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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla. 总被引:2,自引:0,他引:2
Dirk Mayer Dong-Hyun Kim Elfar Adalsteinsson Daniel M Spielman 《Magnetic resonance in medicine》2006,55(5):974-978
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner. 相似文献
2.
3.
CT evaluation of Crohn's disease: effect on patient management 总被引:8,自引:0,他引:8
E K Fishman E J Wolf B Jones T M Bayless S S Siegelman 《AJR. American journal of roentgenology》1987,148(3):537-540
CT scans from 80 consecutive patients with clinically symptomatic Crohn's disease were reviewed retrospectively to determine the effect of CT diagnosis on patient management. The initial clinical impression and any subsequent change in patient management because of the CT findings were noted. In 22 (28%) of the 80 patients, significant previously unsuspected findings led to a change in medical or surgical management. These included 12 patients with fistulae, four with abscess, two with avascular necrosis of the femoral head, two with sacral osteomyelitis, and single cases of pelvic inflammatory disease and femoral vein thrombosis. 相似文献
4.
R J Gatchel T G Mayer P Capra J Barnett P Diamond 《Archives of physical medicine and rehabilitation》1986,67(12):878-882
The present study evaluated the use of psychologic measures, in particular, the relatively new Million Behavioral Health Inventory (MBHI), in predicting change in physical function of chronic low back pain patients undergoing a functional restoration program. The first 134 consecutive patients completing this program were assessed. Results demonstrated that various clinical scales of the MBHI were predictive of improvement in physical function. In addition, various scales enabled discrimination between patients who completed the program and those who prematurely dropped out. Although this inventory shows promise in helping to predict response to treatment, no single psychologic test can reliably be used as the sole predictor in clinical cases. 相似文献
5.
F Reichenberger R Voswinckel B Enke M Rutsch E El Fechtali T Schmehl H Olschewski R Schermuly N Weissmann H A Ghofrani F Grimminger E Mayer W Seeger 《The European respiratory journal》2007,30(5):922-927
For chronic thromboembolic pulmonary hypertension not amenable to pulmonary endarterectomy, effective medical therapy is desired. In an open-label uncontrolled clinical trial, 104 patients (mean +/- sem age 62 +/- 11 yrs) with inoperable chronic thromboembolic pulmonary hypertension were treated with 50 mg sildenafil t.i.d. At baseline, patients had severe pulmonary hypertension (pulmonary vascular resistance 863 +/- 38 dyn.s.cm(-5)) and a 6-min walking distance of 310 +/- 11 m. Eight patients were in World Health Organization functional class II, 76 in class III and 20 in class IV. After 3 months' treatment, there was significant haemodynamic improvement, with reduction of pulmonary vascular resistance to 759 +/- 62 dyn.s.cm(-5). The 6-min walking distance increased significantly to 361 +/- 15 m after 3 months' treatment, and to 366 +/- 18 m after 12 months' treatment. A subset of 67 patients received a single dose of 50 mg sildenafil during initial right heart catheterisation. The acute haemodynamic effect of this was not predictive of long-term outcome. In this large series of patients with inoperable chronic thromboembolic pulmonary hypertension, open-label treatment with sildenafil led to significant long-term functional improvement. The acute effect of sildenafil may not predict the long-term outcome of therapy. 相似文献
6.
E J Mayer B W Alderman J G Regensteiner J A Marshall W L Haskell J Baxter R F Hamman 《The American journal of clinical nutrition》1991,53(4):812-820
We evaluated the consistency of three questionnaire methods of assessing work and leisure activity in the rural biethnic population of the San Luis Valley Diabetes Study. A 7-d physical activity recall (PAR), a ranking of usual activity, and a history of usual participation in vigorous activity were used. Energy expenditure (kJ.kg-1.wk-1) (EE) was estimated from PAR. Subjects were 503 adults [49% non-Hispanic white (NHW), 51% Hispanic]. Physical activity at work rather than leisure-time activity largely determined total energy expenditure. Average EE at work increased with work rank for all subjects combined [mean EE (SEE) for rank 1 (low) = 324.2 (24.4), rank 4 (high) = 874.0 (102.1)] and within sex, ethnic, and occupational subgroups. Leisure EE increased with leisure rank only for NHW men and employed women. Similar patterns were observed in comparisons of PAR data with history of vigorous activity. Further development and validation of instruments appropriate for use across population subgroups are needed. 相似文献
7.
