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排序方式: 共有1023条查询结果,搜索用时 31 毫秒
81.
Congenital abnormalities of the aortic arch: MR imaging 总被引:1,自引:0,他引:1
Thirty-four patients, 1 month to 63 years old, with known or suspected congenital abnormalities of the aortic arch underwent magnetic resonance (MR) imaging. Sixteen patients were studied retrospectively, 18 prospectively. In all retrospective studies, the aortic arch abnormality was seen with MR imaging. In the prospective studies, MR imaging enabled diagnosis in 15 of 18 (83%) patients. Twenty-nine of 34 patients underwent two-dimensional echocardiography; nine were studied retrospectively, 20 prospectively. In the prospective studies, echocardiography enabled diagnosis in 13 of 20 (65%) patients. Although two-dimensional echocardiography has a high sensitivity in the detection of aortic arch abnormalities in the neonate, arch abnormalities in the neonate, its sensitivity is lower in older children, adults, and postoperative patients. The authors' experience shows that MR imaging is an important, noninvasive modality in the evaluation of older children, adults, and postoperative patients with congenital aortic arch abnormalities. 相似文献
82.
R. LA TOUCHE C. FERNÁNDEZ-DE-LAS-PEÑAS J. FERNÁNDEZ-CARNERO K. ESCALANTE S. ANGULO-DÍAZ-PARREÑO A. PARIS-ALEMANY & J. A. CLELAND 《Journal of oral rehabilitation》2009,36(9):644-652
Summary No studies have investigated the effects of the treatments directed at the cervical spine in patients with temporomandibular disorders (TMD). Our aim was to investigate the effects of joint mobilization and exercise directed at the cervical spine on pain intensity and pressure pain sensitivity in the muscles of mastication in patients with TMD. Nineteen patients (14 females), aged 19–57 years, with myofascial TMD were included. All patients received a total of 10 treatment session over a 5‐week period (twice per week). Treatment included manual therapy techniques and exercise directed at the cervical spine. Outcome measures included bilateral pressure pain threshold (PPT) levels over the masseter and temporalis muscles, active pain‐free mouth opening (mm) and pain (Visual Analogue Scale) and were all assessed pre‐intervention, 48 h after the last treatment (post‐intervention) and at 12‐week follow‐up period. Mixed‐model anovas were used to examine the effects of the intervention on each outcome measure. Within‐group effect sizes were calculated in order to assess clinical effect. The 2 × 3 mixed model anova revealed significant effect for time (F = 77·8; P < 0·001) but not for side (F = 0·2; P = 0·7) for changes in PPT over the masseter muscle and over the temporalis muscle (time: F = 66·8; P < 0·001; side: F = 0·07; P = 0·8). Post hoc revealed significant differences between pre‐intervention and both post‐intervention and follow‐up periods (P < 0·001) but not between post‐intervention and follow‐up period (P = 0·9) for both muscles. Within‐group effect sizes were large (d > 1·0) for both follow‐up periods in both muscles. The anova found a significant effect for time (F = 78·6; P < 0·001) for changes in pain intensity and active pain‐free mouth opening (F = 17·1; P < 0·001). Significant differences were found between pre‐intervention and both post‐intervention and follow‐up periods (P < 0·001) but not between the post‐intervention and follow‐up period (P > 0·7). Within‐group effect sizes were large (d > 0·8) for both post‐intervention and follow‐up periods. The application of treatment directed at the cervical spine may be beneficial in decreasing pain intensity, increasing PPTs over the masticatory muscles and an increasing pain‐free mouth opening in patients with myofascial TMD. 相似文献
83.
To assess the safety of magnetic resonance (MR) imaging in women who have an intrauterine contraceptive device (IUD) in place, in vitro and in vivo studies were performed at both 0.35 and 1.5 T. Two commonly used IUDs were tested, one all of plastic, the other with a coil of copper wire on it. Specifically, the study assessed possible motion of the IUD in the magnetic field, potential of the IUD to heat up during two spin-echo imaging sequences commonly used in MR imaging of the pelvis (2,000/30 and 60 [repetition time, msec/echo time, msec], and 500/30), and the appearance on MR images of the IUD devices. A retrospective review of MR images of the pelvis in six women who had an IUD in place was also performed. Results show that an IUD does not move under the influence of the magnetic field, does not heat during spin-echo sequences commonly used for pelvic imaging, and does not produce artifacts in vitro or in vivo. Patients with either type of IUD can be safely imaged with MR, and MR images of the pelvis are not degraded by the presence of an IUD. 相似文献
84.
Girija B. Bhavar V. A. Chatpalliwar D. D. Patil S. J. Surana 《Indian journal of pharmaceutical sciences》2008,70(4):529-531
Quinapril hydrochloride and hydrochlorothiazide were simultaneously determined by HPTLC in pharmaceutical formulations. The drugs were separated on silica gel 60 F254 plates using suitable combination of solvents as mobile phase. The validation parameters, tested in accordance with the requirements of ICH guidelines, prove the suitability of methods. 相似文献
85.
