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101.
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
102.
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
103.
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
104.
105.
106.
Wierzbicki AS; Lumb PJ; Semra YK; Crook MA 《QJM : monthly journal of the Association of Physicians》1998,91(4):291-294
Lipid targets can be difficult to attain in familial hypercholesterolaemia.
To compare atorvastatin with simvastatin- fenofibrate and
simvastatin-cholestyramine therapy, we studied 54 patients with familial
hypercholesterolaemia over periods of 2-6 months on each therapeutic
regimen. The atorvastatin regimen reduced total cholesterol by 41.2 +/-
11.2%, LDL by 45.6 +/- 15.5%, triglycerides by 33.8 +/- 24.8%, and
increased HDL by 2.3 +/- 37.0%. Simvastatin- fenofibrate therapy achieved
reductions of 33.9 +/- 8.5% in cholesterol, 42.0 +/- 12.2% in LDL, 34.7 +/-
38.3% for triglycerides, and a 25.4 +/- 55.1% increase in HDL.
Simvastatin-cholestyramine gave a reduction of 31.3 +/- 11.8% in
cholesterol, 36.0 +/- 14.4% in LDL, 13.7 +/- 36.3% in triglycerides, and a
1.1 +/- 30.3% rise in HDL. The atorvastatin regimen was marginally but not
significantly better than simvastatin-fenofibrate in improving the LDL:HDL
ratio, LDL:apoB and and apolipoprotein B:A1 ratios. Eleven patients (20.4%)
had side- effects: two discontinued atorvastatin due to side-effects; two
patients had rashes; six had myalgia and two had diarrhoea.
Gastrointestinal side-effects were described in 16 (30.1%) patients on
simvastatin-cholestyramine therapy and four cases of myalgia (11.2%) were
seen with simvastatin-fenofibrate. In nine patients on atorvastatin (20.4%)
a 30% or greater fall in HDL was observed, compared to five patients with
resin therapy (9.2%) and two with fibrate therapy (5.5%). There were no
significant differences in liver or muscle biochemistry between the
regimens, but atorvastatin did raise transaminase and creatine kinase
concentrations significantly compared to pre-treatment values (p = 0.001).
Atorvastatin significantly improves the lipid profile in most patients
compared with other regimens. It has a comparable incidence of side-effects
to combination therapy regimens.
相似文献
107.
The mouse monoclonal antibody M2A1 of IgG1 class, which is highly specific for blood group M antigen, was obtained and characterized by means of hemagglutination, enzyme-linked immunosorbent assay, immunoblotting, and inhibition assays. The use of modified M glycoprotein preparations for inhibition tests and of variant McN and Henshaw red cell membranes for immunoblotting showed that M2A1 recognized an epitope including the NH2-terminal serine and sialic acid residues of glycophorin A, whereas the fifth glycine residue was not involved. The reactivity of the antibody with M antigen was distinctly dependent on ionic strength and pH; the optimum was at pH 8 to 9. The alpha-amino group of terminal serine residue was not necessary for the reaction with M2A1 antibody, and the results obtained suggested that the positive charge of this group contributed to decreasing antigen-antibody reactions at pH below 8. The reaction of the antibody with blood group N antigen was not detectable in any of the assays used. 相似文献
108.
MATÍAS PÉREZ-PAREDES FRANCISCO PICÓ-ARACIL RAFAEL FLORENCIANO JOSÉ G. SÁNCHEZ-VILLANUEVA JOSÉ ANTONIO RUIZ ROS JUAN A. RUIPÉREZ 《Pacing and clinical electrophysiology : PACE》1999,22(8):1173-1178
This study was designed to examine the "true sensitivity" of a specific head-up tilt (HUT) testing protocol using clinical findings. The HUT protocol used 45 minutes at 60 degrees for the baseline portion and intermittent boluses of 2, 4, and 6 micrograms of isoproterenol in the second phase. Eighty-eight patients (40 men and 48 women; mean age of 33.8 +/- 16 years) with recurrent syncope and high pretest likelihood of neurally mediated syncope were included. The following were considerated as high pretest likelihood criteria: (1) at least two syncopal episodes; (2) no structural heart disease and normal baseline ECG; (3) age < 65 years; (4) a typical history of neurally mediated syncope, triggering factors plus premonitory signs; and (5) short duration of symptoms and fast recovery without neurological sequelae. Fifty-four patients (61%) had a positive tilt test (34/88 baseline [39%] and 20/50 with isoproterenol [40%]). The shorter time interval between the last syncopal episode and baseline HUT test was the only predictor for a positive response (P < 0.003). Conversely, this time interval was not predictor of positive responses during isoproterenol-tilt testing. In conclusion: (1) we claim a "sensitivity" for this combined protocol of 61%; and (2) our results indicate that patients with syncope of unknown origin must be tilted nearest as possible to the last syncope to increase the positive responses of HUT test. 相似文献
109.
Laparoscopic cholecystectomy is the standard procedure for symptomatic gall stone disease. Situs inversus is a condition where the visceral anatomy is reversed. Laparoscopic cholecystectomy in a patient of situs inversus is a technically difficult procedure. Six patients of situs inversus underwent laparoscopic cholecystectomy from January 2003 to December 2009. In the first patient of situs inversus, we operated by placing the ports in mirror image fashion as that of standard laparoscopic cholecystectomy. However in next five patients we modified the technique by interchanging the epigastric and left mid clavicular line ports to overcome the problem of handedness. The procedure was successfully completed in all six patients. No intraoperative or postoperative complications occurred. The mean operating time was 65 mins (45–85 mins). Laparoscopic cholecystectomy is safe in patients of situs inversus. However, extreme care and skill is required to identify the reversed anatomy and to overcome the problem of handedness. Interchanging the epigastric and left mid clavicular line ports makes the procedure easier. 相似文献
110.
Om Parkash Aysha Almas SM Wasim Jafri Saeed Hamid Jaweed Akhtar Hasnain Alishah 《BMC gastroenterology》2010,10(1):43