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排序方式: 共有458条查询结果,搜索用时 15 毫秒
71.
72.
Color-Doppler sonography in chronic venous insufficiency: what the radiologist should know 总被引:1,自引:0,他引:1
Cina A Pedicelli A Di Stasi C Porcelli A Fiorentino A Cina G Rulli F Bonomo L 《Current problems in diagnostic radiology》2005,34(2):151-62
Chronic venous insufficiency (CVI) is a pathologic condition caused by valvular incompetence, with or without associated venous outflow obstruction, which may affect both the superficial and the deep venous system, causing venous hypertension and stasis. The most common form of CVI is primary varicose veins due to the insufficiency of the saphenous system. Color-Doppler sonography (CDS) is actually the main diagnostic technique of imaging for CVI. In this article, we describe the anatomy, the technique, and the information necessary to the radiologist to perform CDS in chronic venous insufficiency. The knowledge of the venous anatomy is the cornerstone for an adequate sonographic examination. The venous network in the lower extremities is divided into three systems: superficial, deep, and perforating veins. Deep veins are "comitantes" to the corresponding arteries and run under the muscular fascia. Superficial veins course into the subcutaneous fat, superficially to the deep muscular fascia; the main superficial veins are the greater and lesser saphenous and their tributaries. Connection between the saphenous veins are defined as communicating veins. Superficial and deep veins are connected by perforating veins, with flow directed, under normal circumstances, from the superficial to the deep system. The main perforating are the Hunter in the mid thigh, the Dodd in the lower thigh, the Boyd in the upper calf, and the Cockett's in the middle and lower calf. Sonographic examination must be performed in the upright and supine position. Compression sonography and color and PW Doppler are systematically employed to assess the absence of deep venous thrombosis. Femoro-popliteal veins are evaluated with color and PW Doppler for valvular insufficiency with reflux by performing Valsalva maneuver and calf compression. The sapheno-femoral and sapheno-popliteal junctions are examined to identify type of junction, continence, accessory saphenous, and incompetent collaterals. Perforating veins are usually identified at the medial aspect of the thigh and at the medial, lateral, and posterior aspects of the leg. Outward flow (lasting more than 500 ms) in the perforating veins should be considered a sign of their incompetence. Several surgical and interventional procedures are now available for the treatment of the CVI, as follows: vein ligation and stripping, stab avulsion, endoluminal occlusion of the saphenous trunks, subfascial endoscopic perforator surgery, and valvuloplasty. 相似文献
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Owczarczyk K Lal P Abbas AR Wolslegel K Holweg CT Dummer W Kelman A Brunetta P Lewin-Koh N Sorani M Leong D Fielder P Yocum D Ho C Ortmann W Townsend MJ Behrens TW 《Science translational medicine》2011,3(101):101ra92
An important goal for personalized health care is the identification of biomarkers that predict the likelihood of treatment responses. Here, we tested the hypothesis that quantitative mRNA assays for B lineage cells in blood could serve as baseline predictors of therapeutic response to B cell depletion therapy in subjects with rheumatoid arthritis (RA). In samples from the REFLEX trial of rituximab in inadequate responders to antibodies to tumor necrosis factor-α, a 25% subgroup of treated subjects with elevated baseline mRNA levels of IgJ, a marker for antibody-secreting plasmablasts, showed reduced clinical response rates. There were no significant efficacy differences in the placebo arm subjects stratified by this marker. Prospective testing of the IgJ biomarker in the DANCER and SERENE rituximab clinical trial cohorts and the SCRIPT ocrelizumab cohort confirmed the utility of this marker to predict nonresponse to anti-CD20 therapy. A combination mRNA biomarker, IgJhiFCRL5lo, showed improved test performance over IgJhi alone. This study demonstrates that baseline blood levels of molecular markers for late-stage B lineage plasmablasts identify a ~20% subgroup of active RA subjects who are unlikely to gain substantial clinical benefit from anti-CD20 B cell depletion therapy. 相似文献
75.