Ammanamanchi S R Anjaneyulu Vadali Lakshmana Rao Vedula Girija Sastry Desaraju Venkata Rao 《Journal of Asian natural products research》2008,10(7):597-601
A novel rearranged sesquiterpenoid, trocheliophorin (1) has been isolated from the soft coral Sarcophyton trocheliophorum besides the known compounds, sarcophytin, methyl arachidonate, and two polyhydroxy steroids (24S)-24-methylcholestane-3beta,5alpha,6beta,25-tetrol-25-monoacetate and (24S)-24-methylcholestane-3beta,5alpha,6beta,25-tetrol. The structure of the new sesquiterpenoid was elucidated by a study of its spectral data. 相似文献
86.
Lymphoceles: imaging characteristics and percutaneous management 总被引:3,自引:0,他引:3
vanSonnenberg E; Wittich GR; Casola G; Wing VW; Halasz NA; Lee AS; Withers C 《Radiology》1986,161(3):593-596
Twenty-five patients who had lymphoceles underwent sectional imaging and interventional radiologic procedures. Viewed using sonography, lymphoceles were hypoechoic to anechoic, occasionally with internal septa and debris. Low numbers (occasionally negative values) were observed using computed tomography (CT); these numbers strongly suggest the diagnosis of lymphocele. Calcification was observed on CT images of one patient. Diagnostic aspiration revealed tan to yellow fluid containing many lymphocytes; pathognomonic fat globules were observed in four cases. Malignant cells were found in two collections, an unusual occurrence. Therapeutic needle aspiration and short-term catheter drainage were usually unsuccessful (only one of five patients [20%] was cured). Long-term (1-5-week) catheter drainage cured 11 of 14 patients (78.6%). Sclerosing agents may have been beneficial for lymphocele obliteration in three of four patients. For most patients, lymphoceles may be diagnosed and treated successfully using radiologic means. 相似文献
87.
Novel nonnucleoside inhibitor of hepatitis C virus RNA-dependent RNA polymerase 总被引:4,自引:0,他引:4
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Howe AY Bloom J Baldick CJ Benetatos CA Cheng H Christensen JS Chunduru SK Coburn GA Feld B Gopalsamy A Gorczyca WP Herrmann S Johann S Jiang X Kimberland ML Krisnamurthy G Olson M Orlowski M Swanberg S Thompson I Thorn M Del Vecchio A Young DC van Zeijl M Ellingboe JW Upeslacis J Collett M Mansour TS O'Connell JF 《Antimicrobial agents and chemotherapy》2004,48(12):4813-4821
A novel nonnucleoside inhibitor of hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp), [(1R)-5-cyano-8-methyl-1-propyl-1,3,4,9-tetrahydropyano[3,4-b]indol-1-yl] acetic acid (HCV-371), was discovered through high-throughput screening followed by chemical optimization. HCV-371 displayed broad inhibitory activities against the NS5B RdRp enzyme, with 50% inhibitory concentrations ranging from 0.3 to 1.8 microM for 90% of the isolates derived from HCV genotypes 1a, 1b, and 3a. HCV-371 showed no inhibitory activity against a panel of human polymerases, including mitochondrial DNA polymerase gamma, and other unrelated viral polymerases, demonstrating its specificity for the HCV polymerase. A single administration of HCV-371 to cells containing the HCV subgenomic replicon for 3 days resulted in a dose-dependent reduction of the steady-state levels of viral RNA and protein. Multiple treatments with HCV-371 for 16 days led to a >3-log10 reduction in the HCV RNA level. In comparison, multiple treatments with a similar inhibitory dose of alpha interferon resulted in a 2-log10 reduction of the viral RNA level. In addition, treatment of cells with a combination of HCV-371 and pegylated alpha interferon resulted in an additive antiviral activity. Within the effective antiviral concentrations of HCV-371, there was no effect on cell viability and metabolism. The intracellular antiviral specificity of HCV-371 was demonstrated by its lack of activity in cells infected with several DNA or RNA viruses. Fluorescence binding studies show that HCV-371 binds the NS5B with an apparent dissociation constant of 150 nM, leading to high selectivity and lack of cytotoxicity in the antiviral assays. 相似文献
88.
Walker AS; Peto TE; Babiker AG; Darbyshire JH 《QJM : monthly journal of the Association of Physicians》1998,91(6):423-438
The Concorde trial compared immediate (Imm) with deferred (Def) AZT
monotherapy in asymptomatic HIV-positive participants. Haematological and
immunological markers and weight were measured throughout, and correlated
with clinical endpoints. Markers associated with disease progression (CD4
lymphocyte count and percentage, platelets, p24 antigen and beta 2
microglobulin favoured Imm: those associated with toxicity (haemoglobin,
neutrophils and white cell count) favoured Def. CD8 and total lymphocyte
count did not differ significantly between groups. In multivariate
analysis, the combination of baseline CD4, p24 antigen and beta 2m was the
best baseline predictor of disease. Including change in CD4 and beta 2m at
12 weeks, or changes over follow- up in these markers significantly
improved the fit. Markers were also incorporated into the definition of
'clinical' endpoints. Hazard ratio estimates from end-points that included
CD4 < 50 and CD4 < 25 were closest to those for AIDS or death alone,
but added very few extra events. Use of other landmark CD4 counts (100 or
greater) or relative decreases in counts (25% or more) increased the number
of events, but overestimated the effect of immediate AZT. Although AZT had
a beneficial effect on the surrogate markers of efficacy evaluated, these
changes did not predict clinical outcome, nor could the markers be usefully
incorporated into an endpoint definition.
相似文献
89.
90.