Jutta Liebau Stephanie Heidrich Alfred Berger Mayer Tenenhaus Hans-Oliver Rennekampff 《European journal of plastic surgery》2007,29(5):235-242
Re-epithelialization of cutaneous wounds is a coordinated process of proliferation and migration of keratinocytes at the wound
edge. The study objective was to identify the differences in epidermal morphology, keratinocyte proliferation and matrix molecules
(laminin 1, laminin 5, type IV collagen) and their specific integrin (α3, α6) expression in biopsies of meshed split thickness
grafted and chronic wounds. The mean mitotic index of keratinocytes (ratio of cell cycle associated antigen Ki-67 expressing
keratinocytes to basal keratinocytes) was highest in chronic wounds (38.7%) compared to acute wounds (22.25%, range 5.7% to
54%). The mean thickness of the hyper-proliferative epithelium at the wound edge of chronic wounds was 0.69 mm compared to
0.15 mm at the wound margin of split thickness grafted wounds. Both chronic wounds and skin grafted wounds exhibited strong
laminin 5 immunoreactivity at the basal side of the epithelium, which extended under the most forward keratinocytes. Laminin
1 and type IV collagen immunoreactivity did not extend to the wound margin in either skin grafted or chronic wounds. In both
transplanted skin and chronic wounds, the integrin sub-units α3 and α6 exhibited a strong pericellular immunoreactivity on
the leading keratinocytes of the wound margin. Our data demonstrates that the proliferation of keratinocytes and the expression
of associated integrins are not impaired in chronic wounds.
Presented at the 33rd Congress of the Association of German Plastic Surgeons, Germany, 18–21 September, 2002. 相似文献
8.
Cultured brain cells from rat fetuses of ethanol-treated mothers demonstrated more than 2-fold elevations in choline acetyltransferase (ChAT) activity relative to those of control (saline-exposed) fetal brain cells. When cells from control animals were incubated in vitro for 5 days with 0.1% ethanol, ChAT activity was found to increase more than 4-fold. Brain cells from in utero ethanol-treated animals further exposed to ethanol in vitro for 5 days demonstrated significantly higher ChAT activity compared to cells exposed to ethanol only in vivo. These levels were more than 6 times greater than those of central nervous system cells never exposed to ethanol. Acetylcholinesterase (AChE) activity was significantly elevated (greater than 4-fold) in fetal brain cells when ethanol was present both in vivo and in vitro, but neither treatment alone resulted in any significant changes in AChE. These effects of ethanol on enzymes involved in acetylcholine metabolism may contribute to the different developmental neurologic abnormalities associated with fetal alcohol exposure. 相似文献
9.
The ability of human bladder tissue extracts to cleave 14C-labelled globin in the absence and in the presence of plasminogen was assayed to quantify non-specific protease and plasminogen activator (PA) activity, respectively. In normal human bladder tissue the non-specific protease activity was approximately 2-fold higher than in tissue samples obtained from transitional cell carcinoma of the bladder (TCC). In contrast, PA activity was almost 4-fold higher in TCC than in normal transition cell epithelium. Acid-treated urine from 19 patients with TCC of the bladder exhibited significantly higher levels of plasminogen activator activity than similarly treated urine from controls. These results indicate that malignant transformation of the bladder epithelial tissue results in elevated levels of PA in the tissue and in urine. Further studies are needed to assess the potential of PA determination in the management of bladder cancer patients. 相似文献
10.
Intestinal intraepithelial lymphocytes (iIEL) are primarily CD8 cells and most of them have a CD28? phenotype, the phenotype of effector cytotoxic T cells. We asked whether the predominance of CD8+ CD28? T cells in the gut may result from peripheral blood T cells preferentially migrating to the iIEL compartment and adhering to iEC. Compared with CD4 cells, adhesion of resting CD8+ T cells to iEC cell lines was significantly higher. Adhesion could be blocked with a MoAb to gp180, a molecule expressed on iEC which is known to interact with CD8/lck. No significant difference in the level of adhesion was observed between CD8+ CD28+ and CD8+ CD28? T cells. Thus CD8 cells may preferentially migrate to the iIEL compartment, but loss of CD28 expression could occur in situ after migration. Consistent with this hypothesis, the CD8+ CD28? cells became enriched after co-culturing T cells with iEC cell lines and primary iEC. Induction of the CD8+ CD28? phenotype in cord blood and adult T cells was observed in co-cultures with iEC and also with mitogens and superantigens. In the latter case, CD28 down-modulation was seen specifically in the Vβ subset targeted by the superantigen, indicating that loss of CD28 expression is a direct result of T cell receptor (TCR)-mediated stimulation. The combined results suggest that CD8+ CD28? T cells are antigen experienced T cells, and that they may have a survival advantage in the presence of gut epithelial cells in vitro. This may contribute to the predominance of CD8+ CD28? T cells in the iIEL compartment. 相似文献