Gastroenterologists are often faced with the diagnostic problem of differentiating acute symptoms of ulcerative colitis from functional intestinal disorders. Bowel obsession syndrome (BOS) is an OCD-like, functional syndrome characterized by fear of fecal incontinence and compulsive behaviors of evacuation-checking. Only sparse case studies on treatment of BOS with antidepressants have been published. This is the first study on successful psychotherapy of a male patient with ulcerative colitis overlapping functional bowel symptoms and marked symptoms of BOS. Clinical recognition of BOS may help clinicians in differential diagnosis, prevent unnecessary investigations, and give patients the most appropriate treatment. 相似文献
76.
Lanfranconi F Borrelli E Ferri A Porcelli S Maccherini M Chiavarelli M Grassi B 《Medicine and science in sports and exercise》2006,38(8):1374-1383
PURPOSE: The main aim of the present study was to investigate skeletal muscle oxidative metabolism in heart transplant recipients (HTR) by noninvasive tools. METHODS: Twenty male HTR (age 50.4 +/- 2.6 yr; mean +/- SE) and 17 healthy untrained age-matched controls (CTRL) performed an incremental exercise (IE) and a series of constant-load (CLE) moderate-intensity exercise tests on a cycloergometer. The following variables were determined: heart rate (HR); breath-by-breath pulmonary O2 uptake (VO2); and skeletal muscle (vastus lateralis) oxygenation indices by continuous-wave near-infrared spectroscopy. Changes in concentration of deoxygenated hemoglobin (Hb) and myoglobin (Mb) (Delta[deoxy(Hb + Mb)]), expressed as a fraction of values obtained during a transient limb ischemia, were taken as an index of skeletal muscle O2 extraction. "Peak" values were determined at exhaustion during IE. Kinetics of adjustment of variables were determined during CLE. RESULTS: VO2peak, HRpeak, and Delta[deoxy(Hb + Mb)] peak were significantly lower in HTR than in CTRL (17.1 +/- 0.7 vs 34.0 +/- 1.9 mL.kg(-1).min(-1), 133.8 +/- 3.8 vs 173.0 +/- 4.8 bpm, and 0.42 +/- 0.03 vs 0.58 +/- 0.04, respectively). In HTR, Delta[deoxy(Hb + Mb)] increase at submaximal workloads was steeper than in CTRL, suggesting an impaired O2 delivery to skeletal muscles, whereas the lower Delta[deoxy(Hb + Mb)] peak values suggest an impaired capacity of O2 extraction at peak exercise. VO2 and HR kinetics during CLE were significantly slower in HTR than in CTRL, whereas, unexpectedly, no significant differences were found for Delta[deoxy(Hb+Mb)] kinetics (mean response time: 21.3 +/- 1.1 vs 20.2 +/- 1.2 s). CONCLUSION: The findings confirm the presence of both "central" (cardiovascular) and "peripheral" (at the skeletal muscle level) impairments to oxidative metabolism in HTR. The noninvasiveness of the measurements will allow for serial evaluation of the patients, in the presence and/or absence of rehabilitation programs. 相似文献
77.
Combined natural killer T-cell based immunotherapy eradicates established tumors in mice 总被引:3,自引:0,他引:3
Teng MW Westwood JA Darcy PK Sharkey J Tsuji M Franck RW Porcelli SA Besra GS Takeda K Yagita H Kershaw MH Smyth MJ 《Cancer research》2007,67(15):7495-7504
A rational monoclonal antibody (mAb)-based antitumor therapy approach has previously been shown to eradicate various established experimental and carcinogen-induced tumors in a majority of mice. This therapy comprised an agonistic mAb reactive with tumor necrosis factor-related apoptosis-inducing ligand receptor (DR5), expressed by tumor cells, an agonistic anti-CD40 mAb to mature dendritic cells, and an agonistic anti-4-1BB mAb to costimulate CD8(+) T cells. Because agonists of CD40 have been toxic in patients, we were interested in substituting anti-CD40 mAb with other dendritic cell-maturing agents, such as glycolipid ligands recognized by invariant natural killer T (iNKT) cells. Here, we show that CD1d-restricted glycolipid ligands for iNKT cells effectively substitute for anti-CD40 mAb and reject established experimental mouse breast and renal tumors when used in combination with anti-DR5 and anti-4-1BB mAbs (termed "NKTMab" therapy). NKTMab therapy-induced tumor rejection was dependent on CD4(+) and CD8(+) T cells, NKT cells, and the cytokine IFN-gamma. NKTMab therapy containing either alpha-galactosylceramide (alpha-GC) or alpha-C-galactosylceramide (alpha-c-GC) at high concentrations induced similar rates of tumor rejection in mice; however, toxicity was observed at the highest doses of alpha-GC (>250 ng/injection), limiting the use of this glycolipid. By contrast, even very low doses of alpha-c-GC (25 ng/injection) retained considerable antitumor activity when used in combination with anti-DR5/anti-4-1BB, and thus, alpha-c-GC showed a considerably greater therapeutic index. In summary, sequential tumor cell apoptosis and amplification of dendritic cell function by NKT cell agonists represents an exciting and novel approach for cancer treatment. 相似文献
78.
