Hospital Care (CPT 99231-99233) and Office or Other Outpatient Consultations (CPT 99241-99245). The extrapolated number of E&M services by interventional radiologists for Medicare patients in 2003 is approximately 107,853. The number of Office and Outpatient Visits for New Patients (CPT 99201-99205) increased 142%, whereas the number of Consultations for New Patients (CPT 99241-99245) increased 208%. The total number of codes reimbursed by CMS to interventional radiologists (type 94) increased from 2.8 million in 2000 to 3.8 million in 2003. 相似文献
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33.
Kalayci R Kaya M Elmas I Arican N Ahishali B Uzun H Bilgic B Kucuk M Kudat H 《Brain research》2005,1042(2):184-193
Recent studies suggest that 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, statins, can have direct effects on blood vessels beyond their cholesterol-lowering effects. We investigated the effects of atorvastatin on the functional and structural properties of blood-brain barrier (BBB) and the activity of astrocytes during the N(omega)-nitro-L-arginine methyl ester (L-NAME) hypertension followed by angiotensin (ANG) II. We found that decreases in concentration of serum catalase and plasma nitric oxide (NO) induced by L-NAME were significantly ameliorated by atorvastatin, whereas L-NAME-induced serum malondialdehyde and cholesterol concentration increases were significantly reduced by atorvastatin. The content of Evans blue (EB) dye significantly increased in cerebellum, left cerebral cortex and diencephalon regions but atorvastatin markedly reduced the increased BBB permeability to EB in the brain regions of animals treated with L-NAME and L-NAME plus ANG II. Brain vessels of L-NAME-treated animals showed a considerable loss of immunoreactivity of tight junction proteins, zonula occludens (ZO)-1 and occludin. Immunoreactivity for ZO-1 and occludin increased in animals treated with atorvastatin and L-NAME plus atorvastatin. Glial fibrillary acidic protein (GFAP) immunoreactivity was seen in few astrocytes in the brain sections of L-NAME, but immunoreactivity for GFAP increased in L-NAME plus atorvastatin-treated animals. We suggest that long-term L-NAME treatment may affect BBB permeability through disruption of tight junction proteins, at least partly, via decreased NO concentration and increased oxidant capacity; the improvement of BBB integrity and astrocytic activity would be more closely associated with the action of atorvastatin favoring the increase in anti-oxidant capacity and expression of tight junction proteins and GFAP. 相似文献
34.
Ghanem N Altehoefer C Högerle S Nitzsche E Lohrmann C Schäfer O Kotter E Langer M 《European journal of radiology》2005,54(2):264-270
PURPOSE: We evaluated the diagnostic accuracy of magnetic resonance imaging (MRI) and positron emission tomography (PET) for detection of liver metastases in malignant melanoma. MATERIAL AND METHODS: Thirty-five patients with 39 combined unenhanced MRI and fluorine-18 deoxyglucose (F-18 FDG) PET scans were prospectively studied. In discordant imaging findings final diagnosis was proven by clinical follow-up >6 months and demonstration of progressive liver metastases by at least one imaging method. Sensitivities and specificities were compared and the influence of lesion size and melanin content on diagnostic accuracy was determined. RESULTS: MRI and PET were concordantly negative for presence and number of liver metastases in 28 patients and positive in four patients. PET and MRI were false positive in one patient each. In one patient MRI showed a single metastases not seen by PET and in one patient MRI demonstrated more metastases at the first examination. In follow-up investigations MRI revealed more metastases than PET in both patients. The sensitivities for lesion detection were 47% (16/34) for PET and 100% for MRI. Lesion detectability by PET was related to lesion size (P < 0.0001) but not to melanin content. CONCLUSION: MRI is more sensitive in the detection of liver metastases in patients with malignant melanoma. Small lesions are easily missed by PET, while melanin content does not influence detectability by PET. 相似文献
35.
Serum thyroglobulin (Tg) measurement has a pivotal role in the management of differentiated thyroid carcinoma (DTC). Serum Tg increment after thyroid hormone discontinuation seems to be a better predictor of tumor recurrence, however, minimal Tg increment may not be a specific marker. This study tries to evaluate the importance of different levels of Tg increment after thyroid hormone discontinuation. Fifty-five patients (46 females and 9 males with mean age of 41.40 yrs) with DTC, treated with total or subtotal thyroidectomy and radioiodine-131 ((131)I) were studied. Ninety-one per cent of the patients had papillary carcinoma. Serum Tg and thyroid stimulating hormone (TSH) were measured using high sensitive IRMA assays during thyroxine (T4) suppression and after discontinuation of T4 treatment. The mean time interval between Tg on T4 and off T4 was 110.29+/-53.43 days and less than 180 days in all patients. Serum Tg level was increased >or= 1 ng/ml in 25 patients after discontinuation of T4. Of these patients, 17 had metastatic disease or a detectable thyroid remnant. Of 16 patients with unchanged Tg (-1or= 7 ng/ml had residual disease or metastases. If DeltaTg was unchanged or decreased, the negative predictive value was 83.3%. The sensitivity of WB(131)IS was 63.6% for the detection of thyroid remnant or metastases. Our study indicates that DeltaTg is a more reliable indicator of remnant disease than on T4-Tg or off T4-Tg levels. 相似文献
36.
Lohrmann C Uhl M Warnatz K Ghanem N Kotter E Schaefer O Langer M 《European journal of radiology》2004,52(2):137-143
PURPOSE: To assess pulmonary abnormalities in patients with primary Sjogren's syndrome (PSS) using high-resolution computed tomography (HRCT). MATERIAL AND METHODS: The HRCT scans of 24 patients with the diagnosis PSS were retrospectively reviewed regarding the presence, extension and distribution of 16 pathological findings. RESULTS: Nineteen patients (79.2%) showed pathological findings and in five patients (21.8%) the HRCT scan was judged to be normal. A predominance of abnormalities in the lower lobes and subpleural areas was detected. The following pathologies were found: bronchiectasis, thin-walled cysts and small pulmonary nodules (46.2%), ground-glass attenuation and emphysema (37.8%), interlobular-septal thickening (29.4%), honeycombing (25.2%), bronchial wall thickening, tree-in-bud pattern (21.0%), mosaic perfusion (16.8%), architectural distortion (12.6%). Airspace consolidation, air trapping, large nodules (10-30mm) and masses (>30mm), mediastinal lymph node enlargement (>15mm) and free pleural fluid were seen each in 4.2%. In 7 of the 11 patients with thin-walled cysts areas of ground-glass attenuation were detected. CONCLUSION: HRCT seems is contributive to the characterization of the wide variety of lung abnormalities in PSS. Airway disease alone or in association with the presence of varying degrees of interstitial disease represents the main findings in accordance with earlier reports. Unexpectedly, almost half of the patients had thin-walled cysts on the HRCT scans, which etiology is unclear but could be associated with areas of ground-glass attenuation indicating LIP. 相似文献
37.
38.
The ESO Advanced Course on Cancer in the Elderly took place in Liverpool-UK, 29-30 April 2004 under the chair of Riccardo A. Audisio and Matti A. Aapro. This successful event gathered 82 participants from 17 countries; posters were displayed presenting original research data, and 19 lecturers updated the audience on the latest findings regarding basic science, prevention, early detection, diagnosis, treatment options, as well as the social impact of this frequent malignancy. This Meeting Highlights collects the panelists views; it is intended to update on the cutting edge of the present knowledge, in order to improve our understanding of malignant disease affecting senior patients, and eventually to optimise their management. 相似文献
39.
Sensitization of multidrug resistant human ostesarcoma cells to Apo2 Ligand/TRAIL-induced apoptosis by inhibition of the Akt/PKB kinase 总被引:1,自引:0,他引:1
Cenni V Maraldi NM Ruggeri A Secchiero P Del Coco R De Pol A Cocco L Marmiroli S 《International journal of oncology》2004,25(6):1599-1608
Chemotherapeutic agents have been used for the treatment of patients with osteosarcoma (OS). However, inherent or acquired resistance to these agents is a serious problem in the management of OS patients. The emergence of the multidrug resistance (MDR) phenotype in cancer cells is often associated with the overexpression of P-glycoprotein, encoded by the multidrug resistance gene MDR-1. The administration of some of the most common chemotherapeutic agents to these cells becomes ineffective because of their P-gp-driven efflux from the cell. Apo2L/TRAIL is a member of the tumor necrosis factor (TNF) family of cytokines that is considered to induce death of cancer cells but not normal cells. Its powerful apoptotic activity is mediated through its cell surface death domain-containing receptors, TRAIL-R1/DR4 and TRAIL-R2/DR5, which in turn spread the signal in the cytosol through the activation of the caspase cascade. The Akt/PKB kinase is an important cell survival protein which is regulated by D3-phosphoinositides. High Akt expression and activity levels are well documented in many types of tumors, which very often show an altered PI3-K/Akt/PTEN pathway. In this study the U2OS human osteosarcoma cell line and its multidrug resistant (MDR) subline that overexpresses MDR-1 gene, MDR-U2OS, have been analyzed for their responsiveness to TRAIL. In conflict with the presence of active DR4 and DR5 receptors in both clones, U2OS cells exhibited only a low responsiveness to TRAIL, while the MDR-U2OS subline did exhibit a marked TRAIL sensitivity. An analysis of the post-receptor events showed that TRAIL responsiveness correlates with a reduced expression of endogenous Akt. In fact, expression in MDR-U2OS cells of a constitutively active Akt strongly decreased their sensitivity to TRAIL. The identification of Akt as a key modulator of TRAIL responsiveness could help to design TRAIL-based combinations for treatment of osteosarcoma. Moreover, the discovery that multidrug resistant osteosarcomas are highly sensitive to TRAIL-induced apoptosis indicates TRAIL as a new candidate for the treatment of multidrug resistant bone malignancies. 相似文献
40.
Long-term display of exogenous proteins on the cell surface may have important research and therapeutic implications. We report a novel method for the cell-surface display of proteins that involves generation of a chimeric protein with core streptavidin, biotinylation of cells, and "decoration" with the protein. A chimeric protein with the extracellular portions of FasL (SA-FasL) was efficiently displayed on the cell surface within 2 hr without detectable cellular toxicity. Biotin and SA-FasL persisted on the cell surface for weeks in vitro and in vivo. Immunomodulation with SA-FasL-decorated splenocytes effectively blocked alloreactive responses in naive and presensitized rodents and prevented the rejection of allogeneic pancreatic islets. This approach may serve as an alternative to gene transfer-based expression with broad research and therapeutic applications. 相似文献