Recognition of pollen-derived phosphatidyl-ethanolamine by human CD1d-restricted gamma delta T cells
Russano AM Agea E Corazzi L Postle AD De Libero G Porcelli S de Benedictis FM Spinozzi F 《The Journal of allergy and clinical immunology》2006,117(5):1178-1184
BACKGROUND: Evidences from mice and human beings indicate that gammadelta T cells could be relevant in recognition of stress-induced self and/or yet unidentified inhaled foreign antigens. Their specificity differs from classic MHC-restricted alphabeta T cells and involves the immunoglobulin-like structure of the gammadelta T-cell receptor with the recognition of small organic molecules, alkylamines, and self lipid compounds presented by CD1+ dendritic cells. OBJECTIVE: Because CD1 receptors are mainly devoted to lipid antigen presentation, we sought to determine whether exogenous pollen membrane lipids may act as allergens for CD1-restricted gammadelta T cells. METHODS: Peripheral blood and nasal mucosa-associated gammadelta T cells were cloned from normal controls and cypress-sensitive subjects and tested for their antigen specificity and CD1-restriction with phospholipids extracted from tree pollen grains, as well with other natural or synthetic compounds. Phospholipid reactivity of cloned gammadelta T cells was measured by mean of proliferative response and cytokine release as well as by testing their helper activity on IgE production in vitro and in vivo. RESULTS: Cloned gammadelta T lymphocytes from subjects with allergy, but not normal controls, were found to recognize pollen-derived phosphatidyl-ethanolamine (PE) in a CD1d-restricted fashion. Only 16:0/18:2 and 18:2/18:2 PE were stimulatory, whereas no response was recorded for disaturated PE, phosphatidylcholine, neutral lipids, or protein extract. Proliferating clones secreted both T(H)1-type and T(H)2-type cytokines and drove IgE production in vitro and in vivo. CONCLUSION: CD1d-restricted gammadelta T cells specific for phospholipids can represent a key mucosal regulatory subset for the control of early host reactivity against tree pollens. CLINICAL IMPLICATIONS: By knowing how lipid allergen constituents interact with mucosal immune system, we can expand our possibilities in diagnostic and therapeutic interventions. 相似文献
79.
Sambandamurthy VK Derrick SC Hsu T Chen B Larsen MH Jalapathy KV Chen M Kim J Porcelli SA Chan J Morris SL Jacobs WR 《Vaccine》2006,24(37-39):6309-6320
The global epidemic of tuberculosis (TB), fueled by the growing HIV pandemic, warrants the development of a safe and effective vaccine against TB. We report the construction and characterization of an unlinked double deletion mutant of Mycobacterium tuberculosis H37Rv that deletes both the primary attenuating mutation of BCG (DeltaRD1) and two genes required for the synthesis of pantothenate (DeltapanCD). The M. tuberculosis DeltaRD1 DeltapanCD (mc(2)6030) mutant undergoes limited replication in mice, and yet is both significantly safer than BCG in immunocompromised mice and also safe in guinea pigs. Additionally, the mc(2)6030 strain does not reactivate in a mouse chemo-immunosuppression model. Importantly, long-lived protective immune responses following immunization with the mc(2)6030 strain prolong the survival of wild type mice, and CD4-deficient mice against an aerosol challenge with virulent M. tuberculosis. Given its overall safety and effectiveness, the mc(2)6030 live attenuated strain should be considered as a human vaccine candidate for protecting both healthy and HIV-infected individuals against TB. 相似文献
80.